Dissertations / Theses: 'Jarrah'

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Bunny, F. "The biology, ecology and taxonomy of Phytophthora citricola in native plant communities in Western Australia /." Access via Murdoch University Digital Theses Project, 1996. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20061122.122739.

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Stoneman, Geoff. "Factors affecting the establishment of jarrah (Eucalyptus marginata) from seed in the northern jarrah forest of Western Australia." Thesis, Stoneman, Geoff (1992) Factors affecting the establishment of jarrah (Eucalyptus marginata) from seed in the northern jarrah forest of Western Australia. PhD thesis, Murdoch University, 1992. https://researchrepository.murdoch.edu.au/id/eprint/51965/.

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Field experiments were established on seven sites in the northern jarrah forest of south-west Western Australia to test the effect of (i) overstorey, site, seedbed, seeding date and seed harvesting by vertebrates and invertebrates on emergence, (ii) overstorey, site. seedbed, application of fertiliser and grazing on mortality, and (iii) overstorey, site and application of fertiliser on growth of Eucalyptus marginata seedlings. Rainfall, soil temperature, soil water deficits. leaf water potential and photosynthetically active radiation (PAR) were monitored over two years. Seed harvesting by small vertebrates substantially reduced emergence, whereas invertebrates only slightly reduced emergence. Ninety per cent of seed was removed within one day where it was on the soil surface and in the open, whereas seed removal was insignificant when the seed was covered by soil. Vertebrates harvested seed more effectively when the understorey and litter were removed and the seed was more visible on the soil surface. Seed harvesting by small vertebrates had less impact on a site where there had been bauxite mining possibly because the surrounding area was being revegetated with large numbers of seed and the area afforded poor cover for vertebrates. Emergence was less where the overstorey was removed compared to where it was retained and on the bauxite pit compared to the forest sites. There was no difference in emergence between the low and high quality forest sites and so the emergence phase could not explain the variation in abundance of E. marginata trees on the different quality sites. Seedlings on sites with the overstorey removed experienced significantly higher soil temperatures for nine months of the year (of up to 6°C)/ smaller soil and leaf water deficits during the dry season (minimum predawn leaf water potentials of -0.5 MPa compared to -1.6 MPa), and higher intensities of PAR (maximum values of 1900 [umol m-2 s- compared to 900 1 /jmol m-2 s-1 compared to seedlings on sites with the overstorey retained. Mortality of E. marglnata seedlings was greater on sites where the overstorey was retained compared to where the overstorey was removed, on low quality sites than high quality sites and on undisturbed and lightly disturbed seedbeds compared to heavily disturbed seedbeds. Neither fertilising nor grazing by vertebrates had a statistically significant effect on mortality. Most of the mortality occurred as water deficits developed in late spring and summer and the major cause of mortality was attributed to water deficits. Some mortality occurred prior to this and was probably caused by pathogenic fungi. Mortality of E. marginata seedlings in the northern jarrah forest of Western Australia can be minimised by reducing the density of the overstorey and by seeding into a seedbed which has had litter and ground cover removed and the soil disturbed. Shoot dry weight was eight times greater, leaf area was more than 20 times and photosynthesis was two to 10 times greater on sites with the overstorey removed. Fertilising increased shoot dry weight by a factor of two. For sites with the overstorey removed, seedlings on the high quality site achieved six times the shoot dry weight of those on the bauxite pit and three times the shoot dry weight of those on the low quality site. Shoot dry weight was strongly related to leaf area index, independent of the effects of overstorey, site quality and fertiliser. Leaf growth commenced in spring when soil temperature at 40 cm reached 17°C, it was then primarily limited by water deficits until late autumn when soil temperature fell below 15°C, at which point leaf growth had nearly stopped. Leaf growth and photosynthesis both decreased as water deficits developed over the dry Seedlings season. on the site with the overstorey removed had higher rates of photosynthesis and greater photosynthetic capacity than those on the site with the overstorey retained. To understand the effects of soil temperature, shade by an overstorey and water deficits on seedling growth, a series of controlled environment studies was undertaken where each factor alone was studied. The effect of soil temperature on the growth of E. marginata seedlings was studied in the first glasshouse experiment. Soil temperature had a significant effect on the growth of all plant parts except the cotyledons. Total plant growth and shoot growth were maximal at a soil temperature of 30°C, but root growth had a slightly lower optimum such that the root:shoot ratio was highest at 20°C. Roots grown at 15°C had about 30% less length per unit of DW than those grown at 20 - 35°C. The effect of shade on plant growth, dry weight partitioning and photosynthetic response to light of E. marginata seedlings was studied in the second glasshouse experiment. Plant dry weight and that of all plant parts declined in response to shade, as did the root:shoot ratio. Plant leaf area was less for plants grown under no shade than for plants grown under shade. Specific leaf area increased with shade. Seedlings grown under no shade had a higher light saturated rate of photosynthesis, a higher light compensation point and a higher light saturation level than seedlings grown under 70% shade. E. marginata seedlings responded to shade in a very similar way to other eucalypts which naturally regenerate below an overstorey. Plant dry weight and leaf dry weight were strongly related, independent of shade, whereas the relationship between plant dry weight and plant leaf area was dependent on the level of shade. Therefore, leaf dry weight may be a better predictor of biomass production in forest stands where shade is likely to be a significant factor affecting growth. Leaf growth, net rate of leaf photosynthesis and tissue water relations of shoots of E. marginata seedlings was studied over the course of a soil drying and rewatering cycle in the third glasshouse experiment to determine the effect of water deficits on these parameters. The relationship between midday photosynthesis and predawn leaf water potential showed that photosynthesis of E. marginata seedlings is very sensitive to water deficits. Midday photosynthesis declined to 40% of that of well hydrated seedlings at a predawn leaf water potential of -1 MPa and reached zero at -2.2 MPa. Photosynthesis recovered rapidly following rewatering and was nearly completely recovered by the second day after rewatering. The rate of leaf growth decreased linearly with predawn leaf water potential to reach zero at -1.5 MPa. Leaf growth did not recover completely within the first three days after rewatering. All tissue water relations parameters, except the bulk modulus of elasticity, changed significantly as the soil dried and recovered completely by 3 days after rewatering. The changes in osmotic pressure at full turgor of 0.4 MPa indicates considerable ability by E. marginata seedlings to adjust osmotically. However, there was little osmotic adjustment until predawn leaf water potential fell below -1.5 MPa so it would not have conferred any advantage to the growth of the seedlings, but may aid in survival. The sensitivity of photosynthesis and relative water content to water deficits shows that E. marginata behaves as a mesophyte despite the fact that it grows in a drought-prone environment. The glasshouse experiments dealing with the effects of soil temperature and shade showed that both the higher soil temperatures and the higher light intensities on sites with the overstorey removed could account for significant increases in growth of E. marginata seedlings, but that these effects were a relatively small component of the growth response due to overstorey removal. The glasshouse experiment on the effects of water deficits showed that rates of leaf growth and photosynthesis are very sensitive to water deficits and therefore the greater water deficits that seedlings experienced on sites with the overstorey retained will cause large reductions in the growth of E. marginata seedlings. In conclusion, secondary effects of overstorey removal are increases in soil temperature and light which promote greater growth of E. marginata seedlings. The major effect of overstorey removal is to reduce some of the limits that water deficits impose on growth of E. marginata seedlings in the northern jarrah forest of south west Western Australia. The major factors affecting establishment of E. marginata seedlings in the forest were seed harvesting by small vertebrates which greatly reduced emergence, and water deficits which increased mortality and reduced growth of E. marginata seedlings.

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Wheeler, Margaret Anne. "Reproductive and molecular biology of Eucalyptus marginata Donn ex Smith /." Access via Murdoch University Digital Theses Project, 2003. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20040723.140250.

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Bleby, Timothy Michael. "Water use, ecophysiology and hydraulic architecture of Eucalyptus marginata (jarrah) growing on mine rehabilitation sites in the jarrah forest of south-western Australia." University of Western Australia. School of Plant Biology, 2003. http://theses.library.uwa.edu.au/adt-WU2004.0004.

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[Truncated abstract. Please see the pdf format for the complete text. Also, formulae and special characters can only be approximated here. Please see the pdf version for an accurate reproduction.] This thesis examines the water use, ecophysiology and hydraulic architecture of Eucalyptus marginata (jarrah) growing on bauxite mine rehabilitation sites in the jarrah forest of south-western Australia. The principal objective was to characterise the key environment and plant-based influences on tree water use, and to better understand the dynamics of water use over a range of spatial and temporal scales in this drought-prone ecosystem. A novel sap flow measurement system (based on the use of the heat pulse method) was developed so that a large number of trees could be monitored concurrently in the field. A validation experiment using potted jarrah saplings showed that rates of sap flow (transpiration) obtained using this system agreed with those obtained gravimetrically. Notably, diurnal patterns of transpiration were measured accurately and with precision using the newly developed heat ratio method. Field studies showed that water stress and water use by jarrah saplings on rehabilitation sites were strongly seasonal: being greatest in summer when it was warm and dry, and least in winter when it was cool and wet. At different times, water use was influenced by soil water availability, vapour pressure deficit (VPD) and plant hydraulic conductance. In some areas, there was evidence of a rapid decline in transpiration in response to dry soil conditions. At the end of summer, most saplings on rehabilitation sites were not water stressed, whereas water status in the forest was poor for small saplings but improved with increasing size. It has been recognised that mature jarrah trees avoid drought by having deep root systems, however, it appears that saplings on rehabilitation sites may have not yet developed functional deep roots, and as such, they may be heavily reliant on moisture stored in surface soil horizons. Simple predictive models of tree water use revealed that stand water use was 74 % of annual rainfall at a high density (leaf area index, LAI = 3.1), high rainfall (1200 mm yr-1) site, and 12 % of rainfall at a low density (LAI = 0.4), low rainfall (600 mm yr-1) site, and that water use increased with stand growth. A controlled field experiment confirmed that: (1) sapling transpiration was restricted as root-zone water availability declined, irrespective of VPD; (2) transpiration was correlated with VPD when water was abundant; and (3) transpiration was limited by soil-to-leaf hydraulic conductance when water was abundant and VPD was high (> 2 kPa). Specifically, transpiration was regulated by stomatal conductance. Large stomatal apertures could sustain high transpiration rates, but stomata were sensitive to hydraulic perturbations caused by soil water deficits and/or high evaporative demand. No other physiological mechanisms conferred immediate resistance to drought. Empirical observations were agreeably linked with a current theory suggesting that stomata regulate transpiration and plant water potential in order to prevent hydraulic dysfunction following a reduction in soil-to-leaf hydraulic conductance. Moreover, it was clear that plant hydraulic capacity determined the pattern and extent of stomatal regulation. Differences in hydraulic capacity across a gradient in water availability were a reflection of differences in root-to-leaf hydraulic conductance, and were possibly related to differences in xylem structure. Saplings on rehabilitation sites had greater hydraulic conductance (by 50 %) and greater leaf-specific rates of transpiration at the high rainfall site (1.5 kg m-2 day1) than at the low rainfall site (0.8 kg m-2 day1) under near optimal conditions. Also, rehabilitation-grown saplings had significantly greater leaf area, leaf area to sapwood area ratios and hydraulic conductance (by 30-50 %) compared to forest-grown saplings, a strong indication that soils in rehabilitation sites contained more water than soils in the forest. Results suggested that: (1) the hydraulic structure and function of saplings growing under the same climatic conditions was determined by soil water availability; (2) drought reduced stomatal conductance and transpiration by reducing whole-tree hydraulic conductance; and (3) saplings growing on open rehabilitation sites utilised more abundant water, light and nutrients than saplings growing in the forest understorey. These findings support a paradigm that trees evolve hydraulic equipment and physiological characteristics suited to the most efficient use of water from a particular spatial and temporal niche in the soil environment.

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Woodman, Gregory. "Damping-off of indigenous jarrah forest plant species by Phytophthora cinnamomi and Phytophthora citricola in bauxite pit rehabilitation in the northern jarrah forest." Thesis, Woodman, Gregory (1993) Damping-off of indigenous jarrah forest plant species by Phytophthora cinnamomi and Phytophthora citricola in bauxite pit rehabilitation in the northern jarrah forest. Honours thesis, Murdoch University, 1993. https://researchrepository.murdoch.edu.au/id/eprint/32820/.

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Alcoa of Australia Limited mines bauxite from the Darling Range in south-west Western Australia. They have a goal to replace >80% of plant species indigenous to the surrounding jarrah (Eucalyptus marginata Donn ex Smith) forest in their 15 month old rehabilitation by 1997. Annual monitoring of the 15 month old rehabilitation has identified some plant species that germinate well in glasshouse and laboratory trials but were not returning to the rehabilitated areas m expected numbers. It was hypothesized that Phytophthora cinnamomi Rands and Phytophthora citricola Sawada, which had been recovered from soil and diseased vegetation in the pits may have been reducing establishment of these species. This project aimed to determine whether P . cinnamomi and P. citricola could cause damping-off of native plant species in bauxite pit rehabilitation. To achieve this aim five preliminary experiments, followed by a glasshouse experiment and an experiment based in a rehabilitated bauxite pit, were undertaken. The preliminary glasshouse and laboratory experiments determined mean percentage germination, as well as isolating seed testa fungi, for six native plant species identified as not returning in expected numbers to the rehabilitation. The plant species chosen were Clematis pubescens Huegel ex Endl., Cyathochaeta avenacea Benth., E. marginata. H akea lissocarpha R.Br., H ovea chorizemifolia (Sweet) DC. and Xanthorrhoea preissii Endl. Soil from rehabilitated pits was also shown to not cause suppression of P. cinnamomi and P. citricola. An appropriate density of millet seed for use in the main glasshouse experiment was determined and the process of soil solarization was investigated to determine whether it could be used to eradicate phytophthora species from soil in rehabilitated bauxite pits. The method of soil solarization used in this project was found to not be effective in eradicating Phytophthora species from the rehabilitated areas. The two main experiments tested the pathogenicity of P . cinnamomi and P. citricola on seed and seedlings of the six native plant species chosen for this study, in the glasshouse and rehabilitated bauxite pit environments. Both P. cinnamomi and P. citricola were found to cause post-emergent damping-off of E. rna r gina ta in the glasshouse, with P. cinnamomi also causing damping-off of X. preissii seedlings in this environment. An introduced isolate, as well as indigenous isolates of P. citricola caused pre and post-emergent damping-off of E. marginata in the field. P. citricola also caused pre-emergent damping-off of H. lissocarpha in the rehabilitated trial areas. The P. cinnamomi inoculum did not cause disease in the field due to sub-optimum ambient temperatures which inhibited sporangia! formation and mycelial growth (Shearer and Tippett, 1989). However, P. cinnamomi has been shown to cause damping-off in regenerating areas (Mwanza and Kellas, 1987) and probably causes damping-off in Alcoa's rehabilitated areas when conditions are more favourable, in autumn and spring. P. cinnamomi and P. citricola therefore probably reduce the biodiversity of Alcoa's rehabilitated pits by reducing the establishment of susceptible species. Topics requiring further research are discussed.

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au, D. Huberli@murdoch edu, and Daniel Huberli. "Phenotypic variation of two localised populations of Phytophthora cinnamomi from Western Australia and how they impact on Eucalyptus marginata resistance." Murdoch University, 2001. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20070827.91902.

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Phytophthora cinnamomi is an introduced soilborne phytopathogen to Western Australia (WA) and impacts on 2000 of the approximately 9000 plant species indigenous in the southwest of WA. Amongst these is Eucalyptus marginata (jarrah), the dominant and economically important hardwood timber species of the jarrah forest. This thesis aimed to investigate the morphological, pathogenic and genotypic variation in two local WA populations of P. cinnamomi isolates. The populations were selected from areas where jarrah clonal lines selected for resistance to P. cinnamomi may be used in the rehabilitation of infested jarrah forest and rehabilitated bauxite minesites in the southwest of WA. Resistance against a range of isolates using different inoculation methods. Seventy-three isolates of P. cinnamomi were collected from diseased jarrah and Corymbia calophylla (marri) trees from two populations located 70 km apart and these were examined for phenotypic and genotypic variation. Microsatellite DNA analysis showed that all isolates were of the same clonal lineage. In P. cinnamomi for the first time I show that there is a broad and continuous variation in the morphology and pathology between two populations of one clonal lineage, and that all phenotypes varied independently from one another. No relationship was found between morphological and pathogenic characters. The ability of isolates in both populations to cause deaths ranged from killing all plants within 59 days to plants being symptomless 182 days after inoculation. Single and multiple paragynous antheridia formed along with amphigynous ones in mating studies with all WA isolates and a sample of worldwide isolates. Developmental studies and cytological examination showed fertilisation tubes developed asynchronously or synchronously from both antheridial types and indicated that either antheridial type contributed a nucleus for fertilisation of the oosphere. This is the first report of paragynous antheridial associations in P. cinnamomi. Antheridial variation is a characteristic that needs to be adjusted in the taxonomic Phytophthora identification keys. In underbark and zoospore stem inoculations of three 1.5-year-old jarrah clonal lines (two ranked as resistant (RR) and one as susceptible (SS) to P. cinnamomi in the original selection trials) at 15, 20, 25 and 30°C, it was found that the method of inoculation did not produce comparable results, particularly at 25 and 30°C. At these temperatures, all three clonal lines had 100% mortality when inoculated underbark, but when inoculated with zoospores, one RR line had 60% survival and the SS and remaining RR line had 100% mortality. Generally, the level of resistance of all clonal lines declined with increasing temperature. Lesion development was measured at 20, 25 and 30°C for 4 days in detached branches of an RR and SS clonal line inoculated underbark with four different P. cinnamomi isolates. Detached branches were found to be a potential screen for jarrah resistance to P. cinnamomi and to allow the identification of susceptible and resistant clonal lines at 30°C. Lesion and colonisation development of P. cinnamomi isolates were assessed in situ (late autumn) of seed-grown and clonal lines of 3.5 to 4.5 year-old jarrah trees growing in a rehabilitated minesite jarrah forest in underbark inoculation of lateral branches (1995) or simultaneously in lateral branches and lateral roots (1996). Trees were underbark inoculated in lateral branches and lateral roots. Colonisation was more consistent as a measure of resistance than lesion length over the two trials because it accounted for the recovery of P. cinnamomi from macroscopically symptomless tissue beyond lesions, which on some occasions, was up to 6 cm. In the two trials, one RR clonal line consistently had small lesion and colonisation lengths in branches and roots. In contrast, the remaining two RR clonal lines had similar lesion and colonisation lengths to the SS clonal line and may, therefore, not be suitable for use in the rehabilitation of P. cinnamomi infested areas. The relative rankings of the jarrah clonal lines by colonisation lengths were similar between branch and root inoculations. Branch inoculations are a valid option for testing resistance and susceptibility of young jarrah trees to P. cinnamomi. The pathogen was recovered on Phytophthora selective agar 36 months after inoculation from 50% of samples with lesions and 30% of symptomless samples in a series of growth cabinet, glasshouse and field experiments. However, up to 11% of samples with and without lesions and from which P. cinnamomi was not initially isolated contained viable pathogen after leaching the plant material in water over 9 days. This indicates that the pathogen could be present as dormant structures, such as chlamydospores, where dormancy needs to be broken for germination to occur, or fungistatic compounds in the tissue need to be removed to allow the pathogen to grow, or both. These results have important implications for disease diagnosis and management, disease-free certification and quarantine clearance. No clonal line of jarrah was found to be 100% resistant using different inoculation methods, environmental conditions and when challenged by individuals from a large range of P. cinnamomi isolates. Even the most promising RR line had individual replicates that were unable to contain lesions or died with time. This suggests that further screening work may be required using more isolates varying in their capacity to cause disease and a broader range of environmental conditions. Jarrah clonal lines that survive such rigorous screening could then be expected to survive planting out in a range of environments in the jarrah forest and rehabilitated bauxite minesites.

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Ruprecht, John. "Impact of forest disturbance on jarrah (Eucalyptus marginata) forest hydrology." Thesis, Ruprecht, John (2018) Impact of forest disturbance on jarrah (Eucalyptus marginata) forest hydrology. PhD thesis, Murdoch University, 2018. https://researchrepository.murdoch.edu.au/id/eprint/40880/.

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Globally, forests cover 31% of the Earth’s land mass and are critical areas for water supply. In Australia, forested catchments provide 77% of urban water supplies to capital cities. However, recent studies have reported worldwide examples of forest damage resulting from drought or heat related events. The jarrah (Eucalyptus marginata) forests of south-west Western Australia (SWWA) have experienced both sudden and unprecedented forest collapse and profound reductions in streamflows. Projected further declines with climate change, reinforce the need to understand the hydrologic impact of forest disturbance and what management responses are needed to enhance forest resilience and productive capacity. The aim of this thesis was to understand the impact of disturbance and climate on the hydrology of the forests of SWWA, with objectives to: 1. Examine the characteristics of forest hydrology; 2. Evaluate the hydrologic response to forest disturbance and climate variability; and 3. Evaluate forest water management options in the context of forest disturbance and climate change. This thesis thus develops an understanding of the impact of disturbance and climate on the hydrology of the forests of SWWA. Using hillslope and paired catchment studies (Chapter 3), it develops an understanding of the process of infiltration and soil water dynamics and examines the hydrologic impact of forest disturbance. The studies demonstrate the important roles of infiltration, soil water dynamics, and groundwater on the forest water balance, and identify the major factors that impact forest disturbance and forest hydrology. These studies have improved understanding of factors contributing to catchment water balance, and streamflow generation processes. Four catchments underwent land use change and the impact on catchment hydrology was studied by comparing with a control catchment (Chapter 4). These paired catchment studies evaluated the impact of converting forest to agriculture and of timber harvesting. They explored the streamflow generation mechanisms for forested and cleared catchments, the streamflow generation and salinity export changes due to clearing for agriculture, and the hydrologic impact of intense timber harvesting for increased water production. The impacts of deforestation, forest thinning, bauxite mining, bushfires, dieback disease, and reforestation were evaluated using several paired catchment studies across SWWA (Chapter 5). The long-term implications for management of water yield, the impact of a range of disturbances at a catchment scale, and the impact of forest disturbances on stream salinity are also examined. The relationship between the drying climate observed in SWWA over the last 40 years and observed changes in rainfall, groundwater levels, streamflow volumes and flow duration were studied in Chapter 6. The changing relationship between rainfall and streamflow and the likely implications of recent climate change scenarios are also studied. The major forest water issues that have been identified in this thesis are the declining water values in forested areas, such as less water volumes, shorter flow periods, and declining groundwater levels. The adaptive strategies for forest ecosystems are identified to include resistance (protect highly valued areas), resilience (improve capacity to return to pre-disturbance conditions) and response (assist transition to new condition) are discussed in Chapter 7. Drivers identified (Chapter 7) by this thesis include (a) a drying climate with direct and indirect impacts on both the forest itself and on the overall water balance, (b) responses to historical forest management including forest harvest, deforestation and reforestation, (c) long-term impacts of bauxite mining and subsequent rehabilitation, and (d) the interaction of these forest disturbances at a catchment scale. The major findings from this study include: - The high saturated hydraulic conductivity of the sandy gravel topsoil overlies lateritic durcirust with a much lower saturated hydraulic conductivity; - The presence of large infilled “holes” within the lateritic duricrust; - Saturation above the lateritic duricrust was observed confirming subsurface flow concepts; - Presence of vertical preferential flow observed confirming soil water concepts; - The critical importance of the groundwater discharge area in streamflow generation; - Increase in stream salinity directly linked to groundwater levels approaching the surface; - The time to leaching of the salt from the catchment estimated at 200 years; - Forest disturbances such as clearing, timber harvesting and forest thinning led to increased streamflow but with significant delays related to the presence or lack of a groundwater discharge area; and - The extensive reduction in streamflow across the south west has ranged from 36 to 52% (1975 to 2000 compared to 2001 to 2012) seen as a delayed response to rainfall reductions from 1930 to 2000. The challenge for the future is for forest hydrology research to influence current and future forest management to improve environmental and water supply outcomes for the forests of not only SWWA, but globally. Understanding the impact of land-use change on hydrology, water quality and on water resources, and separating this from climate variability and change, is a recurring problem globally. Further understanding is thus needed of the causes of changing forest hydrology and of management options to ultimately improve forest outcomes.

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Mercier, Angela. "Home range and microhabitat selection by Tiliqua rugosa and Egernia napoleonis in the native jarrah forest and rehabilitated mined areas in jarrah forest of Western Australia." Thesis, Mercier, Angela (2006) Home range and microhabitat selection by Tiliqua rugosa and Egernia napoleonis in the native jarrah forest and rehabilitated mined areas in jarrah forest of Western Australia. Honours thesis, Murdoch University, 2006. https://researchrepository.murdoch.edu.au/id/eprint/32754/.

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The present study examined the home range and microhabitat selection by Tiliqua rugosa and Egernia napoleonis in the jarrah forest of southwest Western Australia. The aim of the study was to compare the microhabitats used by T. rugosa with the microhabitats used by E. napoleonis and discuss why T. rugosa was located in rehabilitated bauxite mined areas, whereas E. napoleonis was not. The overall objective of the present study was to identify methods which may be incorporated into the management of rehabilitated bauxite mined areas operated by Alcoa World Alumina Australia, to accelerate the return of T. rugosa and E. napoleonis. A total of five Tiliqua rugosa and eight Egernia napoleonis were radio tracked from October 2005 until January 2006. The 100% home range average of T. rugosa was significantly larger than that of E. napoleonis. There was no significant difference in 50% Core home range average between the two species. The home range of T. rugosa was made up of native jarrah forest and rehabilitated mined areas. E. napoleonis were only found in native jarrah forest. The microhabitats significantly selected by Tiliqua rugosa in the native jarrah forest and rehabilitated mined areas were shrubs and leaf litter. In the native jarrah forest spikey and dome-shaped shrubs were significantly selected, but when in the rehabilitated mined areas spikey shrubs were significantly selected, which was probably due to the scarcity of dome-shaped shrubs in the rehabilitated areas. The selected microhabitats of Egernia napoleonis were logs and trees. The Eucalyptus marginata logs selected by Egernia napoleonis had a mean diameter of 42 ± 2lcm, whilst the Corymbia calophylla logs had a mean diameter of 48 ± 6cm. E. napoleonis did not differentiate between tree species of log. Common characteristics of logs selected by E. napoleonis were the presence of cracks, hollows, and some degree of fire damage. In the present study no logs were located in rehabilitated mined areas. The trees selected by Egernia napoleonis were significantly larger than a random selection of those found in native jarrah forest or those found in rehabilitated mined areas. Eucalyptus marginata selected by E. napoleonis had an average diameter at breast height of 73 ± 16cm whilst Corymbia calophylla had an average diameter at breast height of 58± 15cm. Species of tree were not differentiated by E. napoleonis. Both microhabitat structures (logs and large trees) selected by Egernia napoleonis were unable to be located in rehabilitated mined areas. The spikey shrubs and leaf litter microhabitats selected by Tiliqua rugosa were present in native jarrah forest and rehabilitated mined areas. The present study has shown that a lack of suitable microhabitats was reducing the occurrence of E. napoleonis in rehabilitated mined areas. Methods to help rectify this problem are discussed.

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Steel, Emma. "Drought-associated heatwaves: Consequences for vegetation of the Northern Jarrah Forest." Thesis, Steel, Emma ORCID: 0000-0002-2299-3408 (2018) Drought-associated heatwaves: Consequences for vegetation of the Northern Jarrah Forest. PhD thesis, Murdoch University, 2018. https://researchrepository.murdoch.edu.au/id/eprint/41473/.

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Worldwide, extreme climatic events such as drought and heatwaves are associated with forest mortality. While many studies address the immediate impacts of forest die-off events, information about the ongoing structural and compositional consequences is lacking. The Northern Jarrah (Eucalyptus marginata) Forest of southwestern Australia experienced a severe tree die-off event during a drought-associated heatwave. Using transects spanning a gradient of drought impacts (severe, transitional, minimal), tree species mortality in relation to soil depth and stand condition (stand basal area, stem density) was quantified. Differential mortality was exhibited by the two dominant overstorey species and two midstorey tree species, which occurred in distinct zones along the transects. The dominant, structural forest species Eucalyptus marginata (jarrah), had higher mortality than the co-dominant Corymbia calophylla and midstorey species Allocasuarina fraseriana. The midstorey tree (Banksia grandis) exhibited the highest stem mortality and a substantial shift in structure in response to the drought-associated heatwave in relation to tree size, soil depth and stand basal area. Banksia grandis represents a drought intolerant species. Regeneration of tree species was surveyed over three years and was greater in areas of high drought-impact than in healthy forest. To determine the response of understorey communities to the droughtassociated heatwave and subsequent changes in forest canopy, the abundance, composition and structure of understorey species was compared among drought-impact zones. In areas of high drought-impact, understorey communities showed different species assemblages and higher richness and cover than in healthy forest. The recovery of tree canopy following the event was studied by examining the temporal response of Eucalyptus marginata (jarrah) trees in zones of drought-impact and healthy forest using dendrometer bands. Trees growing in the high drought-impact zone had greater stem-diameter growth than trees in adjacent healthy forest. This study provides valuable insights into the consequences of a droughtassociated heatwave in driving structural and compositional changes in jarrah forest vegetation and highlights the importance of studying all components of the vegetation following forest mortality events

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Burgar, Joanna. "Bat habitat use of restored jarrah eucalypt forests in south-western Australia." Thesis, Burgar, Joanna (2014) Bat habitat use of restored jarrah eucalypt forests in south-western Australia. PhD thesis, Murdoch University, 2014. https://researchrepository.murdoch.edu.au/id/eprint/24229/.

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Restoration is an important tool in conserving biodiversity, yet passive faunal recolonisation may take decades, or longer, to occur. This is of particular conservation importance in biodiversity hotspots, such as south@western Australia, which are experiencing increasing fragmentation and rapidly drying climates. Within this hotspot, I investigated the response of nine insectivorous tree@dwelling bat species to restored mine@pits in jarrah (Eucalyptus marginata) forests. I assessed bat activity in restored, relative to unmined, forests and the suitability of restoration as foraging and roosting habitat. Bat echolocation call surveys measured bat activity in varying ages of restoration and unmined forest across two years (2010@2012) during both maternity and mating seasons. Although all bat species were detected in both forest types, restored mine@pits of all ages had significantly different bat communities and lower overall activity compared to unmined forest. Habitat filters to bat use of restoration were evident for the more manoeuvrable bat species and were predominantly related to midstorey forest structure. Tree density was the most important predictor of bat use of restoration for less manoeuvrable bat species. To determine the suitability of restored forest as foraging habitat I investigated the diet of three species (Chalinolobus gouldii, Nyctophilus gouldi and Vespadelus regulus) over maternity and mating seasons (2010/2011) by examining prey remains in faecal samples. I used high@throughput sequencing and bioinformatics analyses to phylogenetically group prey DNA and found that niche partitioning occurred, with dietary divergence positively related to bat ecomorphological divergence. In addition, I assessed the foraging potential of restored forest and found that prey occurrence did not necessarily equate to prey accessibility for all bat species. There was a synergistic effect of vegetation structure and insect biomass for edge foraging bat species. To determine the suitability of restoration as roosting habitat I used telemetry to radio@track 36 bats from two species (N. gouldi and V. regulus) to 59 distinct roosts. Not one bat was found roosting in restored forest and individuals preferred roosting in mature, tall trees in intermediate to late stages of decay. My research clearly shows that restored forest does not yet provide suitable foraging or roosting habitat for all jarrah forest bats. Improving habitat suitability through management manipulations, such as thinning and burning, may accelerate bat recolonisation of restored forest. In the interim, retention of mature forest patches is necessary for conserving and maintaining bat populations across restored landscapes.

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Rhind, Susan Gaye. "Ecology of the brush-tailed phascogale in jarrah forest of southwestern Australia." Thesis, Rhind, Susan Gaye (1998) Ecology of the brush-tailed phascogale in jarrah forest of southwestern Australia. PhD thesis, Murdoch University, 1998. https://researchrepository.murdoch.edu.au/id/eprint/52136/.

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This study investigated the ecology of the marsupial brush-tailed phascogale (Phascogale tapoatafa; phascogale) in jarrah forest of Western Australia (WA). The thesis provides a descriptive account of the species' population dynamics, the phascogale’s size and growth, foraging ecology and nesting behaviour. The main work was undertaken between 1992-1995 and information was gathered by capture and by using radiotelemetry. The availability of food sources and refuge sites was examined and the species' immediate response to a logging operation was investigated. On a broader scale, the taxonomy of phascogales in WA was reviewed and their past and present distributions were explored by modelling and examination of museum records. The species has previously been subject to only one detailed study and this was undertaken in the State of Victoria. Both similarities and differences were observed between the phascogales in WA and Victoria. Many of the differences appeared to have a nutritional basis. Phascogales are primarily arboreal insectivores and some of the invertebrates most commonly found in scats and stomachs were not abundant on trees. Nectarivory was very rarely observed (cf. Victoria). While phascogales are generalists in diet, they clearly show preferences for certain foods. The strongly seasonal climate in the southwest (long dry summers and wet winters) and the lack of diversity in tree species and low nectar availability probably limit food for WA phascogales. The dispersed nature of tree invertebrates and the apparent scarcity of some preferred prey, such as beetles, possibly explain the exclusive and often large size of female territories. Phascogales in the study area were smaller and less sexually dimorphic than those in Victoria. Males were 30%, and females 20%, less in weight than those in Victoria. They were similarly smaller in skeletal size. Overall size was also found to vary' between habitat type and between years. In a year of drought phascogales did not achieve typical body size with mature males in that year weighing an average 25% less than usual. The evidence strongly suggests that annual and local availability of food is a major determinant of body size and growth. Such variability in food availability may also be the evolutionary basis behind the litter sizes of WA phascogales. These are smaller than those in Victoria (mode WA = 6, Victoria = 8). The timing of major life-history events was as described for Victorian phascogales, although births occur a little later in the year. All males died at the end of the single annual breeding season (male semelparity) and young took some five to six months to raise to weaning. Some females survived to breed in a second year but the number encountered was low. The toll of lactation probably reduces lifespan and females were often in poor condition at late lactation and maximum maternal effort appears selectively invested in the first litter. Typical of the semelparous species, females initially tried to raise as many young as they have teats. However, there was variation in litter sizes among females. The basis for this was anatomical as females had six, seven or eight teats. Such variation occurred throughout the study area, within litters and appears a State-wide phenomenon. Except in a hybrid Antechinus population, there appears to be no marsupial precedent for intrapopulation and intralitter variation in teat number. In such a strongly selected trait, it is speculated that such variation could only persist if the environment was spatially and/or temporally unstable in terms of food availability. There was no evidence that reduction in teat number was a direct trade-off that improved the chance of surviving to breed on a second occasion, but data were limited. The teat trait is presumably under genetic control and the promiscuous mating behaviour of phascogales may contribute, via multiple paternity, to the intralitter variability observed. In the year of drought litters were significantly female biased. Neither sex were sexually dimorphic until they began foraging for themselves, therefore such bias was unlikely to reduce maternal stress during the drought conditions. The adaptive advantage of the bias was undetermined, but current literature indicates that such bias occurs at conception. However, female offspring probably have better post-weaning survival than males. Examination of refuge requirements showed that natural nest sites were located in tree hollows. The profile of the trees chosen agree with most studies on hollow-nesting species. There was no apparent preference for particular tree species but there was a preference for nesting in older and senescent or dead trees. Females with dependent young showed particular preference for these trees' forms. However, once a tree was used, no tree characteristics measured were predictors of the tree being used on further occasions. Excluding females with young, phascogales typically spent 2-5 days nesting in the one refuge before moving to another. Females moved between alternative refuges more than males and home range maintenance is proposed to account for the difference (males were not territorial cf. females). For both sexes, parasite avoidance might account for the generally low level of nest-site fidelity. Individuals were estimated to use around 27 (males) and 38 (females) different nest-sites during one year of adult life. The parameters of hollows examined showed a preference for using hollows with small entrances. More than predator avoidance, interspecific competition for hollows may explain such selectivity. Following the year of drought, communal nesting was common in autumn and winter. This was in marked contrast to data gathered early in the study and to the nesting behaviour of Victorian phascogales. Communal nesting was probably an energy conserving strategy adopted to compensate for unusually small body size. This behaviour may have been a single year event. However, as phascogales in the area are normally much smaller in body mass than those studied in eastern Australia, they may tend to nest communally in winter or when under conditions of hardship. The immediate response of phascogales to logging was examined. Those affected continued to travel through and feed in the logged areas, which reinforces the concept of high site fidelity among animals. Phascogales were commonly found feeding among ground debris in cut areas indicating flexibility in foraging mode. With rare exceptions they ceased nesting in trees in the logged parts of their territories and confined such nesting to surrounding uncut forest. This suggests that the forestry practice of retaining a select number of hollow-bearing trees/ha may be insufficient to meet the species' refuge requirements in logged areas. Of concern is that currently unlogged sections in logged forest can be cut within 10-20 years yet trees take some 200 years to develop hollows. Additionally, the value of young regrovvth as a food source to this species is questionable. The study highlights the concerns that many scientists have regarding the preservation of hollow-nesting fauna in areas that are impacted by logging. A revision of the species taxonomy (including the subspecies P. t. pirata) indicates that southern WA phascogales warrant subspecies status. Differences in basiacranial features were found between the regional groups in Australia. However, the issue of long-term geographic and reproductive isolation is perhaps the greater argument for suggesting subspecific status for WA phascogales. This is currently being examined using mitochondrial DNA techniques. This will provide not only a DNA profile of similarities and presumed differences between WA and southeastern phascogales, but will give an estimation of the time that the two groups have been separated. A modelling exercise undertaken to examine the potential past distribution of WA phascogales showed that climatic conditions favourable to this species are found throughout the southern part of WA. For many of these areas there are no records of phascogales although a single historical work (1909) indicated that they were present in these areas. At that time they were apparently already extinct in some areas and dying out in others. A survey of the northern jarrah forest and a few other areas (by using nestboxes) failed to detect phascogales. The population examined during this study was therefore quite unusual in density, as phascogales were readily found in nestboxes. A myriad of factors culminating in low feral predation in the area seems the most likely explanation for the high densities observed. The conservation status of phascogales in areas other than the study region requires examination. Predation by exotic predators might account for the species' rarity, but food appears a generally limiting factor for phascogales and processes that alter habitat productivity may significantly impact this species.

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Lucas, Anne. "Water stress and disease development in Eucalyptus marginata (jarrah) infected with Phytophthora cinnamomi." Thesis, Lucas, Anne (2003) Water stress and disease development in Eucalyptus marginata (jarrah) infected with Phytophthora cinnamomi. PhD thesis, Murdoch University, 2003. https://researchrepository.murdoch.edu.au/id/eprint/167/.

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The south-west of Western Australia has a Mediterranean climate and flora endemic to this area, including the keystone species, jarrah (Eucalyptus marginata), have adapted to the droughted summer conditions. The introduction of an exotic soil borne pathogen, Phytophthora cinnamomi, has challenged the survival of this and many other species. The expectation might be that plants stressed by drought are more susceptible to disease and this study examined the development of disease caused by P. cinnamomi in E. marginata and the significance of water status to that development. Seedlings of E. marginata, clonal plants resistant to P. cinnamomi and clonal plants susceptible to P. cinnamomi, were subjected to different watering regimes in a number of field and glasshouse experiments. To determine the level of drought stress that could be imposed on container-grown E. marginata seedlings without killing them, a preliminary experiment progressively lowered the moisture levels of the substrate in their containers, until the plants reached wilting point, at which time moisture was restored to a predetermined droughted level and the process repeated. With each subsequent droughting the wilting point was lower until it was found that the seedlings could survive when only 5% of the moisture lost from container capacity to wilting point was restored. No deaths had occurred after seedlings had been maintained at this low level for 14 days (Chapter 2). Based on these findings, the level of droughting maintained in all experiments conducted under controlled glasshouse conditions was 10% restoration. After testing the appropriateness of underbark inoculation, and a zoospore inoculation method for which no wounding was necessary, a new, non-invasive stem inoculation technique was developed. Stems were moistened in a pre-treatment, then agar plugs colonized with P. cinnamomi mycelium were held against the stem with wads of wet cotton wool and bound in place with tape. This technique resulted in a high proportion of infection in E. marginata (Chapter 4) without the need for underbark inoculation or the use of zoospores (Chapter 3). It was successfully used in a large field trial in a rehabilitated bauxite mine site with 2-year-old E. marginata clonal plants, resistant to P. cinnamomi (Chapter 5). Inoculation was in late spring after the winter and spring rainfall. This timing was to allow comparison of disease development in stressed plants under normal droughted summer conditions compared with itsdevelopment in non-stressed, irrigated plants. However, two months after inoculation, the area was deluged with unseasonal and abnormally heavy summer rainfall, negating any difference in the treatments and causing an outbreak of P. cinnamomi in the soil from an adjacent infested site. This resulted in the infection and death of some noninoculated control clones. Monitoring of the site continued for twelve months and the advance of P. cinnamomi at the site was mapped. To test the effect of drought on the expression of P. cinnamomi under more controlled conditions, a series of glasshouse experiments was set up that simulated two possible summer conditions; drought or drought followed by abnormally high summer rainfall. These experiments utilised E. marginata seedlings and clonal plants, some resistant and some susceptible to P. cinnamomi. Plants were inoculated with P. cinnamomi prior to or after droughting. Results were compared to those of control plants that had not experienced water deficit. In both seedlings and clonal plants, the greatest extent of colonization was found in plants which had experienced no water deficit. These results indicated that drought stress played a role in inhibiting the in planta development of P. cinnamomi in all genotypes (Chapter 8). This finding was consistent for both clones, susceptible and resistant to P. cinnamomi. Most recoveries were made from non-stressed clonal plants, resistant to P. cinnamomi (Chapter 6) and more colonization was found in non-stressed clonal plants, susceptible to P. cinnamomi (Chapter 7), than was recorded for droughted plants. The results of the field trial showed that P. cinnamomi was not recovered from some inoculated stems, which had obvious lesions, when segments were plated onto selective agar. This led to an intensive in vitro investigation into improved methods of recovery. Dark brown exudates from some segments of inoculated stems stained the surrounding agar onto which they were plated, suggesting the presence of phenolic compounds. Recovery of the pathogen from stems increased by about 10% when segments were first soaked in distilled water to leach out the phenolic compounds, then replated onto agar. Other recovery methods were also tested, including (1) baiting with Pimelea ferruginea leaves floated on the surface of water or soil filtrate, in which the infected stem segments were immersed and (2) the application of different light and temperature regimes. It was clearly shown that exudates from infected stems of field grown E. marginata inhibited the outgrowth of P. cinnamomi onto the agar. To counter the possible toxic effect that oxidized phenolics had on the growth of the P. cinnamomi, an antioxidant was added to the agar. P. cinnamomi was grown on media whichincorporated exudates from infected stems and different concentrations of ascorbic acid, with and without adjusted pH levels. There was a pronounced pH effect, with less growth on media with lower pH and no significant increase in growth of the mycelium with increased ascorbic acid concentration on pH adjusted agar (Chapter 9). The inhibitory effect of the exudates from the stem segments led to an investigation of the possibility that, if seedlings to be planted in the rehabilitation process could be pre-treated with phenolic compounds to render them more resistant, they may have an advantage when establishing in areas where there was a potential threat of P. cinnamomi. E. marginata seeds were germinated and the seedlings grown hydroponically in a constant temperature growth room. Different concentrations of synthetic catechol, a phenolic compound naturally occurring in E. marginata, were added to the nutrient solution. Roots remained immersed in the catechol solutions for three days, before being inoculated at the root tip with zoospores of P. cinnamomi. Roots in higher concentrations of catechol were less colonized than those in lower concentrations, indicating an increased resistance to the pathogen (Chapter 10). Further work is required to determine if seedlings treated before being planted in areas threatened by an outbreak of P. cinnamomi have a greater capacity for survival, and for how long the protection persists. The improved recovery of P. cinnamomi from infected plants is important for accurate assessment of the spread of the disease in an area and for the subsequent implementation of management strategies of containment and control. An outbreak of P. cinnamomi can impact on the revegetation of rehabilitated mine sites and the aetiology of the pathogen in mine sites needs to be more fully understood. The interaction of plant defences with the invasive pathogen has been examined in a range of environments in the field, the glasshouse, in a hydroponics system and in vitro. The results indicate that summer droughting increases the resistance of E. marginata to P. cinnamomi. However, more work is required to understand the mechanisms involved. The study also indicates that clones of E. marginata, selected as resistant to P. cinnamomi, are not resistant under all conditions and that environmental interactions should be further investigated. Lastly, for effective management strategies to be implemented it is critical that the pathogen can be confidently isolated from plants. It was shown that exudates from infected hosts inhibit the recovery of P. cinnamomi. Recovery methods that can overcome these inhibitory compounds are required. The findings invite further research into the complexity of host-pathogen relationships.

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Lucas, Anne. "Water stress and disease development in Eucalyptus marginata (jarrah) infected with Phytophthora cinnamomi." Murdoch University, 2003. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20040820.13290.

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Collins, Sarah. "Long-term survival of Phytophthora cinnamomi in rehabilitated bauxite mines and adjacent jarrah." Thesis, Collins, Sarah (2006) Long-term survival of Phytophthora cinnamomi in rehabilitated bauxite mines and adjacent jarrah. PhD thesis, Murdoch University, 2006. https://researchrepository.murdoch.edu.au/id/eprint/32426/.

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Luxton, Sarah Jayne. "Modelling refugia for improved conservation outcomes in the northern jarrah forest, southwestern Australia." Thesis, Curtin University, 2020. http://hdl.handle.net/20.500.11937/84066.

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Watson, Alexander William Thomas. "A comparison of logging and fire disturbance on biophysical attributes of the northern jarrah forest." Connect to thesis, 2006. http://portal.ecu.edu.au/adt-public/adt-ECU2006.0041.html.

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Bunny, Felicity J. "The biology, ecology and taxonomy of Phytophthora citricola in native plant communities in Western Australia." Thesis, Bunny, Felicity J. (1996) The biology, ecology and taxonomy of Phytophthora citricola in native plant communities in Western Australia. PhD thesis, Murdoch University, 1996. https://researchrepository.murdoch.edu.au/id/eprint/492/.

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The objectives of the project were to develop an understanding of the disease dynamics caused by Phytophthora citricola in native plant communities in the south of Western Australia. Prior to 1983, the pathogen had only been reported twice from Australian forests. Since then, P. citricola has been extensively recorded from plant communities north and south of Perth, and is currently the second most frequently recovered Phytophthora species from the northern jarrah forest and the northern sandplains. The objectives were addressed by examining the biology, ecology and taxonomy of isolates of P. citricola local to the southwest. Examination of the intraspecific variation of P. citricola by isozyme analysis resolved three major electrophoretic subgroups (SG), and these were aligned with morphological and cultural variation within the species. One electrophoretic SG was confined to forested areas. This SG differed from other SGs in sporangial dimensions, growth rate on two media and in vitro sensitivity to phosphonate. A redescription of the species may be warranted. P. citricola was positively associated with two roads in the northern jarrah forest. Road surfaces were sampled, then soil overburden was removed and the surface of the concreted lateritic layer beneath was sampled. Isolation of P. citricola declined away from the road into the adjacent forest and was more frequently recovered from the caprock (up to 1 metre below soil surface) than from the soil surface. The most probable source of introduction was from infested soil on vehicles using the roads. Oospores were shown to be produced in two soils, a lateritic gravelly loam and sand, and in plants. In soil, the electrophoretic SG confined to the forest (loamy soil) produced only limited numbers of oospores in the sandy soil of the northern sandplain. The restriction of this SG to the forested areas is probably physiological, rather than limited dispersal, with the SG currently occupying the full extent of its range. Estimation of the relative persistence of oospores, zoospores and plant material colonised by P. citricola established that only oospores (either free in soil or in colonised plant material) were important in long tern survival in soil. Oospores were still viable after six months at two field sites, and after 18 months in soil in the laboratory. Phosphonate is currently the most promising method of control of Phytophthora induced disease in native plant cornmunites of the southwest. The efficacy of phosphonate against P. citricola was examined in vivo and in vitro against two SGs. Phosphonate successfully inhibited lesion growth of both SGs in vivo, but of only one electrophoretic subgroup in vitro. The ecological implications of infestation of native plant communities in the southwest of Australia are discussed.

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Bunny, Felicity J. "The biology, ecology and taxonomy of Phytophthora citricola in native plant communities in Western Australia." Murdoch University, 1996. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20061122.122739.

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The objectives of the project were to develop an understanding of the disease dynamics caused by Phytophthora citricola in native plant communities in the south of Western Australia. Prior to 1983, the pathogen had only been reported twice from Australian forests. Since then, P. citricola has been extensively recorded from plant communities north and south of Perth, and is currently the second most frequently recovered Phytophthora species from the northern jarrah forest and the northern sandplains. The objectives were addressed by examining the biology, ecology and taxonomy of isolates of P. citricola local to the southwest. Examination of the intraspecific variation of P. citricola by isozyme analysis resolved three major electrophoretic subgroups (SG), and these were aligned with morphological and cultural variation within the species. One electrophoretic SG was confined to forested areas. This SG differed from other SGs in sporangial dimensions, growth rate on two media and in vitro sensitivity to phosphonate. A redescription of the species may be warranted. P. citricola was positively associated with two roads in the northern jarrah forest. Road surfaces were sampled, then soil overburden was removed and the surface of the concreted lateritic layer beneath was sampled. Isolation of P. citricola declined away from the road into the adjacent forest and was more frequently recovered from the caprock (up to 1 metre below soil surface) than from the soil surface. The most probable source of introduction was from infested soil on vehicles using the roads. Oospores were shown to be produced in two soils, a lateritic gravelly loam and sand, and in plants. In soil, the electrophoretic SG confined to the forest (loamy soil) produced only limited numbers of oospores in the sandy soil of the northern sandplain. The restriction of this SG to the forested areas is probably physiological, rather than limited dispersal, with the SG currently occupying the full extent of its range. Estimation of the relative persistence of oospores, zoospores and plant material colonised by P. citricola established that only oospores (either free in soil or in colonised plant material) were important in long tern survival in soil. Oospores were still viable after six months at two field sites, and after 18 months in soil in the laboratory. Phosphonate is currently the most promising method of control of Phytophthora induced disease in native plant cornmunites of the southwest. The efficacy of phosphonate against P. citricola was examined in vivo and in vitro against two SGs. Phosphonate successfully inhibited lesion growth of both SGs in vivo, but of only one electrophoretic subgroup in vitro. The ecological implications of infestation of native plant communities in the southwest of Australia are discussed.

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Davis, Christine. "The importance of dead jarrah (Eucalyptus marginata) stags as microhabitat for arboreal lizards (Cryptoblepharus plagiocephalus an Christinus marmoratus) in rehabilitated bauxite mine-pits and native jarrah forest of south-west Western Australia." Thesis, Davis, Christine (2006) The importance of dead jarrah (Eucalyptus marginata) stags as microhabitat for arboreal lizards (Cryptoblepharus plagiocephalus an Christinus marmoratus) in rehabilitated bauxite mine-pits and native jarrah forest of south-west Western Australia. Honours thesis, Murdoch University, 2006. https://researchrepository.murdoch.edu.au/id/eprint/32752/.

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The marbled gecko (Christinus mannoratus) and wall skink (Cryptoblepharus plagiocephalus) are two arboreal lizards known to use dead stags in the jarrah forest of south-western Australia. Both these species are abundant in un-mined jarrah forest. However, the marbled gecko and to a lesser extent the wall skink are failing to return to areas rehabilitated following mining by Alcoa World Alumina Australia. The reason for this is thought to be the absence of dead stags, as dead stags can provide an important habitat component to arboreal lizards as a foraging substrate to hunt insect prey and also a place in which to shelter (cracks and hollows). The present study examined the microhabitat available to arboreal lizards in rehabilitated mine-pits at Alcoa's Huntly mine-pit (~lOOkm SE of Perth) and in adjacent un-mined jarrah forest, as well as determining the size and senescence of trees used by the two study species. It was found that in un-mined jarrah forest live trees regardless of size (small or large) had significantly less bark than dead trees and that large dead trees had significantly more cracks compared with live trees (small and large) and small dead trees. In rehabilitated areas, trees had similar characteristics to trees of comparable size in the jarrah forest. It was concluded that the absence of large dead trees (the biggest source of cracks) in rehabilitated mine-pits could be preventing the return of the marbled gecko and wall skink to these areas. A trap was designed to specifically target the two study species, so it could be determined what size and senescence of jarrah tree in un-mined forest was most preferred by the wall skink and marbled gecko. Three experiments were conducted. The first experiment was an olfactory experiment wherein wall skinks significantly tongue-flicked towards crickets more than the other four baits tested (fruit flies, mealworms, cockroaches and peanut butter). No significant response was given for any of the five baits by the marbled gecko. As a result crickets were used as the bait. The second experiment examined the attractiveness of different visual and acoustic cues (live crickets, live mealworms, live fruit flies, live cockroaches, peanut butter, a flashing LED light and darkness/cover) using a Y-maze. The wall skink had a significant aversion to darkness/cover. The marbled gecko did not show a significant aversion or attraction to any of the seven stimuli tested. As a result the trap was made from aluminium fly-wire which allowed light through. The final experiment looked at what material was best to use for the drift-fence. It was found that damp-proof flashing with cooking oil applied was the best material to use as it was difficult to climb for both the marbled gecko and wall skink. Consequently flashing was used as the drift-fence material; however, oil was not applied as it became sticky when left in the sun. Because of low capture rates of the marbled gecko and wall skink, microhabitat requirements can only be inferred from apparent general trends. Arboreal lizards apparently preferred dead jarrah trees over live jarrah trees, as all reptile captures were on dead trees. However, no significant preference was shown for the size (small or large) of jarrah tree. Trees on which reptiles were caught were associated with high numbers of cracks (which can be used as shelter sites) low canopy cover (which increases insolation through the canopy for basking), and a greater number and volume of logs in close proximity (which can be used as foraging and basking sites). These findings suggest that these habitat components may be determining factors in the presence/absence of arboreal reptiles (including the wall skink and marbled gecko) in the jarrah forest. The present study also examined whether marbled geckos and wall skinks will re-colonised rehabilitated mine-pits where habitat has been provided by thinning using two different techniques, notching with herbicide injections (to produce dead standing stags) and cutting trees with a chainsaw (to produce small logs). The provision of habitat in the form of dead stags and logs apparently did not facilitate the re-colonisation of the two target species, since no reptiles were observed in any of the rehabilitated mine-pits. Reasons for this may be the lack of both dead stags and logs in the one rehabilitated site as arboreal reptiles were found using a combination of logs as well as dead stags in un-mined forest. Also the absence of larger dead stags and logs could also be limiting factors, since large, dead stags were the biggest source of cracks in the native jarrah forest and large logs found to be used by the wall skink for foraging sites. From the findings of this study it is recommended that large logs as well as large dead stags are transported into rehabilitated mine-pits. In addition, notching of trees is recommended to occur in stages over a period of time to produce dead stags of many sizes. These recommendations are likely to encourage the re-colonisation of the wall skink and marbled gecko. However, more research is required on the longevity of dead stags and the importance of logs to the two study species.

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Anderson, Nathaniel S. "Ecophysiological mechanisms underpinning resilience to climate change in the Northern Jarrah Forest (Western Australia)." Thesis, Anderson, Nathaniel S. (2020) Ecophysiological mechanisms underpinning resilience to climate change in the Northern Jarrah Forest (Western Australia). Honours thesis, Murdoch University, 2020. https://researchrepository.murdoch.edu.au/id/eprint/59134/.

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Southwestern Australia has experienced a consistent warming and drying trend since the 1970s. Alongside changes in mean climate, extreme events such as droughts and heat waves have also increased in frequency and are linked to forest canopy collapse and larger, more severe bushfires. The increasing frequency of drought, heat waves, and wildfires associated with climate change highlight the importance of understanding forest recovery after disturbances. A key area of uncertainty is how climate disturbances such as drought and heatwaves interact with other events such as wildfire. Plant leaves link atmospheric processes to forest water availability, contribute to fine fuel dynamics, and have impacts on bushfire severity through their live foliar moisture content. These make leaves an ideal medium for studying forest recovery from climate change related disturbances. This study investigated the ecophysiological functioning of Eucalyptus marginata in stands of forest recovering from a drought/heatwave in 2010/2011 and the Waroona-Yarloop wildfire in 2016. Pre-dawn leaf water potential, stomatal conductance, chlorophyll fluorescence, change in leaf temperature, specific leaf area, live foliar moisture content, and Huber values provided the basis for comparison between plots affected by the drought/heatwave event, the wildfire, and a combination of these disturbances. Measurements were taken in the summer and winter to provide low and high values (respectively) for ecophysiological functioning. The high probability drought, high severity fire plot had the lowest pre-dawn leaf water potentials, and reduced stomatal conductance. A number of trees adjacent to this plot died or had canopy contractions between the summer and winter measurements. The combination of observed tree death and low pre-dawn leaf water potentials suggests that for E. marginata, the interplay of drought and fire is pushing vulnerable portions of the forest beyond their threshold of survival.

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Pettit, Neil. "Effects of livestock grazing on the structures and composition of jarrah (Eucalyptus marginata) woodland remnants." Thesis, Pettit, Neil (1995) Effects of livestock grazing on the structures and composition of jarrah (Eucalyptus marginata) woodland remnants. Masters by Research thesis, Murdoch University, 1995. https://researchrepository.murdoch.edu.au/id/eprint/52501/.

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Grazing by livestock has led to passive clearing of the majority of remaining areas of native vegetation on farmland (remnants) in the Collie river catchment in the south-west of Western Australia. Livestock grazing in these areas removes most of the understorey and prevents recruitment. This thesis documents the impact of livestock grazing on the vegetation dynamics of these remnants through changes to floristics and structure and effects on the soil. It also looks at the possibility of rehabilitation of degraded areas by assessing seed reserves in the soil seedbank and the regeneration of species with the exclusion of grazing. A review of the literature provided a background to this study and looks at the broader issues of the significance of remnants of native vegetation as well as the ecology of disturbance in terms of vegetation response and resilience and deals with the problems of management. Species diversity and richness have decreased with increased grazing intensity and these were negatively correlated with proportion of exotic species. Site ordination of a large sample of remnants placed sites in two major groups based on grazing intensity, with position of sites influenced by proportion of exotic species, proportion of perennial herbs and shrubs and species diversity and richness. Cover and abundance of native perennial species decreased, but increased for exotic annual species with a gradient of response between heavily grazed, lightly grazed and ungrazed sites. Other life form groups such as native annuals, geophytes and native grasses were not significantly affected by grazing. Perennial species that are able to resprout from an underground storage organ as well as germinate readily from seed appear the most resilient to grazing disturbance. Effects of grazing disturbance on the soil included increased surface soil compaction and water repellency as well as significant increases in concentrations of soil nutrients, particularly N and P. Age structure of overstorey species indicated that there has been a lack of recruitment at the heavily grazed sites for some time. Germination of overstorey species took place each year of the study but mortality of seedlings was high, with no seedlings surviving after one summer at the heavily grazed sites. Experiments on the soil seedbank showed a dominance of seed from exotic annual species and a lack of seed from native perennial species within the heavily grazed sites, indicating that natural regeneration is unlikely from this source. Heat treatment of soil samples showed a decrease in germination of exotic species and an increase in the germination of native species. After l to 3 years there was a significant increase in number and cover of native perennial species in exclosure plots, mainly from resprouting. The greatest increase in cover in exclosures was seen for native perennial grasses, while abundance of exotic annuals did not increase significantly compared to adjacent open plots. Time series ordination showed the movement of exclosure plots towards the ungrazed plots after three years, indicating the increase in floristic similarity between the exclosures and the ungrazed plots. This study has shown that grazing has resulted in a shift from a community dominated by native perennial species to one dominated by exotic annual species. High grazing intensity and short grazing history, climatic variability and effects on the soil are the major factors affecting the observed ·responses of the vegetation to grazing. Natural regeneration in degraded remnants is possible if livestock are excluded. Rehabilitation of some sites is also required and a procedure is suggested.

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Rasmussen, Travis. "Determining the effects of drought and fire on tree regeneration in the Northern Jarrah Forest." Thesis, Rasmussen, Travis (2020) Determining the effects of drought and fire on tree regeneration in the Northern Jarrah Forest. Honours thesis, Murdoch University, 2020. https://researchrepository.murdoch.edu.au/id/eprint/59136/.

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Forest ecosystems in fire-prone regions globally have a high level of resilience. However, as the climate changes, the level of frequency and severity of disturbances is expected to increase. This may influence the likelihood of multiple disturbance events occurring and impeding the ability of a forest to regenerate. Tree regeneration has been previously examined, although evidence-based data assessing tree regeneration following multiple disturbances are rare, limiting the capability to predict forests recovery and persistence once a disturbance occurs. This study expanded upon two earlier studies to quantify the regeneration of overstorey and midstorey species ten years after drought-induced canopy die-off and three years following a mixed-severity wildfire that burnt under extreme fire weather. The effects of prescribed burning were also examined by including prescribed burning activity of the same time since fire as the wildfire event. This study investigated three main questions. (1) How is tree regeneration affected by drought and fire? (2) How do growth stages of tree regeneration vary by drought and fire severity? Lastly, (3) How does tree regeneration respond to fire over time? The study found that firstly, under a drought and fire interaction, regeneration density significantly increased, secondly, lignotuberous seedlings and seedling coppice were the most dominant growth stage identified with significantly higher densities following moderate severity fire. Thirdly, moderate severity fire displayed higher densities over the three years since wildfire, however, prescribed burning and high severity fire showed less regeneration abundance by comparison. This study highlights the need for future research in prescribed burning techniques and an increase in forest management practices due to the increased risk of higher fire severities. Furthermore, it illustrates the necessity of understanding the long-term trajectory of tree regeneration following multiple disturbance events.

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Nielsen, Zigourney. "Within-fire patchiness associated with prescribed burning in the northern Jarrah forests of Western Australia." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2018. https://ro.ecu.edu.au/theses/2070.

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There is growing understanding of the importance of landscape mosaics and heterogeneity for biodiversity outcomes in Western Australia. However, there is limited information on the patchiness (spatial configuration of unburnt and burnt patches which occur at a range of spatial scales) within the perimeter of a single prescribed burn. Of particular concern is the idea that prescribed burning operations, carried out under very restricted weather and environmental conditions, can lead to structural and floristic homogenization of the area within a burn perimeter. This may be evident as reduced post-fire vegetation patchiness. Western Australian Jarrah (Eucalyptus marginata) forests are managed to reduce fuel loads to protect life and property. Additionally, specific biodiversity and fuel reduction programs are completed by means of low intensity controlled burns carried out by the Parks and Wildlife Service, part of the Department of Biodiversity, Conservation and Attractions. The northern Jarrah forest is thus an ideal study site to test whether prescribed burning homogenizes a within-burn area. The objective of this study was to determine the post-fire patchiness of vegetation following prescribed burning to assess the potential for homogenisation of the within-burn area of Jarrah forests. To achieve this, a set of post-burn surveys were created to determine the patchiness of the burnt areas within 18 prescribed burns. The quantitative post-burn assessment designed in this study was evaluated to determine if it is suitable to be used as a possible future management option. A survey was undertaken to obtain data on 29 environmental variables which capture the variability across an individual prescribed burn area to determine the within-burn fire characteristics. A Pearson correlation matrix table was constructed to determine the significant correlations between variables as well as the strength of the relationships (coefficient of determination, r2). The patchiness between seasons autumn and spring was compared. Generalised Linear Modelling (GLM), and the application of Akaike were used to identify which variables were essential and most significant in predicting patchiness, to produce a list of candidate models. The AICc indicated which models were the most parsimonious or plausible candidate models (AICc < 2). Structured Equation Modelling (SEM) was completed to determine which variables in the ‘most parsimonious’ model were the greatest contributors to the model. It was found that the number of vegetation patches decreased with an increase in fire intensity and percentage of area burnt. Autumn and spring burns were not significantly different in terms of overall patchiness and the majority of patches were found to be small, between 1 – 10 m in length. Surface Moisture Content (SMC) was the only pre-fire condition variable that negatively influenced prescribed burn fire intensity and subsequently patchiness, while time since last burn was found to increase the number of vegetation patches and SMC. The post-fire survey data obtained in this study on the 18 post fire sites was also compared to the post-burn assessments completed by Parks and Wildlife Service on the same sites. GLM and AICc showed that the variables Fire Danger Index, ash cover (%), area burnt (%), month of fire and the number of vegetation patches, are the most parsimonious and ‘best’ fit at predictors of patchiness within a prescribed burn area. While SEM showed that area burnt (%) was the most important predictor of patchiness. Within-burn patchiness appeared to be low in the study sites. Results from the prescribed burns in the northern jarrah forests showed that in most prescribed fires, 90 to 100% of the vegetation area was burnt with a limited number of unburned patches (up to 12 km-1) remaining. Although successful for fuel reduction burning, such large scale vegetation loss has been found to lead to structural homogenisation within a burn area, which in turn can result in long-term impacts on biodiversity. This study thus showed that prescribed burns in the northern Jarrah forest can homogenise the within-burn area and the implications of these findings are discussed in the broader context of landscape patchiness. This study also shows that a quantitative post-fire patchiness survey similar to that designed here should be developed as a future management option.

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Watson, Alexander W. "A comparison of logging and fire disturbance on biophysical attributes of the Northern jarrah forest." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2006. https://ro.ecu.edu.au/theses/103.

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Ecologically sustainable forest management (ESFM) serves dual purposes: 1) to ensure the conservation of biodiversity, and 2) in production forest (forest managed for the production of timber and woodchips), to maintain an economically viable timber industry in perpetuity. A central axiom of ESFM is that any manipulation of a forest ecosystem should emulate the `natural' disturbance patterns of the forest. This is based on the assumption that forest communities have evolved with endogenous disturbance regimes and will be better able to cope if exogenous disturbance (e.g., logging) remains within natural levels and spatial and temporal bounds of intensity. The objective of this thesis was to assess whether logging within one of Australia's temperate forest ecosystems, the jarrah forest, falls within the range of its natural disturbance regimes and if not, whether logging reduces biodiversity within this ecosystem. As fire is the predominant natural disturbance in most Australian temperate forest, this objective was achieved by examining (i) whether there were initial differences between the impact of fire in unlogged forest compared with the impact of logging and fire in production forest and (ii) whether the biodiversity impacted by logging disturbance recovered within a period of time equivalent to that required for recovery from disturbance caused by fire.

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Hayward, Matt School of Biological Earth &amp Environmental Science UNSW. "The ecology of the quokka (Setonix brachyurus) (Macropodidae: Marsupialia) in the Northern Jarrah Forest of Australia." Awarded by:University of New South Wales. School of Biological, Earth and Environmental Science, 2002. http://handle.unsw.edu.au/1959.4/18768.

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The quokka (Setonix brachyurus Quoy & Gaimard 1830) is a medium-sized, macropodid marsupial that is endemic to the mesic, south-western corner of Australia. While being a tourist icon on Rottnest Island, the species is threatened with extinction. It has been intensively studied on Rottnest Island in the 1960s and 1970s, however very little is known of its ecology on the mainland. Additionally the insular and mainland environments are extremely different suggesting that ecological differences between the two populations are likely. Consequently, this study sought to determine the basic autecology of the quokka and identify what factors have attributed to its threatened conservation status. The northern jarrah forest of Western Australia was selected as the study region due to it being at the northern limit of extant quokka distribution and because it was thought that the factors threatening the quokka would be exacerbated there. Fossil deposits suggest that the quokka originally occupied an area of approximately 49,000 km2 in the south-western corner of Australia. Historical literature show that they were widespread and abundant when Europeans colonised the region in 1829 but a noticeable and dramatic decline occurred a century later. The arrival of the red fox to the region coincided almost exactly with this decline and so it was probably ultimately responsible. Continued predation by both it and the feral cat are likely to have continued the decline, along with habitat destruction and modification through altered fire regimes. Specific surveys and literature searches show that since the 1950s, the area occupied by the quokka has declined by 45% and since 1990 by 29%. Based on the criteria of the IUCN (Hilton-Taylor 2000), the conservation status of the quokka should remain as vulnerable. An endangered status may be more applicable if the quokkas restriction to patches through its existence as a metapopulation is considered. Trapping of eight sites supporting quokka populations in the mid-1990s revealed three sites now locally extinct despite the ongoing, six year old, fox control programme. Another three are at serious risk of extinction. Extant population sizes ranged from one to 36 and population density ranged from 0.07 to 4.3 individuals per hectare. This is considered to be below the carrying capacity of each site. The overall quokka population size in the northern jarrah forest may be as low as 150 adult individuals, of which half are likely to be female. Even the largest extant populations are highly susceptible to stochastic extinction events. This small size was surprising considering the six year old, introduced predator control programme. Historically, the restriction to discrete habitat patches, the occasional inter-patch movement, the lack of correlation between the dynamics of each population and reports of frequent localised extinctions and colonisations suggest that the quokka population once existed as part of a classic metapopulation. The massive decline of the quokka in the 1930s pushed the metapopulation structure into a non-equilibrium state such that today, the extant populations are the terminal remnants of the original classic metapopulation. Wild mainland quokkas breed throughout the year. A significant reduction in the number of births occurs over summer and this coincides with a decline in female body weight. Despite this, the mainland quokka is relatively fecund and is able to wean two offspring per year. The level of recruitment from pouch young to independence was low and this may explain the apparent lack of population increase following the initiation of fox control. A total of 56 trapped quokkas were fitted with a radio collar. Mean home range size for quokkas was 6.39 ha with a core range of 1.21 ha and this was negatively related to population density. Male home ranges were larger than females but not significantly when the sexual size dimorphism was considered. Nocturnal ranges were larger than diurnal ranges reflecting nocturnal departures from the swamp refugia. Home range sizes varied seasonally, probably due to changes in the distance required to move to obtain sufficient nutrients and water over the dry summer compared to the wet winter and spring. Telemetry confirmed trapping results that showed no movement between swamps or populations. Home range centres shifted to the periphery of the swamp following the winter inundation and this may increase the species susceptibility to predation. The lack of dispersal is probably caused by quokka populations existing below carrying capacity and following selection for philopatry under the threat of predation for dispersing individuals. Without dispersal to recolonise or rescue unpopulated patches, the collapse of the original quokka metapopulation appears to have occurred. On a macrohabitat scale, the quokka in the northern jarrah forest is restricted to Agonis swamp shrubland habitats that form in the open, upper reaches of creek systems on the western side of the forest. This restriction was probably initially due to the high water requirements of the quokka but is likely to have been exacerbated by increased predation pressure since the arrival of the fox. On a microhabitat scale, the quokka is a habitat specialist, preferring early seral stage swamp habitats, probably for foraging, as part of a mosaic of old age swamp that provides refuge. Despite the six year old, introduced predator control programme, foxes and cats are still the major cause of mortality to quokkas. Road kills was the other identifiable cause. Individuals alive at the start of the study had an 81% chance of staying alive until the end. The likelihood of dying was minimised by grouping together with conspecifics, maximising home range size and maximising the time spent within the swampy refuge. Current rates of adult and juvenile survivorship should allow population recovery and so it seems pouch young mortality, reflected by low recruitment, has inhibited the anticipated population increase following predator control. The confounding effect of inadequate unbaited controls meant that little statistical evidence was available on the impact of introduced predators on the quokka, however the models provided support for earlier hypotheses of these. The presence of a quokka population at a site was related to the amount of poison baits delivered ??? reflecting predation pressure, the average age of the swamp and a mosaic of early and late seral stages within the swamp habitat. Recently burnt habitat is thought to provide food for quokkas and long unburnt habitat provides refuge from predation.

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Edwards, John. "Public health implications of metal ash concentrations from prescribed burns: A study of open jarrah forests." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2018. https://ro.ecu.edu.au/theses/2052.

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Ash is not a homogenous product. It is the solid residue of combustion and contains a complex mixture of chemical products. The fire that produces ash is non-discriminatory in that it will burn anything that is combustible. The ash residue resulting from fires varies and is dependent on its source, and burn characteristics such as the temperature of the fire. Ash comprises particles of carbon, soot and trace elements. Ash presents public health risk to people and communities, through direct and indirect ingestion, inhalation and absorption. The health effects of ash exposure are not limited to symptoms affecting the eyes, throat and lungs. They can contribute to chronic disease and increase the risk of cancer. The purpose of this study was to evaluate the public health implications of controlled burns in the Darling Escarpment, adjacent to Perth’s metropolitan area in Western Australia. Concentrations of metals in unburnt vegetative litter and ash (post burn), stratified by size fraction, were determined to assess the potential mobilisation of metals caused by prescribed burns and the potential public health implications associated with burns. These data can also be used in predictive modelling to ascertain the amount of metals likely to be released per hectare when authorities plan future burns in the area. Ash samples were collected immediately following the fire to capture fine material before it was blown away. The ash samples were separated into size fractions to investigate whether there are differences within each sub sample. Australia’s National Environmental Protection Measures were used to establish whether the metal concentrations were above designated thresholds for health and environmental investigation, these being the recognised levels above which metals are deemed to pose a risk to public (or environmental) health. Vegetation and ash samples were collected from three sites immediately after the prescribed burn. Samples were analysed for thirteen (13) metals with nine (9) showing statistically significant increases in concentrations in vegetation as compared to ash. The percentages of metals are higher in ash than in vegetative ground litter. The metals identified are Manganese - Vegetation (158.3 ± 89.3 mg/kg), Ash (442.2 ± 462.6 mg/kg); Barium - Vegetation (19.4 ± 25.3 mg/kg); Ash (41.8 ± 62.7 mg/kg); Zinc - Vegetation (15.3 ± 9.7 mg/kg), Ash (25.6 ± 29.7 mg/kg); Vanadium - Vegetation (31.0 mg/kg ± 76.3 mg/kg), Ash (32.2 mg/kg ± 51.0 mg/kg); Copper - Vegetation (4.2 ± 1.5 mg/kg), Ash (10.9 ± 9.8 mg/kg); Chromium (Total) - Vegetation (8.3 ± 15.6 mg/kg), Ash (9.6 ± 12.4 mg/kg); Lead - Vegetation (6.1 ± 8.3 mg/kg), Ash (12.2 ± 8.5 mg/kg); Nickel - Vegetation (2.2 ± 2.2 mg/kg), Ash (4.7 ± 4.4mg/kg) and Cadmium - Vegetation (0.6 ± 0.9 mg/kg), Ash (0.6 ± 0.9 mg/kg). The ash samples were sieved through three aperture’s (2-4 mm, 1-2 mm, <1 mm) to stratify the samples by size fraction and concentrations in all but three of the metals increased as the ash size decreased. It was demonstrated that the level of metal present within the ash samples did not exceed health investigation levels and, with the exception of Manganese, and did not exceed environmental investigations levels. Metals were unlikely to pose a risk if left in-situ. However, modelling estimated the volume of metal released and it was determined that metals can pose a subsequent risk if mobilised by wind or water. The likelihood of such mobilisation is high and this finding therefore has public health implications for surrounding communities that are subjected to increases in their exposure to metals, associated with bushfires. The findings from this study contribute to the management of prescribed burns by providing a better understanding of the composition of ash and the effects of potential distribution via aerial deposition or runoff. Data from this study can be used to do predictive modelling of heavy metal mobilisation that may result from burns of similar vegetation environments. This becomes particularly significant where burns are conducted in water catchment areas.

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Webala, Paul. "Bat community structure and habitat use across logging regimes in jarrah eucalypt forests of south-western Australia." Thesis, Webala, Paul (2010) Bat community structure and habitat use across logging regimes in jarrah eucalypt forests of south-western Australia. PhD thesis, Murdoch University, 2010. https://researchrepository.murdoch.edu.au/id/eprint/4867/.

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In many parts of the world, the increasing demand for timber and other forest products has led to loss, fragmentation, degradation or modification of natural forest habitats. The consequences of such habitat changes have been well studied for some animal groups, however not much is known of their effects on bats. In Australia, logging of native forests is a major threat to the continent‘s biodiversity and while logging practices have undergone great changes in the past three decades to selective logging (including ecologically sustainable forest management), which is more sympathetic to wildlife, there is still concern about the effects of logging on the habitat of many forest-dwelling animals. The goal of this thesis was to investigate the effects of logging on the bat species assemblages at both community and individual species levels in terms of their foraging and roosting ecology in jarrah forests of south-western Australia. This information is necessary to strengthen the scientific basis for ecologically sustainable forest management in production forests. The outcome of this research may help in the formulation of policy and management decisions to ensure the long-term maintenance and survival of viable populations of forest-dwelling bats in these altered environments. Bats were selected because they comprise more than 25% of Australia‘s mammal species and constitute a major component of Australia‘s biodiversity. In addition, bats play key roles in forest dynamics and may act as indicators of disturbance. In the jarrah forests, bats are a significant proportion of the mammal fauna (9 of around 30 native extant species). As a basis of understanding how bats use modified habitats, nine species of bats were investigated by assessing their foraging and commuting habits (measured as bat activity) in different forest types (logged, young regrowth and old regrowth forest). To assess patterns of habitat use across a gradient of managed forest conditions, and to help predict impacts of logging on bats, four replicates were selected from each of three distinct post-harvest management treatments, recently logged forest or gaps (<6 years since logging), young regrowth forest (12–30 years since logging) and old regrowth forest (> 30 years old). Sites were monitored for bat activity on two nights, with Anabat detectors placed on track and off-track positions. The relationships between bat species assemblages in terms of their relative use and foraging activity and various forest structural variables, and the relationship between bats and the insect biomass were examined in order to identify the effects on the bat fauna of historical logging practices. Overall, 12 sites were sampled (four sites for each forest type) with bat activity and vegetation structure conducted on-track and off-track at each site and insect abundance sampled only at off-track sites. Secondly, because roosts are an important resource for bats, and may be a limiting factor in modified landscapes, we investigated the roosting requirements of two sympatric species of jarrah forest-dwelling vespertilionid bats, the Southern forest bat Vespadelus regulus and Gould‘s long-eared bat Nyctophilus gouldi. Their sensitivity to the loss of roost sites from logging and the effectiveness of current management practices at conserving appropriate roost sites were examined. As part of the research, tree (age, size, type, condition, presence of hollows, loose bark) and landscape characteristics (elevation, logging history, distance to water holes and creeklines, etc) of roosting sites were compared with random trees and their surrounding forest structure at local roost tree and broader landscape scales to determine whether bats selected roost trees and sites with particular characteristics. The fieldwork was carried out during 2007 – 2009 and information was gathered through capture, radiotelemetry and passive monitoring using echolocation call detectors. Specifically, harp traps and radiotelemetry were used for roost-selection studies while Anabat bat detectors were used to assess bat activity (commuting, foraging) among different logging histories and in response to forest structural attributes and insect activity. Light traps were used to assess insect availability in relation to bat activity and forest structure. The activity of different bat species related in different ways to the structural vegetation parameters, generally reflecting bat echolocation ability and manoeuvrability. Bats tended to use tracks more than off-track locations, thereby avoiding clutter at off-track locations. At the same time, tracks recorded similar activity across logging histories. However, off-track activity in old regrowth was significantly greater than either young regrowth or recently logged forest. Two taxa, Vespadelus regulus and Nyctophilus spp. were more active in old regrowth than other logging histories. Similarly, V. regulus, Nyctophilus spp., Chalinolobus gouldii, C. morio and Falsistrellus mackenziei activity was significantly greater on-track than off-track, but this activity was similar on-track across forest types, suggesting bats‘ use of forest tracks was unaffected by logging. As an indication of the association of low bat activity off-track with clutter, negative relationships of under-storey clutter were the most consistent predictors of bat habitat use. Conversely, reduced clutter and abundant roost resources seemed the most likely explanations for greater activity at old regrowth sites. There were both inter-specific similarities and differences in the selection and location of roost trees and roost sites between V. regulus and N. gouldi. Both species were highly selective, preferring old large trees (> 80 cm diameter at breast height over bark – DBHOB) at intermediate or advanced stages of decay, crown senescence and deterioration with a lower percent bark cover compared to random trees. Both species also selected hollows for roosting, with V. regulus roosting exclusively in hollows but a few N. gouldi also used roosts under decorticating bark, cracks and under balga (Xanthorrhoea preissii) skirts. V. regulus preferred tall trees in the canopy with roost entrances high above the ground with little surrounding vegetation while N. gouldi preferred roosting closer to the ground and in dense clutter. In general, little evidence was found of bats roosting in either shelterwood creation or gap release silvicultural treatments, although a few N. gouldi bats roosted in retained habitat, or remnant, trees in these silvicultural treatments. Only riparian buffers and structurally mature forests appeared to provide multiple alternate roosts, containing a higher density of trees with hollows required by bats for roosting. In contrast, gap release and shelterwood creation sites contained substantially lower densities of hollow bearing trees. Pockets of mature forest that were previously only lightly and selectively logged before the introduction of Ecologically Sustainable Forest Management (ESFM) were important roosting sites for bats. However, although some N. gouldi bats selected roosts in retained or remnant trees in gap release and shelterwood creation silvicultural treatments, it remains unclear if bats can successfully breed in such regrowth forests in the absence of older forest stands and this should be a priority for future studies. This study demonstrated that unharvested buffer strips surrounding ephemeral streams, and more open mature forests, with reduced midstoreys, were important roosting habitats for bats because they provided a large pool of older and mature trees in a variety of decay classes as roost sites. With short logging rotations in the jarrah forests and with only approximately 39 % total forest area currently reserved from logging in the study area, the roosting requirements of bats may be affected negatively as the abundance of old trees with hollows, exfoliating bark and other forms of senescence may be reduced. Thus, although this study demonstrated the importance of mature forest and buffers as mitigating measures on bat roost sites, it was unclear whether the area of retained habitat is adequate for for roosting bats given the dynamics of logging regimes in the jarrah forests, and this should be a priority to address in future research. As the only mammals capable of true flight, bats may persist in selectively logged forests. However, as this study showed, bats are specialised in their foraging and roosting requirements. Therefore, the maintenance of forest tracks and the protection, and sustained recruitment, of hollow-bearing trees are essential for the conservation of these animals in such modified landscapes. Current management practices in the jarrah forests have created a mosaic of successional stages within logged landscapes that may satisfy the foraging requirements of many bat species. This is especially true because tracks and unlogged buffers and structurally mature forest with reduced clutter provided access to post-disturbance forests such as regrowth areas. The study also demonstrated that habitat retention, as provided by adjacent streamside buffers and mature forest in the jarrah forests were important roost sites for bats, and could mitigate against logging impacts in the long term. However, retained habitat trees in logged coupes were avoided by roosting bats and further studies are required to demonstrate if these can be used effectively by viable bat populations, especially in the absence mature unlogged forest and unlogged riparian buffers nearby. In addition, further research is required to shed light on bat overwintering and maternity roost sites that are important for the survival of bat populations. In addition, a long-term study to clarify temporal/seasonal and intra-specific variation in bat distribution and roost site selection needs to be undertaken in the jarrah forests of south-western Australia to better determine if current ESFM practices are effective at maintaining bat populations in logged forests.

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Monaco, Sophie. "Seed dispersal, herbivory and recruitment failure of Persoonia elliptica (Proteaceae) in Western Australian Jarrah (Eucalyptus marginata) forest." Thesis, Monaco, Sophie (2012) Seed dispersal, herbivory and recruitment failure of Persoonia elliptica (Proteaceae) in Western Australian Jarrah (Eucalyptus marginata) forest. Honours thesis, Murdoch University, 2012. https://researchrepository.murdoch.edu.au/id/eprint/15075/.

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Persoonia elliptica is a resprouting understorey tree species of the jarrah (Eucalyptus marginata) forests of South-Western Australia. All known populations are lacking in seedlings and saplings, resulting in population structures made up solely of mature trees and exhibiting clear recruitment failure. Little research has been done on this species other than a single study by Abbott and Van Heurck (1988) which described population structures and speculated that increased kangaroo herbivory might be the cause of recruitment failure. This study addresses the issue of recruitment failure, in particular with regards to seed production, viability and dispersal, and herbivory. This work describes the ecology of the species including fruit production, seed viability and population structure. The relationship between P. elliptica and the fauna of the region is examined with regard to seed dispersal vectors and dispersal distances, while the role macropods play in seedling and new growth herbivory and the link with recruitment failure is also examined. Two study sites were investigated over a period of eight months in the northern jarrah forest region, at Avon Valley National Park and in state forest near Sawyers Valley. Species ecology was examined using fruit counts, tree size measurements and soil seed bank estimation, while seed dispersal and herbivory were examined using seed removal ‘cafeteria’ experiments and infrared motion sensing cameras to detect and record faunal activity. Fruit production is low in P. elliptica with only 9% of flowers becoming mature fruits. Seed viability is high in new season seeds, but seeds collected from the soil seed bank (assumed aged one year or older) were not viable. Five fauna species act as dispersal vectors of P. elliptica seed; Macropus fuliginosus, Macropus Irma, Strepera versicolour, Mus musculus and Oryctolagus cuniculus. Of these the currawong (S. versicolour) has not previously been observed interacting with P. elliptica seeds. Macropods exhibited a strong browsing preference for P. elliptica when presented with fresh foliage, and are also therefore, likely to consume seedlings. The wallaby, M. Irma, browsed foliage to a height of 0.5 metres while the kangaroo, M. fuliginosus, browsed foliage up to one metre. This level of browsing pressure is a potential cause of recruitment failure. The key findings of the study highlight that recruitment failure within populations of P. elliptica is likely to be caused by a number of factors potentially relating to the species ecology and relationships with fauna, particularly herbivores. This raises questions on the potential for this species to persist into the future within the jarrah forest and provides vital information concerning possible management approaches to encourage recruitment.

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Seaton, Stephen. "Behaviour of woodborers (Coleoptera: Cerambycidae) and sapwood moisture in a drought affected Northern Jarrah (Eucalyptus marginata) Forest." Thesis, Seaton, Stephen ORCID: 0000-0002-1076-6005 (2018) Behaviour of woodborers (Coleoptera: Cerambycidae) and sapwood moisture in a drought affected Northern Jarrah (Eucalyptus marginata) Forest. PhD thesis, Murdoch University, 2018. https://researchrepository.murdoch.edu.au/id/eprint/43158/.

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A severe drought event during 2011 in the Northern Jarrah (Eucalyptus marginata Don Ex Smith) Forest of southwestern Australia, provided ideal conditions for an outbreak of the eucalyptus longhorned borer Phoracantha semipunctata Fabricius (Coleoptera: Cerambycidae). Located in a Mediterranean climatic zone, the jarrah forest region is expected to experience increased frequency of droughts causing tree mortality, yet little is known of endemic borer activity in response to tree drying. A detailed study was conducted within the jarrah forest following the drought, with the overall aim to provide an understanding of the role of sapwood moisture in controlling the infestation and development of longhorned borers. This was achieved using a field-based approach within a natural habitat and addresses the following key objectives: (a) assess the influence of seasons on infestation by key borer species, (b) determine the role of parasitoid wasps in controlling borer infestations, and (c) evaluate the influence of the two main Eucalyptus species, jarrah and marri (Corymbia calophylla L.A.S Johnson) on borer behaviour. Deterioration in crown health during the drought was associated with increased emergence of P. semipunctata and this was higher in larger lower tree sections where differences in emergence occurred between tree species and favoured marri with thicker bark compared to smaller higher tree sections with thinner bark. Poor survival of neonate larvae in both species was associated with overlapping galleries at high larval incidence, indicating intense competition for sapwood resources among developing larvae, while pupal survival remained high. This is the first study to show Coptocercus rubripes Boisduval to be an important borer along with P. semipunctata in the jarrah forest. Coptocercus rubripes mainly attacked in spring, prefers jarrah, has singular galleries per oviposition site, and grew slowly over spring to autumn, emerging in autumn-winter. Phoracantha semipunctata mainly attacked in the dry warm summer months, preferred marri, has many galleries per oviposition site, and grew rapidly over summer-autumn, emerging in summer the following year. Once sapwood moisture content in water stressed trees decreased by 19 % below turgid levels (independent of tree species), coinciding with a change in colour of canopy leaves of trees from green to yellow, conditions were suitable for borer larvae to establish. As sapwood dried, the larger P. semipunctata developed quicker and galleries were more extensive than C. rubripes. Larvae of various ages contributed to total sapwood consumption and reached a maximum at higher moisture contents in marri than jarrah. The native parasitic wasps Syngaster lepidus Brulle and Callibracon limbatus Brulle attacked maturing borer larvae of C. rubripes and P. semipunctata in stressed jarrah and marri hosts. Parasitism averaged 67 % and was inversely related to larval density. In the absence of parasitoids, borer survival in caged logs was greatly improved, although 30 % mortality still occurred and was attributed to increased competition among developing larvae. This research shows falling sapwood moisture has a key role for borer infestation and development in response to drought stress within forests and can be influenced by borer and tree species, parasitoids, and season. This knowledge will enable better management of cerambycids in forests subject to drought.

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Hyams, Michelle. "Can design generate information to aid in technological innovation? an investigation using industry based case studies /." Swinburne Research Bank, 2008. http://hdl.handle.net/1959.3/42017.

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Thesis (MDes) - National School of Design, Swinburne University of Technology, 2008.
[Thesis submitted for degree of] Master of Design, to the [Faculty of Design], Swinburne University of Technology, 2008. Typescript. Bibliography: p. 159-165.

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31

Pilbeam, Ros. "Effects of phosphite on disease development and histological responses in Eucalyptus marginata infected with Phytophthora cinnamomi." Thesis, Pilbeam, Ros (2003) Effects of phosphite on disease development and histological responses in Eucalyptus marginata infected with Phytophthora cinnamomi. PhD thesis, Murdoch University, 2003. https://researchrepository.murdoch.edu.au/id/eprint/260/.

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Phosphite is currently used for the management of Phytophthora cinnamomi in native plant communities. A greater understanding of how phosphite affects the host-pathogen interaction is required in order to determine the most effective treatment. This thesis aimed to investigate the effects of applied phosphite concentration on phytotoxicity, in planta concentration of phosphite, disease development and anatomical responses of Eucalyptus marginata. Spraying the foliage to run-off with 7.5 and 10 g phosphite/L led to the development of severe leaf necrosis within 7 days, with greater than 60% of the leaf area damaged. Moderate phytotoxicity was observed after treatment with 5 g phosphite/L. In planta concentration of phosphite in stems, lignotubers and roots did not differ significantly between applied concentrations of phosphite. Stem tissue contained the largest concentration of phosphite at one week after spraying, with approximately 210 and 420 g phosphite/g dry weight detected after treatment with 5 and 10 g phosphite/L, respectively. In a subsequent field trial, the applied concentration of phosphite was found to affect the duration of effectiveness of phosphite in protecting E. marginata seedlings from stem colonisation by P. cinnamomi. Plants were wound-inoculated with P. cinnamomi at 6-monthly intervals after spraying with phosphite. The 2.5 and 5 g phosphite/L treatments were effective against colonisation by P. cinnamomi when inoculated 0 and 6 months after spraying, but only the 5 g phosphite/L treatment inhibited P. cinnamomi within 12 months of spraying. Phosphite had no effect on colonisation by P. cinnamomi when plants were inoculated at 17 months after spraying. The in planta concentration of phosphite detected in the leaves, stems and roots of plants treated with 5 g phosphite/L did not differ significantly between the time of harvest or tissue type at 0.2 and 6 months after spraying. P. cinnamomi remained viable in plants treated with phosphite.Treatment with 2.5 and 5 g phosphite/L when P. cinnamomi was well established in the stems was ineffective at preventing the death of E. marginata. Between 45 and 89% of plants were girdled on the day of spraying. Spraying plants with 2.5 and 5 g phosphite/L when conditions were less favourable for the pathogen reduced the mortality of E. marginata for up to 10 months. E. marginata seedlings responded to damage by P. cinnamomi with the production of kino veins and woundwood. Bark lesions were in the process of being sloughed off by 7 months after inoculation in plants that remained alive. In plants of a resistant (RR) clonal line and susceptible (SS) clonal line, phosphite treatment inhibited lesion extension in stems, but lesions did not indicate the amount of stem colonised by P. cinnamomi. The pathogen was isolated from up to 17 cm beyond the lesion front in the RR clonal line. Treatments that reduced the mortality of E. marginata were 5 g phosphite/L in the RR clonal line (RR/5) and 10 g phosphite/L in the SS clonal line (SS/10). Uninoculated plants were wounded with liquid nitrogen to determine the microscopic responses to injury in the absence of the pathogen. Wound closure was achieved within 21 days of wounding, with callus formation and vascular cambium regeneration. A wound periderm separated wounded tissue from healthy tissue, adjacent to a lignified boundary zone. Two types of phellem were observed - thin-walled phellem (TnP) and thick-walled phellem (TkP). The first-formed TnP layers contained variable-shaped cells, while subsequent layers were more cubical in shape. Multiple TnP layers developed up to 42 days after wounding, with TkP cells sandwiched between the TnP layers. Genotype and phosphite treatment did not affect the wound responses. Inoculated plants with a restricted lesion extension also formed a wound periderm to separate damaged tissue from healthy tissue. Phosphite treatment stimulated the responses to P. cinnamomi in both clonal lines. Early development of the wound periderm was visible by 6 days after phosphite treatment. It waspreceded by the formation of a ligno-suberised boundary zone in the cambial zone and in phloem parenchyma cells existing prior to injury. Suberin was not detected in the SS/0 treatment. TnP layers completely surrounded lesioned tissue in plants still alive by 24 days after phosphite treatment. Extensive callus production was evident in the SS/10, RR/5 and RR/10 treatments. Temperature affected the post-inoculation efficacy of phosphite and anatomical responses of E. marginata. At 20 degrees C lesion extension was restricted in both clonal lines of E. marginata, irrespective of phosphite treatment. Greater than 70% of inoculated plants in all treatments produced a ligno-suberised boundary zone at 20 degrees C and between 30 and 70% formed a wound periderm. At 28 degrees C, lesion extension was reduced in phosphite-treated plants at 7 days after treatment. However, lesions continued to extend up to 5 mm per day in the SS clonal line and very few SS plants formed a wound periderm at the lesion front. This contrasted with the strong responses to abiotic wounding observed in uninoculated SS plants at 28 degrees C. The most extensive responses to P. cinnamomi were detected in the RR/5 treatment at 28 degrees C, with a ligno-suberised boundary zone and differentiated TnP of a wound periderm observed in greater than 70% of plants. This treatment resulted in significantly less girdled plants than all other treatments at 28 degrees C, including the RR/0 treatment. At 23 and 24 degrees C, there was no significant difference in acropetal lesion extension or circumferential lesion spread between clonal lines. The inoculation technique and environmental conditions may have resulted in too high a disease pressure for a full expression of resistance in the RR clonal line. This thesis demonstrates that phosphite has the potential to enhance the resistance of young E. marginata and enable them to survive infection by P. cinnamomi. However, its effectiveness is dependent upon a number of factors, including host resistance, environmental conditions, the applied phosphite concentration and the timing of application.

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32

Pilbeam, Ros. "Effects of phosphite on disease development and histological responses in Eucalyptus marginata infected with Phytophthora cinnamomi." Murdoch University, 2003. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20040820.140206.

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Phosphite is currently used for the management of Phytophthora cinnamomi in native plant communities. A greater understanding of how phosphite affects the host-pathogen interaction is required in order to determine the most effective treatment. This thesis aimed to investigate the effects of applied phosphite concentration on phytotoxicity, in planta concentration of phosphite, disease development and anatomical responses of Eucalyptus marginata. Spraying the foliage to run-off with 7.5 and 10 g phosphite/L led to the development of severe leaf necrosis within 7 days, with greater than 60% of the leaf area damaged. Moderate phytotoxicity was observed after treatment with 5 g phosphite/L. In planta concentration of phosphite in stems, lignotubers and roots did not differ significantly between applied concentrations of phosphite. Stem tissue contained the largest concentration of phosphite at one week after spraying, with approximately 210 and 420 µg phosphite/g dry weight detected after treatment with 5 and 10 g phosphite/L, respectively. In a subsequent field trial, the applied concentration of phosphite was found to affect the duration of effectiveness of phosphite in protecting E. marginata seedlings from stem colonisation by P. cinnamomi. Plants were wound-inoculated with P. cinnamomi at 6-monthly intervals after spraying with phosphite. The 2.5 and 5 g phosphite/L treatments were effective against colonisation by P. cinnamomi when inoculated 0 and 6 months after spraying, but only the 5 g phosphite/L treatment inhibited P. cinnamomi within 12 months of spraying. Phosphite had no effect on colonisation by P. cinnamomi when plants were inoculated at 17 months after spraying. The in planta concentration of phosphite detected in the leaves, stems and roots of plants treated with 5 g phosphite/L did not differ significantly between the time of harvest or tissue type at 0.2 and 6 months after spraying. P. cinnamomi remained viable in plants treated with phosphite.Treatment with 2.5 and 5 g phosphite/L when P. cinnamomi was well established in the stems was ineffective at preventing the death of E. marginata. Between 45 and 89% of plants were girdled on the day of spraying. Spraying plants with 2.5 and 5 g phosphite/L when conditions were less favourable for the pathogen reduced the mortality of E. marginata for up to 10 months. E. marginata seedlings responded to damage by P. cinnamomi with the production of kino veins and woundwood. Bark lesions were in the process of being sloughed off by 7 months after inoculation in plants that remained alive. In plants of a resistant (RR) clonal line and susceptible (SS) clonal line, phosphite treatment inhibited lesion extension in stems, but lesions did not indicate the amount of stem colonised by P. cinnamomi. The pathogen was isolated from up to 17 cm beyond the lesion front in the RR clonal line. Treatments that reduced the mortality of E. marginata were 5 g phosphite/L in the RR clonal line (RR/5) and 10 g phosphite/L in the SS clonal line (SS/10). Uninoculated plants were wounded with liquid nitrogen to determine the microscopic responses to injury in the absence of the pathogen. Wound closure was achieved within 21 days of wounding, with callus formation and vascular cambium regeneration. A wound periderm separated wounded tissue from healthy tissue, adjacent to a lignified boundary zone. Two types of phellem were observed thin-walled phellem (TnP) and thick-walled phellem (TkP). The first-formed TnP layers contained variable-shaped cells, while subsequent layers were more cubical in shape. Multiple TnP layers developed up to 42 days after wounding, with TkP cells sandwiched between the TnP layers. Genotype and phosphite treatment did not affect the wound responses. Inoculated plants with a restricted lesion extension also formed a wound periderm to separate damaged tissue from healthy tissue. Phosphite treatment stimulated the responses to P. cinnamomi in both clonal lines. Early development of the wound periderm was visible by 6 days after phosphite treatment. It waspreceded by the formation of a ligno-suberised boundary zone in the cambial zone and in phloem parenchyma cells existing prior to injury. Suberin was not detected in the SS/0 treatment. TnP layers completely surrounded lesioned tissue in plants still alive by 24 days after phosphite treatment. Extensive callus production was evident in the SS/10, RR/5 and RR/10 treatments. Temperature affected the post-inoculation efficacy of phosphite and anatomical responses of E. marginata. At 20°C, lesion extension was restricted in both clonal lines of E. marginata, irrespective of phosphite treatment. Greater than 70% of inoculated plants in all treatments produced a ligno-suberised boundary zone at 20°C and between 30 and 70% formed a wound periderm. At 28°C, lesion extension was reduced in phosphite-treated plants at 7 days after treatment. However, lesions continued to extend up to 5 mm per day in the SS clonal line and very few SS plants formed a wound periderm at the lesion front. This contrasted with the strong responses to abiotic wounding observed in uninoculated SS plants at 28°C. The most extensive responses to P. cinnamomi were detected in the RR/5 treatment at 28°C, with a ligno-suberised boundary zone and differentiated TnP of a wound periderm observed in greater than 70% of plants. This treatment resulted in significantly less girdled plants than all other treatments at 28°C, including the RR/0 treatment. At 23 and 24°C, there was no significant difference in acropetal lesion extension or circumferential lesion spread between clonal lines. The inoculation technique and environmental conditions may have resulted in too high a disease pressure for a full expression of resistance in the RR clonal line. This thesis demonstrates that phosphite has the potential to enhance the resistance of young E. marginata and enable them to survive infection by P. cinnamomi. However, its effectiveness is dependent upon a number of factors, including host resistance, environmental conditions, the applied phosphite concentration and the timing of application.

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33

Lalor, Briony Maree. "An assessment of the recovery of the microbial community in jarrah forest soils after bauxite mining and prescription burning." University of Western Australia. School of Earth and Geographical Sciences, 2009. http://theses.library.uwa.edu.au/adt-WU2010.0037.

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[Truncated abstract] Recovery of soil nutrients, microbial populations and carbon (C) and nitrogen (N) cycling processes are critical to the success of rehabilitation following major ecosystem disturbance. Bauxite mining represents a major ecosystem disturbance to the jarrah (Eucalyptus marginata) forest in the south-west of Western Australia. Mining has created a mosaic of mined areas in various stages of succession surrounded by non-mined forest areas. Initial site preparations within rehabilitation areas such as contour ripping alter soil structure (creation of mound and furrows) and over time also influence the distribution of vegetation and litter. Current performance criteria developed by industry, government and other stakeholders have determined that before post-bauxite mined areas of jarrah forest can be integrated back into normal forest management practises they should be functional and demonstrate resilience to normal forest disturbances such as fire. Furthermore, resilience should be of a manner comparable to non-mined analogue forest sites. Currently little is known of the resilience of microbial communities and C and N cycling in rehabilitation sites to normal forest disturbances such as prescription burning. As such, before rehabilitated jarrah forests can be successfully integrated into broad scale forest management regimes, a more thorough knowledge of the potential impacts of burning practises on the soil microbial community and C and N cycling processes in these systems is required. ... While there are similar rates of C and N cycling the underlying microbial community structure was distinctly different; implying a high degree of functional redundancy with respect to C and N cycling. Differences in the C and N cycling and structure of the microbial communities were likely to be due to differences in soil environmental conditions (i.e. soil alkalinity/acidity, soil moisture) and C substrate availability which influence the physiological status of the microbial community and in turn are related to successional age of the forests. Results also suggest that the measurement of CLPP can be a useful approach for assessment of changes in the functional ability of microbial communities. However, the interpretation of how well these rehabilitation forests have recovered heterotrophic abilities was greatly affected by the methodological approach used (e.g. MicroRespTM or Degens and Harris, 1997). Importantly, results from Chapter 4 and 5 suggested that the effects of a moderate prescription fire on C and N processes, CLPP and microbial community structure of 18 year old rehabilitation forests are likely to be short-lived (< 2 years). Furthermore, the effects of the moderate spring prescription fire were not large enough to decouple C and N cycling processes over the short-term (< 1 years) which suggests that by 18 years of age rehabilitation forests demonstrate comparable functional resilience to a moderate prescription burn.

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34

Strehlow, Karin Henriette. "The immediate impacts of timber harvesting on terrestrial invertebrates inhabiting medium rainfall jarrah forest in south-west Western Australia." Thesis, Strehlow, Karin Henriette (2002) The immediate impacts of timber harvesting on terrestrial invertebrates inhabiting medium rainfall jarrah forest in south-west Western Australia. PhD thesis, Murdoch University, 2002. https://researchrepository.murdoch.edu.au/id/eprint/51985/.

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The ground-dwelling invertebrate fauna of medium rainfall jarrah forest was surveyed in three forest blocks (Kingston, Warrup and Winnejup) approximately 25 km north-east of Manjimup in the south-west of Western Australia. Invertebrates were collected by means of pitfall traps on 18 sampling occasions over a period of 22 months (May 1994-March 1996). Approximately 500 000 invertebrates were collected from thirty-five Classes, sub Classes or Orders. The Blattodea, Orthoptera and Araneae were further identified to morphospecies and males and females were distinguished. The forest litter invertebrate community was dominated by Collembola (springtails) (60.8% of total abundance), the Formicidae (ants) (16.8%), Diptera (flies) (6.1%) Coleoptera (beetles) (4.7%) Apocrita (wasps), (2.8%), Araneae (spiders) (2.6%) Acarina (mites) (2.0%) Hemiptera (true bugs) (1.4%) Blattodea (cockroaches) (0.4%) and Orthoptera (crickets and grasshoppers) (0.4%). These accounted for 98% of the total abundance. Of the three taxa identified to morphospecies, spiders were the most diverse, with 31 families and 108 morphospecies present, followed by the grasshoppers and crickets with 3 subfamilies and 67 morphospecies and the cockroaches with 4 families and 32 morphospecies. Six arachnid families (the Actinopidae, Idiopidae, Micropholcommatidae, Nemesiidae, Orsolobidae and Toxopidae) with Gondwanan affinities were present. Marked seasonal trends were present, with overall invertebrate activity (excluding Collembola) highest during spring and lowest during winter. The main factors affecting activity were temperature and rainfall. Changes in the numerical dominance of the taxa occurred between seasons and between years. Marked spatial variability was also evident and appeared to be associated with changes in microclimatic conditions and small-scale spatial variations in habitat. The responses of these invertebrate communities to timber harvesting practices (clearing without post-harvest burn) were examined as part of a larger integrated study (the Kingston Project) conducted by the Western Australian Department of Conservation and Land Management (CALM). A modified BACI (Before/After Control/Impact) design was used. Twenty sites, 8 Internal Controls, 4 External Controls and 8 Impact sites were sampled simultaneously before and after logging. Sampling was undertaken on 8 occasions prior to logging and 10 following logging. Logging occurred between March and April 1995. No significant impacts on total invertebrate abundance and richness were observed after logging. Moreover, only five taxa, Blattodea, Coleoptera, Diptera, Hemiptera and Orthoptera, showed significant changes in abundance, with Blattodea being the most severely affected. Impacts detected by ordination were also of short duration, with post-logging communities resembling those of undisturbed sites after 10 months. Retrospective power analysis revealed that the experimental design used had sufficient power (0.8+) to detect a 30-40% change in total invertebrate abundance. Moreover, the design had power to detect changes of 10-50% for most taxa. Identification of three taxa to morphospecies revealed significant effects of logging, not only on the taxa found to be sensitive to this disturbance (Blattodea and Orthoptera), but also in Araneae, which had shown no impacts at the level of Order. However, for spiders at least, identification to the level of family was preferable to morphospecies as the impacts of logging were masked by environmental noise at those resolutions. The impact of logging on these assemblages was also only of a short duration. Logged sites followed the same seasonal patterns as control sites in the ordination plots, indicating that seasonal and inter-annual climatic changes appear to be more important determinants of community structure and function than a logging event.

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Schild, Dorothy E. "The survival of Phytophthora cinnamomi rands in the northern jarrah (Eucalyptus marginata donn ex sm.) forest of Western Australia." Thesis, Schild, Dorothy E. (1995) The survival of Phytophthora cinnamomi rands in the northern jarrah (Eucalyptus marginata donn ex sm.) forest of Western Australia. PhD thesis, Murdoch University, 1995. https://researchrepository.murdoch.edu.au/id/eprint/52616/.

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The introduced soil-borne plant pathogen Phytophthora cinnamomi Rands causes the death ofjarrah (Eucalyptus marginata Donn ex Sm.) and associated understorey species throughout the jarrah forest of south-west Western Australia. In comparison to other infested forests in Australia, it has been difficult to isolate this pathogen from upland sites. Two aspects of survival of￡. cinnamomi on upland sites in the northern j arrah forest were examined, firstly, the survival of chlamydospores in surface soils, and secondly, the survival of E. cinnamomi in a common susceptible understorey species, Banksia grandis Willd. Chlamydospores of B. cinnamomi were recovered from a lowland water gaining site, but not from an adjacent upland freely draining site at Deer Road, although there was dying vegetation on both sites. Soil moisture contents were significantly higher on the lowland site than on the upland site (P<0.001), and remained high over summer in the former but not in the latter. Axenically produced chlamydospores did not survive in field plots when soil moisture contents decreased below 6.25% or -101 kPa on an uninfested upland site at North-east Road (P<0.001). When soil moisture contents were higher, that is, during winter and early spring, chlamydospores could be recovered for up to 24 weeks. A similar pattern of survival was observed when axenically produced chlamydospores were placed into soil from the North-east Road site and maintained at four different matric potentials in the laboratory. Germination of chlamydospores and the number of chlamydospores with intact cytoplasm were significantly affected by soil moisture (P<0.001). These results confirmed that chlamydospores did not survive on upland jarrah forest sites when soils became dry over summer. Stems and large roots from eight B. grandis trees on an upland site were excavated from an active front of dying vegetation at the end of summer. E. cinnamomi was recovered from the large roots and stems from four of the dead trees, but not from two healthy trees, two decayed trees or from soil. When two other trees from different upland sites were intensively sampled, B. cinnamomi was recovered to 40 cm below ground level in the tap and large roots and to 20 cm above ground level in the stems. When inoculated B. grandis root sections were buried (6 cm depth) in field plots on the uninfested upland pure jarrah stand site, recovery of R. cinnamomi decreased after 16 weeks with the onset of summer. During summer, recovery of the pathogen was very low to nil, but increased again in autumn as rainfall increased. Recovery of R. cinnamomi from the root sections was significantly affected by soil moisture, soil temperature and rainfall (PO.OOl). In glasshouse trials, R. cinnamomi was recovered within seven days from previously uninfested upland soil which had been placed around naturally infected R. grandis stem bases. These results confirmed that infected R. grandis acts as both a reservoir, and a source of inoculum for R. cinnamomi. The management and ecological implications for the northern jarrah forest and the control of R. cinnamomi are briefly discussed.

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Al-Jarrah, Rami [Verfasser]. "Development of cooperation between flying robot, ground robot and ground station with fuzzy logic and image processing / Rami Al-Jarrah." Siegen : Universitätsbibliothek der Universität Siegen, 2015. http://d-nb.info/1076911706/34.

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37

Mijangos, Araujo Jose Luis. "Characterisation the recolonisation of Antechinus flavipes following the restoration of a production landscape and its genetic implications in the Jarrah forest." Thesis, Mijangos Araujo, Jose Luis (2015) Characterisation the recolonisation of Antechinus flavipes following the restoration of a production landscape and its genetic implications in the Jarrah forest. Masters by Research thesis, Murdoch University, 2015. https://researchrepository.murdoch.edu.au/id/eprint/27582/.

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Ecological restoration is emerging as a promising activity to contribute to biodiversity conservation. There is presently an increasing need to develop a stronger relationship between genetics and restoration. This is particularly necessary to investigate the effectiveness of restoration to maintain and conserve genetic diversity of recolonising faunal populations. This thesis investigated the links between genetics and restoration and how understanding the contribution of genetics can be used to further improve restoration outputs. A search of scientific literature identified 160 papers employing a genetic approach within a restoration context. Although genetic research in restoration is rapidly growing (59% of the identified articles were published during the last four years), I found that studies could make better use of the extensive toolbox developed by fields of applied genetics. 42% of reviewed studies used genetic information to evaluate or monitor restoration and 58% provided genetic information to guide pre-restoration decisionmaking processes. Reviewed studies suggest that restoration practitioners often overlook the importance of including genetic aspects within their restoration goals. Even though there is a genetic basis influencing the provision of ecosystem services, few studies inquired this relationship. I provide a view of research gaps, future directions and challenges in the genetics of restoration. To evaluate how restoration affects the genetic diversity and dynamics of vertebrate species, this study uses a small marsupial (Antechinus flavipes) as a model. To this end, nine nuclear microsatellites and a 565-bp sequence of the mtDNA control region were used. Antechinus flavipes individuals were sampled in three locations with different disturbances (mining/restoration, dieback infected and dieback infected/mining) to investigate whether genetic bottlenecks, dispersal barriers, adverse environmental conditions or a skewed sex ratio affects genetic diversity and gene flow of this species. The findings showed: 1. A lack of evidence for the disruption of gene flow, suggesting that current restoration practices have been effective in maintaining adequate levels of landscape connectivity in this species. 2. There is a non-significant correlation between the distribution of individual heterozygosity and environmental conditions, suggesting that conditions in restored areas do not have a negative influence on genetic diversity. 3. Non-significant results from bottleneck tests probably indicate that restored areas provide enough resources to sustain several reproducing individuals and thus avoiding founder effects. 4. Parameters of neutral genetic diversity were high in both groups of individuals sampled in restored and in unmined sites and were not significantly different. 5. No detectable reduction of genetic diversity, despite a sampling effect that resulted in a skewed sex ratio. 6. The structure of a network of mtDNA suggests that historic gene flow occurred across the three locations.

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38

Swinburn, Marnie Louise. "Grass Tree (Xanthorrhoea preissii) selection by Mardo (Antechinus flavipes leucogaster) in jarrah forest of Western Australia: relationship with time since fire." Thesis, Swinburn, Marnie Louise (2005) Grass Tree (Xanthorrhoea preissii) selection by Mardo (Antechinus flavipes leucogaster) in jarrah forest of Western Australia: relationship with time since fire. Honours thesis, Murdoch University, 2005. https://researchrepository.murdoch.edu.au/id/eprint/32601/.

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39

Ducki, Luisa C. "Soil fungi, but not bacteria, track vegetation reassembly across a 30-year restoration chronosequence in the northern jarrah forest, Western Australia." Thesis, Ducki, Luisa C. (2020) Soil fungi, but not bacteria, track vegetation reassembly across a 30-year restoration chronosequence in the northern jarrah forest, Western Australia. Honours thesis, Murdoch University, 2020. https://researchrepository.murdoch.edu.au/id/eprint/64708/.

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Plant communities have been the primary focus of ecological restoration initiatives; however, the integration of the soil microbiome has become of interest to restoration practice and theory. The inter-dependent nature of the above- and belowground biological environments has led to assumptions that reciprocal shifts in community compositions will occur in response to disturbance and restoration. Ecological restoration of post-mining landscapes within the northern jarrah forest re-instates vegetation communities that are representative of those in adjacent reference forest. The limited studies of soil microbial communities have not addressed whether these communities recover along similar trajectories to plant communities aboveground. Here, a 30-year restoration chronosequence of vegetation development was compared with that of the belowground assemblages of bacteria and fungi, identified using environmental DNA methods. Novel findings of this study highlight similarities between restoration trajectories of fungal and vegetation assemblages, though both remained distinct from reference jarrah forest compositions after 27-years. In contrast, soil bacterial assemblages in restored jarrah forest re-assembled rapidly, with substrate depth being a greater driver of composition than vegetation. Explanatory environmental variables, such as litter cover and initial fertiliser application, were significantly associated with vegetation composition. High covariance among physico-chemical factors made it difficult to establish influences of individual variables on bacterial and fungal communities. Litter depth was significantly associated with fungal composition across the restoration chronosequence, whilst available potassium was associated with both bacterial and fungal community composition. My findings add to a growing body of literature which acknowledges the rich diversity of the belowground microbial community, and the potential for their use as predictors of restoration trajectories. Future research could focus on direct associations between fungi and plant communities, such as potential for fungal inoculation to assist in the rapid reinstatement of missing plants which rely on symbiotic associations with the belowground microbiome.

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au, M. Wheeler@murdoch edu, and Margaret Wheeler. "Reproductive and Molecular Biology of Eucalyptus marginata." Murdoch University, 2004. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20040723.140250.

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This thesis examined aspects of the reproductive and molecular biology of Eucalyptus marginata (jarrah). The aims were to develop protocols for controlled pollination, that could be used in clonal orchard trees to breed jarrah seedlings that have a known genetic resistance to Phytophthora cinnamomi (dieback), for use in rehabilitation after mining and logging. An intimate knowledge of the breeding biology of jarrah was necessary to achieve this aim. The project also aimed to increase knowledge of the genetic diversity and structure of jarrah, in order to make informed decisions regarding the collection of material to be used for clonal propagation. Previous research has had little success in producing viable seed from any controlled pollinations, but clonal material resistant to P. cinnamomi has been produced using tissue culture. The question posed in this thesis was Can we improve breeding and propagation techniques of jarrah? Techniques were developed for testing of in vitro pollen viability and pollen storage, pollination and fertilisation success after controlled pollinations, including determination of stigma receptivity and development of bud isolation techniques using alfoil. The variation in female fertility between genotypes was examined. The use of paclobutrazol was explored as a method of increasing the level of viable seed production in clonal orchard trees. The use of fertiliser as well as the growth retardant was also explored to see if it increased the level of seed production even more. Genetic diversity, genetic differentiation and phylogeny within Eucalyptus marginata were examined using nuclear and chloroplast DNA analysis with Restricted Fragment Length Polymorphisms. While it was first thought that the fertilisation rate was quite low, it was confirmed that the fertilisation rate is similar to other eucalypt species. The zygote abortion rate was quite high in one clone, but one wild tree had a similar seed production rate to other eucalypt species. The zygote and endosperm appeared to be different in the clone and the wild tree observed. The level of seed production was examined in clones and wild trees and it was found that the level was often quite low, particularly in the clones (0 13% in clones, 0 18% in wild trees) in comparison with other Eucalyptus species, and varied between genotypes. The use of a growth retardant such as paclobutrazol may increase the production of viable seed, if it is applied during autumn. The results were inconclusive for the fertiliser/paclobutrazol experiment, since the paclobutrazol was applied during spring which was the worst time of year for increasing seed production. There were differences between genotypes in reaction to both the paclobutrazol and the fertiliser/paclobutrazol. Genetic diversity was moderate in comparison with other Eucalyptus species, and there was a low level of genetic differentiation between populations in the nuclear genome. No differentiation was observed between the morphologically recognised subspecies in the nuclear genome, but differentiation between the populations on the Swan Coastal Plain and populations on the Darling Plateau was seen in the chloroplast genome, indicating that there was historical separation of these two areas. The conclusions arising from this work are that while controlled pollinations are possible in Eucalyptus marginata the clones that were used in these experiments have often behaved differently to the wild trees in the time of anthesis and levels of viable seed production, and in one clone (5J119) the zygote and endosperm nuclei appeared to be very different to the zygote and endosperm nuclei of a wild tree. Further investigation is necessary to see if these differences are related to the low level of seed production observed in the clonal populations. Paclobutrazol may be worth exploring further as a means of increasing seed production. Material to be used for rehabilitation and seed orchards can be collected from a wide area in the main distribution of the species, although trees on the Swan Coastal Plain are distinct from the trees in the main forest area in the chloroplast genome.

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Seaton, Stephen. "The interaction of drought and the outbreak of Phoracantha semipunctata (Coleoptera: Cerambycidae) on tree collapse in the Northern Jarrah (Eucalyptus marginata) Forest." Thesis, Seaton, Stephen ORCID: 0000-0002-1076-6005 (2012) The interaction of drought and the outbreak of Phoracantha semipunctata (Coleoptera: Cerambycidae) on tree collapse in the Northern Jarrah (Eucalyptus marginata) Forest. Honours thesis, Murdoch University, 2012. https://researchrepository.murdoch.edu.au/id/eprint/32761/.

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The Eucalyptus longhorned borer Phoracantha semipunctata Fabricius is an endemic Cerambycid beetle to the Northern Jarrah Forest (NJF) of south-western Australia that attacks stressed trees. The population dynamics, distribution and biology of P. semipunctata in its native habitat are poorly understood. Following a recent drought event in 2010 patches ofjarrah and marri trees throughout the NJF suffered high mortality with a noticeable increase in the borer populations. The aims of the present study were to determine the effect of this drought on P. semipunctata populations in jarrah (Eucalyptus marginata Donn ex Smith) and marri (Corymbia calophylla Hill) trees across the NJF and to determine if they would attack healthy adjacent trees, when their population levels were high. The association between the health of trees and P. semipunctata infestation was determined in standing dead, dying or healthy trees located in intact and collapsed areas of forest. Life cycle stages of P. semipunctata in terms of egg clutches, neonate feeding galleries, mature larvae and pupae in heartwood and adult emergence holes were determined by felling jarrah and marri trees. Distribution of P. semipunctata across the NJF was investigated by counting adult emergence holes in the bark of standing trees dead, dying or healthy trees at a number of collapsed sites. The health of trees in collapsed areas had clearly deteriorated where 76% of trees had lost all or part of their canopy and 18% had recently died. In contrast, the health of the trees in the surrounding intact areas where 3 7% had lost all or part of their canopy and less than 1% of trees had recently died. There was a strong association between P. semipunctata infestation and the health of the trees, with the borers concentrated in trees in collapsed sites with an average of 4.5 emergence holes (m-2) of P. semipunctata for the first 2m of the tree in collapsed areas compared to an average of 0.1 emergence holes (m-2) in the healthy intact areas. Phoracantha semipunctata were attracted to trees that had lost all or part of their canopy or had died since the drought with 94% of individuals in these trees and less than 1% of P. semipunctata in healthy trees with an intact canopy. The low levels of P. semipunctata in the trees that had lost their canopy in the intact areas tends to indicate this may be the normal or 'background' level of infestation in the NJF. These background levels may increase with the occurrence of more collapsed areas under increased frequency of droughts, due to the predicted declines in rainfall in the south-west of Western Australia. Destructive sampling in April showed that infestation levels within trees were very high with a maximum of 429 emergence holes per tree for jarrah and 345 emergence holes per tree for marri. Averaged across four collapsed sites, marri had higher levels of infestation with 15.42 emergence holes (m-2) compared to jarrah with 10.55 emergence holes (m-2) for the entire tree. In jarrah and marri an increase in clutch points (i.e. oviposition sites) and more neonate larvae (i.e. number of larval tracks) resulted in a higher of number of emergence holes. Most of larvae in the heartwood had emerged at the time of sampling being low in number but were higher in jarrah compared to marri. The differences in the total P. semipunctata emergence holes (m-2) between jarrah and marri was a result of a complex interaction of tree height and diameter over bark (DOB), where number of emergence holes (m-2) decreased with height and tree species, giving a range of responses at different sites. These differences in P. semipunctata infestations between jarrah and marri varied with sites. The distribution of P. semipunctata infestations within trees were strongly associated with billet size as it varied with tree height with higher infestations of P. semipunctata occurring closer to the base of the tree where trees had a large diameter (15-22 em). Bark thickness ranged from 10-14 mm and was found to be positively correlated with billet diameter (r2 = 0.372, P

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McDougall, Keith L. "Vegetation patterns in the northern jarrah forest of Western Australia in relation to dieback history and the current distribution of Phytophthora cinnamomi." Thesis, McDougall, Keith L. (1996) Vegetation patterns in the northern jarrah forest of Western Australia in relation to dieback history and the current distribution of Phytophthora cinnamomi. PhD thesis, Murdoch University, 1996. https://researchrepository.murdoch.edu.au/id/eprint/51870/.

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Dieback, largely attributed to the fungal plant pathogen Phytophthora cimiamomi, is characterized in the northern jarrah forest by multiple deaths of many plant species, including the dominant, Eucalyptus ruarginata (jarrah), a species of great commercial importance. The wide host range of the pathogen has major implications for the biodiversity of the ecosystem. The first records of dieback in the jarrah forest were made in the 1920s. Despite the magnitude and long history of the impact in the jarrah forest, little is known about the vegetation changes that result from dieback. In this dissertation, I develop a model of vegetation change related to dieback by examining the vegetation of a range of dieback sites and relating the patterns identified to the current distribution of P. cinnamomi. The study is the first explicit investigation of floristic and structural patterns on dieback sites in the jarrah forest. Substantial floristic differences were found between dieback and unaffected vegetation. The patterns are strongly correlated with the age of the original dieback event. There was little difference, however, in the mean number of species/quadrat between dieback and unaffected vegetation. The time since the inception of dieback was estimated using aerial photography. The oldest dieback sites located had been affected prior to 1951. Of the species found less frequently on these old dieback sites, 64% had not previously been associated with P. cinnamomi infection. Some of these were assessed for their susceptibility in glasshouse pathogenicity tests. New records of susceptibility were made at the species, genus and family levels. Several species regarded as being highly susceptible to infection by P. cinnamomi were found as frequently on old dieback sites as in unaffected vegetation. Many of the species found more frequently on dieback sites were probably present at the time of the initial dieback event. Others, mostly annuals, may have been introduced from nearby vegetation types with open canopies, such as granite outcrops. If plant invasions have occurred following dieback, the small differences in species richness between dieback and unaffected vegetation may hide a great reduction in species richness due to dieback. Structural changes following dieback may have a profound effect on some species regardless of their susceptibility to infection. A spatial association with trees on dieback sites was demonstrated for a range of species. The apparent reliance of some understorey species on tree cover is discussed in relation to current theories of patch dynamics. Two methods were used to isolate P. cinnamomi from dieback sites. In situ Banksia grandis baits were more effective at detecting P. cinnamomi than ex situ baited soils, especially when P. cinnamomi was apparently rare. P. cinnamomi was frequently isolated from creek edges with a long history of dieback and from active dieback fronts but was rarely found on sloping dieback sites affected prior to 1980. It is not clear if the P. cinnamomi present on pre-1951 dieback sites has persisted there since the initial dieback event or been re-introduced from active dieback fronts upslope. Very few highly susceptible species appear to be totally eliminated by the pathogen at the time of the initial dieback event. The mass deaths at that time are followed by a period of recolonization of susceptible species with highly germinable seed. The survival of the new cohort of these species is a function of the time taken to produce another crop of seed. Susceptible species may persist on the pre-1951 dieback sites because of highly germinable seed, young reproductive age, copious seed production and animal dispersal. The rarity of P. cinnamomi on these sites must greatly contribute to their persistence. Pathogenicity testing in excised stems indicated that resistance to the movement of P. cinnamomi in plant tissue develops in jarrah populations on many dieback sites, although it is unlikely to be integral to regeneration. Evidence of resistance in other species investigated could not be found. The key elements in the model of vegetation change developed in the thesis are (i) the on-going occurrence of P. cimiamomi on dieback sites, (ii) the susceptibility of plant species to infection by P. cimiamomi, (iii) the sensitivity of plant species to structural changes, (iv) the proportion of a plant population killed, (v) the capacity of plant species for rapid recruitment after dieback, (vi) the time taken for plant species from germination to reproduction, and (vii) the capacity of plant species to invade. Stochastic factors such as fire, logging, climatic perturbations, and diseases caused by other pathogens, cannot be quantified and easily incorporated into the model. Predictions are made about the future vegetation of dieback sites, contingent on intervention by forest managers. An epidemic - recovery cycle, involving concomitant fluctuations in pathogen and host populations, has been hypothesized by some authors for sites affected by P. cimiamomi. There is evidence of such a cycle on a small scale. On a larger scale, epidemics on dieback sites in the jarrah forest may be isolated in space and time. The importance of long-term ecological studies of jarrah forest vegetation to our understanding of natural forest processes and the effects of dieback is stressed.

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O'Gara, Emer. "Infection and disease of Eucalyptus marginata (jarrah), caused by Phytophthora cinnamomi in rehabilitated bauxite mines in the south-west of Western Australia." Thesis, O'Gara, Emer (1998) Infection and disease of Eucalyptus marginata (jarrah), caused by Phytophthora cinnamomi in rehabilitated bauxite mines in the south-west of Western Australia. PhD thesis, Murdoch University, 1998. https://researchrepository.murdoch.edu.au/id/eprint/52658/.

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In a survey of rehabilitated bauxite mines m south-west Western Australia, Phytophthora cinnamomi was isolated from the collar, but not from the root system of dead and dying Eucalyptus marginata Garrah) seedlings. Surface water ponding occurs in rehabilitated mines from autumn through to spring, and infected collars were commonly associated with ponding. This suggested that P. cinnamomi infects seedlings directly through periderm at the collar. The objective of this project was to ascertain whether infection by P. cinnamomi through periderm was possible, to study the disease in seedlings infected in this manner, and the methods by which P. cinnamomi circumvented the periderm to infect the seedlings. An inoculum receptacle was designed to simulate water ponding around the main stem of jarrah seedlings, and into which zoospores could be introduced. Under controlled glasshouse conditions in December (early summer) it was demonstrated that zoospores can infect through the stems of non-wounded and wounded jarrah seedlings. This was confirmed in a rehabilitated bauxite mine in May/June (late autumn/early winter), when ponding is most prevalent and sustained. In the field trial, P. cinnamomi was isolated from stems of non-wounded and wounded seedlings 3 weeks after inoculation. However, lesions did not develop in the non-wounded seedlings, or in most of the wounded seedlings. Another field trial examined the long-term prognosis for jarrah seedlings infected by zoospores at the collar. Within 3-6 months of either winter or spring inoculations, 7% ofthe seedlings died. In a further 6% of seedlings, the inoculated shoot died but the seedling survived through coppice growth from the lignotuber. As time from inoculation increased the reisolation of the pathogen from surviving seedlings decreased. Seedlings were severely water stressed during the summer with pre-dawn xylem pressure potentials as low as -1.5 MPa. In two post-summer harvests an intensive baiting and wetting regime was required to reisolate the pathogen from inoculated seedlings. Histological studies were undertaken to investigate: the origin and nature of jarrah periderm; the effects of pending on jarrah tissue; and the methods by which P. cinnamomi invades jarrah through periderm. The production of periderm was described from its origin in the peri cycle of the roots in 4-week old jarrah seedlings, through to rhytidome production in lignotuberous seedlings and 3- to 4-year old saplings. The first periderm in jarrah stems occurred internal to the primary phloem tissue, but it eventually migrated to a more superficial position in the stem. The first periderm consisted of phellogen, phelloderm, and a single type of phellem which was thin-walled and suberised. Between sequent periderms a second type of phellem formed, the cells of which were thick-walled and lignified. The formation of spongy rhytidome occurred when secondary phloem tissue underwent gross expansion after isolation between layers of periderm. Jarrah stems took up water in the region of inundation, and there was an increase in the frequency, but not size, of intercellular spaces after 5 weeks of localised ponding. There was also an increase in size of non-tanniferous parenchyma cells, but no overall increase in stem diameter. There was a measurable quantity of soluble carbohydrates in the pond liquid after 1 week, which had significantly increased after 5 weeks. Zoospores of P. cinnamomi were attracted primarily to sites of axillary shoot emergence in jarrah stems. Rapid and extensive infection and colonisation occurred through the new tissue of the emerging axilla1y shoots. Zoospores also bound randomly to other parts of the stem and were occasionally observed to attempt intercellular penetration of thin-walled suberised phellem, but extensive infection and colonisation was not observed as a result of such interactions. Zoospores were not preferentially attracted to either stem or leaf stomata, although penetration was occasionally observed through stem stomata. Zoospores were not attracted to lenticels and there was no evidence of infection through lenticels. The results of the project are discussed in the light of a 'disease tetrahedron', where mining and rehabilitation have resulted in a highly altered environment in which the host and pathogen operate. Conditions peculiar to rehabilitated sites are discussed in terms of their ability to exacerbate or reduce disease severity.

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O'Brien, Jayden. "The persistence and survival of Phytophthora cinnamomi in low and high impact 'black gravel' sites in the Jarrah forest of south west Australia." Thesis, O'Brien, Jayden (2008) The persistence and survival of Phytophthora cinnamomi in low and high impact 'black gravel' sites in the Jarrah forest of south west Australia. Honours thesis, Murdoch University, 2008. https://researchrepository.murdoch.edu.au/id/eprint/32594/.

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Szota, Christopher. "Root morphology, photosynthesis, water relations and development of jarrah (Eucalyptus marginata) in response to soil constraints at restores bauxite mines in south-western Australia." University of Western Australia. School of Plant Biology, 2009. http://theses.library.uwa.edu.au/adt-WU2010.0058.

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Bauxite mining is a major activity in the jarrah (Eucalyptus marginata Donn ex Sm.) forest of south-western Australia. After mining, poor tree growth can occur in some areas. This thesis aimed to determine whether soil constraints, including reduced depth and compaction, were responsible for poor tree growth at low-quality restored bauxite mines. In particular, this study determined the response of jarrah root morphology, leaf-scale physiology and growth/development to soil constraints at two contrasting (low-quality and high-quality) restored bauxite-mine sites. Jarrah root excavations at a low-quality restored site revealed that deep-ripping equipment failed to penetrate the cemented lateritic subsoil, causing coarse roots to be restricted to the top 0.5 m of the soil profile, resulting in fewer and smaller jarrah trees. An adjacent area within the same mine pit (high-quality site) had a kaolinitic clay subsoil, which coarse roots were able to penetrate to the average ripping depth of 1.5 m. Impenetrable subsoil prevented development of taproots at the low-quality site, with trees instead producing multiple lateral and sinker roots. Trees in riplines, made by deep-ripping, at the high-quality site accessed the subsoil via a major taproot, while those on crests developed large lateral and sinker roots. Bauxite mining is a major activity in the jarrah (Eucalyptus marginata Donn ex Sm.) forest of south-western Australia. After mining, poor tree growth can occur in some areas. This thesis aimed to determine whether soil constraints, including reduced depth and compaction, were responsible for poor tree growth at low-quality restored bauxite mines. In particular, this study determined the response of jarrah root morphology, leaf-scale physiology and growth/development to soil constraints at two contrasting (low-quality and high-quality) restored bauxite-mine sites. Jarrah root excavations at a low-quality restored site revealed that deep-ripping equipment failed to penetrate the cemented lateritic subsoil, causing coarse roots to be restricted to the top 0.5 m of the soil profile, resulting in fewer and smaller jarrah trees. An adjacent area within the same mine pit (high-quality site) had a kaolinitic clay subsoil, which coarse roots were able to penetrate to the average ripping depth of 1.5 m. Impenetrable subsoil prevented development of taproots at the low-quality site, with trees instead producing multiple lateral and sinker roots. Trees in riplines, made by deep-ripping, at the high-quality site accessed the subsoil via a major taproot, while those on crests developed large lateral and sinker roots.

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Lee, Jessica. "Integrating conservation with production: The ecology of three threatened black cockatoos within a mining production landscape in the Jarrah-Marri forest of Western Australia." Thesis, Lee, Jessica (2013) Integrating conservation with production: The ecology of three threatened black cockatoos within a mining production landscape in the Jarrah-Marri forest of Western Australia. PhD thesis, Murdoch University, 2013. https://researchrepository.murdoch.edu.au/id/eprint/22441/.

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Three threatened black cockatoos inhabit the Jarrah Eucalyptus marginata-Marri Corymbia calophylla forest of southwestern Australia: Baudin's Cockatoo Calyptorhynchus baudinii, Carnaby's Cockatoo C. latirostris, and the Forest Red-tailed Black Cockatoo C. banksii naso (FRTBC). Their local ecology in relation to anthropogenic disturbance is poorly known, hampering conservation management. This study investigated their ecology at the Newmont Boddington Gold (NBG) mine, 130 km southeast of Perth, Western Australia, along the eastern margin of the Jarrah-Marri forest. To improve the scientific basis for conserving black cockatoos and their habitat at NBG, I aimed to: (1) describe the ecology of the three species at NBG, particularly group size, site occupancy, habitat use, and food plant use (including seasonal and interannual changes); (2) examine the effectiveness of ground-based hollow surveys, postfelling inspections of hollows, and behavioural observations for assessing black cockatoo breeding habitat; (3) assess the successional stage of the rehabilitated mine pits and characterise variation in the structure and floristics of pits, in order to identify features that might influence the availability of food resources for black cockatoos; (4) document feeding activity by black cockatoos within rehabilitated mine pits and any associations with structural or floristic features; (5) trial artificial nest hollows to support breeding on-site and compensate for the loss of natural hollows; (6) review the use of artificial nest hollows for black cockatoos to assess their value for mitigating natural hollow loss; and (7) investigate black cockatoo use of natural and artificial water sources at NBG and assess the potential for black cockatoo interactions with residue disposal areas. All three black cockatoos used remnant forest habitat as well as human-modified habitats such as mine-site rehabilitation, water sumps, farm paddocks, and pine plantations. Carnaby’s Cockatoos used the broadest range of habitats and fed on at least ten plant species at NBG. FRTBC showed similar group sizes and occupancy across seasons, suggesting year-round residency. In contrast, group size and occupancy changed across seasons for Carnaby’s Cockatoos, indicating migrating flocks as well as some birds present year-round. Few Baudin’s Cockatoos were observed in spring and summer, but they were more abundant during autumn and winter, which is when flocks migrate northwards. Three methods – ground-based surveys, post-felling inspections, and behavioural observations of black cockatoos – were used to describe the availability of potentially suitable nesting hollows across three tree species (Jarrah, Marri, Wandoo E. wandoo) and to document probable nest sites. Eleven probable black cockatoo nest hollows were identified at NBG and surrounds (Carnaby’s Cockatoos: n = 7; FRTBC: n = 3; and unknown black cockatoo species: n = 1). Behavioural observations, using visual or acoustic cues followed by physical ‘tree-knocking’, were the most effective approach to identify probable nest hollows (n = 10 hollows). Ground-based surveys yielded only one probable nest hollow, while post-felling inspections identified none, despite large sample sizes and extensive field survey periods. Of the probable nest hollows, six were in Marri, four in Wandoo, and one in Jarrah. Ground-based surveys identified 149 potential hollow-bearing trees, of which 119 (80%) survived felling intact enough for inspection. Few potential hollows in Jarrah were large enough for black cockatoos (n = 28 of 89 trees inspected, 31.5%). Large hollows occurred more frequently in Marri (n = 14 of 22 trees inspected, 63.6%) and Wandoo (n = 8 of 12 trees inspected, 66.7%). Thus ground-based surveys may significantly overestimate potentially suitable hollows, but they may provide useful assessments of relative hollow abundance if biases are identified and corrected. Post-felling inspections are ineffective at characterising hollow occupancy, but provide other data. Targeted behavioural observations are most reliable for identifying probable nest hollows, provided that surveys are undertaken at dawn and dusk during known breeding seasons. The rehabilitation pits at NBG were 7 - 10 years old and in an early successional stage, with a wide range of proteaceous vegetation. The larger myrtaceous trees were becoming prominent and will eventually shade out the proteaceous understorey. Carnaby’s Cockatoo fed on seeds and flowers from proteaceous shrubs (Banksia and Hakea spp.), while Baudin’s Cockatoo and FRTBC fed on Marri seeds. Examination of food residues proved critical in demonstrating feeding activity by FRTBC within rehabilitated mining pits, as FRTBC were not observed. No particular floristic or structural features characterised feed plots relative to non-feed plots, suggesting little support for substantially altering rehabilitation prescriptions to cater to the food requirements of black cockatoos. Rather, food availability within rehabilitated areas reflects vegetation succession, with fast-maturing proteaceous species providing abundant food in young rehabilitation sites, followed by regenerating eucalypts (e.g. Marri). Therefore, as succession proceeds and the structure (and species composition) of the vegetation becomes closer to that of the native Jarrah-Marri forest, the availability of habitat resources is likely to change. Rehabilitation of mining pits can provide shortterm benefits for black cockatoos, emphasising the broader value of revegetating landscapes to support black cockatoo conservation. However, tree hollows suitable for breeding take over a century to form, so conserving old, hollow-bearing trees complements restoring food plants. Trials of plastic and wooden artificial nest hollows (ANHs) at NBG by black cockatoos yielded no observations of inspection or nesting by black cockatoos. This likely related to ANH position (i.e. too low in the tree) or location (i.e. far from an established nesting site), and the presence of sufficient natural hollows locally. A state-wide survey of ANH use by black cockatoos in Western Australia was also undertaken. Responses indicated that ANHs have been widely used (at least 157 ANH installations) in Western Australia from as early as 1996. Three major ANH designs have been used: ‘cockatubes’, hollowed-out log sections, and wooden box-type ANHs. Black cockatoos nested and reared young in all designs. Most observations of black cockatoos using ANHs involved Carnaby’s Cockatoos. There were few records of ANHs by FRTBC and none by Baudin’s Cockatoo. Thus ANHs may present a short-term mitigation option, especially in areas deficient in natural hollows. However, over the long-term, they cannot substitute for natural hollows. Observations of black cockatoo drinking sites at NBG documented the use of both natural and man-made water sources. The site, and the surrounding landscape, provides water for black cockatoos across the year. Black cockatoos prefer water sources with firm and gently inclined edges surrounded by vegetation. They rarely came into proximity with potentially hazardous sections of the Residue Disposal Areas (RDAs). RDAs may be less attractive because they occur in very open landscapes. Black cockatoos used faunal drinking points around the RDAs, suggesting that they minimise black cockatoo-RDA interactions. Overall, the three black cockatoos exhibited different ecologies within the same landscape, differing in their responses to disturbance and their capacity to use anthropogenic resources. Significantly, the value of young rehabilitation for feeding indicates that feeding habitat can be restored on a scale of a decade or two rather than waiting for nearly a century as the forest matures. Breeding resources, however, are only restored naturally on a scale of centuries, placing a premium on conserving prime breeding habitat and artificial supplementation of the breeding hollow resource. Given that much of the remaining Jarrah-Marri forest is within the tenure of State Forest or mining companies such as NBG, there is considerable scope for adaptive management initiatives to further inform conservation actions for black cockatoos. These initiatives could investigate: (1) management of orchards; (2) captive breeding; (3) general population ecology and baseline data collection; (4) issues related to nesting hollows; (5) management issues specific to mine-sites; and (6) management issues relevant to forested areas of the southwest, in particular State Forest.

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Cargill, Jeffrey. "Fate of Eucalyptus marginata seed from canopy-store to emergence in the northern jarrah forests of Western Australia: Research to help improve regeneration following shelterwood treatment." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2014. https://ro.ecu.edu.au/theses/1415.

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The establishment of seedling regeneration is a key process in and indicator of ecologically sustainable forest management. The availability of seed and the creation of a suitable seedbed are recognised as important factors limiting seedling recruitment. A silvicultural method commonly used across northern and eastern jarrah forest blocks is shelterwood cutting. The primary objective of treating jarrah forest to shelterwood is to promote seedling regeneration in areas lacking sufficient advanced growth. Despite the widespread and progressive implementation of the shelterwood method, its application in jarrah forest has shown varying degrees of success. This thesis sought to investigate and better understand the roles of seed supply and seedbed condition in promoting successful seedling regeneration in shelterwood-treated jarrah forest. It addressed two questions from an ecological and management perspective. Firstly, could adequate seed supply and favourable seedbed conditions be effectively managed and produced in shelterwood-harvested coupes? Secondly, could adequate seed supply and suitable seedbed conditions be reliably produced to facilitate successful seedling regeneration following disturbance events, in this case post-harvest burning? A major effort was dedicated to developing a more accurate and practical method of assessing seed crops in individual trees. The final model produced a high degree of predictability (R² = 0.85), while still maintaining a high level of practicality for field application, with three easily measured variables being used (stem diameter combined with subjective assessments of capsule clump density and capsule clump distribution). The refined model dramatically improved estimates of crown capsule numbers from the previous model, with the R² value increasing from 0.29 to 0.85. The second major focus of the study was to assess the capacity of prescribed burns, under mild conditions, to produce seedbed conditions suitable for regeneration. Low intensity prescribed burns resulted in the production of suitable conditions for seedling regeneration; that is, leaf litter and understorey vegetation were reduced and ash beds were created. Ash bed production was heterogeneous within sites. This heterogeneity has been attributed to the capacity of low intensity prescribed burns to account for fine-scale variations in fuel quantity, continuity and condition. Patterns of pre-burn aerial seed crop size and seed fall following low intensity prescribed burning were also assessed. Canopy capsule crops showed a high degree of spatial and temporal variability, both in terms of seed quantity and maturation. Such variability has been attributed to individual trees or groups of trees responding differently to localised climatic events and/or interspecific site factors at each stage of the flowering cycle. The main source of this variability was shown to be the numbers and spatial distribution of super trees; that is, trees defined as having a stem diameter >60 cm and >20 000 capsules. The average rate of seed fall increased substantially following prescribed burning under mild conditions. Postharvest burning under the mild conditions of the current survey did not result in en masse seed fall. Rather, peaks in seed fall were observed in the first few weeks post-burn, followed by low level falls throughout the following year. Sites burnt in spring showed a higher and more consistent release of seed in the first few weeks following fire, whereas seed fall after autumn burning was more sporadic. The comparative and interactive roles that seed supply and seedbed conditions play in limiting recruitment of jarrah were also studied. Low seedling densities were recorded across all six burnt study sites. The fact that ample levels of post-burn seed fall produced such low seedling numbers suggested that adequate seed supply did not coincide with seedbed conditions suitable for mass seedling regeneration. Conditions favourable for seedling recruitment were highly variable within sites, since both seed supply and seedbed conditions were spatially heterogeneous. Fine-scale areas burnt to mineral soil showed an additive influence to the overwhelmingly dominant factor of seed supply on seedling recruitment. However, the capacity of low intensity burns to produce these seedbed conditions at a broad scale is limited. Results of this study suggest that successful stocking of shelterwood-treated jarrah forest is not always achievable following a disturbance event, such as post-harvest burning under mild conditions. The chances of a large seed supply coinciding with broad-scale seedbed conditions favourable for mass germination, emergence and establishment appear to be low. Successful stocking of shelterwood-treated jarrah forest is more likely to be a longer term outcome achieved through episodic recruitment, when favourable environmental conditions coincide with optimal seedbed conditions. Such episodic recruitment strategies may be common in resource-limited systems such as jarrah forest and other dry eucalypt forest systems, where conditions controlling the regeneration niche are often variable and unpredictable.

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48

Weerheim, Marieke S. "Distribution patterns and habitat use of black cockatoos (Calyptorhynchus spp.) in modified landscapes in the south-west of Western Australia." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2008. https://ro.ecu.edu.au/theses/126.

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Conservation planning for animal species inhabiting modified landscapes requires understanding of where animals occur and how they utilise both natural and modified habitats. In this study the distribution and foraging behaviour of the forest red-tailed cockatoo (Calyptorhynchus banksii naso), Baudin’s cockatoo (C. baudinii) and Carnaby’s cockatoo (C. latirostris) was investigated in three study areas which each contained a different combination of modified habitats. Pickering Brook contained native forest and orchards, Wungong contained a mosaic of native forest and revegetation, while Karnet contained primarily native forest and paddocks. The relationship between cockatoo distribution and land use types was examined by constructing Generalised Linear Models based on bird counts and land use data along 90.5 km of road transects. The Akaike Information Criterion (AIC) was used to select a set of the most parsimonious candidate models. Models were constructed at two scales: Regional models incorporated the datasets of all three study areas, while study area models used the datasets of single study areas. Models for the forest red-tailed cockatoo indicated selection against young post-1988 revegetation. This response was apparent at both the regional scale and within the Wungong study area. Baudin’s cockatoo selected in favour of orchards at the regional scale, but their distribution was unrelated to any land use variable within the (orchard-rich) Pickering Brook study area. No models were constructed for Carnaby’s cockatoo due to a limited number of observations for this species. Feeding observations demonstrated the importance of the native eucalypts marri (Corymbia calophylla) and jarrah (Eucalyptus marginata) as a food source for the forest red-tailed cockatoo and Baudin’s cockatoo. In contrast Carnaby’s cockatoo fed most frequently in plantations of introduced pine (Pinus spp.). Contrary to model predictions, Baudin’s cockatoo was never observed feeding in apple orchards during the study. This discrepancy may be due to timing of the surveys outside the hours when Baudin’s cockatoo fed in orchards, or it could indicate that orchards are of limited importance as a food source. Forest red-tailed cockatoos consistently fed on particular marri trees while ignoring others, but this selectivity was unrelated to fruit morphology or seed nutrient content. Instead, foraging patterns may have been driven by ingrained habits, or by variation in the concentration of secondary compounds. iv In conservation efforts, identification of critical habitats is an important first step. This study highlighted the importance of studying habitat selection and constructing management plans at an appropriate scale, relative to the range of the target species. Wide ranging species like black cockatoos require regional scale protection of important broad vegetation types such as the northern jarrah forest, combined with landscape scale protection and restoration – for instance during postmining revegetation – of specific feeding habitat and food species, such as pine for Carnaby’s cockatoo and possibly Fraser’s sheoak (Allocasuarina fraseriana) for the forest red-tailed cockatoo.

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49

Weiss, Stefan. "Die Musik Philipp Jarnachs /." Köln-Rheinkassel : C. Dohr, 1996. http://catalogue.bnf.fr/ark:/12148/cb35869918d.

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50

Nascimento, Servio Ricardo da Silva. "Relatório final do projeto Mr. Jarbas." reponame:Repositório Institucional do BNDES, 2014. https://web.bndes.gov.br/bib/jspui/handle/1408/10694.

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Este trabalho propõe a implantação de um novo negócio e sua origem remonta os estudos desenvolvidos na disciplina de Empreendedorismo, do MBA e Gestão de Negócios, do IBMEC, entre setembro e outubro de 2013. Naquela ocasião, foi solicitado ao grupo formado citar um problema percebido em seu cotidiano, que pudesse apresentar uma solução, inicialmente, capaz de se tornar um novo negócio ou uma melhoria de processo. A partir daí, uma série de estudos foram realizados de forma a subsidiar a construção deste novo negócio, aplicando ferramentas obtidas durante o MBA, sobretudo o BMG Canvas. O resultado foi o primeiro passo para um Plano de Negócios que deve aprofundar-se em aspectos estratégicos e financeiros para ratificar a viabilidade do negócio.
TCC (MBA em Gestão de Negócios) - Ibmec Business School, Rio de Janeiro, 2014
Bibliografia: p. 23

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