Gotowa bibliografia na temat „Forest ecology – Western Australia – Perth Region”

The Gnangara Mound is an area of elevated sandy soil on the Swan Coastal Plain to the north of Perth. It constitutes a major groundwater resource for metropolitan Perth. Sixteen wetlands on the Mound had total phosphorus concentrations of 12-462�g L-1, the high values being attributed to agricultural and urban activity. Sediment concentrations of total phosphorus and total nitrogen were 61-954 and 1212-16739 �g g-1, respectively. Conductivities were 505-10270 �S cm-1, and pH values were 3.3-9.3. Only one wetland was highly coloured (79.9 8440 m-1), with an E4/E6 ratio of 4.6. Chlorophyll a concentrations were 0.01-130.8�g L-1; in wetlands with low gilvin concentrations, Myxophyceae dominated, whereas wetlands with higher gilvin concentrations had large numbers of diatoms and Chlorophyceae. The highly coloured wetland had the lowest chlorophyll a concentration despite high nutrient concentrations, supporting the hypothesis that the consequent reduction in light or other associated factors are important in maintaining low phytoplankton biomass in dystrophic wetlands of the region, particularly those on Bassendean sands.

In January 1989, a wildfire burnt 120 ha (45%) of the 267 ha of native vegetation in Kings Park, Perth, Western Australia. The area burnt included a transect along which birds had been censused during 1986 for comparison with censuses on the same transect during 1928–37 and 1952–55. Counts of birds along the transect from 1989 to 1995 indicate a slow recovery in numbers for 11 (38%) of 29 species present in 1986. Two species disappeared from the transect, but one of these was found elsewhere in the park. There are many reasons for the changes in the avifauna of Kings Park, including changes to the structure of the vegetation, the increasing isolation of the park from other native vegetation, and changes in the distribution and abundance of species outside the Perth region. The long-term trends in the avifauna and the impact of the 1989 fire indicate that a new approach to the management of the Park’s vegetation may be required. For example, to avert continuing declines in the Park’s avifauna, it may be helpful to re-establish a canopy of eucalypts and to create a more open understorey with some bare ground. However, the impact of the 1989 fire and the slow recovery of the avifauna illustrate the sensitivity of small reserves to major disturbances and the difficulty of conserving the original biota without intensive intervention.

This paper presents the background for a series on the biology of small mammals in the Mitchell Plateau region, an area characterised by a wet-dry tropical climate. From June 1981 to December 1982, 19 species of small terrestrial mammals were captured at Mitchell Plateau. Of 17 species captured on eight mark-release grids, 13 clustered into four significant groups which reflected the major habitats of the region: (1) Sminthopsis virginiae, Leggadina sp. and Pseudomys nanus in riparian and plateau escarpment sites; (2) Phascogale tapoatafa, Trichosurus arnhemensis and Pseudomys laborifex in plateau open forest; (3) Conilurus penicillatus and Mesembriomys macrurus in open woodland and coastal mosaics; (4) the commoner species Dasyurus hallucatus, Isoodon macrourus, Melomys sp. cf. burtoni, Zyzomys argurus and S. woodwardi in an array of habitats. Rattus tunneyi, Pseudantechinus sp., Wyulda squamicaudata and Planigale maculata did not cluster significantly with other species. Two species, Pseudomys delicatulus and Mesembriomys gouldii, were represented by single specimens captured outside the capture-mark-release grids, in sandstone and plateau woodland respectively. Open forests, particularly on the lateritic plateau surfaces, had the richest and most diverse mammal assemblage over the entire study period. The vine thickets and sandstone contained relatively stable populations of fewer species, and several habitats had seasonally variable populations and species.

The Gnangara Mound is a 2,200 km 2 unconfined aquifer located in the Swan Coastal Plain of Western Australia. This aquifer is one of the most important ground water resources for the Perth Region and supports a number of groundwaterdependent ecosystems, such as the springs of Ellen Brook and root mat communities of the Yanchep Caves. Although freshwater copepods have been documented previously from those caves and springs, their specific identity were hitherto unknown. The current work formally identifies copepod samples collected from 23 sites (12 cave, three bore, five spring and three surface water localities) within the Gnangara Mound region. Fifteen species were documented in this study: the cyclopoids Australoeucyclops sp., Eucyclops edytae sp. nov., Macrocyclops albidus (Jurine, 1820), Mesocyclops brooksi Pesce, De Laurentiis & Humphreys, 1996, Metacyclops arnaudi (G. O. Sars, 1908), Mixocyclops mortoni sp. nov., Paracyclops chiltoni (Thomson, 1882), Paracyclops intermedius sp. nov. and Tropocyclops confinis (Kiefer, 1930), and the harpacticoids Attheyella (Chappuisiella) hirsuta Chappuis, 1951, Australocamptus hamondi Karanovic, 2004, Elaphoidella bidens (Schmeil, 1894), Kinnecaris eberhardi (Karanovic, 2005), Nitocra lacustris pacifica Yeatman, 1983 and Paranitocrella bastiani gen. et sp. nov. Tropocyclops confinis is recorded from Australia for the first time and A. (Ch.) hirsuta and E. bidens are newly recorded for Western Australia. The only copepod taxa endemic to the Gnangara Mound region are E. edytae sp. nov. (occurs primarily in springs and rarely in the Yanchep National Park Caves) and P. bastiani gen. et sp. nov. (confined to the Yanchep National Park Caves containing tuart root mats). Paracyclops chiltoni was the most common species, whilst T. confinis and N. l. pacifica were rarely encountered. Metacyclops arnaudi was the only taxon absent from ground waters. The copepod fauna recorded in the caves and springs of the Gnangara Mound region are comparable, with respect to species richness, endemicity and the varying degrees of dependency on ground water, to those reported from similar habitats in South Australia and Western Australia. Restoring the root mats and maintaining permanent water flow within the Yanchep Caves, as well as minimising urban development near the Ellen Brook Springs, are essential to protect the copepod species, particularly the endemic P. bastiani gen. et sp. nov. and E. edytae sp. nov., inhabiting these unique ground water environments.

Phylogeographic patterns in the cp genome of Eucalyptus marginata Don ex Sm., a species common in the mesic region of south-western Australia, were investigated by using RFLP analysis. The chloroplast diversity was structured into two geographically distinct lineages and nested clade analysis inferred historical fragmentation as the major influence on the phylogeographic pattern. The lineages were separated along the geomorphological boundary of the Darling Scarp, which separates the Coastal Plain from the Darling Plateau. The divergence between the lineages is consistent with uplifting of the Darling Plateau in the late Neogene. Further geographic structuring in haplotype distributions was evident in the forest lineage on the Darling Plateau, where one sublineage was present in the central forest region and another was restricted to the south-eastern region. The level of divergence between these sublineages was similar to that between divergent lineages that have been identified in comparative phylogeographic studies of cpDNA variation in three species widespread throughout south-western Australia. In these species, divergence was attributed to the influence of significant changes in climatic oscillations across the semi-arid region during the mid-Pleistocene. The divergence identified in this study indicates that the influence of climatic change was widespread throughout south-western Australia, including the mesic, higher-rainfall region.

After over 50000 years of interaction between Aboriginal people and changing climates, south-western Australia’s tall forests were first logged less than 200 years ago, initiating persistent conflict. Recent conservation advocacy has resulted in the protection of 49% of these tall forests in statutory reserves, providing an opportunity to implement and benefit from a growing moral consensus on the valuing of these globally significant, tall forest ecosystems. We analysed a cross-section of literature (63 papers, 118 statements) published on these forests over 187 years to identify values framing advocacy. We differentiated four resource-oriented discourses and three discourses giving primacy to social and environmental values over seven eras. Invasion sparked initial uncontrolled exploitation, with the Forests Act 1918 managing competing agricultural and timber advocacy. Following the Colonial and Country Life eras, industrial-scale exploitation of the karri forest region resulted in reaction by increasingly broad sectors of society. Warming and drying in the 21st Century emphasises the importance of intact tall forest and the Indigenous Renaissance discourse. Vesting for a more comprehensive set of values would acknowledge a new moral consensus.

Life history patterns of thirteen species of invertebrates from streams of the northern jarrah forest were examined over a 1-year period. Five species had univoltine cycles with a single cohort and demonstrated a high degree of synchrony of larval development and a restricted period of adult emergence. Two species of Leptophlebiidae also had univoltine cycles but showed the more typical pattern of Australian mayflies, with extended recruitment, multiple overlapping cohorts and a long period of adult emergence. Uroctena sp., a small gammarid, had a generation time of 1 year but showed considerable spatial variation in the degree of synchrony of development. This appeared to be a result of differences in the constancy of stream discharge and was not attributable to differences in the temperature regime of the streams. At least three species demonstrated cohort splitting which resulted in an apparently bivoltine cycle. A life-history pattern of alternating long and short development times is described which, on average, would produce two generations every 3 years. This is considered to be a highly adaptive strategy for Australian stream insects with slow life cycles and can explain the extended periods of recruitment and adult emergence so often observed. Streams of the northern jarrah forest are depauperate compared with other Australian streams, despite predictable temperature and discharge regimes. The insular nature of the south-west Bassian region and its long period of isolation may be the principle cause of this reduced diversity. The invertebrate community of these streams is simple in structure and has a high degree of seasonality that is atypical of the temperate streams of Australia and New Zealand.

Little is known of the breeding behaviour of the Forest Red-tailed Black Cockatoo Calyptorhynchus banksii naso (FRTBC), a large, iconic forest cockatoo, endemic to the south-west corner of Western Australia, currently listed as Vulnerable under the State Western Australian Wildlife Conservation Act and under the Commonwealth Environment Protection and Biodiversity Conservation Act. In this paper, we provide details of breeding behaviour of FRTBC based on observations throughout the year over 17 years, together with observations of diet and feeding behaviour over the same period. FRTBC are monogamous hollow-nesters. Breeding was recorded in all months, with peaks in autumn-winter (April– June) and spring (August–October), with few records in January and February. Breeding also varied between years, with little breeding in 1999, 2001 and 2008, but many observations in 2006 and 2009. Breeding occurred at times of fruiting of either of the principal feed trees, Jarrah Eucalyptus marginata or Marri Corymbia calophylla, so it does not depend solely on one or the other of these species. Courtship displays were noted at all times of the day, from before dawn at roost sites to dusk. In total, 205 breeding events were recorded, of which 69 (93%) of 72 nests had breeding confirmed on a second visit. Use of particular nest hollows varied considerably, with some used only once and some up to seven times. Only one egg is laid, which the female incubates for 29 to 31 days, before a nestling hatches weighing between 27 and 32 g. The female remains in the hollow during incubation and only leaves for a short period in the evening to be fed by the male, usually at dusk. The chicks are brooded for up to 10 days, after which the female leaves the nest between dawn and dusk. Pairs of birds appear to recognise each other by calls, not responding to calls by others in the area. Chicks only respond when the parent is heard. Chicks are fully feathered at 48 days. Fledgling success was estimated at 60%. Juveniles remain dependent on the adults 18 months to 2 years. Thirty-seven chicks were banded between 1997 and 2011. Juvenile-immature birds moved on average less than 3 km from their natal tree and older birds were observed moving up to 19 km. This suggests that FRTBC are generally sedentary. Immature birds took up to three times as long as their parents to open Jarrah or Marri nuts and eat the seeds. In recent years there has been an interesting change in foraging behaviour of birds in the northern Darling Range (adjacent to the Perth metropolitan area) with the FRTBC discovering and using a new food source, the introduced Cape Lilac Melia azedarach, and this species is of growing importance as food in the Perth region. In combination, the data on breeding biology and diet highlight the importance of identifying recruitment rates and food availability in managing populations of FRTBC.

The Australian sea-lion, Neophoca cinerea, has a 17-18-month breeding cycle on islands off the west coast of Western Australia. Buller, North Fisherman and Beagle Is are the main pupping sites, with several very small colonies (n> 3) at the Abrolhos Is. The 4-5-month pupping seasons are synchronised at North Fisherman and Beagle Is, but the sea-lions from Buller I. breed one month later and those from the Abrolhos Is two months earlier. Pup production and pup mortality were highly variable between seasons over which observations were recorded: 129 pups were born at the main breeding sites in early 1988, the mortality in the first five months was 7.1%, whereas 181 pups were born in late 1989 of which 24.3% died. Pups remain in the vicinity of their natal islands for the first 4-5 months of life before leaving, perhaps on foraging trips, with their mothers. Most return to their natal island, although others haulout on islands up to 27 km away. Some male N. cinerea congregate in bachelor colonies on islands adjacent to the Perth metropolitan region during the non-breeding season and migrate up to 280 km north each breeding season. The status of the isolated, west-coast N. cinerea population is unknown. The current high level of human pressure on sea-lion terrestrial habitats and their food resources indicate a need for further monitoring of this species.

Rufous treecreepers (Climacteris rufa) are common in southern jarrah forests of Western Australia, but nothing has been recorded of their ecology in the region. I investigated the foraging and nesting ecology of the species in the southern jarrah forests from January 1994 to April 1996. Rufous treecreepers foraged exclusively on two eucalypt species, jarrah and marri, and foraged on trees that were significantly larger and taller than random. Foraging on the ground, logs and fallen trees was relatively infrequent. Nest hollows were also located exclusively in jarrah and marri trees that were significantly larger and taller than random. The important foraging and nesting resources for the species in the southern jarrah forest appear to be large mature and overmature eucalypts. Anthropogenic impacts in the region, primarily logging, should aim to retain these resources in affected areas to improve the survival prospects of the species. When compared with studies in wandoo woodlands, the results of the present study indicate that the conservation of ground-layer habitat is likely to be of less importance in the jarrah forest. These habitat differences indicate that site-specific information is critical if the management and conservation of individual species is to be effective.

[Truncated abstract] Mediterranean southwest Australia, a global biodiversity hotspot, has nutrient deficient soils, exacting climatic conditions and is species rich with 7380 native vascular plant species, of which 49% are endemic. The region is expected to experience one of the world's highest degrees of biodiversity loss and change in the coming decades, with introduced species presenting a major threat. Limited knowledge is available on the mechanisms of ecosystem change associated with invasion and fire in this biodiversity hotspot region. Banksia woodland, an iconic complex species-rich natural ecosystem is one of the major vegetation types of the coastal sandplain, extending from 15 to 90 km inland and 400 kms along the west coast. The following hypothesis was tested to explore the ecological impacts of invasion: Is invasion of Banksia woodland by the introduced species Ehrharta calycina and Pelargonium capitatum accompanied by an alteration in ecosystem properties and processes, whereby the degree of change is related to fire frequency and abundance of introduced species? Different vegetation conditions, i.e. Good Condition (GC), Medium Condition (MC), Poor Condition invaded by Ehrharta calycina (PCe) and Poor Condition invaded by Pelargonium capitatum (PCp) were utilized for field assessments. ... In the soil seed bank, species numbers and germinant density decreased significantly for native and seeder (fire sensitive) species between GC sites and invaded sites. Surprisingly 52% of germinants at GC sites were from introduced species, with much of the introduced soil seed bank being persistent. Native species were dominated by perennial shrubs, herbs and sedges, while introduced species were dominated by perennial and annual grasses and herbs. Invasion by introduced species, associated with frequency of fire, altered the ecosystem, thus disadvantaging native species and improving conditions for even greater invasion within the Banksia woodland. Significantly higher soil phosphorus P (total) and P (HCO3) were found at PCe and PCp sites compared to GC sites. Leaf nutrient concentrations of phosphorus were significantly higher, and potassium and copper significantly lower in PCe and PCp sites, with introduced species having significantly greater concentrations than native species (except Manganese). This study demonstrated the key role of phosphorus in the Banksia woodland, in contrast to other research which identified nitrogen as the major nutrient affected by invasion. Higher levels of soil and leaf phosphorus, loss of species diversity and function, changes in fire ecology and canopy cover and a limited native soil seed bank make restoration of a structural and functional Banksia woodland from the soil seed bank alone unlikely. Without management intervention, continuing future fire is likely to result in a transition of vegetation states from GC to MC and MC to PC. The knowledge gained from this study provides a better ecological understanding of the invasive process. This enhanced understanding will enable the development of adaptive management strategies to improve conservation practices within a biodiversity hotspot and reduce the impact of the key threatening process of invasion.