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1
Kew, G. A., R. J. Gilkes und D. Evans. „Relationships between fabric, water retention, and strength of hard subsoils in the south of Western Australia“. Soil Research 48, Nr. 2 (2010): 167. http://dx.doi.org/10.1071/sr09080.
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Crop yield in the sandy soils of the Western Australian wheatbelt is influenced strongly by the plant-available water (PAW) and strength of subsoils. The fabric of hard subsoils of fluvial and aeolian origin has been compared with that of in situ saprolite materials that also occur as subsoils in Western Australia. A fabric classification was developed and relationships between, fabric, water retention, and strength were examined. The clay matrix of hard subsoils is denser and is less porous than in saprolite. Hard subsoils contain rounded quartz grains and transported, rounded aggregates of clay (spherites), while saprolite contains angular quartz grains in a more porous isotropic kaolin clay matrix developed by in situ weathering. At all matric potentials there were large differences in water retention between hard subsoils and saprolite. The dry and wet strengths of subsoils are lower than for saprolite but the strength of both materials is similarly affected by changes in water content and matric potential. A variety of factors including the size, shape, degree of sorting of quartz grains, distribution of dense clay matrix, and cementing by iron oxides or amorphous silica affect the strength of subsoils. The fabric classification is predictive of water retention and strength.
2
Coates, Fiona, und J. B. Kirkpatrick. „Is Geographic Range Correlated with Climatic Range in Australian Spyridium Taxa?“ Australian Journal of Botany 47, Nr. 5 (1999): 755. http://dx.doi.org/10.1071/bt97066.
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The major centres of local endemism and richness at the species level and below in Spyridium Fenzl are located on the southern coast of Western Australia and in south-eastern South Australia. There are only a few Spyridium taxa with ranges that transgress the boundaries of the following four regions: south- western Western Australia; south-eastern South Australia and western Victoria; eastern Victoria, New South Wales and southern Queensland; Tasmania. Synthetic climatic variables were generated for all recorded populations of Spyridium taxa. Variabilities in these were related to the maximum geographic ranges of taxa in Australia as a whole, and within the regions, in order to test the hypothesis that narrow endemism is explained by climatic restriction since the last glacial. In Australia as a whole, local endemics are both narrowly and widely distributed climatically, as are more widespread Spyridiumtaxa, and there were no significant relationships between the climatic and geographic ranges of taxa confined to the Australian mainland regions. However, Tasmanian taxa exhibited a strong positive relationship. Restriction of range as a result of climate change is an unlikely explanation for local endemism in Spyridium in mainland Australia, where topographic and climatic gradients are generally subdued, and which apparently experienced less severe climatic oscillations during the Quaternary. However, this hypothesis cannot be rejected for Tasmania, which experienced more extreme Quaternary climatic fluctuations than the present-day areas of mediterranean climate, and hence more severe fluctuations in the area and location of climatically suitable habitats.
3
TINERELLA, PAUL P. „Taxonomic revision and systematics of continental Australian pygmy water boatmen (Hemiptera: Heteroptera: Corixoidea: Micronectidae)“. Zootaxa 3623, Nr. 1 (11.03.2013): 1–121. http://dx.doi.org/10.11646/zootaxa.3623.1.1.
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The pygmy water boatmen (Hemiptera: Heteroptera: Micronectidae) of continental Australiaare revised. The two genera and 17 species occurring in Australiaare fully described and keyed. The following species are transferred to Austronecta gen. nov.: Micronecta australiensis Chen, M. micra Kirklady, and M. carinata Chen. Austronecta bartzarum, sp. nov., is newly described. Within Micronecta Kirkaldy, thirteen species are recorded, including M. paragoga sp. nov. The following new synonymies are proposed: Micronecta illiesi Wróblewski, Micronecta concordia King and Micronecta dixonia King are junior synonyms of Micronecta annae Kirkaldy. A lectotype is designated for Micronecta tasmanica Wróblewski. Micronecta ludibunda Breddin is newly recorded for Australia, based on one male examined from Queensland. Within Australia, range extensions are recorded for the following species: Austronecta australiensis (New South Wales, Queensland); A. micra (Western Australia); Micronecta lansburyi Wróblewski (Western Australia); M. adelaidae Chen (Western Australia); M. major Chen (Queensland); M. halei Chen (South Australia); M. virgata Hale (Northern Territory); M. quadristrigata Breddin (Northern Territory); and M. queenslandica Chen (Northern Territory). All species are described and illustrated. Discussion and documentation of all primary type material is provided and where available, type specimens are illustrated. All male genitalic structures are illustrated with scanning electron micrographs. Line drawings are included for all other diagnostic characters, along with color habitus illustrations for both sexes of all species. Distribution maps are included for the following species: Austronecta micra, A. bartzarum, Micronecta paragoga, M. lansburyi, M. adelaidae, M. major, M. virgata, M. halei, M. quadrstrigata, and M. queenslandica. Diagnostic morphology and variation is discussed for all treated species. A phylogenetic analysis of Australasian micronectid generic relationships is presented. Discussion is provided on zoogeographic relationships of Australian Micronectidae.
4
Tibby, J., und D. Tiller. „Climate–water quality relationships in three Western Victorian (Australia) lakes 1984–2000“. Hydrobiologia 591, Nr. 1 (Oktober 2007): 219–34. http://dx.doi.org/10.1007/s10750-007-0804-5.
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MACFARLANE, TERRY D., GALINA V. DEGTJAREVA, TAHIR H. SAMIGULLIN, CARMEN M. VALIEJO-ROMAN, CONSTANTIN I. FOMICHEV und DMITRY D. SOKOLOFF. „Althenia tzvelevii (Potamogetonaceae), a new species from SW Western Australia with bilocular anthers: morphology and molecular phylogenetic relationships“. Phytotaxa 471, Nr. 3 (17.11.2020): 193–207. http://dx.doi.org/10.11646/phytotaxa.471.3.2.
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A new species Althenia tzvelevii is described from south western Australia. This is the second species after A. bilocularis described with bilocular anthers. Illustrations of plant morphology are provided by means of SEM images and habitat photographs are included. The phylogenetic relationships of the new species were investigated using five plastid DNA markers (matK, ndhF, rbcL, rpoB, and rpoC1), with published sequences augmented by several new sequences resulting in coverage of all described species in the genus. Althenia tzvelevii forms a clade with A. patentifolia and A. bilocularis and other relationships within the genus are clarified. The Western Australian Althenia hearnii is strongly supported as sister to the Eurasian-African clade composed by A. filiformis and A. orientalis.
6
Tindale, MD, und LA Craven. „Three new species of Glycine (Fabaceae: Phaseolae) from north-western Australia, with notes on amphicarpy in the genus“. Australian Systematic Botany 1, Nr. 4 (1988): 399. http://dx.doi.org/10.1071/sb9880399.
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Three new species of Glycine Willd., viz. G. albicans, G. Lactovirens and G. hirticaulis from north-western Australia are described and illustrated. Their putative relationships are presented. A key is provided to the species of Glycine in north-western Australia. Two forms of amphicarpy occur within the genus Glycine.
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Perrie, Leon R., Daniel J. Ohlsen, Lara D. Shepherd, Michael Garrett, Patrick J. Brownsey und Michael J. Bayly. „Tasmanian and Victorian populations of the fern Asplenium hookerianum result from independent dispersals from New Zealand“. Australian Systematic Botany 23, Nr. 6 (2010): 387. http://dx.doi.org/10.1071/sb10028.
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The fern Asplenium hookerianum Colenso (Aspleniaceae) is indigenous to New Zealand and Australia. In New Zealand, it is widespread and genetically diverse, with 26 haplotypes previously identified for the chloroplast trnL–trnF locus. In Australia, A. hookerianum is currently known only from two small populations in Victoria and two in Tasmania. The present study assessed the diversity, relationships and biogeographic history of the Australian populations. A single trnL–trnF haplotype was identified in Tasmanian populations, and it was shared with populations in south-western New Zealand. The single haplotype found in Victorian populations was unique and most similar to a haplotype found in populations from central and eastern North Island, New Zealand. Relationships among haplotypes suggest that the two Australian haplotypes are derived within the group (not close to the root of the haplotype network) and only distantly related. This pattern is consistent with two independent dispersals of A. hookerianum from New Zealand to Australia. These findings are unique in providing evidence for more than one trans-Tasman dispersal event in a species of vascular plant.
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Itzstein-Davey, Freea. „The representation of Proteaceae in modern pollen rain in species-rich vegetation communities in south-western Australia“. Australian Journal of Botany 51, Nr. 2 (2003): 135. http://dx.doi.org/10.1071/bt02048.
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The Proteaceae family is a large Gondwanan plant family with a major centre of richness in south-western Australia. Modern pollen–vegetation relationships in the two areas of species richness in the northern and southern sandplains of south-western Australia were investigated to calibrate fossil-pollen studies concurrently conducted on Eocene, Pliocene and Quaternary sediment. Results indicated that the Proteaceae component in modern pollen rain can be quite high, contributing up to 50% of the count. Some sites showed a dominant type (such as Banksia–Dryandra), whilst others had up to six different genera represented. Exactly how and when the biodiversity of Proteaceae in south-western Australia developed is unknown. This work provides a benchmark for comparisons with studied fossil material to unravel patterns of diversity of this family in south-western Australia.
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Moller, Andersen N. „Cladistic biogeography of marine water striders (Insecta, Hemiptera) in the Indo-Pacific“. Australian Systematic Botany 4, Nr. 1 (1991): 151. http://dx.doi.org/10.1071/sb9910151.
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More than 120 species of marine water striders (Hemiptera, Gerromorpha), representing three families and eight genera, are distributed throughout the lndo-Pacific region. They live in marine habitats such as mangroves, intertidal coral reef flats and the sea surface near coral and rocky coasts. Five species of sea skaters, Halobates (Gerridae), have colonised the surface of the open ocean. Adult marine water striders are wingless but may disperse along coasts, chains of islands and possibly across wider stretches of open sea. Although some species of coral bugs, Halovelia (Veliidae) and Halobates are widespread, most species of marine water striders have rather restricted distributions. Cladistic hypotheses are now available for the genera Halovelia, Xenobates (Veliidae) and Halobates. Based upon distributional data for about 110 species, a number of areas of endemism can be delimited within the Indo-Pacific region. The results of component analyses of taxon-area cladograms for several monophyletic species-groups of marine water striders are presented. The faunas of northern New Guinea, the Bismarck and Solomon Islands (Papuasia) are closely related and show much greater affinity with Maluku, Sulawesi and the Philippines than with the fauna of northern Australia. Relationships between the faunas of Papuasia + Sulawesi + the Philippines and those of Borneo + Jawa + Malaya are relatively weak. Marine water striders endemic to islands of the western Pacific show relationships among themselves and with Australia. Most marine water striders from the Indian Ocean (East Africa, Madagascar, Mauritius, Seychelles and Maldives) can be derived from the Indian-South-east Asian fauna. Composite faunas of marine water striders (either of different age or origin) are found in New Guinea, New Caledonia, Fiji Islands, the Philippines, tropical Australia and East Africa. The biogeography of marine water striders does not support the traditional division of the Indo- Pacific into the Ethiopian, Oriental and Australian regions. The distributional patterns are more compatible with a set of hierarchical relationships between more restricted areas of endemism.
10
Merritt, D. J., D. H. Touchell, T. Senaratna, K. W. Dixon und K. Sivasithamparam. „Water sorption characteristics of seeds of four Western Australian species“. Australian Journal of Botany 51, Nr. 1 (2003): 85. http://dx.doi.org/10.1071/bt02040.
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The relationship between storage temperature, relative humidity and seed water content was investigated for four species native to Western Australia: Acacia bivenosa DC., Anigozanthos manglesii D.Don., Banksia ashbyi E.G.Baker and Mesomelaena tetragona (R.Br.) Benth. Water sorption isotherms were constructed at 5, 23 and 50�C and the enthalpy of water sorption was calculated by van�t Hoff analysis. Seeds of three species, A. manglesii, B.�ashbyi and M. tetragona, showed a sigmoidal relationship between seed water content and relative humidity. Intact seeds of Acacia bivenosa maintained a constant water content at temperatures of 23�C or less due to the impermeable seed coat; however, isotherms of scarified seeds were similar in shape to those of the other species at all temperatures. The enthalpy of water sorption ranged from –19 kJ mol–1 for M. tetragona seeds to –29 kJ mol–1 for B. ashbyi seeds and was dependent on water content. However, all species had a maximum sorption strength at 2–6% water content and three regions of water-binding strength were evident. Each of these species has water sorption characteristics consistent with orthodox storage behaviour and the results of this study provide a framework for improving seed storage methods for the highly diverse Western Australian flora.
11
Rawlings, Lesley H., David Barker und Stephen C. Donnellan. „Phylogenetic relationships of the Australo-Papuan Liasis pythons (Reptilia : Macrostomata), based on mitochondrial DNA“. Australian Journal of Zoology 52, Nr. 2 (2004): 215. http://dx.doi.org/10.1071/zo03030.
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The genus Liasis comprises two groups of pythons, the olive python, Liasis olivaceus, and the water pythons L. fuscus and L. mackloti. We used partial mitochondrial control region DNA sequences to examine (a) the phylogeography of water pythons from five Indonesian Lesser Sunda islands, New Guinea, and northern Australia, (b) the relationships of the two subspecies of olive pythons, and (c) the relationship of the Papuan python, Apodora papuana, with the species of Liasis. Maximum likelihood, parsimony and distance analyses showed that A. papuana is the sister lineage to all Liasis and that Liasis fuscus/L. mackloti and L. olivaceus are separate lineages. There is also support for the reciprocal monophyly of the two olive python subspecies, L. olivaceus barroni and L. o. olivaceus, and for distinction of island populations described previously as L. mackloti dunni from Wetar and L. mackloti savuensis from Sawu. These two island populations are as equally distinct as the populations from the island cluster of Babar/Semau/Timor. There is strong support for the recognition of two lineages ('eastern' and 'western') of water pythons in Australia. We propose that the drier interior of the Plio-Pleistocene land bridge between Australia and New Guinea acted as a barrier to gene flow, influencing the genetic divergence between the 'eastern' and 'western' lineages of the semi-aquatic water pythons.
12
Wong, M. T. F., R. J. Corner und S. E. Cook. „A decision support system for mapping the site-specific potassium requirement of wheat in the field“. Australian Journal of Experimental Agriculture 41, Nr. 5 (2001): 655. http://dx.doi.org/10.1071/ea00191.
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The intensely weathered nature of Western Australian cropping soils and the long history of potassium depletion by the farming system has resulted in increased incidence of potassium deficiency in wheat. There is currently no scientifically based method for potassium recommendation in Western Australia. This paper describes the use of site-specific plot-scale field trials carried out in 1995–98 and a crop response model to develop a generally applicable potassium recommendation system. Geographic information system technology was used to extend the uniform potassium recommendation system into a system for mapping spatially variable potassium requirement that takes account of crop demand and soil available potassium. The field trials were carried out on a range of soil types and showed that wheat response to potassium can be described by the Mitscherlich equation. The size of the response was dependent on the soil test value for plant available potassium and the yield of the crop. The latter is mainly dependent on rainfall in the water-limited Mediterranean environment of Western Australia. The relationships between the maximum achievable yield, crop response and soil available potassium values were quantified in order to allow the decision support system to be developed for uniform whole-paddock fertiliser recommendation. Both soil available potassium and yield are very spatially variable in Western Australia and for wheat, the coefficient of variation of yield within the paddock is often of the order of 30%. Soil property variation can be of a similar order. Maps of soil available potassium values and of spatially variable target yield determined either from (i) farmer’s estimate, (ii) yield monitors and (iii) remotely sensed normalised difference vegetation index measurements allow this decision system to map spatially variable potassium requirement. Comparison of the map of potassium requirement with measured spatially variable response to potassium showed that the decision support system performed satisfactorily.
13
Stephens, D. J., und T. J. Lyons. „Rainfall-yield relationships across the Australian wheatbelt“. Australian Journal of Agricultural Research 49, Nr. 2 (1998): 211. http://dx.doi.org/10.1071/a96139.
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A network of rainfall stations was selected across the Australian wheatbelt and monthly rainfall regressed with wheat yields from the surrounding shires for the period 1976-87. Yields were found to be strongly related to fluctuations in total rainfall amount and the seasonal distribution of rainfall through the year. These temporal relationships vary spatially and appear to be regulated by the water-holding capacity of regional soils. Sixteen agrometeorological zones were defined with similar rainfall-yield relationships. In all these, autumn rains that permit an early sowing, and finishing rains after July, are most important for higher yields. As the rainfall distribution becomes more winter-dominant, both crop yield variability and the usefulness of high winter rainfall decreases. Heavy rainfall in the month after sowing can have a negative effect in southern Australia, as plants are more prone to suffer potential yield losses from a wet soil profile. Waterlogging has a large negative effect in the south-west of Western Australia, such that the rainfall distribution can be more important than the rainfall amount. Rainfall-yield correlations are generally more positive in drier regions, and are enhanced by persistent rainfall anomalies between April and November during El Niño Southern Oscillation years.
14
Pate, J. S., W. H. Verboom und P. D. Galloway. „Co-occurrence of Proteaceae, laterite and related oligotrophic soils: coincidental associations or causative inter-relationships?“ Australian Journal of Botany 49, Nr. 5 (2001): 529. http://dx.doi.org/10.1071/bt00086.
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This communication presents the hypothesis that certain Australian lateritic and related oligotrophic soils may have been partly derived biotically from soluble iron-rich complexes generated following secretion of low-molecular weight organic acids by phosphate-absorbing specialised proteoid (cluster) roots of proteaceous plants. Subsequent precipitation of the iron is then pictured as occurring onto the oxide rinds of developing laterite after consumption of the organic components of the complexes by soil bacteria. The hypothesis is f irst examined in relation to current theories of origins of laterites and the extent of the coincidences worldwide in past and present times between Proteaceae and oligotrophic soil types of lateritic character. The paper then provides more definitive lines of evidence supporting the hypothesis, based largely on recent studies by the authors in south-western Western Australia. This relates to (a) cases of definitive association in habitats rich in Proteaceae between zones of root proliferation and ferricrete layers in lateritic soils, (b) proximity in soil profiles between ferric deposits and current and ancestral root channels, (c) the recovery of citrate-consuming bacteria from soil profiles and specifically from ferricrete rinds and horizons accumulating sesquioxide organic matter and (d) distribution of iron and phosphorus within plant and soil profile components consistent with ferricrete rinds being generated by rhizosphere-mediated interactions of plants and microbes under conditions of severely limited availability of phosphorus. The mode of functioning of proteoid root clusters is then discussed, especially in relation to exudation of organic acid anions, uptake of phosphorus and the subsequent fate of organic anions and their metal ion complexes in the system. An empirically based scheme is presented indicating flow profiles for phosphorus and iron between soil, ferricrete rinds and bacterial and plant components. We then discuss possible carbon costs to proteaceous plant partners when accessing phosphorus under the nutrient-impoverished conditions typical of heathlands and open woodlands of Mediterranean-type ecosystems of Western Australia. The paper concludes with a critical overview of the hypothesis, particularly its implications regarding possible higher plant: microbial influences shaping soil and landscape evolution in the regions involved.
15
Norman, MD. „Ameloctopus litoralis, gen. et sp. nov. (Cephalopoda : Octopodidae), a new shallow-water octopus from tropical Australian waters“. Invertebrate Systematics 6, Nr. 3 (1992): 567. http://dx.doi.org/10.1071/it9920567.
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A new genus of octopus is described from northern Australian waters. Ameloctopus litoralis, gen. et sp. nov., is a shallow-water octopus characterised by the absence of an ink sac, vestigial funnel organ, terminal organ without a diverticulum, marked elongation of the arms and arm autotomy. It is found across northern Australia from southern Queensland to north-west Western Australia, primarily on coastal mudflats and intertidal reefs. This species occupies lairs in shallow and intertidal coastal habitats, feeding by extending arms from the safety of the lair or by foraging at night during low tides, over open sand, mud and rubble. A. litoralis lays large eggs, indicating that hatchlings are benthic and dispersal limited. Loss of the ink sac in a shallow-water octopod and the development of arm autotomy are discussed. Relationships with other octopod taxa exhibiting similar traits are examined.
16
Young, Diana. „Water as Country on the Pitjantjatjara Yankunytjatjara Lands South Australia“. Worldviews: Global Religions, Culture, and Ecology 10, Nr. 2 (2006): 239–58. http://dx.doi.org/10.1163/156853506777965839.
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AbstractAnangu, Pitjantjatjara and Yankunytjatjara people living in the north-western areas of South Australia conceptualize changes in the surface of land as evincing the presence of ancestral power. Rain is one such catalyst of change, though it is by no means a certainty on the Pitjantjatjara Yankunytjatjara Lands. When it does appear, water does not stay long on the surface: it is shimmering and unstable. This paper examines the nature of various water sources in contemporary indigenous life, the spatial relationships between earth and sky and the dialectic between life and death that they mediate.
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Wong, M. T. F., und R. J. Harper. „Use of on-ground gamma-ray spectrometry to measure plant-available potassium and other topsoil attributes“. Soil Research 37, Nr. 2 (1999): 267. http://dx.doi.org/10.1071/s98038.
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The incidence of potassium (K) deficiency is increasing in crops, pastures, and forestry in south-western Australia. Although soil K can be measured using soil sampling and analysis, γ-ray spectrometry offers a potentially cheaper and spatially more precise alternative. This could be particularly useful in precision agriculture, where inputs are applied according to need rather than by general prescription. In a study of topsoils near Jerramungup, Western Australia, strong relationships (r2 = 0·9) were found between on-ground counts of γ-rays derived from 40K (γ-K) and both total K and plant-available K. The success of γ-ray spectrometry in predicting available K relied on a strong relationship (r2 = 0·9) between total K and available K which may not hold in all areas. Although the relationship between γ-K and available K held over the range of 36–1012 mg/kg, crop response to K fertilisers is only expected when the available K content is <100 mg/kg. Estimates of available K from γ-K were unreliable at this lower end of the regression curve. Separate analysis with a subset of the data with available K <100 mg/kg showed a poor relationship between γ-K and available K (r2 = 0·05; d.f. 11). The usefulness of γ-ray spectrometry may therefore be restricted to defining areas where response to fertiliser K may occur, and where further soil sampling and analysis are required to predict the fertiliser requirement. Strong relationships (r2 = 0·9) were also found between γ-K and a range of other soil attributes, including clay, silt, and organic carbon content. These relationships depended on the locally strong relationship between total K and these soil attributes. Since such relationships do not hold everywhere, the utility of γ-ray spectrometry will likewise be limited. Site-specific calibrations are required if γ-ray spectrometry is to be used for soil property mapping.
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Powell, Jocelyn M., David A. Morrison, Paul A. Gadek, Darren M. Crayn und Christopher J. Quinn. „Relationships and Generic Concepts within Styphelieae (Epacridaceae)“. Australian Systematic Botany 10, Nr. 1 (1997): 15. http://dx.doi.org/10.1071/sb95044.
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A morphological data base of 30 characters has been assembled for 33 terminal taxa in the tribe Styphelieae sensu Powell et al. (1996), as well as four outgroup taxa representing the other major affinity groups previously identified within the Epacridaceae on morphological and molecular data. Heuristic and bootstrap analyses provided strong support for the tribe, but indicated a need to modify several long-established generic concepts. Four genera are shown here to be polyphyletic. Six new monotypic genera should be segregated from Astroloma. Brachyloma should be divided into three segregates. Two distinct affinity groups warranting generic status were identified within Cyathodes. The separation of the monotypic Western Australian genus, Croninia, from Leucopogon s.l. is supported, and four other separate entities are here recognised: four species from section Heteranthus Benth. should be united with Lissanthe, and the other three segregates warrant generic status. In addition, Monotoca is paraphyletic, and should be redefined to incorporate Oligarrhena, while a new genus, ‘Pseudactinia’, is required to accommodate two new species from Western Australia. There seems little justification for maintaining the distinction between Trochocarpa and Decatoca. The pattern of intergeneric relationships resolved suggests that Astroloma s.l., Coleanthera, Conostephium, Croninia, Melichrus, Styphelia and much of Leucopogon s.l. constitute an affinity group, and that Brachyloma s. str. and B. scortechinii are basal within the tribe, but there is only weak support for these aspects of the topology within the data.
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McKissock, I., R. J. Gilkes, R. J. Harper und D. J. Carter. „Relationships of water repellency to soil properties for different spatial scales of study“. Soil Research 36, Nr. 3 (1998): 495. http://dx.doi.org/10.1071/s97071.
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In order to predict the occurrence of water repellency, which is a labile property, from field survey data obtained throughout the year, it is necessary to identify predictive relationships between water repellency and commonly measured soil properties. This paper evaluates these relationships for diverse soil assemblages. These soil assemblages include a set of reference soils from the south-west of Western Australia (an area of 250 000 km2), more intensively sampled suites of soils in several smaller soil{landscape associations within the south-west of Western Australia (≅1000 km2), soils from single farms (1-10 km2) and transects (≅0·001 km2), and single soil profiles (≅m2). The severity of water repellency was assessed by measuring water drop penetration time in seconds (WDPT) and was related to intrinsic properties of soils using log-transformed data. For the set of soils from the West Midland Sandplain the type of land use was also considered as a variable. There is a general tendency for WDPT to increase as organic matter content increases and decrease as the content of fine mineral material increases (clay, silt, very fine sand). However, there is no single soil property that is able to predict WDPT adequately. Furthermore, reliability of prediction decreases as the area of sampling increases. There appear to be no systematic differences in the capacity of organic matter from pasture or crop to induce water repellency, but increments of organic matter under bush increase water repellency at a greater rate than does organic matter from crop or pasture.
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Kaur, Parwinder, Krishnapillai Sivasithamparam und Martin J. Barbetti. „Host Range and Phylogenetic Relationships of Albugo candida from Cruciferous Hosts in Western Australia, with Special Reference to Brassica juncea“. Plant Disease 95, Nr. 6 (Juni 2011): 712–18. http://dx.doi.org/10.1094/pdis-10-10-0765.
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White rust, caused by Albugo candida, is a serious pathogen of Brassica juncea (Indian mustard) worldwide and poses a potential hazard to the presently developing canola-quality B. juncea industry in Australia. Nine isolates of A. candida, representing strains collected from B. juncea, B. rapa, B. oleracea, B. tournefortii, Raphanus raphanistrum, R. sativa, Eruca vesicaria subsp. sativa, Capsella bursa-pastoris and Sisymbrium irio, from different locations in Western Australia (W.A.), were tested on cruciferous host differentials to characterize their pathogenicity. In particular, these studies were aimed to determine the hazard to the newly emerging B. juncea industry in Australia from races or pathotypes of A. candida present. Pathogenicity tests with appropriate differentials demonstrated the presence in W.A. of a unique strain from B. rapa that did not show characteristics of either race 7A or 7V and clearly is a distinct new pathogenic strain within race 7. Different strains collected from W.A. differed in their host range, with the strains from B. tournefortii and S. irio being highly host specific, failing to be pathogenic on any other differentials. B. tournefortii was host to a strain attacking B. juncea and E. vesicaria subsp. sativa. The strain from R. raphanistrum showed a relatively wide host range among the differentials tested. B. tournefortii, C. bursa-pastoris, R. raphanistrum, and S. irio are common weeds within grain belt and horticultural regions in Australia. The B. oleracea isolate (race 9) was pathogenic to B. juncea ‘Vulcan’ whereas the isolate from B. juncea (race 2V) was not pathogenic on B. oleracea. Similarly, the strain from C. bursa pastoris (race 4) was pathogenic on B. juncea Vulcan but the B. juncea strain was not pathogenic on C. bursa pastoris. In contrast, the strain from R. sativus (race 1) was pathogenic on B. juncea and the B. juncea strain was also pathogenic on R. sativus. Field isolates from B. rapa, B. tournefortii, E. vesicaria subsp. sativa, and S. irio were all nonpathogenic on B. juncea. Isolates from B. juncea and R. raphanistrum were pathogenic on B. napus (FAN 189). For the nine A. candida isolates from W.A., complete rDNA internal transcribed spacer region nucleotide sequence analysis showed a nucleotide identity range of 72.4 to 100% in comparison with previous Australian collections of A. candida and those previously reported in Europe and Asia. The B. tournefortii isolate of A. candida from W.A. formed a distinct clade on its own, with an identity range of 77.4 to 80.5% compared with the other isolates. Isolates from R. raphanistrum and R. sativus from W.A. were least similar to the other isolates, with a nucleotide identity similarity of only 72.4%. Characterization of the races of A. candida in Western Australia adds to the current knowledge regarding the diversity of this pathogen, allows choice of Brassica spp. or cultivars with resistance to races across different regions, and highlights the particular cruciferous weeds involved in pathogen inoculum carryover between successive cruciferous crops, particularly B. juncea crops.
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McLaughlin, M. J., N. A. Maier, R. L.Correll, M. K. Smart, L. A. Sparrow und A. McKay. „Prediction of cadmium concentrations in potato tubers (Solanum tuberosum L.) by pre-plant soil and irrigation water analyses“. Soil Research 37, Nr. 1 (1999): 191. http://dx.doi.org/10.1071/s98031.
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Potato tubers can accumulate high concentrations of cadmium (Cd) in edible portions, so that techniques to determine high risk Cd environments are required by growers. The use of combined soil and irrigation water analyses prior to crop planting was investigated as a means to predict risks of Cd accumulation in tubers. Soils and irrigation waters were analysed at 134 sites in the major potato production areas in Western Australia, South Australia, Tasmania, Victoria, and New South Wales. Irrigation waters were analysed for electrical conductivity (EC), major cations, and anions. Cadmium was extracted from soil using aqua regia (1 : 3 HNO3: HCl), EDTA (ethylenediamine-N,N,N′,N′-tetraacetate), DTPA (diethylene-triamine-pentaacetate), 0·01 M CaCl2, 0·01 M Ca(NO3)2, 0·1 M CaCl2, and 1·0 M NH4NO3. The preferred test procedure was validated in a subsequent sampling and analysis program at 39 sites. Irrigation water quality (EC or Cl concentration), measured prior to planting, explained the greatest variation in tuber Cd concentrations. Of the soil test procedures, only Cd extracted by 0·01 M CaCl2 significantly improved the predictive capacity of water EC. These 2 measures explained >55% of the variance in tuber Cd concentrations. The data set were transformed to generate a probability curve for exceeding Cd concentrations of either 0·05 or 0·1 mg/kg fresh weight, the latter being the current maximum permitted concentration (MPC) in Australia for potato tubers. The probability of producing potato tubers exceeding 0·05 and 0·1 mg/kg fresh weight was >50% once irrigation water EC increased above 1·4 and 3·0 dS/m, respectively. Using the relationships developed, growers should be able to quantify Cd risks by a simple test of irrigation water EC prior to planting and, if further precision is needed, also determine CaCl2-extractable Cd in soil.
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Franklin, Donald C., und Richard A. Noske. „Nectar sources used by birds in monsoonal north-western Australia: a regional survey“. Australian Journal of Botany 48, Nr. 4 (2000): 461. http://dx.doi.org/10.1071/bt98089.
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We document the flora that provides nectar for birds in monsoonal north-western Australia, and examine the relationship between floral morphology and bird morphology in the region. Twenty-four regular nectarivores (21 honeyeaters, two lorikeets, one white-eye) and 29 opportunist species have been observed probing the flowers of 116 species of plants from 28 families. Amongst the nectar sources, the Myrtaceae is dominant in both the number of species and frequency of use, followed distantly by the Proteaceae and Loranthaceae. Variation between bird species in patterns of use of different floral structures primarily reflected the habitats occupied rather than shared or co-evolved morphology. Woodland birds made particular use of staminiferous cups, mangal specialists particular use of open sepaliferous and petaliferous flowers, and forest specialists and habitat generalists intermediate use of these flower types. Bird–flower relationships in monsoonal Australia may be generalised because of a combination of the dominance of mass-flowering myrtaceous trees, aridity during past glacials that may have eliminated specialists from the system, and perhaps also because many nectar sources are shared with bats.
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Braaten, Christine C., P. Brandon Matheny, Debra L. Viess, Michael G. Wood, Joseph H. Williams und Neale L. Bougher. „Two new species of Inocybe from Australia and North America that include novel secotioid forms“. Botany 92, Nr. 1 (Januar 2014): 9–22. http://dx.doi.org/10.1139/cjb-2013-0195.
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The secotioid form of fruit bodies of mushroom-forming fungi may be an intermediate evolutionary modification of epigeous agaricoid or pileate–stipitate forms (i.e., with pileus, spore-bearing tissues, and stipe) and typically hypogeous, gasteroid- or truffle-forming species, in which the fruit bodies have been reduced to enclosed structures containing modified spore-producing tissues. To date, only a single secotioid species (Auritella geoaustralis Matheny & Bougher ex Matheny & Bougher) has been described in the ectomycorrhizal family Inocybaceae, a hyperdiverse clade of ca. 500–700 species with a cosmopolitan distribution. Fieldwork in Australia and western North America, however, has revealed two novel secotioid forms of Inocybe (Fr.) Fr., the first to be formally described in the genus. In this investigation, we analyze their phylogenetic relationships using molecular sequence data from multiple unlinked loci to test whether these are environmental variants of agaricoid forms or represent independent lineages. Results of phylogenetic analyses suggest these fungi have converged to the secotioid form independently. However, the California secotioid taxon (Inocybe multifolia f. cryptophylla f. nov.) is a phenotypic variant of the newly described agaricoid taxon (Inocybe multifolia sp. nov.). Similarly, the Australian secotioid form (Inocybe bicornis f. secotioides f. nov.) is nested within a clade of otherwise agaricoid forms of a second novel species (Inocybe bicornis sp. nov.) described from southwest Western Australia. Overall, four species with sequestrate forms within Inocybaceae can now be recognized, three of which are distributed in Australia and one in western North America, in the genera Auritella and Inocybe.
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Garkaklis, Mark J., J. S. Bradley und R. D. Wooller. „The relationship between animal foraging and nutrient patchiness in south-west Australian woodland soils“. Soil Research 41, Nr. 4 (2003): 665. http://dx.doi.org/10.1071/sr02109.
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The woylie (Bettongia penicillata) was once common and abundant over the southern third of the Australian continent. Since European settlement the range of this rat-kangaroo has become reduced by more than 97%, and until the early 1990s, only 3 small natural populations remained, all in south-western Australia. These medium-sized (c. 1 kg) marsupials create a large number of diggings as they forage for the hypogeous fruiting bodies of ectomycorrhizal fungi upon which they feed. The effect of such foraging activity on the availability of plant nutrients in the vicinity of such diggings was evaluated in simulated digging experiments. Available nitrate, ammonium, and sulfur decreased significantly 3 years after diggings were constructed and had filled in, whereas phosphorus, potassium, iron, and organic carbon remained unchanged. The results suggest that preferential water infiltration via woylie diggings leads to a decrease in those soil nutrients that are susceptible to leaching and indicates that digging vertebrates may influence the distribution of surface soil nutrients.
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Zhang, Heping, Neil C. Turner, Narelle Simpson und Michael L. Poole. „Growing-season rainfall, ear number and the water-limited potential yield of wheat in south-western Australia“. Crop and Pasture Science 61, Nr. 4 (2010): 296. http://dx.doi.org/10.1071/cp09288.
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Knowledge of the contribution of ear number per unit area, grains per ear, and kernel weight to grain yield is important in understanding the limits to the water-limited potential yield of wheat in rain-fed agricultural regions. This paper analyses the relationships between grain yield, yield components and growing-season rainfall using data from the low-, medium-, and high-rainfall zones of the cropping region of south-western Australia. The aim of the paper is to quantify the contribution of ear number, grains per ear and kernel weight to grain yield and define the yield components of wheat required to achieve its water-limited yield. The grain yield of wheat was closely related to the number of grains per unit area (r2 = 0.90) and ears/m2 (r2 = 0.75), but poorly correlated with kernel weight (r2 = 0.30) and grains/ear (r2 = 0.09). The number of grains per unit area was highly related (r2 = 0.75) to the number of ears per unit area across the rainfall zones of the cropping region, and strongly correlated (r2 = 0.88–0.94) to the spike dry weight at anthesis. The highest yields achieved in the field were close to the water-limited potential estimated using the French and Schultz method. To achieve this water-limited potential, wheat requires 1 ear per m2 for every mm of growing-season rainfall (r2 = 0.92). We conclude that the number of ears per unit area is the most important factor required in order to achieve high yields of up to a yield of 6 t/ha in wheat in rain-fed south-western Australia.
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Butcher, Ryonen. „New taxa of 'leafless' Tetratheca (Elaeocarpaceae, formerly Tremandraceae) from Western Australia.“ Australian Systematic Botany 20, Nr. 2 (2007): 139. http://dx.doi.org/10.1071/sb06015.
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The relationships among rare ‘leafless’ species of Tetratheca Sm. occurring on banded ironstone ranges near Koolyanobbing, Western Australia, and allied, unclassified, populations from Eneabba, Newdegate and the Die Hardy Range have been assessed by molecular characters. These findings, in conjunction with morphological investigations, have identified a new species and two new subspecies from within the ‘T. aphylla group’ and these are formally described here. Tetratheca nephelioides R.Butcher, is geographically restricted to the Eneabba area and has close morphological affinity to T. aphylla F.Muell. Tetratheca aphylla subsp. megacarpa R.Butcher, is restricted to the Newdegate area, some 300 km south of the only known populations of T. aphylla subsp. aphylla in the Helena and Aurora Range. Tetratheca paynterae Alford subsp. cremnobata R.Butcher is restricted to the Die Hardy Range, c. 10 km north-east of the only known population of T. paynterae subsp. paynterae at ‘Windarling’. All of these taxa are recognised as Declared Rare Flora. In the process of updating the existing key to ‘leafless’ species of Tetratheca to include these new taxa, two additional new species were identified from within collections of T. nuda Lindl. These are described here as T. angulata R.Butcher and T. applanata R.Butcher. Images and distribution maps for all taxa are provided.
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Hall, D. J. M., R. A. Sudmeyer, C. K. McLernon und R. J. Short. „Characterisation of a windbreak system on the south coast of Western Australia. 3. Soil water and hydrology“. Australian Journal of Experimental Agriculture 42, Nr. 6 (2002): 729. http://dx.doi.org/10.1071/ea02009.
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This paper describes changes in soil water and ground water at various distances from a Pinus pinaster windbreak in south-western Australia. Soil water contents were measured by neutron moisture meter and time domain reflectometry at distances from a windbreak ranging from 1 to 20 tree heights (H). Within 3 H of the windbreak, soil water storage was reduced by 100–153 mm/1.8 m when compared to unsheltered conditions (20 H) over the 4 years of the experiment. Beyond 3 H, no significant differences in soil water storage were found which could be related to microclimate modification. Relationships between surface soil water storage (mm/0.4 m) at <6�H and 12–24 H were 1 : 1 regardless of the technique used. Similarly, soil water depletion within the crop rootzone (mm/0.6 m) was similar at distances >3 H. Reductions in the depth and duration of perched water levels occurred within 4 H of the windbreak. Despite this, the windbreaks had no effect on the regional ground-water levels.
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Paynter, B. H., P. E. Juskiw und J. H. Helm. „Leaf development in two-row spring barley under long-day and short-day field conditions“. Canadian Journal of Plant Science 84, Nr. 2 (01.04.2004): 477–86. http://dx.doi.org/10.4141/p02-154.
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To gain an understanding of the adaptation of Australian and Canadian barley (Hordeum vulgare L.) cultivars to the environments of western Canada and Western Australia, phyllochron and number of leaves on the mainstem in eight cultivars of two-row, spring barley were examined when sown at two dates in two locations. The locations were a short-day environment at Northam, Western Australia, Australia in 1997 and a long-day environment at Lacombe, Alberta, Canada in 1998. At each location highly significant relationships between leaf number on the mainstem and thermal time were found (r2 > 0.94). Using linear estimates, the phyllochron of barley under short days was longer than under long days and was correlated to time to awn emergence. Later sowing shortened phyllochron under short days, but generally not under long days. Error messages from the linear regression analysis suggested that residuals were not random for all cultivars. Bilinear models were fitted to those datasets. Bilineal responses were observed under both short and long days, being independent of cultivar, date of seeding, final leaf number, phenological development pattern and time to awn emergence. The occurrence of a bilinear response was also independent of any ontogenetic events. The change in phyllochron occurred between leaves 4–7 at Northam and between leaves 6–9 at Lacombe. The leaf number at which the phyllochron change occurred was positively related to final leaf number and time to awn emergence. The phyllochron of early forming leaves was positively related to time to awn emergence and shorter than later forming leaves. Leaf emergence patterns in spring barley under both long-day and short-day conditions may therefore be linear or bilinear. Key words: barley (spring), Hordeum vulgare L., phyllochron, leaf emergence, daylength
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Holmes, Gareth D., Peter H. Weston, Daniel J. Murphy, Carolyn Connelly und David J. Cantrill. „The genealogy of geebungs: phylogenetic analysis of Persoonia (Proteaceae) and related genera in subfamily Persoonioideae“. Australian Systematic Botany 31, Nr. 2 (2018): 166. http://dx.doi.org/10.1071/sb16052.
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Proteaceae subfamily Persoonioideae, as presently circumscribed, consists of the monogeneric tribe Placospermeae (Placospermum) and the tribe Persoonieae. The latter comprises the diverse genus Persoonia and monospecific genera found in New Zealand (Toronia), New Caledonia (Garnieria) and south-western Western Australia (Acidonia). Persoonia has 101 species distributed across Australia and has been classified into 11 informal groups. Using data derived from plastid DNA (trnL–trnF region), nuclear rDNA (ITS) and morphological characters, we constructed a phylogeny of Persoonioideae and compared the results to the existing classification. Bayesian and parsimony analyses indicated that Persoonia, as currently defined, is non-monophyletic. The molecular data and combined molecular and morphological data place Toronia in a moderately well supported clade with the monophyletic Rufiflora group of Persoonia from Western Australia. This clade is sister to Acidonia, Garnieria and the remaining Persoonia species. Of the other informal groups in Persoonia, the Teretifolia, Quinquenervis, Laurina, Arborea, Graminea and Chapmaniana groups are supported as monophyletic. The Lanceolata group can be re-circumscribed to be monophyletic by the addition of P. elliptica R.Br. (Longifolia group) and the Dillwynioides group. Relationships within this large, geographically widespread clade are largely unresolved and low DNA-sequence variation within it suggests a recent radiation followed by isolation in south-western and eastern Australia. All endemic Tasmanian Persoonia (Gunnii group taxa) are unresolved at the second-most basal node of the Persoonieae. Our results suggest that the Rufiflora group should be treated as a new genus and that the infrageneric taxonomy of Persoonia requires minor amendment.
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Oliver, Paul M., Paul Doughty und Russell Palmer. „Hidden biodiversity in rare northern Australian vertebrates: the case of the clawless geckos (Crenadactylus, Diplodactylidae) of the Kimberley“. Wildlife Research 39, Nr. 5 (2012): 429. http://dx.doi.org/10.1071/wr12024.
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Context The phylogenetic diversity and biogeography of most animal and plant lineages endemic to the Australian Monsoonal tropics remains poorly understood. Of particular note (and in contrast to many other tropical regions in both Australia and elsewhere) is the current paucity of evidence for diverse endemic radiations of restricted-range taxa. Aims To use recently collected material from major surveys of the Kimberley Islands, Western Australia, to expand on a previous study that provided preliminary evidence of very high levels of geographically structured phylogenetic diversity in a lineage of tiny geckos (Crenadactylus). Methods Mitochondrial (ND2) and nuclear (RAG-1) sequence data were used to estimate the relationships, phylogenetic diversity and timescale of diversification of all populations of Crenadactylus from northern Australia from which samples for genetic analysis were available. Key results In striking contrast to the two subspecies currently recognised in the Kimberley, our analyses confirm the existence of a notable diversity of highly divergent and apparently allopatric lineages within the Kimberley, including at least 10 that are estimated to date to the late Pliocene/early Miocene (or earlier) and seven that we recognise as candidate new species. Most of this diversity is concentrated in the high-rainfall zone along the western edge of the Kimberley. Key conclusions A growing number of genetic datasets are revealing northern Australian vertebrate clades characterised by the juxtaposition of deeply divergent and highly geographically structured genetic diversity on the one hand, and major geographic gaps in sampling that impede full assessment of the distribution and taxonomic significance of this diversity on the other. Implications There is a pressing need for further surveys, voucher material and phylogenetic analyses to allow us to properly understand the diversity, biogeography and conservation needs of the northern Australian biota.
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O'Rourke, Tiernan A., Tim T. Scanlon, Megan H. Ryan, Len J. Wade, Alan C. McKay, Ian T. Riley, Hua Li, Krishnapillai Sivasithamparam und Martin J. Barbetti. „Severity of root rot in mature subterranean clover and associated fungal pathogens in the wheatbelt of Western Australia“. Crop and Pasture Science 60, Nr. 1 (2009): 43. http://dx.doi.org/10.1071/cp08187.
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Pasture decline is considered to be a serious challenge to agricultural productivity of subterranean clover across southern Australia. Root disease is a significant contributing factor to pasture decline. However, root disease assessments are generally carried out in the early part of the growing season and in areas predominantly sown to permanent pastures. For this reason, in spring 2004, a survey was undertaken to determine the severity of root disease in mature subterranean clover plants in pastures located in the wheatbelt of Western Australia. DNA-based soil assays were used to estimate population density in the soil of a variety of soil-borne pathogens known to commonly occur in the Mediterranean-type environments of southern Australia. The relationships between severity of disease on tap and lateral roots and root diameter, root length, nodulation, and total rainfall were determined. The survey showed, for the first time, that severe root disease is widespread in spring across the wheatbelt of Western Australia. There was a positive correlation between rainfall and tap root disease, and between tap root disease and average root diameter of the entire root system. Despite the high levels of root disease present across the sites, the DNA of most root disease pathogens assayed was detected in trace concentrations. Only Pythium Clade F showed high DNA concentrations in the soil. DNA concentrations in the soil, in particular for Phytophthora clandestina and Rhizoctonia solani AG 2.1 and AG 2.2, were higher in the smaller autumn sampling in 2006. This study suggests that the productivity of subterranean clover-based pastures is severely compromised by root rot diseases throughout the growing season in the wheatbelt of Western Australia.
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Hurse, T. J., und M. A. Connor. „A contour plot approach that uses data accumulated during routine monitoring to obtain insights into lagoon behaviour“. Water Science and Technology 42, Nr. 10-11 (01.11.2000): 91–98. http://dx.doi.org/10.2166/wst.2000.0616.
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Regular monitoring of wastewater characteristics is undertaken on most wastewater treatment plants. The data acquired during this process are usually filed and forgotten. However, systematic analysis of these data can provide useful insights into plant behaviour. Conventional graphical techniques are inadequate to give a good overall picture of how wastewater characteristics vary, with time and along the lagoon system. An approach based on the use of contour plots was devised that largely overcomes this problem. Superimposition of contour plots for different parameters can be used to gain a qualitative understanding of the nature and strength of relationships between the parameters. This is illustrated in an analysis of monitoring data for lagoon 115 East at the Western Treatment Plant, near Melbourne, Australia. In this illustrative analysis, relationships between ammonia removal rates and parameters such as chlorophyll a level and temperature are explored using a contour plot superimposition approach. It is concluded that this approach can help improve our understanding, not only of lagoon systems, but of other wastewater treatment systems as well.
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Stukely, Michael JC. „New Phytophthoras in Western Australia’s natural ecosystems“. Microbiology Australia 33, Nr. 1 (2012): 31. http://dx.doi.org/10.1071/ma12031.
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Phytophthora spp. are recognised as important plant pathogens. Ten new and genetically diverse species, not previously reported from elsewhere, have recently been described from natural ecosystems in Western Australia (WA): Phytophthora multivora1; P. elongata; P. thermophila, P. gregata, P. gibbosa, P. litoralis; P. arenaria, P. constricta; P. fluvialis; and P. amnicola. They were identified by DNA sequencing of recent and historical isolates from the WA Department of Environment and Conservation (DEC). Several additional new taxa await description. New records for WA of at least eight other Phytophthora taxa that are known overseas, some of them as yet undescribed, have also been confirmed: P. inundata; P. taxon niederhauserii, P. taxon asparagi, P. taxon PgChlamydo, P. taxon personii; P. taxon salixsoil; P. palmivora and P. rosacearum. Furthermore, numerous Phytophthora hybrids have been identified in natural vegetation and waterways in WA. The phylogenetic relationships of the new WA Phytophthora taxa, with their nearest relatives, are shown in Figure 1.
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Cochrane, Anne, Anne Kelly, Kate Brown und Simone Cunneen. „Relationships between seed germination requirements and ecophysiological characteristics aid the recovery of threatened native plant species in Western Australia“. Ecological Management and Restoration 3, Nr. 1 (April 2002): 47–60. http://dx.doi.org/10.1046/j.1442-8903.2002.00089.x.
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Sgherza, Ciaran, Louise E. Cullen und Pauline F. Grierson. „Climate relationships with tree-ring width and δ13C of three Callitris species from semiarid woodlands in south-western Australia“. Australian Journal of Botany 58, Nr. 3 (2010): 175. http://dx.doi.org/10.1071/bt09222.
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Proxy measures of climate based on tree rings can allow reconstruction of climate back past the limit of instrumental records, thereby improving understanding of natural climate variability. We assessed the dendroclimatic potential of tree-ring widths and δ13C of three broadly co-occurring species of Callitris in south-western Western Australia. Ring width chronologies of C. columellaris F.Muell., C. canescens (Parl.) S.T. Blake and C. preissii Miq. met standard measures of dendrochronological acceptability. For all three species, the Expressed Population Signal (EPS) was >0.93 and mean correlations between series in each chronology was >0.79. In contrast, δ13C chronologies were of poorer statistical quality (EPS ranged 0.59 to 0.88, mean correlations ranged 0.33 to 0.65) with both less year-to-year and lower-frequency information (lower mean sensitivity and standard deviation values). The dominant climatic signal in the ring width chronologies was related to rainfall and was strongest over the March–September season (correlations ranged 0.27 to 0.70, all P < 0.05). Consistent with the poorer quality of the δ13C chronologies compared with those from ring widths, tree-ring δ13C was also less strongly correlated with rainfall and rarely significant (P = 0.05). The weaker δ13C correlations may be due to a strong water conservation strategy by Callitris. Our analysis of the whole ring rather than latewood and low sampling effort may also have dampened the δ13C response. However, combining the ring width and δ13C chronologies using Principal Components Analysis did not enhance the extraction of a climatic signal. While the variance explained by the first principal component (PC) was high for all three species (76 to 87%), correlations between the first PC and rainfall were not stronger than for ring widths alone. Tree-ring δ13C, in conjunction with δ18O in particular, may nevertheless provide insight into physiological responses of Callitris to climate variation. However, dendroclimatic studies using Callitris to develop past rainfall records should focus on developing chronologies from ring widths. Further effort to find sites with old trees (250 years or more) should be undertaken and are likely to provide much needed information on past rainfall in Australia.
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Baek, C. W., und N. Coles. „The influence of antecedent soil moisture conditions on the rainfall–runoff threshold value of a roaded catchment used for water harvesting“. Water Supply 13, Nr. 5 (01.09.2013): 1202–8. http://dx.doi.org/10.2166/ws.2013.128.
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A roaded catchment (RC) is a representative type of artificial catchment for rainwater harvesting. The rainfall–runoff threshold value of the RC is the main factor which influences the system efficiency and cost. Antecedent soil moisture condition is an important factor which impacts on the determination of the rainfall–runoff threshold value. In this study, rainfall–antecedent soil moisture condition–runoff relationships and the potential efficiency of RCs are presented. Rainfall and runoff data monitored at research sites in Merredin and Mount Barker are used to determine this relationship. Two antecedent moisture criteria; Antecedent Moisture Conditions (AMC) and Average Antecedent Precipitation (AAP) are used to analyse the relationship between previous rainfall and soil moisture for each RC. Monitored results show that AMC is not that suitable to show the relationship between rainfall and antecedent soil moisture condition of the RC in the dryland of Western Australia and it is recommended to use AAP to determine this relationship.
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Nagy, KA, AJ Bradley und KD Morris. „Field Metabolic Rates, Water Fluxes, and Feeding Rates of Quokkas, Setonix-Brachyurus, and Tammars, Macropus-Eugenii, in Western-Australia“. Australian Journal of Zoology 37, Nr. 5 (1989): 553. http://dx.doi.org/10.1071/zo9890553.
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Field metabolic rates (FMRS) and water influx rates were measured by means of doubly labelled water in free-ranging quokkas living on Rottnest I, and free-ranging tammar wallabies living on Garden I. Feeding rates were estimated from energy requirements. Quokkas ranging in body mass from 1.44 to 2.83 kg (mean 1.90 kg) had FMRS averaging 0.574 mL C02 (g.h)-', which is equivalent to 548 kJ d-'. Their rates of total water intake averaged 47.3 mL (kg.d)-', or 90.5 mL d-'. Estimated feeding rate was 54.8 g (dry matter) per day, and water ingested as part of the food (preformed and metabolically produced) can completely account for total water intake. We believe that quokkas did not drink water during our field measurements. Tammars ranging in body mass from 3.20 to 6.35 kg (mean 4.38 kg) had FMRS averaging 0.518 mL CO2 (g.h)-', which is equivalent to 1150 kJ d-'. Their rates of water influx averaged 57.5 mL (kg.d)-', or 270 mL d-', and their estimated feeding rate was 115 g (dry matter) per day. Tammars also probably did not drink free-standing water during our study. FMRs of quokkas averaged 1 .80 x basal metabolic rate (BMR), and FMRS of tammars averaged 1.87 x BMR; this difference is not significant. We estimate that the 5000 quokkas on Rottnest I. consume at least 100 000 kg of plant matter (dry mass) per year, and the 2173 tammars on Garden I. ingest more than 90 000 kg. Measurements of food availability are needed to permit evaluation of the relationship between food supply and demand for these two populations of macropod marsupials.
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Mahmud, K., G. Mariethoz, A. Baker, P. C. Treble, M. Markowska und E. McGuire. „Estimation of deep infiltration in unsaturated limestone environments using cave lidar and drip count data“. Hydrology and Earth System Sciences 20, Nr. 1 (20.01.2016): 359–73. http://dx.doi.org/10.5194/hess-20-359-2016.
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Abstract. Limestone aeolianites constitute karstic aquifers covering much of the western and southern Australian coastal fringe. They are a key groundwater resource for a range of industries such as winery and tourism, and provide important ecosystem services such as habitat for stygofauna. Moreover, recharge estimation is important for understanding the water cycle, for contaminant transport, for water management, and for stalagmite-based paleoclimate reconstructions. Caves offer a natural inception point to observe both the long-term groundwater recharge and the preferential movement of water through the unsaturated zone of such limestone. With the availability of automated drip rate logging systems and remote sensing techniques, it is now possible to deploy the combination of these methods for larger-scale studies of infiltration processes within a cave. In this study, we utilize a spatial survey of automated cave drip monitoring in two large chambers of Golgotha Cave, south-western Western Australia (SWWA), with the aim of better understanding infiltration water movement and the relationship between infiltration, stalactite morphology, and unsaturated zone recharge. By applying morphological analysis of ceiling features from Terrestrial LiDAR (T-LiDAR) data, coupled with drip time series and climate data from 2012 to 2014, we demonstrate the nature of the relationships between infiltration through fractures in the limestone and unsaturated zone recharge. Similarities between drip rate time series are interpreted in terms of flow patterns, cave chamber morphology, and lithology. Moreover, we develop a new technique to estimate recharge in large-scale caves, engaging flow classification to determine the cave ceiling area covered by each flow category and drip data for the entire observation period, to calculate the total volume of cave discharge. This new technique can be applied to other cave sites to identify highly focussed areas of recharge and can help to better estimate the total recharge volume.
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Walker, E., M. Byrne, B. Macdonald, D. Nicolle und J. McComb. „Clonality and hybrid origin of the rare Eucalyptus bennettiae (Myrtaceae) in Western Australia“. Australian Journal of Botany 57, Nr. 3 (2009): 180. http://dx.doi.org/10.1071/bt08148.
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Clonality and hybrid origin influence the conservation status of rare and restricted species. Eucalyptus bennettiae Carr & Carr is a rare species known only from a few individuals that may be clonal and may have arisen through hybridisation between other co-occurring species. The hybrid status and clonality of E. bennettiae was investigated with analysis of microsatellite variation in E. bennettiae compared with its putative parents, E. lehmannii subsp. parallela, E. sporadica and E. astringens subsp. redacta, identified through morphological characteristics. Analysis of microsatellite variation revealed clonality with one individual present at each location, and additivity of alleles and no unique alleles in E. bennettiae compared with two of the putative parents, E. lehmannii subsp. parallela and E. sporadica. In addition, E. bennettiae displayed intermediacy in species relationships and measures of relatedness, and assignment tests showed mixed ancestry in relation to these species but not the third putative parent, E. astringens subsp. redacta. These findings confirm that E. bennettiae is a hybrid and evaluation of the taxon for conservation protection shows that it does not satisfy the criteria for listing as a threatened species.
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Carolin, R. „A Review of the Family Portulacaceae“. Australian Journal of Botany 35, Nr. 4 (1987): 383. http://dx.doi.org/10.1071/bt9870383.
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A number of attributes that has proved useful to delimit subfamilial taxa within the Portulacaceae are critically assessed and some little used ones are introduced. The attributes are polarised by an outgroup comparison and a Wagner tree constructed. Some reversals which occur on this tree are considered unacceptable and branches are moved to eliminate this factor, although a longer tree, in terms of character state changes, is produced. A phylogenetic sequence is proposed on this basis and a new classification of the family attempted. On the basis of these results it is suggested that: (1) the genus Calandrinia s.1. be divided into five genera; (2) the genera Talinaria and Anacampseros are closely related; (3) Talinum may not be a natural genus; (4) the family can be conveniently divided into five tribes. A biogeographical analysis indicates that closer floristic relationships exist between western America and Australia and between eastern America and Africa than between eastern and western America or between Australia and Africa.
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Javidkar, Mohammad, Steven J. B. Cooper, Rachael A. King, William F. Humphreys und Andrew D. Austin. „Molecular phylogenetic analyses reveal a new southern hemisphere oniscidean family (Crustacea : Isopoda) with a unique water transport system“. Invertebrate Systematics 29, Nr. 6 (2015): 554. http://dx.doi.org/10.1071/is15010.
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A significant diversity of terrestrial oniscidean isopods was recently discovered in the subterranean ‘calcrete islands’ of Western Australia, but the species and higher-level systematic status of much of the fauna are currently uncertain. Here we focus on one group of species that was initially assigned to the genus Trichorhina (Platyarthridae), based on several shared characters, and investigate the phylogenetic relationships of these species to 21 oniscidean genera, including 13 known families, using 18S rDNA sequence data. We then present phylogenetic analyses using 28S-only and combined 18S, 28S rDNA and mitochondrial cytochrome c oxidase subunit I (COI) data for a more restricted sampling of taxa, and present results for a detailed morphological study of the antennae and other cephalic structures of exemplar taxa. Bayesian and maximum likelihood analyses of the extended 18S-only, the 28S-only and multi-gene datasets provide strong evidence for a distinct well-supported monophyletic group comprising the new Western Australian and one South American taxon. This clade is unrelated to all included members of Platyarthridae, which appears to be polyphyletic, and it forms a distinct group relative to other oniscidean families. Given these findings and the results of the morphological study, a new southern hemisphere oniscidean family, Paraplatyarthridae Javidkar & King, fam. nov. is erected based on Paraplatyarthrus subterraneus Javidkar & King, gen. & sp. nov. (type genus and species), and several undescribed taxa which occur in the arid (terrestrial and subterranean) regions of Western Australia and subtropical South America. Paraplatyarthridae is distinguishable from all other oniscidian families on a combination of character states including, among others, the presence of fan-like scale setae on the dorsal body, and the ventral second antenna with leaf-like scale setae and a furrow containing elongated hair-like capillary setae that form part of a water conducting system unique within Oniscidea. This study has important implications for the higher-level classification of oniscidean crustaceans and points to the need for a more detailed molecular phylogeny that includes a comprehensive sampling of southern hemisphere taxa.
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Lund, Mark A., und Jennifer A. Davis. „Seasonal dynamics of plankton communities and water chemistry in a eutrophic wetland (Lake Monger, Western Australia): implications for biomanipulation“. Marine and Freshwater Research 51, Nr. 4 (2000): 321. http://dx.doi.org/10.1071/mf97081.
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In a large (70 ha) shallow (<2m deep) eutrophic wetland investigated between November 1988 and October 1989, there were marked seasonal changes in water quality and the composition of zooplankton, and to a lesser extent phytoplankton communities, with three distinct groupings evident: summer, winter–spring and autumn. Summer conditions were characterized by high levels of total P (689198 ˜g L –1 ), N limitation, blooms of Microcystis aeruginosa (mean chlorophyll a = 46630 ˜g L –1 ) and zooplankton communities dominated by cyclopoid copepods (Mesocyclops sp. and Microcyclops sp.). Winter–spring conditions were characterized by Secchi disk transparencies to the bed (chlorophyll a <50 ˜g L –1 ), low total P (7140 ˜g L–1 ) and zooplankton communities dominated byDaphnia carinata King. Autumn conditions represented an intermediate state between these two. Significant linear relationships were recorded between chlorophyll a and total P and between chlorophyll a and D. carinata. Abundances of hemipteran predators (Anisops sp.) were correlated with D. carinata, but the relationship did not appear to be causal. The decline in D. carinata in summer was attributed to food limitation. Reductions in nutrient inputs to the lake in 1990–91, resulted in improved water quality and high abundances of D. carinata during summer.
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Perina, Giulia, Ana I. Camacho, Joel Huey, Pierre Horwitz und Annette Koenders. „New Bathynellidae (Crustacea) taxa and their relationships in the Fortescue catchment aquifers of the Pilbara region, Western Australia“. Systematics and Biodiversity 17, Nr. 2 (17.02.2019): 148–64. http://dx.doi.org/10.1080/14772000.2018.1559892.
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Vincent, Brian J., Sarah Barrett, Anne Cochrane und Michael Renton. „Germination characteristics and the relationship between population structure, soil seed bank density and fire response in the rare endemic Stachystemon vinosus (Halford & R.J.F.Hend.) (Euphorbiaceae) from southern Western Australia“. Seed Science Research 29, Nr. 2 (Juni 2019): 124–34. http://dx.doi.org/10.1017/s0960258519000126.
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AbstractThe regeneration niche defines the specific environmental requirements of the early phases of a plant's life cycle. It is critical for the long-term persistence of plant populations, particularly for obligate seeders that are highly vulnerable to stochastic events in fire-prone ecosystems. Here, we assessed germination characteristics and the relationship between population structure, soil seed bank density and fire response in Stachystemon vinosus (Euphorbiaceae), a rare endemic shrub from Western Australia, from burnt and long unburnt habitats. Many plants in long unburnt habitat were similar in size to those in recently burnt habitat. Soil seed bank density was related to plant abundance and fire history with density lower in burnt than unburnt sites. Thus, inter-fire recruitment may play a critical role in the requirements of the study species. To assess the dormancy status and germination requirements we used a ‘move-along’ experiment with temperatures from six seasonal phases of the year. Seeds were incubated under light and dark conditions, with and without smoked water, and with and without dry after-ripening. Germination was most effective when seeds were treated with smoked water and incubated in the dark at temperatures resembling autumn/winter conditions. After-ripening increased germination in light and dark incubated seeds in the absence of smoked water but was unnecessary for optimal germination in smoked water treated seeds. Irrespective of treatment, seeds showed a requirement for cooler temperatures for germination. These results suggest that rising temperatures and changes in fire regime associated with global warming may alter future germination responses of Stachystemon vinosus.
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McKirdy, S. J., R. A. C. Jones und F. W. Nutter. „Quantification of Yield Losses Caused by Barley yellow dwarf virus in Wheat and Oats“. Plant Disease 86, Nr. 7 (Juli 2002): 769–73. http://dx.doi.org/10.1094/pdis.2002.86.7.769.
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Grain yield data obtained from five field experiments in Western Australia from 1992 to 1994, in which insecticide applications suppressed the spread of Barley yellow dwarf virus (BYDV) in wheat and oats, were used to quantify the relationships between incidence of BYDV and yield gaps, 500-seed weight, and percent shriveled grain. Yield gaps ranged from 0 to 2,700 kg/ha, and the relationship between yield gap and incidence of BYDV was always linear. Single point yield loss models revealed that BYDV infection explained most of the variation in yield gaps. There was a significant linear relationship between incidence of BYDV and 500-seed weight for wheat, but not for oats. The percent shriveled grain always increased with an increase in incidence of BYDV in wheat but not in oats. Cost-benefit relationships were determined for the return on investment when deploying imidacloprid-treated seed and/or one or two foliar applications of pyrethroid insecticides to reduce incidence of BYDV and to decrease the yield gaps in wheat and oats due to BYDV.
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Broadhurst, Linda, Margaret Byrne, Lyn Craven und Brendan Lepschi. „Genetic congruence with new species boundaries in the Melaleuca uncinata complex (Myrtaceae)“. Australian Journal of Botany 52, Nr. 6 (2004): 729. http://dx.doi.org/10.1071/bt04073.
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Uninformed management decisions have the potential to create significant problems for conservation programs. In the south-western corner of Australia where conservation initiatives are directed towards restoring large tracts of land degraded by broadscale clearing and increasing levels of dryland salinity, Melaleuca uncinata R.Br. (Myrtaceae) is a species complex of considerable interest for restoration. Although M. uncinata is morphologically uniform across most of southern mainland Australia, there is considerable variation in south-western Australia and a recent morphological evaluation has recognised 11 species. Phylogenetic patterns among populations of seven of these species were examined with nuclear RFLP loci to determine whether morphological and phylogenetic boundaries were congruent before the implementation of any broadscale revegetation programs. The phylogenetic analysis was congruent with the morphological assessment, and populations of different species, including those co-occurring at the same site, clustered according to their correct morphological assignment. Some genetic structuring associated with habitat preference was also evident within two of the species. The taxonomic resolution and knowledge of the phylogenetic relationships among the seven species will facilitate their further assessment for issues relevant to revegetation, such as provenance and local adaptation. It will also enable selection of appropriate germplasm in revegetation programs to maximise the genetic adaptation in restoration and minimise negative impact of plantings on remnant vegetation.
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Byrne, M., und L. Broadhurst. „Genetic diversity and the utilisation of Acacia species complexes in agroforestry in Western Australia“. Australian Systematic Botany 16, Nr. 1 (2003): 49. http://dx.doi.org/10.1071/sb01037.
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Dryland salinity is a major problem in the agricultural areas of Western Australia, having significant detrimental impacts in both agricultural and non-agricultural arenas. Development of new woody perennial tree crops is an option for recharge control in the management of salinity and there is a focus on development of native species that are adapted to low-rainfall areas, with potential for commercial production. Acacia is an important genus for utilisation of woody perennials as there is a large number of species occurring in a wide variety of habitats, and many Acacia species are utilised throughout the world for a range of purposes. In Western Australia, the following three species are of interest for development for commercial utilisation in agroforestry plantings: A.�microbotrya, A. acuminata and A. saligna. All three species show a high degree of morphological variation and are likely to consist of several taxa. Lack of understanding of taxonomic entities and their genetic relationships will hinder the utilisation and development of these species. A combined genetic and taxonomic study has defined the morphological and genetic variation within the A. acuminata complex and identified several taxa. Similar studies will also be expected to define taxa within the A. microbotrya and A. saligna complexes.
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Gosper, Carl R., Suzanne M. Prober, Colin J. Yates und Georg Wiehl. „Estimating the time since fire of long-unburnt Eucalyptus salubris (Myrtaceae) stands in the Great Western Woodlands“. Australian Journal of Botany 61, Nr. 1 (2013): 11. http://dx.doi.org/10.1071/bt12212.
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Establishing the time since fire in infrequently burnt, yet fire-prone, communities is a significant challenge. Until this can be resolved for >50-year timeframes, our capacity to understand important ecological processes, such as the periods required for development of habitat features, will remain limited. We characterised the relationship between observable tree growth rings, plant age and plant size in Eucalyptus salubris F.Muell. in the globally significant Great Western Woodlands in south-western Australia. In the context of recent concerns regarding high woodland fire occurrence, we then used this approach to estimate the age of long-unburnt E. salubris stands, and the age-class distribution of Eucalyptus woodlands across the region. Time since fire was strongly predicted by trunk growth rings and plant size predicted growth rings with reasonable accuracy. The best model estimating growth rings contained parameters for trunk diameter, plant height and plot location, although simple models including either trunk diameter or plant height were nearly as good. Using growth ring–size relationships to date long-unburnt stands represents a significant advance over the current approach based on satellite imagery, which substantially truncates post-fire age. However, there was significant uncertainty over the best model form for estimating the time since fire of stands last burnt over 200 years ago. The management implications of predicted age-class distributions were highly dependent on both the choice of what, if any, transformation was applied to growth rings, and the theoretical age-class distribution to which the actual age-class distribution was compared.
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Bell, DT, S. Vlahos und LE Watson. „Stimulation of Seed-Germination of Understorey Species of the Northern Jarrah Forest of Western-Australia“. Australian Journal of Botany 35, Nr. 5 (1987): 593. http://dx.doi.org/10.1071/bt9870593.
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Glasshouse trials in trays of soil measured the germination response to high temperatures and the presence of charcoal in 40 non-leguminous understorey species of the northern jarrah (Eucalyptus marginata Donn ex Smith) forest. Species producing relatively low proportions of viable and germinable seeds tended to be the long-lived resprouting species where reproductive output may not be of major adaptive significance. Three species, Conostylis setosa, Trymalium ledifolium and T. spathulaturn, with seed stored in the soil, were stimulated to germinate by high temperatures. Bradysporous, obligate reseeding species showed either no temperature effect (mainly species of Dryandra) or death at high temperatures (species of Hakea, whose seeds normally are protected by woody fruits). Charred wood of Eucalyptus marginata induced an increase in the proportion of Burchardia umbellata germinating under the test conditions. Relationships of the seed germination results to aspects of r- and K- selection theory and fire management policy in the northern jarrah forest are also discussed.
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Pate, JS, NE Casson, J. Rullo und J. Kuo. „Biology of Fire Ephemerals of the Sandplains of the Kwongan of South-Western Australia“. Functional Plant Biology 12, Nr. 6 (1985): 641. http://dx.doi.org/10.1071/pp9850641.
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The growth, longevity, mineral relationships and reproductive biology of 18 species of fire ephemerals were examined in sclerophyllous shrubland, located mainly within the Jurien : Badgingarra region of the Northern Sandplains of the kwongan of SW. Australia. Ten of the species were monocarpic, completing their life cycle within the 6-8 month winter growing season after a summer or autumn fire. The remaining species were polycarpic, commencing reproduction in their second season and surviving and reproducing for a further two to eight seasons (depending on species). Detailed study was made of growth and dry matter allocation in the dioecious, sexually dimorphic, polycarpic species Tersonia brevipes (Gyrostemonaceae). Monocarpic species tended to produce smaller seeds, and exhibited greater seed output per unit biomass and higher harvest indices for dry matter and minerals than polycarpic species. Certain monocarpic species showed great plasticity in final dry weight, e.g. a 2700-fold difference between largest and smallest individuals in a sample of 250 plants of Stipa elegantissima (Poaceae), and a 180-fold range in a similarly sized sample of Macarthuria apetala (Aizoaceae). The fire ephemerals studied generally exhibited faster seedling growth rates, greater concentrations of P and N (but not of Ca, Mg and K) in seedling dry matter, but usually lesser concentrations of P and N (but not of Ca, Mg and K) in seed dry matter than in cohabiting obligate seeder or sprouter species with potential life spans exceeding 15 years. The above-mentioned features of fire ephemerals are suggested to be of special adaptive significance within the context of exploitation of transiently non-limiting habitat resources immediately following fire.