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Zeitschriftenartikel zum Thema "Phylogeography – Western Australia – South-West"

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Byrne, M. „Phylogeography provides an evolutionary context for the conservation of a diverse and ancient flora“. Australian Journal of Botany 55, Nr. 3 (2007): 316. http://dx.doi.org/10.1071/bt06072.

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Phylogeography can inform conservation strategies through assessment of genetic diversity that incorporates an evolutionary perspective, and allows evaluation within a geographical context, thus providing integration with other biogeographical information. Comparative phylogeography can identify significant historical processes that have had major influences on the biota and provides a historical context for understanding current species distributions. The phylogeographic patterns in the flora of south-western Australia are reviewed. Concordant patterns of lineage divergence in three unrelated taxa from separate families with widespread distributions indicate a common response to major historical processes involved in Pleistocene climatic fluctuations. Identification of highly divergent haplotypes in some species indicates areas that may represent refugia during times of climatic instability. Analysis of phylogeographic patterns in the flora of south-western Australia has revealed the influence of historical climate change in promoting high phylogenetic diversity within species that is comparable to the high species diversity that is well known in the Western Australian flora. Knowledge of historical influences and species responses provides an evolutionary context for conservation management strategies that facilitate the continued action of dynamic evolutionary processes.
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Gouws, Gavin, Barbara A. Stewart und Savel R. Daniels. „Phylogeographic structure of a freshwater crayfish (Decapoda:Parastacidae:Cherax preissii) in south-western Australia“. Marine and Freshwater Research 57, Nr. 8 (2006): 837. http://dx.doi.org/10.1071/mf05248.

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Although phylogeographic patterns of freshwater decapods elsewhere in Australia are well documented, little is known of the phylogeography and biogeography of the endemic freshwater fauna of south-western Australia. Here, the phylogeographic structure of a freshwater crayfish, Cherax preissii Erichson, 1846, was investigated to determine contemporary and historical patterns of gene flow and to examined evolutionary and biogeographical scenarios. Allozyme and cytochrome c oxidase subunit I mitochondrial DNA data were collected from 15 populations, sampled across the known C. preissii distribution. Both markers revealed a clear distinction and separation among populations occurring in the north-western and southern portions of the distribution. Inferences of allopatric fragmentation and molecular dating attributed the divergence of the aquatic fauna of these regions to periods of Pliocene–Pleistocene aridity. Connectivity appeared to be greater within each of these regions. Evidence suggested contemporary, but not ongoing, gene flow, particularly within the southern region. This was possibly facilitated by dispersal during pluvial Pleistocene periods or drainage connectivity during episodic marine regressions. The divergence and distributions of these lineages parallels patterns seen in other freshwater crayfish of the region. More explicit investigation of these and further fine-scale phylogeographic studies may contribute to the understanding of biogeography and evolution in the south-west, and may further refine currently recognised biogeographical regions.
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Harms, Danilo, J. Dale Roberts und Mark S. Harvey. „Climate variability impacts on diversification processes in a biodiversity hotspot: a phylogeography of ancient pseudoscorpions in south-western Australia“. Zoological Journal of the Linnean Society 186, Nr. 4 (12.04.2019): 934–49. http://dx.doi.org/10.1093/zoolinnean/zlz010.

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Abstract The south-western division of Australia is the only biodiversity hotspot in Australia and is well-known for extreme levels of local endemism. Climate change has been identified as a key threat for flora and fauna, but very few data are presently available to evaluate its impact on invertebrate fauna. Here, we derive a molecular phylogeography for pseudoscorpions of the genus Pseudotyrannochthonius that in the south-west are restricted to regions with the highest rainfall. A dated molecular phylogeny derived from six gene fragments is used for biogeographic reconstruction analyses, spatial mapping, environmental niche-modelling, and to infer putative species. Phylogenetic analyses uncover nine clades with mostly allopatric distributions and often small linear ranges between 0.5 and 130 km. Molecular dating suggests that the origins of contemporary diversity fall into a period of warm/humid Palaeogene climates, but splits in the phylogeny coincide with major environmental shifts, such as significant global cooling during the Middle Miocene. By testing several models of historical biogeography available for the south-west, we determine that Pseudotyrannochthonius is an ancient relict lineage that principally follows a model of allopatric speciation in mesic zone refugia, although there are derivations from this model in that some species are older and distribution patterns more complex than expected. Ecological niche models indicate that drier and warmer future climates will lead to range contraction towards refugia of highest rainfall, probably mimicking past variations that have generated high diversity in these areas. Their conservation management will be crucial for preserving the unique biodiversity heritage of the south-west.
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Cooper, Steven J. B., Kym Ottewell, Anna J. MacDonald, Mark Adams, Margaret Byrne, Susan M. Carthew, Mark D. B. Eldridge et al. „Phylogeography of southern brown and golden bandicoots: implications for the taxonomy and distribution of endangered subspecies and species“. Australian Journal of Zoology 66, Nr. 6 (2018): 379. http://dx.doi.org/10.1071/zo19052.

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Southern brown (Isoodon obesulus) and golden (Isoodon auratus) bandicoots are iconic Australian marsupials that have experienced dramatic declines since European settlement. Conservation management programs seek to protect the remaining populations; however, these programs are impeded by major taxonomic uncertainties. We investigated the history of population connectivity to inform subspecies and species boundaries through a broad-scale phylogeographic and population genetic analysis of Isoodon taxa. Our analyses reveal a major east–west phylogeographic split within I. obesulus/I. auratus, supported by both mtDNA and nuclear gene analyses, which is not coincident with the current species or subspecies taxonomy. In the eastern lineage, all Tasmanian samples formed a distinct monophyletic haplotype group to the exclusion of all mainland samples, indicative of long-term isolation of this population from mainland Australia and providing support for retention of the subspecific status of the Tasmanian population (I. o. affinis). Analyses further suggest that I. o. obesulus is limited to south-eastern mainland Australia, representing a significant reduction in known range. However, the analyses provide no clear consensus on the taxonomic status of bandicoot populations within the western lineage, with further analyses required, ideally incorporating data from historical museum specimens to fill distributional gaps.
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Wheeler, M. A., und M. Byrne. „Congruence between phylogeographic patterns in cpDNA variation in Eucalyptus marginata (Myrtaceae) and geomorphology of the Darling Plateau, south-west of Western Australia“. Australian Journal of Botany 54, Nr. 1 (2006): 17. http://dx.doi.org/10.1071/bt05086.

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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.
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Colgan, D. J., D. O'Meally und R. A. Sadlier. „Phylogeographic patterns in reptiles on the New England Tablelands at the south-western boundary of the McPherson Macleay Overlap“. Australian Journal of Zoology 57, Nr. 5 (2009): 317. http://dx.doi.org/10.1071/zo08088.

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Phylogeographic studies of eastern Australia have generally supported earlier biogeographical studies based on taxon distributions by concurring in the placement of significant intraspecific boundaries. Such studies may potentially clarify biogeographic boundaries that are presently unclear, such as the poorly defined southern edges of the McPherson Macleay Overlap. Here we investigate reptile phylogeography in the northern tablelands of New South Wales to study the south-western boundaries of the Overlap as these are especially uncertain. Cytochrome b sequences from Ctenotus robustus, C. taeniolatus and Oedura lesueurii, three lizard species widespread across the New England Tablelands, were analysed by examining single-strand conformational polymorphism and DNA sequencing. In both O. lesueurii and C. taeniolatus most deeper nodes within species define geographically localised clades. This was not the case for C. robustus. Boundaries between sister-group clades were discovered in multiple locations in the region – between Glen Innes and Armidale, between Armidale and Tamworth and to the south of the Liverpool Plains. The boundaries in C. taeniolatus and O. lesueurii were probably formed in at least two different periods. The phylogeographic patterns may be partly explained by glacially induced aridity cycles in the early Pleistocene or before.
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Li, You, Melanie L. Lancaster, Susan M. Carthew, Jasmin G. Packer und Steven J. B. Cooper. „Delineation of conservation units in an endangered marsupial, the southern brown bandicoot (Isoodon obesulus obesulus), in South Australia/western Victoria, Australia“. Australian Journal of Zoology 62, Nr. 5 (2014): 345. http://dx.doi.org/10.1071/zo14038.

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Conservation programs for threatened species are greatly benefiting from genetic data, for their power in providing knowledge of dispersal/gene flow across fragmented landscapes and for identifying populations of high conservation value. The endangered southern brown bandicoot (Isoodon obesulus obesulus) has a disjunct distribution range in South Australia, raising the possibility that populations of the subspecies may represent distinct conservation units. In the current study, we used a combination of 14 microsatellite and two mitochondrial sequence markers to investigate the phylogeography and population structure of I. o. obesulus in South Australia and south-western Victoria, with the aim of identifying any potential evolutionarily significant units and management units relevant to conservation management. Our phylogenetic/population analyses supported the presence of two distinct evolutionary lineages of I. o. obesulus. The first lineage comprised individuals from the Mount Lofty Ranges, Fleurieu Peninsula and Kangaroo Island. A second lineage comprised individuals from the south-east of South Australia and south-western Victoria. We propose that these two lineages represent distinct evolutionarily significant units and should be managed separately for conservation purposes. The findings also raise significant issues for the national conservation status of I. o. obesulus and suggest that the current subspecies classification needs further investigation.
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Schwentner, Martin, und Gonzalo Giribet. „Phylogeography, species delimitation and population structure of a Western Australian short-range endemic mite harvestman (Arachnida: Opiliones: Pettalidae: Karripurcellia)“. Evolutionary Systematics 2, Nr. 1 (26.06.2018): 81–87. http://dx.doi.org/10.3897/evolsyst.2.25274.

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The mite harvestmen of the genusKarripurcelliaGiribet, 2003 are endemic to the tall, wet eucalypt forests of south-western Western Australia, a region known as a hotspot for biodiversity. Currently, there are two accepted species,K.peckorumGiribet, 2003 andK.sierwaldaeGiribet, 2003, both with type localities within the Warren National Park. We obtained 65COImtDNA sequences from across the entire distributional range of the genus. These sequences, falling into two to three geographically separate groups, probably correspond to two species. Morphologically, all of the studied specimens correspond toK.peckorum, suggesting cryptic speciation within that species. A few common haplotypes occur in more than one population, but most haplotypes are confined to a single population. As a result, populations are genetically differentiated and gene flow after initial colonization appears to be very limited or completely lacking. Our study provides another example of short-range endemism in an invertebrate from the south-western mesic biome.
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Eden, John-Sebastian, John Kovaliski, Janine A. Duckworth, Grace Swain, Jackie E. Mahar, Tanja Strive und Edward C. Holmes. „Comparative Phylodynamics of Rabbit Hemorrhagic Disease Virus in Australia and New Zealand“. Journal of Virology 89, Nr. 18 (08.07.2015): 9548–58. http://dx.doi.org/10.1128/jvi.01100-15.

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ABSTRACTThe introduction of rabbit hemorrhagic disease virus (RHDV) into Australia and New Zealand during the 1990s as a means of controlling feral rabbits is an important case study in viral emergence. Both epidemics are exceptional in that the founder viruses share an origin and the timing of their release is known, providing a unique opportunity to compare the evolution of a single virus in distinct naive populations. We examined the evolution and spread of RHDV in Australia and New Zealand through a genome-wide evolutionary analysis, including data from 28 newly sequenced RHDV field isolates. Following the release of the Australian inoculum strain into New Zealand, no subsequent mixing of the populations occurred, with viruses from both countries forming distinct groups. Strikingly, the rate of evolution in the capsid gene was higher in the Australian viruses than in those from New Zealand, most likely due to the presence of transient deleterious mutations in the former. However, estimates of both substitution rates and population dynamics were strongly sample dependent, such that small changes in sample composition had an important impact on evolutionary parameters. Phylogeographic analysis revealed a clear spatial structure in the Australian RHDV strains, with a major division between those viruses from western and eastern states. Importantly, RHDV sequences from the state where the virus was first released, South Australia, had the greatest diversity and were diffuse throughout both geographic lineages, such that this region was likely a source population for the subsequent spread of the virus across the country.IMPORTANCEMost studies of viral emergence lack detailed knowledge about which strains were founders for the outbreak or when these events occurred. Hence, the human-mediated introduction of rabbit hemorrhagic disease virus (RHDV) into Australia and New Zealand from known starting stocks provides a unique opportunity to understand viral evolution and emergence. Within Australia, we revealed a major phylogenetic division between viruses sampled from the east and west of the country, with both regions likely seeded by viruses from South Australia. Despite their common origins, marked differences in evolutionary rates were observed between the Australian and New Zealand RHDV, which led to conflicting conclusions about population growth rates. An analysis of mutational patterns suggested that evolutionary rates have been elevated in the Australian viruses, at least in part due to the presence of low-fitness (deleterious) variants that have yet to be selectively purged.
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Dalmaris, Eleftheria, Cristina E. Ramalho, Pieter Poot, Erik J. Veneklaas und Margaret Byrne. „A climate change context for the decline of a foundation tree species in south-western Australia: insights from phylogeography and species distribution modelling“. Annals of Botany 116, Nr. 6 (07.04.2015): 941–52. http://dx.doi.org/10.1093/aob/mcv044.

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Dissertationen zum Thema "Phylogeography – Western Australia – South-West"

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Edwards, Danielle L. „Biogeography and speciation of southwestern Australian frogs“. University of Western Australia. School of Animal Biology, 2007. http://theses.library.uwa.edu.au/adt-WU2008.0058.

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[Truncated abstract] Southwestern Australia is a global biodiversity hotspot. The region contains a high number of endemic species, ranging from Gondwanan relicts to more recently evolved plant and animal species. Biogeographic models developed primarily for plants suggest a prominent role of Quaternary climatic fluctuations in the rampant speciation of endemic plants. Those models were not based on explicit spatial analysis of genetic structure, did not estimate divergence dates and may be a poor predictor of patterns in endemic vertebrates. Myobatrachid frogs have featured heavily in the limited investigations of the biogeography of the regions fauna. Myobatrachid frogs are diverse in southwestern Australia, and while we know they have speciated in situ, we know little about the temporal and spatial patterning of speciation events. In order to gain insight into the biogeographic history and potential speciation patterns of Myobatrachid frogs in the southwest I conducted a comparative phylogeography of four frog species spanning three life history strategies. I aimed to: 1) assess the biogeographic history of individual species, 2) determine where patterns of regional diversity exist using a comparative framework, 3) determine whether congruent patterns across species enable the development of explicit biogeographic hypotheses for frogs, and 4) compare patterns of diversity in plants with the models I developed for frogs. I conducted fine-scale intraspecific phylogeographies on four species. ... Geocrinia leai: deep divergences, coincident with late Miocene arid onset, divide this species into western and southeast coastal lineages, with a third only found within the Shannon-Gardner River catchments. Phylogeographic history within each lineage has been shaped by climatic fluctuations from the Pliocene through to the present. Arenophryne shows the first evidence of geological activity in speciation of a Shark Bay endemic. Divergence patterns between the High Rainfall and Southeast Coastal Provinces within C. georgiana are consistent with patterns between Litoria moorei and L. cyclorhynchus and plant biogeographic regions. Subdivision between drainage systems along the southern coast (in M. nichollsi, G. leai and the G. rosea species complex) reflect the relative importance of distinct catchments as refuges during arid maxima, similarly the northern Darling Escarpment is identified as a potential refugium (C. georgiana and G. leai). Divergences in Myobatrachid frogs are far older than those inferred for plants with the late Miocene apparently an important time for speciation of southwestern frogs. Speciation of Myobatrachids broadly relates to the onset of aridity in Australia in the late Miocene, with the exception of earlier/contemporaneous geological activity in Arenophryne. The origins of subsequent intraspecific phylogeographic structure are coincident with subsequent climatic fluctuations and correlated landscape evolution. Divergence within frogs in the forest system may be far older than the Pleistocene models developed for plants because of the heavy reliance on wet systems by relictual frog species persisting in the southwestern corner of Australia.
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Hoddell, Richard James. „A mtDNA study of aspects of the recent evolutionary history and phylogeographic structure of selected teleosts in coastal environments of south-western Australia“. Hoddell, Richard James (2003) A mtDNA study of aspects of the recent evolutionary history and phylogeographic structure of selected teleosts in coastal environments of south-western Australia. PhD thesis, Murdoch University, 2003. http://researchrepository.murdoch.edu.au/99/.

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At present, there is a general lack of information regarding the spatial genetic architecture and genetic diversity of estuarine and coastal freshwater fish in Australia or about the interacting intrinsic, extrinsic and historical influences responsible for sculpting these patterns. This thesis represented the first investigation of the phylogeographic structure and recent evolutionary histories of teleost fishes from the coastal and estuarine environments of south-western Australia, using the resolution afforded by mtDNA sequence data. Available evidence indicated that, to different degrees, these species have limited potential for dispersal amongst local assemblages from different water bodies. As this theoretically reduces the confounding effects of recent gene flow on extant genetic structure, these fishes were well suited to studying the influences of historical factors. Historical influences were expected to be particularly profound, given that these coastal environments underwent massive modifications during Late Quaternary eustatic fluctuations. The thesis consists of four major components, which explored different aspects of interspecific and intraspecific phylogeny and p hylogeograp hy of three teleost species, based on mtDNA control region and cytochrome b fragments. First, the relationship between the endemic, 'strictly estuarine' Leptatherina wallacei (Atherinidae) and the more widespread, 'estuarine and marine' 6. presbyteroides was examined, with a view to establishing whether 6. wallacei represents a monophyletic or polyphyletic lineage and whether this species was derived recently (i.e. in Holocene estuaries). Second, the phylogeographic structure and genetic diversity of L. wallacei were investigated and compared with data from L. presbyteroides, with a view to using this information to interpret the recent evolutionary histories of each congener. Third, the divergence between assemblages of L. wallacei inhabiting two isolated coastal lakes was used to estimate a maximal substitution rate for the control region, which was then used to infer general time frames for the divergence between the two Leptatherina species and between the major phylogeographic partitions within each species. Fourth, investigations were initiated into phylogeographic patterns and levels of genetic diversity within and among assemblages of Pseudogobius olorum (Gobiidae) from several coastal lakes and an estuary. Phylogenetic analyses indicated that the two Leptatherina species were characterised by exclusive and reciprocally-monophyletic lineages of aplotypes from both mtDNA regions, supporting the monophyletic origins of L. wallacei. Both 6. wallacei and 6. presbyteroides exhibited high levels of genetic diversity and extensive overall subdivision (e.g. Qsr = 0.691 and 0.644 respectively for control region data). There was a profound phylogeographic break in both species between all conspecific assemblages from the lower west coast (LWC phylogroup) and all those from the south coast (SC phylogroup), which suggested the influences of shared extrinsic and/or historical factors. There was limited genetic structuring within the two major phylogroups of either Leptatherina species, apparently reflecting recent connectivity amongst local assemblages, with subsequent fragmentation and insufficient time for lineage sorting. However, two major phylogeographic breaks distinguished monophyletic control region phylogroups of L. wallacei from the isolated coastal Lake Clifton and Lake Walyungup, consistent with their independent evolution following lacustrine entrapment during the Holocene. The divergence between these two isolated lacustrine assemblages of Leptatherina wallaceiformed the basis for an estimate of the maximal substitution rate of the control region. While these data were unable to provide a precise estimate of the actual rate of molecular evolution, all the evidence suggested that it was proceeding very rapidly. The maximal rate estimate of 172.3% lineage-' MY-' was among the fastest ever reported. Based on this rate, the two Leptatherina species diverged at least 1 SKya, thus rejecting a Holocene origin for L. wallacei. The divergence between the LWC and SC phylogroups of L. wallacei has been ongoing for at least GKya, while the equivalent divergence in L. presbyteroides has been ongoing for at least 11 Kya. As the time frames of these divergences were consistent with periods of massive environmental modifications associated with the end-Pleistocene fall in sea level and the HMT, it was likely that these factors have played important roles in sculpting the species' divergence and intra-specific genetic structure. Although useful in temporally scaling genetic divergences within and between the two Leptatherina species, wider application of this rate estimate to questions regarding other taxa was limited. For example, evident rate heterogeneity between the genera precluded its use with even the relatively closely-related atherinid Atherinosoma elongafa. Phylogeographic analyses identified high levels of genetic diversity and extensive genetic subdivision (e.g. st = 0.652 for control region) amongst an estuarine and several lacustrine assemblages of Pseudogobius olorum, although phylogeographic structure was shallower than in either Leptatherina species. There was increased divergence between three assemblages from the lower west coast and two from the south coast, consistent with the profound break evident in the Leptatherina. One lacustrine assemblage appeared to represent a distinct lineage and a preliminary maximal rate estimate (~61.4% lineage-1 MY-1) was calculated based on the minimum divergence of this assemblage from its nearest conspecifics. Although slower than the rate calculated for L. wallacei, this was still high for teleost fishes. Overall, this study indicated that historical environmental factors, especially those related to Quaternary eustatic changes, have played important roles in sculpting the phylogeography and evolution of three teleost species from south-western Australia. Moreover, as these species have differential dependencies on estuarine environments (is. 'strictly estuarine' vs 'estuarine and marine') and represented two different taxonomic groups (i.e. Atherinoidei and Gobioidei), historical environmental factors may have exerted similar influences on other coastal species in the region.
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au, rhoddell@central murdoch edu, und Richard James Hoddell. „A mtDNA study of aspects of the recent evolutionary history and phylogeographic structure of selected teleosts in coastal environments of south-western Australia“. Murdoch University, 2003. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20070831.162328.

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At present, there is a general lack of information regarding the spatial genetic architecture and genetic diversity of estuarine and coastal freshwater fish in Australia or about the interacting intrinsic, extrinsic and historical influences responsible for sculpting these patterns. This thesis represented the first investigation of the phylogeographic structure and recent evolutionary histories of teleost fishes from the coastal and estuarine environments of south-western Australia, using the resolution afforded by mtDNA sequence data. Available evidence indicated that, to different degrees, these species have limited potential for dispersal amongst local assemblages from different water bodies. As this theoretically reduces the confounding effects of recent gene flow on extant genetic structure, these fishes were well suited to studying the influences of historical factors. Historical influences were expected to be particularly profound, given that these coastal environments underwent massive modifications during Late Quaternary eustatic fluctuations. The thesis consists of four major components, which explored different aspects of interspecific and intraspecific phylogeny and p hylogeograp hy of three teleost species, based on mtDNA control region and cytochrome b fragments. First, the relationship between the endemic, 'strictly estuarine' Leptatherina wallacei (Atherinidae) and the more widespread, 'estuarine & marine' 6. presbyteroides was examined, with a view to establishing whether 6. wallacei represents a monophyletic or polyphyletic lineage and whether this species was derived recently (i.e. in Holocene estuaries). Second, the phylogeographic structure and genetic diversity of L. wallacei were investigated and compared with data from L. presbyteroides, with a view to using this information to interpret the recent evolutionary histories of each congener. Third, the divergence between assemblages of L. wallacei inhabiting two isolated coastal lakes was used to estimate a maximal substitution rate for the control region, which was then used to infer general time frames for the divergence between the two Leptatherina species and between the major phylogeographic partitions within each species. Fourth, investigations were initiated into phylogeographic patterns and levels of genetic diversity within and among assemblages of Pseudogobius olorum (Gobiidae) from several coastal lakes and an estuary. Phylogenetic analyses indicated that the two Leptatherina species were characterised by exclusive and reciprocally-monophyletic lineages of haplotypes from both mtDNA regions, supporting the monophyletic origins of L. wallacei. Both 6. wallacei and 6. presbyteroides exhibited high levels of genetic diversity and extensive overall subdivision (e.g. Qsr = 0.691 & 0.644 respectively for control region data). There was a profound phylogeographic break in both species between all conspecific assemblages from the lower west coast (LWC phylogroup) and all those from the south coast (SC phylogroup), which suggested the influences of shared extrinsic and/or historical factors. There was limited genetic structuring within the two major phylogroups of either Leptatherina species, apparently reflecting recent connectivity amongst local assemblages, with subsequent fragmentation and insufficient time for lineage sorting. However, two major phylogeographic breaks distinguished monophyletic control region phylogroups of L. wallacei from the isolated coastal Lake Clifton and Lake Walyungup, consistent with their independent evolution following lacustrine entrapment during the Holocene. The divergence between these two isolated lacustrine assemblages of Leptatherina wallaceiformed the basis for an estimate of the maximal substitution rate of the control region. While these data were unable to provide a precise estimate of the actual rate of molecular evolution, all the evidence suggested that it was proceeding very rapidly. The maximal rate estimate of 172.3% lineage-' MY-' was among the fastest ever reported. Based on this rate, the two Leptatherina species diverged at least 1 SKya, thus rejecting a Holocene origin for L. wallacei. The divergence between the LWC and SC phylogroups of L. wallacei has been ongoing for at least GKya, while the equivalent divergence in L. presbyteroides has been ongoing for at least 11 Kya. As the time frames of these divergences were consistent with periods of massive environmental modifications associated with the end-Pleistocene fall in sea level and the HMT, it was likely that these factors have played important roles in sculpting the species' divergence and intra-specific genetic structure. Although useful in temporally scaling genetic divergences within and between the two Leptatherina species, wider application of this rate estimate to questions regarding other taxa was limited. For example, evident rate heterogeneity between the genera precluded its use with even the relatively closely-related atherinid Atherinosoma elongafa. Phylogeographic analyses identified high levels of genetic diversity and extensive genetic subdivision (e.g. st = 0.652 for control region) amongst an estuarine and several lacustrine assemblages of Pseudogobius olorum, although phylogeographic structure was shallower than in either Leptatherina species. There was increased divergence between three assemblages from the lower west coast and two from the south coast, consistent with the profound break evident in the Leptatherina. One lacustrine assemblage appeared to represent a distinct lineage and a preliminary maximal rate estimate (~61.4% lineage-1 MY-1) was calculated based on the minimum divergence of this assemblage from its nearest conspecifics. Although slower than the rate calculated for L. wallacei, this was still high for teleost fishes. Overall, this study indicated that historical environmental factors, especially those related to Quaternary eustatic changes, have played important roles in sculpting the phylogeography and evolution of three teleost species from south-western Australia. Moreover, as these species have differential dependencies on estuarine environments (is. 'strictly estuarine' vs 'estuarine & marine') and represented two different taxonomic groups (i.e. Atherinoidei & Gobioidei), historical environmental factors may have exerted similar influences on other coastal species in the region.
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Estrada, Roldan Beatriz Elena. „Neotectonic and palaeoseismological studies in the southwest of Western Australia“. University of Western Australia. School of Earth and Environment, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0061.

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[Truncated abstract] The southwest of Western Australia is an intraplate area classified as a stable continental region. It comprises predominantly Archaean and Proterozoic geology and has generally subdued topography. The region currently experiences significant seismicity in the Southwest Seismic Zone (SWSZ), which is one of the most seismically active areas in Australia and is thought to represent the highest seismic hazard of the region. In recent years, numerous scarps, potentially related to large palaeoearthquakes have been recognised not only within the SWSZ, but also in a broader region of the southwest of Australia. Palaeoseismological investigations of two of these scarps, the Dumbleyung and the Lort River scarps, confirm their association with surface-rupturing palaeoearthquakes and indicate events with likely maximum magnitudes of ~Mw 7.0 on faults of low to medium slip rates. Two trenches across the Dumbleyung Fault scarp revealed a thrust fault in alluvial sediments with two associated earthquakes in the last ca 24-60 ka. A possible Holocene age was recognised for the last recorded earthquake event exposed in these trenches. Two trenches across the Lort River Scarp show that this feature results from thrust faulting in the weathered gneissic country rock. These trenches exposed evidence of two events in the last ca 35 ka, with a likely late Pleistocene age for the last earthquake. On both sites, the earthquakes are interpreted as associated with the last phase of fault activity, which was likely been preceded by a long period of quiescence. Assessment of the earthquake hazard associated with large earthquakes at the Dumbleyung and Lort River Faults resulted in calculated peak ground accelerations of up to 2 g in the near-fault fields. Such earthquakes would significantly affect nearby towns such as Dumbleyung, Wagin, Katanning, and Esperance, but they are unlikely to cause any significant damage in Perth. The palaeoseismological investigations show that the earthquake activity in the southwest of Western Australia is not only confined to the SWSZ, as it has been considered in previous assessments of the seismic hazard, but that there is also potential for strong earthquakes across much of the region. The seismicity in the southwest of Western Australia appears to be transient and migratory. This is suggested by the lack of local relief associated with places of current seismicity and fault scarps, the widespread distribution of the fault scarps across the region, the increase in seismicity in the SWSZ following strong recent events, and the apparent long periods of earthquake recurrence at fault sites. Accordingly, the current seismicity in the SWSZ is inferred to be transient and probably associated with stress changes produced by the recent earthquakes. '...' This uplift could be associated with dynamic topography effects resulting from processes along the plate margins. The uplift is probably enhanced by a flexural response of the lithosphere to local differential loads and density contrast along the southern margin, a mechanism that may also help explain the occurrence of some earthquake activity. The results from this study, complemented by additional palaeoseismological studies must be included in future probabilistic assessments of the seismic hazard of the southwest of Western Australia.
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Horsnell, Tara Kathleen. „Quantifying thresholds for native vegetation to salinity and waterlogging for the design of direct conservation approaches“. University of Western Australia. School of Environmental Systems Engineering, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0082.

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A field-based project was undertaken to develop and test a mechanism which would allow for the correlation of the health of vegetation surrounding playa lakes in south-west Australia with the natural variation in salinity and waterlogging that occurs spatially and temporally in natural systems. The study was designed to determine threshold ranges of vegetation communities using moderately extensive data over short temporal periods which will guide the design of potential engineering solutions that manipulate hydrological regimes to ultimately conserve and protect native vegetation. A pair of playa lake ecosystems, surrounded by primary production land, was modelled with hydro-geological data collected from March 2006 to March 2007. The data was used to determine the hydroperiods of vegetation communities fringing playa lakes and provide insight into the areas and species that are most affected by extreme rainfall events which are hypothesised to have a significant, rapid deleterious effect on the ecosystems. The methodology was multi-faceted and included; a detailed topographical survey; vegetation surveys; hydrological and hydro-geological monitoring over a 12 month period. 4 The hydro-geological data and vegetation data was linked with the topographical survey at a high resolution for spatial analysis in a Geographic Information System (GIS) to determine the degree of waterlogging experienced by vegetation communities over the monitoring period. The study has found that the spatial and temporal variability of hydroperiods has been reduced by rising groundwater levels, a result of extensive clearing of native vegetation. Consequently populations are becoming extinct locally resulting in a shift in community composition. Extreme summer rainfall events also have a significant impact on the health of vegetation communities by increasing the duration of waterlogging over an annual cycle and in some areas expanding the littoral zone. Vegetation is most degraded at lower positions in the landscape where communities are becoming less diverse and dominated by salt tolerant halophytic species as a result of altered hydrological regimes. Some species appear to be able to tolerate groundwater depths of less than 2.0 m from the surface, however there are thresholds related to the duration at which groundwater is maintained at this depth. Potential engineering solutions include groundwater pumping and diverting water through drains to maintain sustainable hydroperiods for vegetation in areas with conservation value. The effectiveness and efficiency of the engineering solutions can be maximised by quantifying thresholds for vegetation that include sustainable durations of waterlogging. The study has quantified tolerance ranges to salinity and waterlogging with data collected over 12 months but species may be experiencing a transition period where they have 5 sustained irreversible damage that will result in their eventual mortality. With long-term monitoring, the methodology developed and tested in the study can be used to quantify the long-term tolerance ranges that are important for the application of conservation approaches that include engineering solutions.
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Callow, John Nikolaus. „River response to land clearing and landscape salinisation in southwestern Australia“. University of Western Australia. School of Earth and Geographical Sciences, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0085.

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[Truncated abstract] Land clearing is known to increase runoff, and in many dryland landscapes is also associated with rising saline watertables, causing increased stream salinity and degrading riparian vegetation. The limited understanding of how river morphology responds to these changes and the potential for vegetation-based strategies to offer river management options under these conditions, has prompted this research. In southwestern Australia the severity of salinity and recent nature of land clearing provides an appropriate setting to investigate river response. A data-based, multidisciplinary methodology was applied to determine how land clearing and landscape salinisation has altered landscape sensitivity through changes in erosive potential, system connectivity and material threshold mechanisms, and how these affect patterns of river response. The study investigated the responses of morphologically similar reaches across fifty two study sites in the Kent River and Dalyup River catchments, in the south coastal rivers region of Western Australia. Land clearing was found to have significantly altered the hydrologic regime and erosive potential in both frequency and magnitude, with flow becoming more perennial, and increased annual discharge, flood peaks and bankfull flow frequency. While sediment transport rates have also increased since land clearing, they remain low on a global scale. Human response to a reduced rainfall regime and related water security pressures has caused large hillslope areas to be decoupled from the main channels by bank and farm dam construction, and have reduced downstream transmission of change. ... By contrast, steeper-sloped mid-catchment areas with minimal vegetation degradation caused by salinity are associated with higher erosive potential. A more erosive response is observed in these reaches where floodplains have been cleared for agricultural purposes. A conceptual model of vegetation growth across the salinity gradient observed in the study catchments was developed, and applied to selected river styles to assess the potential that vegetation-based strategies offer for river management. This work identifies the unsuitability of river restoration strategies, but the potential for river restoration or remediation in a saline landscape. Hydraulic modelling demonstrated that river rehabilitation strategies such as improving the vegetation condition of the riparian buffer using native or commercial species on areas elevated above saline flow can stabilise reaches. For river styles in wide and flat valleys, there is limited potential for vegetation-based river rehabilitation under the current salinity gradient. Field observation and modelling suggest that river remediation may offer geomorphic management options in salt-affected reaches through channelisation to lower watertables, and further research on this is warranted. This work found a consistent response for river styles across the two study catchments. Based on the understanding of river response and the potential for vegetation-based river management for each style, this research offers a regional-scale tool for river management in a saline landscape.
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Sounness, Marcus Neil. „Alternative grazing systems and pasture types for the South West of Western Australia : a bio-economic analysis“. University of Western Australia. School of Agricultural and Resource Economics, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0054.

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Alternative grazing systems and pasture types for wool production in the south west of Western Australia were analysed using bio-economic modelling techniques in order to determine their relative productivity and profitability. After reviewing the experimental and modelling literature on perennial pastures and grazing systems, seven case studies of farmers were conducted in order to investigate the practical application of innovative grazing systems and use of perennial pastures. Together these case studies provided information for identifying relevant variables and for calibrating the modelling work which followed. The core of the work lies in a bio-economic model for investigating the comparative value of the three grazing systems and two pasture families mentioned above. A baseline scenario using currently available and reliable scientific data provides baseline results, after which a number of sensitivity analyses provide further insights using variations of four key parameters: persistence, heterogeneity, water soluble carbohydrates, and increased losses. Results show that perennial pastures are in the studied region more profitable than annual pastures. Under current baseline conditions, continuous grazing with perennial pastures is the most profitable enterprise, but this superiority is not robust under parameter variations defined by other scenarios. The more robust solution in terms of enterprise profitability is cell grazing with perennial pastures. The results indicate that intensive grazing systems such as cell grazing have the potential to substantially increase the profitability of grazing operations on perennial pasture. This result is an encouraging one in light of its implications for water uptake and salinity control. It means that economics and land care can go hand in hand, rather than be competitive. It is to be noted that it is the choice of the grazing system in combination with the pasture species, rather then the pasture species itself, that allows for such complementarity between economics and sustainable land use. This research shows that if farmers adopt practices such as cell grazing they may be able to increase the area that they can profitably plant to perennial pasture thus reducing the impacts of dryland salinity. This finding is consistent with the findings of the case studies where the farmers perceived that, provided grazing was planned, increasing the intensity of their grazing management and the perenniallity of their pastures would result in an increase in the profitability of their grazing operation. As a result this research helps to bridge a gap which has existed in this area of research, between the results of scientific research and those reported in practice.
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Collins, Margaret Thora. „Factors affecting the recovery of orchids in a post-mining landscape“. University of Western Australia. School of Earth and Geographical Sciences, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0022.

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[Truncated abstract] Currently, Alcoa World Alumina Australia (Alcoa) mines and undertakes procedures to rehabilitate approximately 550 ha of jarrah forest each year at two open-cut bauxite mines in South-West Western Australia. Alcoa aims to establish a self-sustaining jarrah forest ecosystem that maintains the functions of the landscape prior to mining, including biodiversity, on areas that have been mined for bauxite. Indigenous terrestrial orchids form a significant proportion of the indigenous geophytic plant species that either fail to colonise rehabilitated areas or do so very slowly. Terrestrial orchids are considered to be particularly sensitive to competition from weeds and disturbance, which combined with the obligate nature of the orchid-mycorrhizal fungus association suggests that orchids would colonise rehabilitation areas only when both microhabitat sites and soil microflora have established. Occurrence of certain orchids may therefore be expected to be useful as indicators of ecosystem health, the success of vegetation establishment and the recovery of edaphic conditions suitable for orchid mycorrhizal fungi. Vegetation surveys were undertaken to compare orchid species richness and population size of a chrono-sequence of rehabilitation areas with adjacent unmined forest. ... Orchid taxa present in each vegetation assemblage were generally not exclusive to these assemblages, with the following broad exclusions: D. bracteata was found only in species assemblages associated with rehabilitation areas; and Eriochilus sp. and T. crinita were found only in species assemblages associated with unmined forest. No single orchid species appears to be an indicator of ecosystem recovery. However, the presence of populations of C. flava, P. sp. crinkled leaf (G.J.Keighery 13426) or P. recurva in combination with the absence of the disturbance opportunist orchid taxa D. bracteata and M. media appears to be a measure of the maturity of the rehabilitation vegetation. Orchid species richness and clonal orchid population size were correlated with changes in vegetation structure, but apart from the absence of orchids in 1 year old rehabilitation areas, these orchid population characteristics did not show any direct relationship with rehabilitation age or vegetation maturity. Only two orchid taxa appeared to have potential as indicators of vegetation characteristics: T. crinita as an indicator of undisturbed jarrah forest; and D. bracteata as an indicator of disturbed ecosystems. The results of this study suggest that most jarrah forest orchid taxa will readily colonise the post bauxite mining landscape, but that the unassisted colonisation by recalcitrant orchid taxa may be a prolonged process. It is recommended that field-based transplantation and/or seeding trials be undertaken with these recalcitrant taxa to determine if these procedures will enhance recruitment. The results of this work have applications not only in the management of post-mining landscapes but also in vegetation monitoring and conservation work in Western Australia and elsewhere.
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Szota, Christopher. „Root morphology, photosynthesis, water relations and development of jarrah (Eucalyptus marginata) in response to soil constraints at restores bauxite mines in south-western Australia“. University of Western Australia. School of Plant Biology, 2009. http://theses.library.uwa.edu.au/adt-WU2010.0058.

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Bauxite mining is a major activity in the jarrah (Eucalyptus marginata Donn ex Sm.) forest of south-western Australia. After mining, poor tree growth can occur in some areas. This thesis aimed to determine whether soil constraints, including reduced depth and compaction, were responsible for poor tree growth at low-quality restored bauxite mines. In particular, this study determined the response of jarrah root morphology, leaf-scale physiology and growth/development to soil constraints at two contrasting (low-quality and high-quality) restored bauxite-mine sites. Jarrah root excavations at a low-quality restored site revealed that deep-ripping equipment failed to penetrate the cemented lateritic subsoil, causing coarse roots to be restricted to the top 0.5 m of the soil profile, resulting in fewer and smaller jarrah trees. An adjacent area within the same mine pit (high-quality site) had a kaolinitic clay subsoil, which coarse roots were able to penetrate to the average ripping depth of 1.5 m. Impenetrable subsoil prevented development of taproots at the low-quality site, with trees instead producing multiple lateral and sinker roots. Trees in riplines, made by deep-ripping, at the high-quality site accessed the subsoil via a major taproot, while those on crests developed large lateral and sinker roots. Bauxite mining is a major activity in the jarrah (Eucalyptus marginata Donn ex Sm.) forest of south-western Australia. After mining, poor tree growth can occur in some areas. This thesis aimed to determine whether soil constraints, including reduced depth and compaction, were responsible for poor tree growth at low-quality restored bauxite mines. In particular, this study determined the response of jarrah root morphology, leaf-scale physiology and growth/development to soil constraints at two contrasting (low-quality and high-quality) restored bauxite-mine sites. Jarrah root excavations at a low-quality restored site revealed that deep-ripping equipment failed to penetrate the cemented lateritic subsoil, causing coarse roots to be restricted to the top 0.5 m of the soil profile, resulting in fewer and smaller jarrah trees. An adjacent area within the same mine pit (high-quality site) had a kaolinitic clay subsoil, which coarse roots were able to penetrate to the average ripping depth of 1.5 m. Impenetrable subsoil prevented development of taproots at the low-quality site, with trees instead producing multiple lateral and sinker roots. Trees in riplines, made by deep-ripping, at the high-quality site accessed the subsoil via a major taproot, while those on crests developed large lateral and sinker roots.
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my, marina@umt edu, und Marina Hassan. „Parasites of native and exotic freshwater fishes in the south-west of Western Australia“. Murdoch University, 2008. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20090720.141418.

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Fewer than 200 fish species are found in freshwater habitats in Australia, of which 144 are confined exclusively to freshwater. At least 22 species of exotic freshwater fish have been introduced into Australia, and 19 of these have established self-sustaining populations. However, the parasite fauna of both native and exotic freshwater fishes in Australia is poorly known. This is particularly the case in the south-west of Western Australia, where there have been no previous comprehensive studies of the parasites of 14 native species and nine or more exotic species of fish found in freshwater habitats. This study represents a survey of the parasites of freshwater fishes in the South West Coast Drainage Division and reports 44 putative species of parasites in 1429 individual fishes of 18 different species (12 native and six exotic) from 29 locations. Parasites were found in 327 (22.88%) fishes, and of the infected fishes, 200 (61.16%) were infected with only one species of parasite and 127 (38.84%) were infected with two or more species of parasites. For helminth and arthropod parasites, which were more comprehensively surveyed than protozoan and myxozoans, I found 37 species compared to 77 species found in a recent study of fishes from the East Coast Drainage Division. The present study demonstrated that parasitic infection was significantly more common in native fish species (mean prevalence of infection with any species of parasite = 0.36 ± 0.09) than in exotic fish species (0.01 ± 0.12). Parasites were found in all native fish species, but in only two exotic fish species that were examined. Parasite regional and component community diversity were estimated by species richness (the number of species, S) and by an index of taxonomic diversity (HT). Both parasite species richness and parasite taxonomic diversity were significantly greater in native fish species (mean S = 10.5 ± 2.3; mean HT = 1.19 ± 0.14) than in exotic fish species (mean S = 1.6 ± 3.3; mean HT = 0.27 ± 0.20). These relationships were consistent over all geographic locations that were sampled. The reduced parasite load of exotic species compared to native species has been previous reported across a wide range of taxa. It is thought to arise partly because founding populations of hosts have a low probability of harbouring the species’ total parasite fauna, and partly because parasites that infect introduced exotic species may not be able to maintain their life cycle in the new environment. It has been suggested that a reduced parasite load increases the competitive ability of exotic species compared to native species (the parasite release hypothesis) and this may partly explain the abundance and apparent competitive success of exotic over native species of freshwater fish in the South West Coast Drainage Division. For native species of fish, there were major differences among species in both prevalence of parasitic infection and parasite community diversity, but this variation was not related to fish size, whether the fish were primarily freshwater or primarily estuarine, or whether they were primarily demersal or pelagic. In this study, I report two new parasites in south western Australian waters. Both are copepod parasites; Lernaea cyprinacea and a new species of Dermoergasilus. The Dermoergasilus appears to be native to the south-west of Western Australia and has been described as Dermoergasilus westernensis. It differs from previously described species in the genus principally by the armature of the legs. This new species was found on the gills of freshwater cobbler, Tandanus bostocki and western minnow, Galaxias occidentalis in two different river systems. Lernaea cyprinacea is an introduced parasitic copepod found on the skin and gills of freshwater fishes in many areas of the world. The parasite has not previously been reported in Western Australia. We found infestations of L. cyprinacea on four native fish species (G. occidentalis; Edelia vittata; Bostockia porosa; T. bostocki) and three introduced fish species (Carassius auratus; Gambusia holbrooki; Phalloceros caudimaculatus) at two localities in the Canning River, in the south-west of Western Australia. The parasite has the potential to have serious pathogenic effects on native fish species, although it appears to be currently localised to a small section of the Canning River. Over all localities from which fishes were sampled in the present study, the proportion of native freshwater fishes with parasitic infections and the component community diversity of the parasite fauna of native fishes were both negatively related to habitat disturbance, in particular to a suite of factors (river regulation, loss of riparian vegetation, eutrophication and presence of exotic fish species) that indicate increased human usage of the river and surrounding environment. The reduced parasite load and diversity in native fishes from south-west rivers with greater human usage was due principally to the loss of a number of species of trematode, cestode and nematode endoparasites which use fishes as intermediate hosts. Other studies have also found that endoparasites with complex life cycles are most likely to be adversely affected by environmental changes, presumably because any environmental changes which impact on either free-living parasite stages or on any of the hosts in the complex train of parasite transmission will reduce parasite population size and may cause local extinction of the parasite species. The most heavily infected species of native freshwater fish in the South West Coast Drainage Division was T. bostocki with 96% of all individuals containing at least one species of parasite. As with most freshwater fishes of south-west Australia, T. bostocki is limited in its distribution to waterways with relatively low salinity. The degree of parasitism and histopathology of internal and external organs in T. bostocki from the Blackwood River was examined over a period of rapid, seasonal changes in water salinity. As salinity increased, the infracommunity richness and prevalence of ectoparasites on the skin of fishes decreased, while the infracommunity richness and prevalence of endoparasites increased. This was associated with a decrease in histopathological lesion scores in the skin and an increase in histopathological lesion scores in internal organs, particularly the intestine. I hypothesise that the seasonal spike in salinity had two contrasting effects on parasitic infections of T. bostocki. Firstly, it increased the mortality rate of parasites directly exposed to water, leading to a decrease in ectoparasitic infection and associated pathology. Secondly, it suppressed immune function in fish, leading to a decreased mortality rate of parasites not directly exposed to water and a more severe pathological response to endoparasitism.
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Bücher zum Thema "Phylogeography – Western Australia – South-West"

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Croft, Brenda L. South West Central: Indigenous art from south Western Australia 1833-2002. Perth, W.A: Art Gallery of Western Australia, 2003.

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Storr, G. M. Birds of the South-west Division of Western Australia. Perth, W.A: Western Australian Museum, 1991.

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Lois, Tilbrook, und Art Gallery of Western Australia., Hrsg. Ffarington's folio: South West Australia, 1843-1847. Perth, W.A: Art Gallery of Western Australia, 1986.

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Bindon, Peter, und Ross Chadwick. A Nyoongar wordlist from the south-west of Western Australia. Welshpool, Western Australia: Western Australian Museum, 2011.

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Mayer, Xanthe. Stream salinity status and trends in south-west Western Australia. East Perth, W.A: Natural Resource Management and Salinity Division, Dept. of Environment, 2005.

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Supply, Western Australia Steering Committee for Research on LandUse and Water. Stream salinity and its reclamation in south-west Western Australia. Leederville, WA: Water Authority of Western Australia, Water Resources Directorate, 1989.

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Western Australia. South West Development Authority. Aerodrome Co-ordinating Committee. Report of the South West Aerodrome Co-ordinating Committee. [Bunbury]: South West Development Authority, 1991.

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Stanton, John E. Nyungar landscapes: Aboriginal artists of the South-West : the heritage of Carrolup, Western Australia. [Nedlands, W.A.]: University of Western Australia, Berndt Museum of Anthropology, 1992.

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Griffiths, Kevn. A field guide to the larger fungi of the Darling Scarp & south west of Western Australia. [Western Australia?]: K. Griffiths, 1985.

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Haebich, Anna. For their own good: Aborigines and government in the south west of Western Australia, 1900-1940. 2. Aufl. Nedlands, W.A: Published by the University of Western Australia Press for the Charles and Joy Staples South West Region Publications Fund, 1992.

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Buchteile zum Thema "Phylogeography – Western Australia – South-West"

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Selwood, John, und Matthew Tonts. „10. Recreational Second Homes in the South West of Western Australia“. In Tourism, Mobility and Second Homes, herausgegeben von C. Michael Hall und Dieter K. Müller, 149–61. Bristol, Blue Ridge Summit: Multilingual Matters, 2004. http://dx.doi.org/10.21832/9781873150825-012.

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Abbott, Ian, und Neil Burrows. „Monitoring biodiversity in jarrah forest in south-west Western Australia: the Forestcheck initiative“. In Conservation of Australia's Forest Fauna, 947–58. P.O. Box 20, Mosman NSW 2088: Royal Zoological Society of New South Wales, 2004. http://dx.doi.org/10.7882/fs.2004.947.

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Craig, Michael D. „The value of unlogged buffers for vulnerable bird species in the jarrah forest of south-west Western Australia“. In Conservation of Australia's Forest Fauna, 774–82. P.O. Box 20, Mosman NSW 2088: Royal Zoological Society of New South Wales, 2004. http://dx.doi.org/10.7882/fs.2004.047.

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Gaynor, Andrea. „Shifting Baselines or Shifting Currents? An Environmental History of Fish and Fishing in the South-West Capes Region of Western Australia“. In Historical Perspectives of Fisheries Exploitation in the Indo-Pacific, 231–50. Dordrecht: Springer Netherlands, 2014. http://dx.doi.org/10.1007/978-94-017-8727-7_12.

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Williams, Matthew R. „Habitat resources, remnant vegetation condition and area determine distribution patterns and abundance of butterflies and day-flying moths in a fragmented urban landscape, south-west Western Australia“. In Lepidoptera Conservation in a Changing World, 271–88. Dordrecht: Springer Netherlands, 2010. http://dx.doi.org/10.1007/978-94-007-1442-7_25.

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„The sustainability assessment of the South West Yarragadee Water Supply Development in Western Australia“. In Sustainability Assessment, 110–23. Routledge, 2016. http://dx.doi.org/10.4324/9781315754048-13.

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Carlen, Joe. „Western Europe and a “New World” of Profit“. In A Brief History of Entrepreneurship. Columbia University Press, 2016. http://dx.doi.org/10.7312/columbia/9780231173049.003.0007.

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The extraordinary impact of the heyday of European colonialism (16th to 19th centuries) is unquestionable: Of the four continents that were relatively unknown to the West prior to colonialism, three—Australia, North America, and South America—were entirely transformed in the image of their colonizers. As this chapter demonstrates, not only were European entrepreneurs the primary beneficiaries of colonialism but, in many vital respects, their countries’ settlement of “new” territories would not have been possible without entrepreneurial labor and capital.
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Wyche, Stephen, Yongjun Lu und Michael T. D. Wingate. „Evidence of Hadean to Paleoarchean Crust in the Youanmi and South West Terranes, and Eastern Goldfields Superterrane of the Yilgarn Craton, Western Australia“. In Earth's Oldest Rocks, 279–92. Elsevier, 2019. http://dx.doi.org/10.1016/b978-0-444-63901-1.00013-7.

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Pliaskin, Alex. „The BIZEWEST Portal“. In Electronic Business, 1396–400. IGI Global, 2009. http://dx.doi.org/10.4018/978-1-60566-056-1.ch085.

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In June 2000, the Western Region Economic Development Organisation (WREDO), a notfor- profit organisation sponsored by the six municipalities that make up the western region of Melbourne, received a state government grant for a project to set up a business-to-business portal. The project was to create a “horizontal portal”—BIZEWEST—that would enable small to medium enterprises (SMEs) in Melbourne’s west to engage in an increased number of e-commerce transactions with each other. The western region of Melbourne contains around 20,000 businesses, and is regarded as the manufacturing, transport, and distribution hub of South-eastern Australia (Tatnall, Burgess, & Singh, 2004). Traditionally, this region had encompassed much of the industry in metropolitan Melbourne.
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Rivas, Jesús A. „The Origin of the Mystery“. In Anaconda, 222–32. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780199732876.003.0009.

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This chapter traces the paleo-history of South America to tackle evolutionary questions about anacondas. Going back in history 150 million years ago, the current continents of South America and Africa were joined in a single mega-continent that also included current Australia and Antarctic. In the northern part of this continent (current South America and Africa) was a large river that started roughly where the current Congo River starts and drained the continent out of what is currently western Ecuador. Approximately 110 million years ago, South America separated from Africa and drifted west. The continent was drained by the paleo-Amazon. As South America drifted west, it collided with the Nazca plate in the eastern Pacific. As the two landmasses moved against each other, the Nazca plate subsided under South America, pushing up the western border of the latter, giving rise to the Andes. The creation of the Andes would result in the eventual closing of the drainage of the paleo-Amazon into the Pacific Ocean. The chapter looks at the significance of this paleo-history to the evolution of anacondas. It seems like the conditions in the paleo-history of the continent of constant flooding were not all that different from the conditions that anacondas encounter currently in the llanos.
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Konferenzberichte zum Thema "Phylogeography – Western Australia – South-West"

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„Initial analysis of fire weather characteristics between south-east Australia and south-west of Western Australia“. In 20th International Congress on Modelling and Simulation (MODSIM2013). Modelling and Simulation Society of Australia and New Zealand (MSSANZ), Inc., 2013. http://dx.doi.org/10.36334/modsim.2013.m1.lin.

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Langhi, L., Y. Zhang, B. Ciftci, C. Delle Piane, J. Strand, D. Dewhurst, L. Stalker und K. Michael. „Preliminary Analysis of Containment Integrity for Geological Storage of CO2 at the South West Hub Project, Western Australia“. In Fourth International Conference on Fault and Top Seals. Netherlands: EAGE Publications BV, 2015. http://dx.doi.org/10.3997/2214-4609.201414052.

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„Integrated surface water and groundwater modelling to support the Murray Drainage and Water Management Plan, south-west Western Australia“. In 19th International Congress on Modelling and Simulation. Modelling and Simulation Society of Australia and New Zealand (MSSANZ), Inc., 2011. http://dx.doi.org/10.36334/modsim.2011.i10.hall.

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„Coupled surface water and groundwater model development and calibration using MIKE SHE for the Greater Bunbury region in south-west Western Australia“. In 22nd International Congress on Modelling and Simulation. Modelling and Simulation Society of Australia and New Zealand (MSSANZ), Inc., 2017. http://dx.doi.org/10.36334/modsim.2017.l9.alam.

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