Inland salt lakes of the arid and semi-arid zones of Western Australia are unique systems. An unpredictable rainfall pattern and a transient water regime ensure these lakes remain dry for much of the year. Lake Yindarlgooda in the Eastern Goldfields of Western Australia is a typical inland salt lake that has been subjected to additional stresses. This thesis is the outcome of investigations conducted on the lake from 2001 to 2003. Emphasis is on the limnology and biota of the lake, including an adjacent wetland, and impacts on the aquatic ecosystems caused predominantly by mining. Lake Yindarlgooda is a large, shallow hypersaline lake situated on the Yindarlgooda Palaeoriver. It is sodium chloride dominated and has naturally high background levels of nickel. Sites impacted by the leaching of hypersaline decant water from a leach residue storage facility (LRSF) were differentiated from control sites using multivariate statistics. Salinity was found to be a major determinant in the structure of the biological communities in the lake systems. / Different biotic communities with low taxonomic diversity were recorded in Lake Yindarlgooda and Swan Refuge, a nearby hyposaline clay pan. The benthic microbial communities were dominated by halotolerant diatoms, notably Amphora coffeaeformis, Navicula incertata and Hantzschia baltica. Variation in the diatom assemblages between the playa sites and the clay pan were noted, influenced by habitat type and salinity. Within Lake Yindarlgooda, the diatom assemblages in the control and impact sites were found to be similar. A narrow salinity spectrum dictated the taxa present. Many of the benthic diatoms collected during the dry phase were encysted, having entered dormancy. The invertebrate fauna in Lake Yindarlgooda and Swan Refuge belonged to the Crustacea. A larger percentage of hyposaline invertebrate taxa were recorded from Swan Refuge, while those in Lake Yindarlgooda were typically halotolerant species. The Ostracoda showed the greatest diversity and their abundance was higher in the southern control sites while the Anostracan, Parartemia sp., dominated the northern impact sites of the playa. / The riparian zone of Lake Yindarlgooda supported a diverse plant community, dominated by the Chenopodiaceae. The marginal vegetation communities along the shores of Lake Yindarlgooda were found to be similar, indicating habitat homeogeneity. Within the riparian zone both biological and physical soil crusts occupied large areas not inhabited by vascular plants. The biological soil crust identified was composed of an association between the filamentous cyanobacterium Microcoleus sp. and a moss species (Musci). Both biological and physical soil crusts were found to have functional roles in stabilising the surrounding low dunes. The soil crusts in the northern control sites were badly degraded as a result of trampling by livestock, while those in the southern control sites were protected and were intact. Only one Parartemia species was found to inhabit Lake Yindarlgooda, Parartemia n. sp. d. It was collected in salinities ranging from 50 to 140 g L-1. The population appeared to be oviparous, recruitment mostly from resting eggs. The male to female ratios varied between sites, as did the number of juveniles compared to the adults. The northern impact sites had a more mature Parartemia population than the southern control sites and appeared to have undergone a second recruitment. Examination of the surface sediment found a well established Parartemia “egg bank” in the northern impact sites with egg numbers much higher than in the southern control sites. / The ultrastructure of the Parartemia resting egg was identical to that of Artemia. Differences in the external features and internal structure of the resting egg of Parartemia n sp. d and Parartemia n. sp g from Lake Miranda, another saline lake, were identified. This study showed morphological variation of the egg within Parartemia, a finding not previously recorded. Rehydration trials on the Parartemia egg bank indicated that the increase in sediment salinity from the LRSF had a negative effect on the hatching of the resting eggs. In salinities above 60 mS cm-1 hatching was less successful. The conditions provided in the trials were similar to those in Lake Yindarlgooda. The hatching technique was repeated on sediment from Lake Miranda with similar results. These trials were considered a valuable monitoring tool in the assessment of impacts on the biota of temporary lakes in the absence of water. This study demonstrated that in the absence of water the egg and spore/seed bank can be used as a proxy for monitoring temporary lakes. It was also found to be valuable in understanding the distribution and diversity of the biotic communities in Lake Yindarlgooda. This study provides the first integrated reference information on a Western Australian inland salt lake against which any future impact may be assessed.

A Floresta Nacional de Carajás é uma unidade de conservação federal localizada no sudeste da Amazônia, região Norte do Brasil. Juntamente com outras cinco áreas formam o Mosaico de Carajás com um contínuo de 1.307.000 hectares de área protegida. As principais fitofisionomias presentes no interior da unidade são a Floresta Ombrófila Densa e a Savana Metalófila. A unidade abriga a maior província mineral do mundo. A atividade de mineração promove diferentes impactos sobre a fauna principalmente através da modificação de paisagem originada pela supressão vegetal. O objetivo desse trabalho foi estudar a composição da comunidade de mamíferos de médio e grande porte através do levantamento de informações sobre a riqueza, a abundância e as diferenças entre a composição da mastofauna nas fitofisionomias de Savana Metalófila e Floresta Ombrófila Densa e suas alterações ocasionadas pelo impacto da mineração. Foram realizadas quatro campanhas em 19 trilhas que se distribuíram em áreas de Savana Metalófila e Floresta Ombrófila Densa impactadas e controle. A metodologia utilizada foi de transecção linear e armadilhamento fotográfico com um esforço total empregado de 432 km e 85.920 horas, para cada um dos métodos, respectivamente. A comunidade de mastofauna de médio e grande porte apresentou 43 espécies distribuídas em oito ordens, com um aumento de 41% de novos registros para a região. A composição da comunidade de mastofauna apresentou diferenças quanto a riqueza e a abundância das espécies nas duas fitofisionomias e quanto ao efeito do impacto da mineração. O presente trabalho trouxe avanços em relação à lista de espécies de mamíferos de médio e grande porte e aumentou o conhecimento a respeito da composição desta fauna em ambientes de floresta e de savana na Floresta Nacional de Carajás. Trouxe informações acerca dos impactos sobre a mastofauna e identificou importantes sensibilidades de algumas espécies frente à mineração, contribuindo para a busca do equilíbrio entre a mineração e a conservação. / The National Forest of Carajás is a federal conservation unit located in the southeast of the Amazon, northern Brazil. Together with other five areas make up the mosaic of Carajás with a continuum of 1.307 million hectares of protected area. The main vegetation types present within the unit are the Dense Montane Forest and Savana Metalófila. The unit houses the largest mineral reserves in the world. Mining activity promotes different impacts on fauna mainly by alteration of the landscape caused by vegetation removal and stacking sterile. The aim of this work was to study the composition of the mammal community of medium and large through the collection of information about richness, abundance and differences between vegetation types in the mammalian species composition of Savana Metalófila and Dense Montane Forest and its changes caused by the impact. Were conducted four campaigns and 19 tracks that were distributed in areas of Savana Metalófila and Dense Montane Forest impacted and control. The methodology used was to linetransect and camera trapping employee with a total effort of 432 km and 85.920 hours for each method, respectively. The mammal community of medium and large showed 43 species in eight orders, showing an increase of 41% of new registrations for the region. The community composition of mammal species show differences in richness and abundance of species in two vegetation types and the effect of the impact of mining. This work has brought about improvements to the list of mammalian species of medium and large size and increased knowledge about the composition of this fauna in environments of forest and savanna in the Carajás National Forest. Brought information about the impacts on mammals and identified important sensitivities of some species facing the mining, contributing to the quest for balance between mining and conservation.

A Floresta Nacional de Carajás é uma unidade de conservação federal localizada no sudeste da Amazônia, região Norte do Brasil. Juntamente com outras cinco áreas formam o Mosaico de Carajás com um contínuo de 1.307.000 hectares de área protegida. As principais fitofisionomias presentes no interior da unidade são a Floresta Ombrófila Densa e a Savana Metalófila. A unidade abriga a maior província mineral do mundo. A atividade de mineração promove diferentes impactos sobre a fauna principalmente através da modificação de paisagem originada pela supressão vegetal. O objetivo desse trabalho foi estudar a composição da comunidade de mamíferos de médio e grande porte através do levantamento de informações sobre a riqueza, a abundância e as diferenças entre a composição da mastofauna nas fitofisionomias de Savana Metalófila e Floresta Ombrófila Densa e suas alterações ocasionadas pelo impacto da mineração. Foram realizadas quatro campanhas em 19 trilhas que se distribuíram em áreas de Savana Metalófila e Floresta Ombrófila Densa impactadas e controle. A metodologia utilizada foi de transecção linear e armadilhamento fotográfico com um esforço total empregado de 432 km e 85.920 horas, para cada um dos métodos, respectivamente. A comunidade de mastofauna de médio e grande porte apresentou 43 espécies distribuídas em oito ordens, com um aumento de 41% de novos registros para a região. A composição da comunidade de mastofauna apresentou diferenças quanto a riqueza e a abundância das espécies nas duas fitofisionomias e quanto ao efeito do impacto da mineração. O presente trabalho trouxe avanços em relação à lista de espécies de mamíferos de médio e grande porte e aumentou o conhecimento a respeito da composição desta fauna em ambientes de floresta e de savana na Floresta Nacional de Carajás. Trouxe informações acerca dos impactos sobre a mastofauna e identificou importantes sensibilidades de algumas espécies frente à mineração, contribuindo para a busca do equilíbrio entre a mineração e a conservação. / The National Forest of Carajás is a federal conservation unit located in the southeast of the Amazon, northern Brazil. Together with other five areas make up the mosaic of Carajás with a continuum of 1.307 million hectares of protected area. The main vegetation types present within the unit are the Dense Montane Forest and Savana Metalófila. The unit houses the largest mineral reserves in the world. Mining activity promotes different impacts on fauna mainly by alteration of the landscape caused by vegetation removal and stacking sterile. The aim of this work was to study the composition of the mammal community of medium and large through the collection of information about richness, abundance and differences between vegetation types in the mammalian species composition of Savana Metalófila and Dense Montane Forest and its changes caused by the impact. Were conducted four campaigns and 19 tracks that were distributed in areas of Savana Metalófila and Dense Montane Forest impacted and control. The methodology used was to linetransect and camera trapping employee with a total effort of 432 km and 85.920 hours for each method, respectively. The mammal community of medium and large showed 43 species in eight orders, showing an increase of 41% of new registrations for the region. The community composition of mammal species show differences in richness and abundance of species in two vegetation types and the effect of the impact of mining. This work has brought about improvements to the list of mammalian species of medium and large size and increased knowledge about the composition of this fauna in environments of forest and savanna in the Carajás National Forest. Brought information about the impacts on mammals and identified important sensitivities of some species facing the mining, contributing to the quest for balance between mining and conservation.