Artículos de revistas: "Wetlands South Australia"

1

Halse, SA, MR Williams, RP Jaensch y JAK Lane. "Wetland characteristics and waterbird use of wetlands in south-western Australia". Wildlife Research 20, n.º 1 (1993): 103. http://dx.doi.org/10.1071/wr9930103.

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The presence or absence of 61 waterbird species on 95 wetlands in south-western Australia was related to six wetland characteristics: salinity, emergent vegetation, water depth, pH, phosphorus level and wetland size. More species were associated with salinity and vegetation than with other wetland characteristics. There were more positive associations with brackish than with fresh or saline wetlands and few species occurred in hypersaline wetlands. Trees or shrubs and sedges were the vegetation with which most species were associated; few species were recorded on completely open wetlands or those with only samphire. The 95 wetlands were classified into five groups on the basis of waterbird use. All wetland characteristics differed between groups but larger differences occurred in salinity, vegetation and water depth. The wetland group that supported most species also supported the highest numbers of waterbirds and most breeding species.

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2

Junk, Wolfgang J. "Long-term environmental trends and the future of tropical wetlands". Environmental Conservation 29, n.º 4 (diciembre de 2002): 414–35. http://dx.doi.org/10.1017/s0376892902000310.

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Tropical wetlands assume important functions in the landscape and contribute considerably to the welfare of large parts of the human population, but they are seriously threatened because they are considered free resources of land and water. This review summarizes long-term environmental trends for tropical wetlands and predicts their future to the time horizon 2025. Many tropical countries do not have the economic strength, scientific and technological capacity, and/or administrative infrastructure to adequately react to the challenges of increasing population pressure and globalization of the economy with respect to the sustainable use of the resources. Furthermore, political instability and armed conflicts affect large areas in several tropical countries, hindering wetland research and management. Detailed wetland inventories are missing in most countries, as are plans for a sustainable management of wetlands in the context of a long-term integrated watershed management. Despite large regional variability, a continental ranking shows, in decreasing order of wetland integrity, South America, Africa, Australia and Asia, while efforts to mitigate human impacts on wetlands are largest and most advanced in Australia. Analysis of demographic, political, economic and ecological trends indicates fairly stable conditions for wetlands in tropical Australia, slight deterioration of the large wetland areas in tropical South America excepting the Magdalena and Cauca River flood plains where human population is larger, rapidly increasing pressure and destruction on many African and Central American wetlands and serious threats for the remaining wetlands in tropical Asia, by the year of 2025. Policy deficiencies, deficient planning concepts, limited information and awareness and institutional weakness are the main administrative reasons for wetland degradation and must be overcome to improve wetland management and protection in future. Intensification of international cooperation and assistance is considered of fundamental importance for most tropical countries to solve problems related to wetland research, protection and sustainable management.

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3

Kingsford, R. T., K. Brandis, R. F. Thomas, P. Crighton, E. Knowles y E. Gale. "Classifying landform at broad spatial scales: the distribution and conservation of wetlands in New South Wales, Australia". Marine and Freshwater Research 55, n.º 1 (2004): 17. http://dx.doi.org/10.1071/mf03075.

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Relatively few large-scale inventories of the world's wetlands exist because of the difficulties of spatial scale, associated cost and multiple objectives, often temporally confounded, that drive classification. The extent of wetlands across a large part of Australia (New South Wales, 80.6 million ha) was determined using satellite image analyses. These data allowed analyses of the distribution of wetlands, their conservation status and potential threats at different spatial scales; that is, State, coastal and inland, and catchment. Approximately 5.6% of New South Wales is wetland (4.5 million ha), mostly (96%) in inland river catchments. Broad classification allowed identification of the extent of wetland types: (i) floodplains (89%); (ii) freshwater lakes (6.6%); (iii) saline lakes (< 1%); (iv) estuarine wetlands (2.5%); and (v) coastal lagoons and lakes (1.5%). Conservation reserves protect only 3% of wetland area. The analyses identified the north-west as the key area for wetland conservation as most other catchments have lower wetland extent and more potential threatening processes. The first stage of a large-scale inventory is to determine the extent and location of wetlands, with immediate benefits for strategic conservation and management. Other objectives (e.g. classification, biotic composition, hydrology and threats) seldom have sufficient data available for large-scale inventories but can be completed later with resources.

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4

Wahren, C. H., R. J. Williams y W. A. Papst. "Alpine and Subalpine Wetland Vegetation on the Bogong High Plains, South-eastern Australia". Australian Journal of Botany 47, n.º 2 (1999): 165. http://dx.doi.org/10.1071/bt97106.

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The botanical composition and structure of wetland vegetation from seven sites in the alpine and subalpine tracts of the Bogong High Plains was sampled in 1995 and 1996. Sites were in the vicinity of Mts Nelse, Cope and Fainter. Sampling was based on contiguous 1-m2 quadrats along transects 20−70 m long across each wetland. Samples were ordinated using non-metric multidimensional scaling (NMDS). Floristic variation was assessed both within selected individual wetlands, and between wetlands from different regions. The relationship between the ordinations and environmental variables such as soil surface texture, soil depth and the amount of bare ground was tested by fitting vectors. Three dominant vegetation assemblages were identified. Closed heath, of hygrophyllous, scleromorphic shrubs such as Richea continentis and Baeckea gunniana, the rush Empodisma minus and the moss Sphagnum cristatum occurred on the deeper peats. Low open heath of Epacris glacialis and Danthonia nivicola occurred on shallow peats. Herbfields of Caltha introloba and Oreobolus pumilio occurred on stony pavements in two different physiographic situations&horbar;on relatively steep slopes (10−20°) at the head of wetlands, and on flat ground (slope < 2°), below the head of wetlands. The pavements on the steeper sites appeared to be associated with periglacial features such as solifluction lobes and terraces. Those on the flatter ground appeared to have been derived more recently. Wetlands in the Mt Cope region consisted of closed heath, low open heath and pavement herbfield in various proportions. Wetlands on Mt Fainter, which are subject to heavy trampling by cattle, were in a degraded condition, with a low cover of major hygrophyllous mosses and shrubs, and a high cover of introduced species. Long-ungrazed wetlands in a 50-year exclosure at Rocky Valley had high cover of closed heath, no pavements, numerous ponds and virtually no entrenched drainage channels or exposed peat. The Caltha herbfields are significant features nationally, both floristically and geomorphologically. Alpine and subalpine wetlands have been listed under the Victorian Flora and Fauna Guarantee Act 1988, and continued grazing by cattle is not compatible with the conservation objectives for this alpine vegetation type.

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5

Maher, MT y LW Braithwaite. "Patterns of waterbird use in wetlands of the Paroo, A river system of inland Australia." Rangeland Journal 14, n.º 2 (1992): 128. http://dx.doi.org/10.1071/rj9920128.

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The significance of inland wetlands to Australian waterbirds has been overlooked until recently. One important area identified from regular aerial survey centres on the Paroo River in north-western New South Wales. Between April 1983 and December 1985, a period covering a major flood, waterbird populations were estimated on five wetland systems associated with the Paroo during 14 trips. Fifty- three waterbird species were recorded with the anatids, Anas gibberifrons and Malacorhynchus membranaceus, accounting for 75 per cent of total estimated populations. Most breeding events were observed in those wetlands dominated by Muehlenbeckia florulenta (lignum). Breeding accounted for shifts in waterbird populations between wetland systems. A model of waterbird usage of the five wetland systems in relation to a complete flood event is described. The importance for waterbird conservation of wetlands used for breeding and maintenance of populations between flood events, and threats to the integrity of these wetlands are discussed.

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6

Bino, G., R. T. Kingsford y K. Brandis. "Australia's wetlands – learning from the past to manage for the future". Pacific Conservation Biology 22, n.º 2 (2016): 116. http://dx.doi.org/10.1071/pc15047.

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Australia has diverse wetlands with multiple threats. We reviewed knowledge about the extent of wetlands, representativeness, impacts and threats to integrity and options for effective conservation. Natural Australian wetlands cover an estimated 33 266 245 ha (4.4%), with 55% palustrine (floodplains and swamps), followed by 31% lakes, 10% estuarine systems, and 5% rivers and creeks. The Lake Eyre (1.1%), Murray–Darling (0.73%), Tanami–Timor Sea Coast (0.71%) and the Carpentaria Coast (0.55%) drainage divisions have more wetlands, also reflected in the distributions among states and territories. Ramsar sites and wetlands in protected areas were generally biased towards the southern continent. Overall representation of mapped wetlands was good for lacustrine (40.6%) and estuarine (34.4%), fair for riverine (16.8%), but inadequate for palustrine (10.8%) wetlands. Within drainage divisions, representation varied considerably, with shortfalls from the Aichi target of 17%. Agriculture, urbanisation, pollution and invasive species have degraded or destroyed wetlands, particularly in the developed south-east, south-west and north-east of the continent. Water resource developments, primarily the building of dams, diversion of water and development of floodplains, seriously threaten Australian wetlands, with all threats exacerbated by climate change impacts of rising sea levels and high temperatures. Management and policy for wetlands is dependent on data on distribution, type and extent of wetlands, a key national constraint. Some States are well advanced (e.g. Queensland) and others lack any comprehensive data on the distribution of wetlands. Mitigation of increasing development (e.g. northern Australia) will be critical for conservation, along with increased representativeness in protected areas and restoration, particularly with environmental flows.

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7

Gibson, N., G. J. Keighery, M. N. Lyons y B. J. Keighery. "Threatened plant communities of Western Australia. 2 The seasonal clay-based wetland communities of the South West". Pacific Conservation Biology 11, n.º 4 (2005): 287. http://dx.doi.org/10.1071/pc050287.

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The communities of seasonal clay-based wetlands of south-west Australia are described. They are amongst the most threatened In Western Australia. It is estimated that >90% of the original extent of these communities has been cleared for agriculture, and the remaining areas, despite largely occurring in conservation reserves, are threatened by weed invasion and rising saline groundwater. Thirty-six taxa are identified as claypan specialists occurring in six floristic communities. Composition was strongly correlated with rainfall and edaphic factors. The most consistent attribute shared between the seasonal clay-based wetlands of south-west Australia, and the analogous vernal pools systems of California, Chile, and South Africa was the widespread conversion of these wetlands to agricultural systems. The south-west Australia wetlands had a richer flora, different lifeform composition, higher species richness but fewer claypan specialists than the vernal pools of California. The dissimilarity in the regional floras and vegetation types from which the pool floras were recruited explain these differences.

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8

Mackenzie, Lydia, Henk Heijnis, Patricia Gadd, Patrick Moss y James Shulmeister. "Geochemical investigation of the South Wellesley Island wetlands: Insight into wetland development during the Holocene in tropical northern Australia". Holocene 27, n.º 4 (28 de septiembre de 2016): 566–78. http://dx.doi.org/10.1177/0959683616670219.

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The South Wellesley Islands in the Gulf of Carpentaria, northern Australia, were the recent focus of a palynological investigation which found vegetation change during the Holocene was driven by coastal progradation and regional climate. Here, we present new elemental data from x-ray fluorescence core scanning which provides non-destructive, continuous and high resolution analysis from three wetlands across Bentinck Island, the largest of the South Wellesley Islands. Elemental data and grain size analyses are combined with lead-210 (210Pb) and accelerator mass spectrometry (AMS) carbon-14 (14C) dates. An open coastal environment was present 1250 cal. a BP on the south east coast of Bentinck Island, with sediment supply incorporating fluvial deposition and detrital input of titanium and iron from eroding lateritic bedrock. Prograding shorelines, dune development and river diversion formed a series of swales parallel to the coast by ~800 cal. a BP, forming the Marralda wetlands. Wetlands developed at sites on the north and west coasts ~500 and ~450 cal. a BP, respectively. Geochemical and grain size analyses indicate that wetlands formed as accreting tidal mudflats or within inter-dune swales that intercepted groundwater draining to the coastal margins. The timing of wetland initiation indicates localised late-Holocene sea level regression, stabilisation and coastal plain development in the Gulf of Carpentaria. Elemental data provide new records of wetland development across Bentinck Island, highlighting the value of a multi-proxy approach to understanding environmental change during the Holocene in tropical northern Australia.

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9

Moss, Patrick, John Tibby, Felicity Shapland, Russell Fairfax, Philip Stewart, Cameron Barr, Lynda Petherick, Allen Gontz y Craig Sloss. "Patterned fen formation and development from the Great Sandy Region, south-east Queensland, Australia". Marine and Freshwater Research 67, n.º 6 (2016): 816. http://dx.doi.org/10.1071/mf14359.

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The Great Sandy Region (incorporating Fraser Island and the Cooloola sand-mass), south-east Queensland, contains a significant area of Ramsar-listed coastal wetlands, including the globally important patterned fen complexes. These mires form an elaborate network of pools surrounded by vegetated peat ridges and are the only known subtropical, Southern Hemisphere examples, with wetlands of this type typically located in high northern latitudes. Sedimentological, palynological and charcoal analysis from the Wathumba and Moon Point complexes on Fraser Island indicate two periods of swamp formation (that may contain patterned fens), one commencing at 12 000 years ago (Moon Point) and the other ~4300 years ago (Wathumba). Wetland formation and development is thought to be related to a combination of biological and hydrological processes with the dominant peat-forming rush, Empodisma minus, being an important component of both patterned and non-patterned mires within the region. In contrast to Northern Hemisphere paludifying systems, the patterning appears to initiate at the start of wetland development or as part of an infilling process. The wetlands dominated by E. minus are highly resilient to disturbance, particularly burning and sea level alterations, and appear to form important refuge areas for amphibians, fish and birds (both non-migratory and migratory) over thousands of years.

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10

T. Kingsford, Richard, Rachael F. Thomas y Alison L. Curtin. "Conservation of wetlands in the Paroo and Warrego River catchments in arid Australia". Pacific Conservation Biology 7, n.º 1 (2001): 21. http://dx.doi.org/10.1071/pc010021.

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Irrigation proposals to divert water from the Paroo and Warrego Rivers in arid Australia will affect their aquatic ecosystems. These two are the last of 26 major rivers in the Murray-Darling Basin without large dams and diversions. Knowledge of the extent of their biodiversity value is critical to assessing likely impacts. During the 1990 flood, 1.73 million ha of wetlands, or 12.5% of the land surface of the Paroo and Warrego River catchments, were flooded. Flooded wetland area in the respective catchments was 781 330 ha and 890 534 ha. Most of the wetland area (97%) was floodplain, with 37 freshwater lakes (>50 ha) occupying 2.5% of the wetland area and 177 salt lakes covering 0.8%. A high diversity and abundance of biota depend on these wetlands. Only 7% of the wetland area, all in the Paroo catchment, is in conservation reserves. New South Wales has a high proportion of the wetland area on the Paroo (60%) and a substantial proportion of the wetland area on the Warrego River (23%). Queensland, the upstream state, will influence the ecology of the entire catchment areas of both river systems through its proposed water management plan. Any resulting extraction practices will have detrimental ecological consequences within a decade. Conservation of wetlands is usually site-focused and reflects a paradigm of conservation based on reservation of parcels of land. However, wetlands are dependent on water that is seldom adequately protected. Intergovernment co-operation should protect the entire catchment of the Paroo River from major diversions and stop further development on the Warrego River. This would do more for the conservation of wetlands than the formal reservation of small parts of their catchments.

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11

Venables, Anne y Paul I. Boon. "What environmental, social or economic factors identify high-value wetlands? Data-mining a wetlands database from south-eastern Australia". Pacific Conservation Biology 22, n.º 4 (2016): 312. http://dx.doi.org/10.1071/pc15034.

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Large amounts of potentially useful information are collected by management agencies as they attempt to identify high-value wetlands and rank them for investment, protection or rehabilitation. Resource constraints frequently mean these information-rich databases are not fully interrogated, with the result that much of their expensively obtained information is only partially analysed or, worse, is not analysed at all. The present paper shows the benefit of rigorously interrogating such databases to identify wetlands of high social, economic or environmental value. Three data-mining methods, namely, univariate analysis, multivariate analysis and artificial neural networks (ANNs), were applied to a large (7.6 MB) but hitherto unanalysed database of 163 wetlands in the Gippsland region of south-eastern Australia. Simple statistical techniques, such as univariate analysis and binary logistic regression, identified high-value wetlands with a prediction accuracy of >90%, using only a small set of environmental indicators. Artificial neural network models with nine environmental-value inputs (six direct indicators plus three threat indicators) correctly also identified 90% of high-value wetlands. Outcomes generated by ANNs were in close agreement with those obtained with more traditional univariate and multivariate analyses. There seems little justification for undertaking economic assessments, and for environmental assessments the best indicators consistently included the presence of listed fauna or flora, vegetation intactness and the absence of hydrological modification. The overall approach, although developed from the analysis of a single (but large) wetland database of wetlands in south-eastern Australia, is likely to find conservation applications in many other regions of the Pacific.

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12

Whalley, R. D. B., J. N. Price, M. J. Macdonald y P. J. Berney. "Drivers of change in the Social-Ecological Systems of the Gwydir Wetlands and Macquarie Marshes in northern New South Wales, Australia". Rangeland Journal 33, n.º 2 (2011): 109. http://dx.doi.org/10.1071/rj11002.

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The Murray–Darling Basin is a Social-Ecological System (SES) of major importance to Australia and includes extensive wetland areas in the north-western parts of New South Wales. The Gwydir Wetlands and the Macquarie Marshes are the particular focus of this paper. These two wetland SES have undergone five successive adaptive cycles (phases) since they were first visited by Europeans in the early 19th century and the ecological, economic and social drivers initiating each transformation to a new cycle are described and analysed. The arrival of the European settlers with their domestic livestock rapidly displaced the Indigenous SES and the wetlands were extensively grazed; during wet periods the livestock were moved out of the wetlands and moved back in as the water receded. More recent land-use changes resulted from the building of major dams to enable storage of water for use in irrigated agriculture. A consequence of dam construction and water use has been a reduction in the frequency and extent of flooding, which has allowed many parts of the wetlands to be continually grazed. Furthermore, as machinery capable of cultivating the very heavy textured soils became available, dryland cropping became a major enterprise in areas of the floodplain where the likelihood of flooding was reduced. With the reduction in flooding, these wetland sites have been seriously degraded. The final phase has seen the invasion by an exotic weed, lippia [Phyla canescens (Kunth) Greene], which is a perennial that grows mat-like between other species of plants and spreads to produce a virtually mono-specific stand. The domestic livestock carrying capacity of the land becomes more or less zero and the conservation value of the wetlands is also dramatically decreased. Therefore, we suggest that lippia should be classed as an ecosystem engineer that has caused the latest transformation of these wetland SES and suggest research directions to investigate how they can be managed to revert to a state in which lippia is no longer dominant.

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Navarro, Alejandro, Mary Young, Peter I. Macreadie, Emily Nicholson y Daniel Ierodiaconou. "Mangrove and Saltmarsh Distribution Mapping and Land Cover Change Assessment for South-Eastern Australia from 1991 to 2015". Remote Sensing 13, n.º 8 (8 de abril de 2021): 1450. http://dx.doi.org/10.3390/rs13081450.

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Coastal wetland ecosystems, such as saltmarsh and mangroves, provide a wide range of important ecological and socio-economic services. A good understanding of the spatial and temporal distribution of these ecosystems is critical to maximising the benefits from restoration and conservation projects. We mapped mangrove and saltmarsh ecosystem transitions from 1991 to 2015 in south-eastern Australia, using remotely sensed Landsat data and a Random Forest classification. Our classification results were improved by the addition of two physical variables (Shuttle Radar Topographic Mission (SRTM), and Distance to Water). We also provide evidence that the addition of post-classification, spatial and temporal, filters improve overall accuracy of coastal wetlands detection by up to 16%. Mangrove and saltmarsh maps produced in this study had an overall User Accuracy of 0.82–0.95 and 0.81–0.87 and an overall Producer Accuracy of 0.71–0.88 and 0.24–0.87 for mangrove and saltmarsh, respectively. We found that mangrove ecosystems in south-eastern Australia have lost an area of 1148 ha (7.6%), whilst saltmarsh experienced an overall increase in coverage of 4157 ha (20.3%) over this 24-year period. The maps developed in this study allow local managers to quantify persistence, gains, and losses of coastal wetlands in south-eastern Australia.

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14

Halse, S. A., J. K. Ruprecht y A. M. Pinder. "Salinisation and prospects for biodiversity in rivers and wetlands of south-west Western Australia". Australian Journal of Botany 51, n.º 6 (2003): 673. http://dx.doi.org/10.1071/bt02113.

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Saline water was common in south-west Western Australian aquatic systems prior to land-clearing because most streams and wetlands were ephemeral and evapo-concentrated as they dried, and there were high concentrations of stored salt in groundwater and soil profiles. Nevertheless, a 1998 review of salinity trends in rivers of south-west Western Australia showed that 20-fold increases in salinity concentrations had occurred since clearing in the medium-rainfall zone (300–700 mm). More recent data confirm these trends and show that elevated salinities have already caused substantial changes to the biological communities of aquatic ecosystems. Further substantial changes will occur, despite the flora and fauna of the south-west being comparatively well adapted to the presence of salinity in the landscape. Up to one-third of wetland and river invertebrate species, large numbers of plants and a substantial proportion of the waterbird fauna will disappear from the wheatbelt, a region that has high biodiversity value and endemism. Increased salinities are not the only threat associated with salinisation: increased water volumes, longer periods of inundation and more widespread acidity are also likely to be detrimental to the biota.

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15

Higgisson, William, Adrian Cobb, Alica Tschierschke y Fiona Dyer. "The Role of Environmental Water and Reedbed Condition on the Response of Phragmites australis Reedbeds to Flooding". Remote Sensing 14, n.º 8 (13 de abril de 2022): 1868. http://dx.doi.org/10.3390/rs14081868.

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Globally, wetlands have experienced significant declines in area and condition. Reedbeds are a key attribute of many wetlands and are typically composed of Phragmites australis (common reed), a globally distributed emergent aquatic perennial grass. Environmental water is increasingly used to support functioning river and floodplain ecosystems, including reedbeds, where maintaining wetland vegetation condition is a common objective. Drone-based remote sensing allows for the consistent collection of high-quality data in locations such as wetlands where access is limited. We used unoccupied aerial vehicles (UAVs) and convolutional neural networks (CNNs) to estimate the cover of Phragmites australis and examine the role of reedbed condition and prior environmental watering in the response of reedbeds to flooding. Data were collected from a large inland reedbed in semi-arid western New South Wales, Australia between October 2019 and March 2021 using UAVs and processed using CNNs. Prior to the flood event, sites that had received environmental water had a significantly greater cover of Phragmites australis. The sites that were not managed with environmental water had very low cover (<1%) of reeds prior to the flood event and transitioned from a Critical condition to a Poor or Medium condition following flooding. Using UAVs and CNNs we demonstrated the role environmental water plays in filling the gaps between large flood events and maintaining the condition and resilience of reedbeds.

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Boon, Paul I., Kerri L. Muller y George G. Ganf. "Methane emissions from diverse wetlands in south-eastern Australia". SIL Proceedings, 1922-2010 27, n.º 3 (noviembre de 2000): 1382–86. http://dx.doi.org/10.1080/03680770.1998.11901462.

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Ling, J. E., M. T. Casanova, I. Shannon y M. Powell. "Development of a wetland plant indicator list to inform the delineation of wetlands in New South Wales". Marine and Freshwater Research 70, n.º 3 (2019): 322. http://dx.doi.org/10.1071/mf18114.

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Wetlands experience fluctuating water levels, so their extent varies spatially and temporally. This characteristic is widespread and likely to increase as global temperatures and evaporation rates increase. The temporary nature of wetlands can confound where a wetland begins and ends, resulting in unreliable mapping and determination of wetland areas for inventory, planning or monitoring purposes. The occurrence of plants that rely on the presence of water for part or all of their life history can be a reliable way to determine the extent of water-affected ecosystems. A wetland plant indicator list (WPIL) could enable more accurate mapping and provide a tool for on-ground validation of wetland boundaries. However, this introduces the problem of the definition of ‘wetland plant’, especially with species that can tolerate, or require, water level fluctuation, and that respond to flooding or drought by adjusting their morphology or phenology (i.e. ‘amphibious’ plants and those that grow only during drawdown). In this study we developed a WPIL through a process of expert elicitation. The expert decisions were compared and standardised for each species. It is envisaged that this work will lead to a comprehensive listing of wetland plants for Australia for the purposes of planning, mapping and management.

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18

Wen, Li y Michael G. Hughes. "Coastal Wetland Responses to Sea Level Rise: The Losers and Winners Based on Hydro-Geomorphological Settings". Remote Sensing 14, n.º 8 (14 de abril de 2022): 1888. http://dx.doi.org/10.3390/rs14081888.

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Many coastal wetlands are under pressure due to climate change and the associated sea level rise (SLR). Many previous studies suggest that upslope lateral migration is the key adaptive mechanism for saline wetlands, such as mangroves and saltmarshes. However, few studies have explored the long-term fate of other wetland types, such as brackish swamps and freshwater forests. Using the current wetland map of a micro-tidal estuary, the Manning River in New South Wales, Australia, this study built a machine learning model based on the hydro-geomorphological settings of four broad wetland types. The model was then used to predict the future wetland distribution under three sea level rise scenarios. The predictions were compared to compute the persistence, net, swap, and total changes in the wetlands to investigate the loss and gain potential of different wetland classes. Our results for the study area show extensive gains by mangroves under low (0.5 m), moderate (1.0 m), and high (1.5 m) sea level rise scenarios, whereas the other wetland classes could suffer substantial losses. Our findings suggest that the accommodation spaces might only be beneficial to mangroves, and their availability to saltmarshes might be limited by coastal squeeze at saline–freshwater ecotones. Furthermore, the accommodation spaces for freshwater wetlands were also restrained by coastal squeeze at the wetland-upland ecotones. As sea level rises, coastal wetlands other than mangroves could be lost due to barriers at the transitional ecotones. In our study, these are largely manifested by slope impacts on hydrology at a higher sea level. Our approach provides a framework to systematically assess the vulnerability of all coastal wetland types.

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Robinson, Randall W., Paul I. Boon, Nina Sawtell, Elizabeth A. James y Robert Cross. "Effects of environmental conditions on the production of hypocotyl hairs in seedlings of Melaleuca ericifolia (swamp paperbark)". Australian Journal of Botany 56, n.º 7 (2008): 564. http://dx.doi.org/10.1071/bt06186.

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The production of hypocotyl hairs in the early stages of seedling development can strongly influence the success with which plants recruit sexually in harsh environments. Although wetlands are one type of environment in which seedlings might be expected to develop hypocotyl hairs, there have been few studies of these structures in the woody aquatic plants. We investigated the production of hypocotyl hairs in Melaleuca ericifolia Sm., a small wetland tree widely distributed across swampy coastal areas of south-eastern Australia, in relation to water availability, salinity, temperature and light regime. Hypocotyl hairs were ~20 mm long × 30 μm wide; in contrast, root hairs were generally less than 5 mm long and 15 μm wide. Hypocotyl hairs were produced only under a narrow range of environmental conditions—low salinity, low water availability, moderate temperature, and darkness—and seedlings that failed to produce hypocotyl hairs did not survive. Since the conditions under which hypocotyl hairs were produced were at least as, and possibly even more, restricted than those required for successful germination of seeds, it is likely that the successful sexual recruitment of M. ericifolia would be rare and episodic under conditions existing in most coastal wetlands in south-eastern Australia.

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20

Raisin, G. W. y D. S. Mitchell. "The use of wetlands for the control of non-point source pollution". Water Science and Technology 32, n.º 3 (1 de agosto de 1995): 177–86. http://dx.doi.org/10.2166/wst.1995.0139.

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There is increasing interest in the use of wetlands to intercept nutrients in diffuse run-off from rural catchments. However, the scientific basis for this strategy is far from secure. While research in several countries provides support for this approach, there is a general lack of rigorous data sets of nutrient balances showing the real effect of such wetlands on the quality of run-off emanating from rural catchments. Research being conducted on two natural and one constructed wetlands in south-eastern Australia will contribute to filling this gap. In each of these three wetlands, volume of inflow and outflow is being measured at 15 minute intervals. Automatic water samplers connected to the flow measurement device are measured and are triggered to take samples at appropriate intervals during run-off events. All these water samples are analysed chemically and the total loads of selected chemicals entering and leaving a wetland are calculated for several storm events over the winter and spring period during 1993. Results for Total Nitrogen and Total Phosphorus show that during winter there is a net release of these nutrients from the linear wetlands with greater flows resulting in greater flushing. However, in spring and early summer there was a net retention of nutrients in the wetlands despite similar hydrological loadings. These results were affected by the size of the wetland relative to the catchment (and therefore retention time), land use of the catchment, any intrusion of ground water and the nature of the wetland in terms of its shape and vegetation.

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21

Mackenzie, Lydia, Patrick Moss y Sean Ulm. "A late-Holocene record of coastal wetland development and fire regimes in tropical northern Australia". Holocene 30, n.º 10 (16 de junio de 2020): 1379–90. http://dx.doi.org/10.1177/0959683620932970.

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This study presents three records of environmental change during the late-Holocene from wetlands across Bentinck Island in the South Wellesley Islands, northern Australia. Radiometric dating provided ages for sediment cores with the longest chronology spanning the last 1250 cal. yr BP. Palynological results show the diverse mangrove community transitioned to woodland- and wetland-dominated vegetation over the last 850 years on the southeast coast. The key driver of this landscape change was likely late-Holocene sea level regression and coastal progradation in the Gulf of Carpentaria. This study found freshwater wetlands expanded across Bentick Island over the last 500 years, with sedges and rushes peaking in the last 350 years. Macroscopic and microscopic charcoal records, coupled with archaeological evidence, highlights the spatial and temporal variation in fire regimes across the island, reflecting the traditional fire management practices of the Kaiadilt people during the late-Holocene. This study finds a significant increase in charcoal accumulation in the 1900s when Kaiadilt fire practices were disrupted and the South Wellesley Islands were abandoned. The pollen record reflects little change in the vegetation despite the shifting fire regime, highlighting the importance of multi-proxy approaches to reconstructing past environments in tropical northern Australia where vegetation is adapted to fire.

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22

Hurst, Thomas y Paul I. Boon. "Agricultural weeds and coastal saltmarsh in south-eastern Australia: an insurmountable problem?" Australian Journal of Botany 64, n.º 4 (2016): 308. http://dx.doi.org/10.1071/bt16027.

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It is often assumed that saline coastal wetlands experience environmental conditions so severe that they are largely immune to invasion by exotic plant species. The belief is implicit in many older reviews of threats to mangroves and coastal saltmarshes, where a limited range of vascular plant taxa, often focussing on *Spartina, (throughout the paper an asterisk denotes an introduced (exotic) species as per Carr 2012) have been invoked as the major species of concern. Even though the weed flora of southern Australia is derived largely from agriculture and horticulture, neither of which includes many species tolerant of waterlogged, variably saline environments, a recent assessment of Victorian saline coastal wetlands indicated that exotic plants were the third-most pervasive threat, after land ‘reclamation’ and grazing. Tall wheat grass, *Lophopyrum ponticum (Podp.) A.Love., is one of the most severe and widely distributed weeds of saline coastal wetlands in south-eastern Australia. It is promoted by the agricultural extension arm of the Victorian government as a salt-tolerant pasture grass; however, its broad ecological amplitude and robust life form make it a most serious invader of upper saltmarsh in Victoria. We assessed the effectiveness of different control measures, including slashing and herbicides, for the management of *L. ponticum infestations (and their side effects on saltmarsh communities) in the Western Port region of Victoria. A nominally monocot-specific herbicide widely used to control *Spartina, Fluazifop-P, was ineffective in controlling *L. ponticum. The broad-spectrum systemic herbicide glyphosate was more effective in controlling *L. ponticum, but had undesirable impacts on native plant species. Controlling weeds in coastal wetlands using available herbicides for use near coastal waterways would seem to remain problematic.

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23

Bachmann, Mark R. "Restoration journey of the Piccaninnie Ponds Karst Wetlands, South Australia". Ecological Management & Restoration 17, n.º 2 (mayo de 2016): 102–11. http://dx.doi.org/10.1111/emr.12207.

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24

Gibson, Robert, Barry J. Conn y Jeremy J. Bruhl. "Morphological evaluation of the Drosera peltata complex (Droseraceae)". Australian Systematic Botany 25, n.º 1 (2012): 49. http://dx.doi.org/10.1071/sb11030.

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A phenetic study of morphological characters of the Drosera peltata complex (Droseraceae) supports the recognition of the following taxa: D. peltata from wetlands of south-eastern Australia; D. auriculata from south-eastern Australia and New Zealand; the morphologically variable D. hookeri from south-eastern Australia and northern New Zealand; the widespread D. lunata from southern and South-East Asia, as well as northern and north-eastern Australia; and the new species D. yilgarnensis R.P.Gibson & B.J.Conn is here described, from around granite outcrops of south-western Australia. D. bicolor from south-western Australia is recognised as a distinct species outside of the D. peltata complex. D. insolita, considered until recently as a distinct species, is reduced to synonymy of D. lunata. Phenotypic plasticity, vegetative similarity and fleetingly produced diagnostic floral and seed characters within the complex pose significant challenges in understanding the taxonomy of these taxa.

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25

Webb, Cameron Ewart, Raffaele Catanzariti y Steven Hodosi. "Response of Mosquitoes Associated with Estuarine Wetlands to Bushfire in Australia". Journal of the American Mosquito Control Association 37, n.º 2 (1 de junio de 2021): 101–5. http://dx.doi.org/10.2987/20-6972.1.

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ABSTRACT The response of mosquitoes to bushfire is poorly understood. During the 2019–20 summer, many regions of Australia were impacted by devastating bushfires. An area of estuarine and brackish-water wetlands alongside the Georges River, Sydney, New South Wales, was burned in January 2020. Mosquito populations within the area were monitored as part of the local authority's mosquito management program, providing a unique opportunity to record the response of key mosquitoes of pest and public health concern to bushfire. Ground pools within a tidally influenced swamp oak forest dominated by Casuarina glauca and associated wetlands dominated by Phragmites australis and Bolboschoenus spp. had been identified as suitable habitat for a range of mosquitoes, including Aedes alternans, Ae. vigilax, and Verrallina funerea. Surveys of immature stages of mosquitoes within recently burned habitats inundated by tides demonstrated that mosquito eggs survived the direct and indirect impacts of fire and immature stages successfully completed development as reflected in concomitant changes in adult mosquito populations following the bushfire. This unique observation has implications for mosquito management following bushfire in Australia and internationally.

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26

Ocock, J. F., K. J. Brandis, B. J. Wolfenden, K. M. Jenkins y S. Wassens. "Gut content and stable isotope analysis of tadpoles in floodplain wetlands". Australian Journal of Zoology 66, n.º 4 (2018): 261. http://dx.doi.org/10.1071/zo18043.

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Larval amphibians (tadpoles) are an important link in aquatic food webs, as they can be highly abundant consumers and prey for a wide variety of predators. Most tadpoles are considered omnivores, predominately grazing on algae, detritus and macrophytes, though recent work has identified greater plasticity and breadth in diet than previously considered. We used gut content and stable isotope analysis (SIA) in a baseline study to determine the important dietary items (ingested material) and food sources (assimilated material) for tadpoles of two abundant generalist frog species in regulated floodplain wetlands of the Murrumbidgee River, south-east Australia. We identified a wide variety of dietary items in the gut contents, including whole microcrustaceans, filamentous algae and macrophytes. The composition of several ingested food items was correlated with their availability in each wetland. However, SIA identified biofilm as the food source most consistently assimilated across several wetlands, though microcrustaceans and algae contributed when abundant. Biofilm is likely the most important basal food item for tadpoles in floodplain wetlands because it is ubiquitous and has a high nutritional quality. Identifying important food sources is a crucial step towards developing management strategies for promoting tadpole recruitment in regulated wetlands.

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27

Macdonald, Jed I., Zeb D. Tonkin, David S. L. Ramsey, Andrew K. Kaus, Alison K. King y David A. Crook. "Do invasive eastern gambusia (Gambusia holbrooki) shape wetland fish assemblage structure in south-eastern Australia?" Marine and Freshwater Research 63, n.º 8 (2012): 659. http://dx.doi.org/10.1071/mf12019.

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Defining the ecological impacts conferred by invasive fishes provides a framework for evaluating the feasibility of control efforts in invaded waterways, and for predicting the consequences of future incursions. Eastern gambusia (Gambusia holbrooki) is a remarkably successful invader of freshwater systems worldwide, with the capacity to detrimentally impact native fishes both directly (e.g. competition, predation, agonistic interactions) and indirectly (e.g. triggering trophic cascades). Here, we modelled the influence of eastern gambusia and several environmental covariates on fish species diversity, abundance and condition based on quantitative survey data collected from 93 wetlands in south-eastern Australia. We predicted that small-bodied, wetland specialist species sharing dietary- and habitat-niches with eastern gambusia would be most severely impacted, and that environmental stressors associated with wetland drying during late summer would magnify these impacts. Eastern gambusia influenced the occurrence, abundance and/or body condition of most common wetland species; however, the direction and level of impact appeared dependent on both biotic and environmental forces. From these results, we postulate that generalist life-history strategies that permit niche-segregation may release some native species from competitive/predatory pressures, allowing coexistence with eastern gambusia in resource-limited, environmentally harsh habitats, whilst specialist species that occupy narrower ecological niches may be less resistant.

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28

Peacock, David, Gresley A. Wakelin-King y Ben Shepherd. "Cane toads (Rhinella marina) in south-western Queensland: invasion front, spread and how Cooper Creek geomorphology could enable invasion into north-eastern South Australia". Australian Journal of Zoology 62, n.º 5 (2014): 366. http://dx.doi.org/10.1071/zo14025.

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The invasion of northern Australia by the poisonous cane toad is well recognised, as is its devastating impacts on numerous local native species. However, there is little recognition that the toads are spreading into south-western Queensland. Utilising local knowledge, a limited survey was undertaken within the Cooper Creek catchment to locate the invasion front. Dispersal during 2010–11 floods has established cane toads as far south as Jundah. Integrating this information with landform mapping indicates that cane toad invasion can continue south-west down the Cooper Creek. Though arid, Cooper Creek’s geomorphology renders it partially independent of local climate, and permanent and semipermanent waterholes (including RAMSAR-listed wetlands) are found downstream from Windorah and into the Strzelecki Desert. Natural landforms provide potential daytime shelter and breeding sites, and additional suitable habitat created by human activity is also widespread. Even unsuccessful attempts at breeding may be detrimental to regional ecology, especially fish populations, at critical stages of their boom/bust cycle. We conclude that there is no reason why cane toads cannot penetrate further down the Cooper Creek, threatening wetlands in north-eastern South Australia. Published models of cane toad expansion, which conclude that north-eastern South Australia is too dry for cane toad populations to establish, are based on climatic parameters that significantly under-represent true habitat availability.

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29

Gibson, N., K. Brown y G. Paczkowska. "Temporal changes in threatened ephemeral claypans over annual and decadal timescales in south-west Australia". Australian Journal of Botany 66, n.º 8 (2018): 609. http://dx.doi.org/10.1071/bt18067.

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The vegetation of the ephemeral claypans of south-west Australia were first described over 100 years ago. Since then they have been almost totally cleared for agriculture and urban development and are currently listed as critically endangered. These claypans have many similarities with ephemeral wetlands found in other Mediterranean climate regions with significant species turnover both within and between claypans and fine scale patterning highly correlated with micro-topography. Although annual variation in species composition was apparent there was also a consistent trend of increasing exotic taxa richness due to higher recruitment rates. This increasing exotic richness is of note, as the major threat to these communities is the invasion by a small number South African taxa, which can establish dense monocultures across these wetlands. Over the last two decades these invasive taxa have spread into 37% of the previously non-invaded quadrats. As remnant size was not a good predictor of their occurrence all remnants should be considered vulnerable. Management of these invasive taxa will be the major conservation issue in these threatened wetlands into the future.

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30

Carnell, Paul E., Saras M. Windecker, Madeline Brenker, Jeff Baldock, Pere Masque, Kate Brunt y Peter I. Macreadie. "Carbon stocks, sequestration, and emissions of wetlands in south eastern Australia". Global Change Biology 24, n.º 9 (24 de junio de 2018): 4173–84. http://dx.doi.org/10.1111/gcb.14319.

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31

Zhang, Yang y Samsung Lim. "Drivers of Wildfire Occurrence Patterns in the Inland Riverine Environment of New South Wales, Australia". Forests 10, n.º 6 (24 de junio de 2019): 524. http://dx.doi.org/10.3390/f10060524.

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In the inland riverine environment of Australia, wildfires not only threaten human life and cause economic loss but also make distinctive impacts on the ecosystem (e.g., injuring or killing fire-sensitive wetland species such as the river red gum). Understanding the drivers of wildfire occurrence patterns in this particular environment is vital for fire-risk reduction and ecologically sustainable management. This study investigated patterns and driving factors of wildfire occurrence over the years from 2001 to 2016 and across the New South Wales side of the Riverina bioregion. Descriptive analyses were conducted for fires of different causes and that burned different vegetation types. Logistic regression models were developed by incorporating factors that provide information on weather, climate, fuel, topography and ignition sources. Analyses revealed that most fires occurred in summer, with human-caused fires primarily in spring and summer, and natural fires in summer. Summer was the most fire-prone season in forested wetlands, whereas fires in drylands mostly occurred during spring and summer. Fire probabilities were higher under severe weather conditions, in areas with higher annual rainfall, in forested wetlands and in areas with intermediate inundation frequencies. Special attention needs to be paid to the effects of vegetation type and inundation frequency on fire occurrence. Weather, climate&fuel and ignition sources were comparably important in explaining human-caused fire occurrence, whereas weather was more important than climate&fuel in explaining natural fire occurrence. Understandings obtained from this study can potentially support the planning of fire and forest management, as well as to supplement the relatively scarce knowledge on riverine wildfire occurrence.

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32

Casanova, Michelle T. y I. Joan Powling. "What makes a swamp swampy? Water regime and the botany of endangered wetlands in western Victoria". Australian Journal of Botany 62, n.º 6 (2014): 469. http://dx.doi.org/10.1071/bt14119.

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Freshwater temporary wetlands are a little-studied ecosystem worldwide. They have been recognised as critically endangered in south-eastern Australia under Australian biodiversity conservation legislation. However, little has been recorded about their hydrology, functioning or biodiversity values; i.e. the factors that make them intrinsically ‘swampy’. In this paper, we developed a simple threshold model of wetland hydrology based on historical rainfall records and calculated evaporation records matched to records and recollections of the owners of swamps, and documented water-plant and microalgal species richness. The model indicated that swamps were inundated to at least 10-cm depth in an average of 6.3 years per decade for most of the 20th century. The average dry time between inundations was 1.27 years (maximum of 4.5 years). Since 1998, the frequency of inundation appears to have decreased, and the average dry times have increased. Despite, or because of, their temporary nature, these swamps have high biodiversity values among the vegetation and the microalgae, more than has been recorded for near-by permanent wetlands. There is no evidence that a drier and warmer climate will have a negative impact on biodiversity values; however, land management is likely to be important for maintaining these systems as the climate changes.

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33

Mo, Matthew. "Red-eared Sliders Trachemys scripta elegans in southern Sydney, including new incursions". Australian Zoologist 40, n.º 2 (diciembre de 2019): 314–25. http://dx.doi.org/10.7882/az.2018.022.

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The invasive Red-eared Slider Trachemys scripta elegans has spread extensively, forming naturalised populations on all continents except Antarctica. Ranked among the 100 worst invasive species, there are biosecurity concerns that native turtles become outcompeted and displaced, as well as other speculative impacts. The actual ecological impacts in Australia have not been properly studied, however impacts shown in other countries are concerning. Incursions have presented in New South Wales, Queensland, Victoria, Western Australia and the Australian Capital Territory. A number of sightings have been reported from southern Sydney, including six sites where more than one slider has persisted. The incursions at Yeramba Lagoon in the Georges River National Park and the Centennial Parklands have been the most documented, whereas incursions in the Lime Kiln Bay Wetland, Rockdale Wetlands Corridor and Audley in the Royal National Park appear to have occurred recently. To date, breeding in southern Sydney has only been confirmed at Yeramba Lagoon. A range of removal techniques have been successfully applied to eradicate isolated incursions in Brisbane and Melbourne. However, these options are difficult to implement in southern Sydney sites where incursions occur in high visitation public lands.

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34

Breda, Angelo, Patricia M. Saco, Steven G. Sandi, Neil Saintilan, Gerardo Riccardi y José F. Rodríguez. "Accretion, retreat and transgression of coastal wetlands experiencing sea-level rise". Hydrology and Earth System Sciences 25, n.º 2 (18 de febrero de 2021): 769–86. http://dx.doi.org/10.5194/hess-25-769-2021.

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Abstract. The vulnerability of coastal wetlands to future sea-level rise (SLR) has been extensively studied in recent years, and models of coastal wetland evolution have been developed to assess and quantify the expected impacts. Coastal wetlands respond to SLR by vertical accretion and landward migration. Wetlands accrete due to their capacity to trap sediments and to incorporate dead leaves, branches, stems and roots into the soil, and they migrate driven by the preferred inundation conditions in terms of salinity and oxygen availability. Accretion and migration strongly interact, and they both depend on water flow and sediment distribution within the wetland, so wetlands under the same external flow and sediment forcing but with different configurations will respond differently to SLR. Analyses of wetland response to SLR that do not incorporate realistic consideration of flow and sediment distribution, like the bathtub approach, are likely to result in poor estimates of wetland resilience. Here, we investigate how accretion and migration processes affect wetland response to SLR using a computational framework that includes all relevant hydrodynamic and sediment transport mechanisms that affect vegetation and landscape dynamics, and it is efficient enough computationally to allow the simulation of long time periods. Our framework incorporates two vegetation species, mangrove and saltmarsh, and accounts for the effects of natural and manmade features like inner channels, embankments and flow constrictions due to culverts. We apply our model to simplified domains that represent four different settings found in coastal wetlands, including a case of a tidal flat free from obstructions or drainage features and three other cases incorporating an inner channel, an embankment with a culvert, and a combination of inner channel, embankment and culvert. We use conditions typical of south-eastern Australia in terms of vegetation, tidal range and sediment load, but we also analyse situations with 3 times the sediment load to assess the potential of biophysical feedbacks to produce increased accretion rates. We find that all wetland settings are unable to cope with SLR and disappear by the end of the century, even for the case of increased sediment load. Wetlands with good drainage that improves tidal flushing are more resilient than wetlands with obstacles that result in tidal attenuation and can delay wetland submergence by 20 years. Results from a bathtub model reveal systematic overprediction of wetland resilience to SLR: by the end of the century, half of the wetland survives with a typical sediment load, while the entire wetland survives with increased sediment load.

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35

Shamsi, S., A. Turner y S. Wassens. "Description and genetic characterization of a newContracaecumlarval type (Nematoda: Anisakidae) from Australia". Journal of Helminthology 92, n.º 2 (5 de mayo de 2017): 216–22. http://dx.doi.org/10.1017/s0022149x17000360.

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AbstractNematode parasites belonging to the genusContracaecumare economically important parasites with zoonotic significance. AdultContracaecumspp. are found in the stomach of marine mammals or piscivorous birds, and larval stages infect a wide range of invertebrates and fish species. Human infection withContracaecumlarvae has been reported in Australia and other countries after the consumption of infected fish. Although the genusContracaecumcomprises numerous species, thus far only fourContracaecumlarval types have been specifically identified, therefore their life cycle and biology are not yet fully understood. In this study, a newContracaecumlarva (type IV), found in the intestinal tissue of carp caught from Coonancoocabil Lagoon, New South Wales, Australia, is described and characterized genetically. It was identified asContracaecum bancrofti,a unique Australian species reported previously from the Australian pelican in Northern Territory, New South Wales, Victoria and South Australia. This study highlights the role of migratory birds and introduced fish species, such as carp, in distributing zoonotic pathogens not only across the continent but also from marine to freshwater systems. Coonancoocabil Lagoon is located in the Murrumbidgee Valley National Park, a highly managed conservation area with native fish in wetlands located in close proximity to several fish farms and hatcheries. Infection of a highly resilient invasive fish species, such as carp, with a zoonotic parasite of low host specificity, such asContracaecumlarvae, should be alarming for aquaculture and environmental authorities.

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36

Lyon, Jarod, Ivor Stuart, David Ramsey y Justin O'Mahony. "The effect of water level on lateral movements of fish between river and off-channel habitats and implications for management". Marine and Freshwater Research 61, n.º 3 (2010): 271. http://dx.doi.org/10.1071/mf08246.

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Off-channel habitats, such as wetlands and backwaters, are important for the productivity of river systems and for many species of native fish. This study aimed to investigate the fish community, timing and cues that stimulated movement to and from off-channel habitats in the highly regulated Lake Hume to Lake Mulwala reach of the Murray River, south-eastern Australia. In 2004–05, 193 712 fish were collected moving bi-directionally between a 50-km section of the Murray River and several off-channel habitats. Lateral fish movements approximated water level fluctuations. Generally as water levels rose, fish left the main river channel and moved into newly flooded off-channel habitats; there was bi-directional movement as water levels peaked; on falling levels fish moved back to the permanent riverine habitats. Fish previously classified as ‘wetland specialists’, such as carp gudgeons (Hypseleotris spp.), have a more flexible movement and life-history strategy including riverine habitation. The high degree of lateral movement indicates the importance of habitat connectivity for the small-bodied fish community. Wetlands adjacent to the Murray River are becoming increasingly regulated by small weirs and ensuring lateral fish movement will be important in maintaining riverine-wetland biodiversity.

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37

Lamontagne, S., W. S. Hicks, R. W. Fitzpatrick y S. Rogers. "Sulfidic materials in dryland river wetlands". Marine and Freshwater Research 57, n.º 8 (2006): 775. http://dx.doi.org/10.1071/mf06057.

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Due to a combination of river regulation, dryland salinity and irrigation return, lower River Murray floodplains (Australia) and associated wetlands are undergoing salinisation. It was hypothesised that salinisation would provide suitable conditions for the accumulation of sulfidic materials (soils and sediments enriched in sulfides, such as pyrite) in these wetlands. A survey of nine floodplain wetlands representing a salinity gradient from fresh to hypersaline determined that surface sediment sulfide concentrations varied from <0.05% to ~1%. Saline and permanently flooded wetlands tended to have greater sulfide concentrations than freshwater ones or those with more regular wetting–drying regimes. The acidification risk associated with the sulfidic materials was evaluated using field peroxide oxidations tests and laboratory measurements of net acid generation potential. Although sulfide concentration was elevated in many wetlands, the acidification risk was low because of elevated carbonate concentration (up to 30% as CaCO3) in the sediments. One exception was Bottle Bend Lagoon (New South Wales), which had acidified during a draw-down event in 2002 and was found to have both actual and potential acid sulfate soils at the time of the survey (2003). Potential acid sulfate soils also occurred locally in the hypersaline Loveday Disposal Basin. The other environmental risks associated with sulfidic materials could not be reliably evaluated because no guideline exists to assess them. These include the deoxygenation risk following sediment resuspension and the generation of foul odours during drying events. The remediation of wetland salinity in the Murray–Darling Basin will require that the risks associated with disturbing sulfidic materials during management actions be evaluated.

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Brinson, Mark M. y Ana Inés Malvárez. "Temperate freshwater wetlands: types, status, and threats". Environmental Conservation 29, n.º 2 (junio de 2002): 115–33. http://dx.doi.org/10.1017/s0376892902000085.

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This review examines the status of temperate-zone freshwater wetlands and makes projections of how changes over the 2025 time horizon might affect their biodiversity. The six geographic regions addressed are temperate areas of North America, South America, northern Europe, northern Mediterranean, temperate Russia, Mongolia, north-east China, Korea and Japan, and southern Australia and New Zealand. Information from the recent technical literature, general accounts in books, and some first-hand experience provided the basis for describing major wetland types, their status and major threats. Loss of biodiversity is a consequence both of a reduction in area and deterioration in condition. The information base for either change is highly variable geographically. Many countries lack accurate inventories, and for those with inventories, classifications differ, thus making comparisons difficult. Factors responsible for losses and degradation include diversions and damming of river flows, disconnecting floodplain wetlands from flood flows, eutrophication, contamination, grazing, harvests of plants and animals, global warming, invasions of exotics, and the practices of filling, dyking and draining. In humid regions, drainage of depressions and flats has eliminated large areas of wetlands. In arid regions, irrigated agriculture directly competes with wetlands for water. Eutrophication is widespread, which, together with effects of invasive species, reduces biotic complexity. In northern Europe and the northern Mediterranean, losses have been ongoing for hundreds of years, while losses in North America accelerated during the 1950s through to the 1970s. In contrast, areas such as China appear to be on the cusp of expanding drainage projects and building impoundments that will eliminate and degrade freshwater wetlands. Generalizations and trends gleaned from this paper should be considered only as a starting point for developing world-scale data sets. One trend is that the more industrialized countries are likely to conserve their already impacted, remaining wetlands, while nations with less industrialization are now experiencing accelerated losses, and may continue to do so for the next several decades. Another observation is that countries with both protection and restoration programmes do not necessarily enjoy a net increase in area and improvement in condition. Consequently, both reductions in the rates of wetland loss and increases in the rates of restoration are needed in tandem to achieve overall improvements in wetland area and condition.

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39

Kobayashi, Tsuyoshi, Timothy J. Ralph, Pranay Sharma y Simon M. Mitrovic. "Influence of historical inundation frequency on soil microbes (Cyanobacteria, Proteobacteria, Actinobacteria) in semi-arid floodplain wetlands". Marine and Freshwater Research 71, n.º 5 (2020): 617. http://dx.doi.org/10.1071/mf18468.

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Cyanobacteria and other microbes are important moderators of biogeochemical processes in semi-arid floodplain wetlands with varying inundation regimes. Inundation is a key environmental driver for floodplain biological communities. Little is known about the effect of historical inundation frequency on the spatial abundance of floodplain–wetland Cyanobacteria and other microbes. In this study, soil samples were collected at two locations with a gradient of low-to-high inundation frequency in the Macquarie Marshes, south-east Australia. We used high-throughput sequencing to estimate the proportional abundance of the soil Cyanobacteria and other dominant microbes, targeting the bacterial 16S rRNA gene. Of the microbes recovered, Cyanobacteria constituted proportionally a minor component, relative to other dominant phyla like Proteobacteria and Actinobacteria. Linear regression (generalised least-squares) models accounting for spatial autocorrelation showed that historical inundation frequency had no significant effect on the proportional abundance of Cyanobacteria at both wetlands studied. However, inundation frequency had a significant positive effect on the proportional abundance of Proteobacteria and a significant negative effect on the proportional abundance of Actinobacteria. Cyanobacteria seem to occupy a different hydrological niche from Proteobacteria and Actinobacteria in semi-arid floodplain wetlands, suggesting taxon-dependent response of floodplain microbial communities to varying inundation regimes and associated soil conditions in those environments.

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40

Higgisson, William, Linda Broadhurst, Foyez Shams, Bernd Gruber y Fiona Dyer. "Reproductive Strategies and Population Genetic Structure in Two Dryland River Floodplain Plants, Marsilea drummondii and Eleocharis acuta". Genes 13, n.º 9 (23 de agosto de 2022): 1506. http://dx.doi.org/10.3390/genes13091506.

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Aquatic plants share a range of convergent reproductive strategies, such as the ability to reproduce both sexually and asexually through vegetative growth. In dryland river systems, floodplain inundation is infrequent and irregular, and wetlands consist of discrete and unstable habitat patches. In these systems, life history strategies such as long-distance dispersal, seed longevity, self-fertilisation, and reproduction from vegetative propagules are important strategies that allow plants to persist. Using two aquatic plants, Marsilea drummondii and Eleocharis acuta, we investigated the proportions of sexual and asexual reproduction and self-fertilisation by employing next-generation sequencing approaches, and we used this information to understand the population genetic structure of a large inland floodplain in western New South Wales (NSW), Australia. Asexual vegetative reproduction and self-fertilisation were more common in M. drummondii, but both species used sexual reproduction as the main mode of reproduction. This resulted in a highly differentiated genetic structure between wetlands and a similar genetic structure within wetlands. The similarity in genetic structure was influenced by the wetland in the two species, highlighting the influence of the floodplain landscape and hydrology on structuring population genetic structure. The high levels of genetic variation among wetlands and the low variation within wetlands suggests that dispersal and pollination occur within close proximity and that gene flow is restricted. This suggests a reliance on locally sourced (persistent) seed, rather than asexual (clonal) reproduction or recolonisation via dispersal, for the population maintenance of plants in dryland rivers. This highlights the importance of floodplain inundation to promote seed germination, establishment, and reproduction in dryland regions.

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41

Vilizzi, Lorenzo, Leigh A. Thwaites, Benjamin B. Smith, Jason M. Nicol y Chris P. Madden. "Ecological effects of common carp (Cyprinus carpio) in a semi-arid floodplain wetland". Marine and Freshwater Research 65, n.º 9 (2014): 802. http://dx.doi.org/10.1071/mf13163.

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Common carp, Cyprinus carpio, is a highly invasive fish species across freshwater systems of south-eastern Australia, and especially in semi-arid floodplain wetlands. However, multi-component, large-scale experimental studies on carp effects on such ecosystems are scarce. This is in spite of demands to prioritise management and control of carp for the rehabilitation of habitats across the Murray–Darling Basin. A 2-year, large-scale field experiment in a terminal wetland of the lower River Murray (South Australia) evaluated the effects of free-ranging carp on water transparency, aquatic macrophytes (biomass and cover), zooplankton density, benthic invertebrates (density, richness and diversity) as well as native fish. Within 1 year since artificial inundation, transparency sharply decreased and this was accompanied by a decrease in aquatic macrophyte biomass and cover, a fluctuation in zooplankton density, and a decrease in benthic invertebrate richness and diversity. Also, the decreases in transparency and benthic invertebrate richness were significantly related to carp biomass, which averaged 68.0 kg ha–1 and induced a shift from clear- to turbid-water state. Following a flood event, increased connectivity caused carp to further access the newly inundated areas.

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42

Jacobs, SWL, F. Perrett, GR Sainty, KH Bowmer y BJ Jacobs. "Ludwigia peruviana (Onagraceae) in the Botany Wetlands near Sydney, Australia". Marine and Freshwater Research 45, n.º 8 (1994): 1481. http://dx.doi.org/10.1071/mf9941481.

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Ludwigia peruviana is an aquatic shrubby species introduced from the Americas and spreading to wetlands in coastal south-eastem Australia. It has become dominant, replacing much of the former vegetation in the Botany Wetlands, a series of shallow urban swamps and lakes near Sydney, Australia. Studies of L. peruviana were essential to the development of a management plan for the Botany Wetlands. Ecological studies were conducted in situ and supplemented by a series of germination and growth experiments in controlled environments. Flowering peaked in early autumn. Seed production for 1990-91 was ~ 450000 seeds m-2 and there was also ~ 65000 seeds m-2 in the soil seed bank and ~ 300000 seeds m-2 in old fruits that remained on the stems over winter. The seeds are ~ 0.8 mm long, weigh ~ 0.05 mg, are hydrophobic, usually germinate while afloat, and are easily dispersed by water, machinery and birds. Viability of fresh seed was 99% (tetrazolium dye test), and - 20% of seeds were dormant. Dormancy appeared to break down within two years. Propagation and dispersal may also occur by means of stem pieces that produce new shoots. New plants from seed, seedlings or stem fragments may become established on strand lines or form floating islands that may eventually become stranded. Management needs to focus on control of the seedlings and soil seed bank.

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43

Lal, Kirti K., Carla Bonetti, Colin D. Woodroffe y Kerrylee Rogers. "Contemporary distribution of benthic foraminiferal assemblages in coastal wetlands of south-eastern Australia". Estuarine, Coastal and Shelf Science 245 (octubre de 2020): 106949. http://dx.doi.org/10.1016/j.ecss.2020.106949.

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44

Beck, Wendy, Robert Haworth y John Appleton. "Aboriginal resources change through time in New England upland wetlands, south-east Australia". Archaeology in Oceania 50 (abril de 2015): 47–57. http://dx.doi.org/10.1002/arco.5048.

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45

Bennett, William W., Kerstin Hockmann, Scott G. Johnston y Edward D. Burton. "Synchrotron X-ray absorption spectroscopy reveals antimony sequestration by reduced sulfur in a freshwater wetland sediment". Environmental Chemistry 14, n.º 6 (2017): 345. http://dx.doi.org/10.1071/en16198.

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Environmental contextAntimony is an environmental contaminant of increasing concern, due to its growing industrial usage in flame retardants, lead alloys, glass, ceramics and plastics. Here we show, using X-ray absorption spectroscopy, that antimony may be trapped in wetland sediments by reduced sulfur. This finding has implications for the management and remediation of wetlands contaminated with antimony. AbstractThe biogeochemistry of antimony (Sb) in wetland sediments is poorly characterised, despite their importance as contaminant sinks. The organic-rich, reducing nature of wetland sediments may facilitate sequestration mechanisms that are not typically present in oxic soils, where the majority of research to date has taken place. Using X-ray absorption spectroscopy (XAS), we present evidence of antimony speciation being dominated by secondary antimony–sulfur phases in a wetland sediment. Our results demonstrate that, by incorporating a newly developed SbIII–organic sulfur reference standard, linear combination fitting analysis of antimony K-edge XAS spectra and robust statistical assessment of fit quality allows the reliable discrimination of SbIII coordination environments. We found that a contaminated wetland sediment in New South Wales, Australia, contained 57% of the total antimony as SbIII–phases, with 44% present as a highly-disordered antimony phase, likely consisting of SbIII complexed by organic sulfur (e.g. thiols) or an amorphous SbIII sulfide (e.g. SbS3). The methodological approach outlined in this study and our identification of the importance of reduced sulfur in sequestering antimony has implications for future research in the area of antimony biogeochemistry, and for the management of both natural and artificial wetlands contaminated with antimony.

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46

Dobbie, Meredith Frances. "Typing Colonial Perceptions of Carrum Carrum Swamp: The Expected and the Surprising". Land 11, n.º 2 (18 de febrero de 2022): 311. http://dx.doi.org/10.3390/land11020311.

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Carrum Carrum Swamp was a vast wetland to the south-east of Melbourne, Victoria, Australia, at the time that it was first sighted by white colonists in 1803. By 1878, the colonists had commenced converting the swamp to dry land for agricultural and horticultural pursuits, and 100 years later it was predominantly residential land. Shifting values in the 1970s led to environmental concerns about water quality in local creeks and Port Phillip Bay and subsequent residential development on the former swamp included the construction of stormwater treatment wetlands. Perceptions of wetlands are now diverse, including positive perceptions that support their presence in urban settings. In contrast, traditionally, wetlands have been perceived negatively, as waste lands, leading to their drainage. Nevertheless, alternative, perhaps positive, perceptions could have existed, only to be overwhelmed by the negative perceptions driving drainage. Understanding the full range of past perceptions is important to ensure that the historical record is correct and to provide historical context to contemporary perceptions of wetlands. It will better equip natural resource managers and designers and managers of constructed wetlands in urban locations to ensure that wetlands are healthy, functioning and appreciated by their local and wider communities. Thus, the perceptions of Carrum Carrum Swamp by colonists from 1803 to 1878 were examined through qualitative content analysis of historical documents, and a typology was developed. Seven different perceptions were identified: scientific, premodern, exploitative, romantic, aesthetic, medico-mythic and ecological. Most could be traced to the colonists’ predominantly British heritage, but one perception arose in the colony in response to the specific environmental conditions that the colonists encountered. This ecological perception valued wetlands as places of predictable water supply in a land of unpredictable rainfall. It recognised wetlands as part of a broader hydrological system, with influences on the local climate. Its proponents promoted the need for a different approach to the management of wetlands than in Britain and Europe. Nevertheless, a dominant exploitative perception prevailed, leading to the drainage of Carrum Carrum Swamp. The typology developed in this study will be useful for exploring perceptions of other wetlands, both colonial and contemporary.

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47

Hopkins, Ben y John R. Argue. "Constructed “Source” Wetland Concepts Applied to Urban Landscapes". Water Science and Technology 29, n.º 4 (1 de febrero de 1994): 133–40. http://dx.doi.org/10.2166/wst.1994.0175.

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A class of wetland is introduced which employs engineering practices and installations to collect, store, dispose of, retrieve and use stormwater, at source, in the urban landscape. Two Adelaide (South Australia) examples of “source wetlands” are described. At New Brompton Estate, roof runoff from (eventually) a cluster of 15 residences is diverted to a 106 m gravel-filled trench in a central reserve. The collected water sustains a row of deciduous trees bordering the reserve and provides frequent (winter) charges, via a bore, to a Quaternary aquifer at depth 30 m. At Northfield a swale/trench system which handles all storm runoff from a residential street (including domestic contribution) will be trialled. Runoff seeping to the trench from the swale will be of high quality and will provide charges of water to a 5 m Quaternary aquifer. Some runoff of good quality will pass from the catchment in large storm events. In both cases, New Brompton and Northfield, water retrieved from the Quaternary aquifers in summer will be used for open space irrigation. Constructed source wetlands offer a valuable new option in urban stormwater quantity/quality management.

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48

Sievers, Michael. "Sand quarry wetlands provide high-quality habitat for native amphibians". Web Ecology 17, n.º 1 (19 de mayo de 2017): 19–27. http://dx.doi.org/10.5194/we-17-19-2017.

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Abstract. Anthropogenic disturbances to habitats influence the fitness of individual animals, the abundance of their populations, and the composition of their communities. Wetlands in particular are frequently degraded and destroyed, impacting the animals that inhabit these important ecosystems. The creation of wetlands during and following sand extraction processes is inevitable, and thus, sand quarries have the potential to support aquatic animals. To determine how amphibians utilise these wetlands, I conducted nocturnal call surveys at wetlands within the Kables Sands quarry, New South Wales, Australia, and within surrounding reference wetlands, and quantified levels of developmental instability (DI) as a proxy for fitness. Whilst quarry and reference wetlands were largely similar in terms of environmental characteristics, quarry wetlands consistently harboured more amphibian species and individuals. Using unsigned asymmetry as a measure of DI, frogs from the quarry sites exhibited significantly lower levels of DI compared to reference wetlands, indicating that quarry wetlands may be comparatively higher quality. Levels of DI within quarry wetlands also compared favourably to data from healthy frog populations extracted from the literature. Further enhancing the suitability of quarry wetlands would require minimal effort, with potentially significant increases in local and regional biodiversity. Documenting species presence and quantifying individual fitness by measuring limb lengths is an economically and logistically feasible method to assess the health of quarry wetlands. Overall, the methods outlined here provide a powerful, yet simple, tool to assess the overall health and suitability of quarry wetlands that could be easily adopted at quarries throughout the world.

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49

Chick, A. J. y D. S. Mitchell. "A pilot study of vertical flow wetlands at coffs harbour, New South Wales, Australia". Water Science and Technology 32, n.º 3 (1 de agosto de 1995): 103–9. http://dx.doi.org/10.2166/wst.1995.0131.

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A modular series of vertical flow wetland (VFW) systems was established in 1989/90 to treat up to 130,000 litres per day of primary settled sewage on the north coast of New South Wales, Australia as an experimental scale-up of wetland microcosms that had been developed with this hydrological format. Monitoring of inflow and outflow water quality was maintained on a weekly basis from January 1991 to February 1992. Some management parameters (e.g. flow rates) were varied during this period. Dye injection to examine hydraulic behaviour within the gravel bed was carried out on two occasions in one VFW. In general the removal of nutrients was lower than expected, with between 20% and 40% reduction in concentrations and removal of loads over the year. Suspended solids and BOD removals were excellent, with a surprisingly good reduction in faecal coliform counts as well. Reduction in flow rates improved performance markedly in all parameters.

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50

Braithwaite, LW, M. Maher, SV Briggs y BS Parker. "An Aerial Survey of 3 Game Species of Waterfowl (Family Anatidae) Populations in Eastern Australia". Wildlife Research 13, n.º 2 (1986): 213. http://dx.doi.org/10.1071/wr9860213.

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Populations of waterfowl of three game species, the Pacific black duck Anus superciliosa, grey teal A. gibberifrons, and maned duck Chenonetta jubata, were assessed by aerial survey in October 1983 within a survey region of 2 697 000 km2 of eastern Australia. The numbers of each species were assessed on all surface waters of over 1 ha, and on a sample of smaller surface waters within 10 survey bands each 30 km wide and spaced at intervals of 2� latitude from 20�30' to 38�30'S. The area within the survey bands was 324 120 km2, which gave a sampling intensity of 12.0% of the land surface area. The area of features shown as wetlands or water impoundments within the survey bands on 1 : 2 500 000 topographic maps was 19 200 km2 or 11.2% of the total area of these features in the survey region. The area of surface waters surveyed was assessed at 465 300 ha. Assessments of populations of each species were tallied for wetlands by grid cells of 6 min of 1� longitude along the survey bands (258-309 km2 depending on latitude). Distributions were then mapped, with log*10 indices of populations in each cell. Distributions of the black duck and grey teal showed a pattern of intense aggregation in limited numbers of cells, that of the maned duck was more evenly distributed. The major concentrations of the Pacific black duck were recorded in northern New South Wales and the south-eastern, western, central eastern and central coastal regions of Queensland; those of the grey teal were in south-western, western and northern New South Wales and central-eastern Queensland; the maned duck was broadly distributed over inland New South Wales with the exception of the far west, inland southern Queensland, and central northern Victoria.

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