To see the other types of publications on this topic, follow the link: Wetland ecology Australia.
Journal articles on the topic 'Wetland ecology Australia'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Wetland ecology Australia.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Boon, PI, and MA Brock. "Plants and processes in wetlands: A background." Marine and Freshwater Research 45, no. 8 (1994): 1369. http://dx.doi.org/10.1071/mf9941369.
Full textAbstract:
It is easy to gain an impression from the recent contents of Australian scientific journals dealing with ecological research that little attention is paid to the botanical ecology of Australia's inland wetlands. Less than 1% of the papers published in key Australian ecological journals over 1987-93 dealt with some aspect of the vegetation ecology of these environments. Yet over the period 1982-94 research on this topic accounted for up to 23% of the papers presented at annual conferences of the two major Australian scientific societies to which Australian limnologists are likely to belong. This discrepancy indicates that wetland vegetation is the subject of a considerable research effort by Australian limnologists, but that few of their research findings are published in refereed Australian journals. Analyses of the references cited in key review articles suggests that refereed journals outside Australia cannot account fully for the 'missing' publications: we demonstrate that much research is placed in the largely inaccessible 'grey literature' published by government departments and the like. It is also possible that some research is destined never to be published. This imbalance between the intensity of the research effort and the history of publication in Australian refereed journals prompted local scientists involved in wetland research to participate in a Special Issue dedicated to the botanical and process-oriented aspects of wetland ecology.
2
Finlayson, C. Max, Maria Grazia Bellio, and John B. Lowry. "A conceptual basis for the wise use of wetlands in northern Australia — linking information needs, integrated analyses, drivers of change and human well-being." Marine and Freshwater Research 56, no. 3 (2005): 269. http://dx.doi.org/10.1071/mf04077.
Full textAbstract:
Australia’s north supports many wetlands. The biodiversity of these wetlands is highly regarded, but many are increasingly being affected by well recognised pressures that result in adverse change in their ecological character. The extent of the knowledge base and causes of adverse change in Australia’s tropical wetlands are reviewed with an emphasis on the linkage between direct and indirect drivers of change. Within the context of the existing knowledge base, an integrated model for collecting information on the ecological character of tropical wetlands is proposed. The model encompasses hierarchical and multi-scalar approaches to wetland inventory, assessment and monitoring and was developed largely from research undertaken in northern Australia. It is based around the concepts of wise use and maintenance of the ecological character of wetlands, which in turn emphasises the value of wetlands to people through the delivery of ecosystem services. A broader conceptual framework linking ecosystem services and human well-being to the condition of wetlands is introduced as a forerunner to considering research needs for tropical Australian wetlands. The integrated model and framework entail community consultation and the involvement of stakeholders in decisions about wetland research and management. In conclusion, it is emphasised that the maintenance of the ecological character of the wetlands of northern Australia is a task for wetland managers, users and owners in collaboration with scientists from many disciplines.
3
Halse, SA, MR Williams, RP Jaensch, and JAK Lane. "Wetland characteristics and waterbird use of wetlands in south-western Australia." Wildlife Research 20, no. 1 (1993): 103. http://dx.doi.org/10.1071/wr9930103.
Full textAbstract:
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.
4
Fensham, R. J., R. J. Fairfax, D. Pocknee, and J. Kelley. "Vegetation patterns in permanent spring wetlands in arid Australia." Australian Journal of Botany 52, no. 6 (2004): 719. http://dx.doi.org/10.1071/bt04043.
Full textAbstract:
A transect-based quadrat survey was conducted within 11 spring wetlands fed by permanent groundwater flows from the Great Artesian Basin at Elizabeth Springs in western Queensland. Flow patterns within individual wetlands change with sedimentation associated with mound building, siltation of abandoned drains and changes in aquifer pressure associated with artificial extraction from bores. The pattern of floristic groups for the wetland quadrats was poorly related to soil texture, water pH, slope and topographic position. Patterns were most clearly related to wetland age as determined from aerial photography, with a clear successional sequence from mono-specific stands of Cyperus laevigatus on newly formed wetland areas to more diverse wetland assemblages. However, evidence from other Great Artesian Basin springs suggests that succession can also result in reduced species richness where the palatable tall reed Phragmites australis develops mono-specific stands.
5
Maher, MT, and LW Braithwaite. "Patterns of waterbird use in wetlands of the Paroo, A river system of inland Australia." Rangeland Journal 14, no. 2 (1992): 128. http://dx.doi.org/10.1071/rj9920128.
Full textAbstract:
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.
6
T. Kingsford, Richard, Rachael F. Thomas, and Alison L. Curtin. "Conservation of wetlands in the Paroo and Warrego River catchments in arid Australia." Pacific Conservation Biology 7, no. 1 (2001): 21. http://dx.doi.org/10.1071/pc010021.
Full textAbstract:
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.
7
Chadhokar, Yojana, and Lynette C. McLaughlin. "Interpretation at Wetland Sites in the Sydney Region." Journal of Interpretation Research 4, no. 1 (April 1999): 39–57. http://dx.doi.org/10.1177/109258729900400104.
Full textAbstract:
Interpretation of wetland issues and values for the broader community, as well as for students, is regarded as an important strategy toward achieving better wetland management, reversing past degradation, and halting wetland loss along the east coast of Australia, where population pressure has heavily affected these systems. This paper presents the results of a review of interpretive and educational facilities and programs at five wetland sites across the Sydney region to gain a regional perspective on the provision of wetland education and interpretation of wetland ecology and conservation. This review considered goals, range of facilities and programs, wetland themes covered for the general public and in formal educational programs, and evaluation methods. The results are discussed in light of the overall goal of wetland conservation and more detailed goals at individual sites. Goals were found to focus primarily on “public awareness” of wetlands, a goal inadequate to meet the broader goal of long-term protection and conservation. At sites most accessible to the majority of the Sydney population, a considerable discrepancy existed between the aspects of wetland ecology and management presented to school groups and those presented to the general public, making it difficult to meet even the goal of public awareness.
8
Finlayson, C. M., S. J. Capon, D. Rissik, J. Pittock, G. Fisk, N. C. Davidson, K. A. Bodmin, et al. "Policy considerations for managing wetlands under a changing climate." Marine and Freshwater Research 68, no. 10 (2017): 1803. http://dx.doi.org/10.1071/mf16244.
Full textAbstract:
Drawing on the experience and lessons of wetland researchers and managers in Australia and New Zealand, we examined the implications of climate change for wetland policy and management, and identified potential adaptation responses and the information needed to support these. First, we considered wetland vulnerability to climate change, focusing on wetland exposure and sensitivity. We then outlined the existing policy context for dealing with climate change, with an emphasis on the Ramsar Convention on Wetlands. We then considered how the objectives and targets for wetland management can be set in the face of climate change, how management can be adapted to climate change given the uncertainties involved, and how we can monitor and evaluate wetland condition in the face of climate change. We concluded with a set of principles to guide adaptation of wetland conservation and management policy to climate change.
9
Ralph, Timothy J., Paul P. Hesse, and Tsuyoshi Kobayashi. "Wandering wetlands: spatial patterns of historical channel and floodplain change in the Ramsar-listed Macquarie Marshes, Australia." Marine and Freshwater Research 67, no. 6 (2016): 782. http://dx.doi.org/10.1071/mf14251.
Full textAbstract:
In the context of static conservation reserves, dynamic fluvial processes and patterns of river channel and floodplain change are problematic for environmental management. Floodplain wetlands that evolve by erosion and sedimentation experience changes in the location and extent of channels and wetlands regardless of conservation reserve boundaries. We describe historical channel and floodplain change in an Australian wetland of international ecological significance, the southern Macquarie Marshes, and synthesise the role of avulsion in wetlands that move laterally on the broader floodplain. Avulsion has shifted the foci of flooding and areas of aquatic habitat in the system over the last century. By ~1925, active wetlands surrounding the Old Macquarie River and the original conservation area contracted around Monkeygar Creek within the present nature reserve, and the boundary of this reserve has changed little since the 1940s. Ecological changes associated with continued wetland desiccation in the reserve triggered a recent Ramsar Article 3.2 notification for the Macquarie Marshes, prompting management responses from government agencies. Fluvial morphodynamics and their impacts on wetland ecology should be specifically recognised and integrated with adaptive management plans to combine new findings with lessons learned from previous intervention strategies for the long-term ecological sustainability of floodplain wetlands.
10
Wrigley, TJ, SW Rolls, and JA Davis. "Limnological features of coastal-plain wetlands on the Gnangara Mound, Perth, Western Australia." Marine and Freshwater Research 42, no. 6 (1991): 761. http://dx.doi.org/10.1071/mf9910761.
Full textAbstract:
The Gnangara Mound is an area of elevated sandy soil on the Swan Coastal Plain to the north of Perth. It constitutes a major groundwater resource for metropolitan Perth. Sixteen wetlands on the Mound had total phosphorus concentrations of 12-462�g L-1, the high values being attributed to agricultural and urban activity. Sediment concentrations of total phosphorus and total nitrogen were 61-954 and 1212-16739 �g g-1, respectively. Conductivities were 505-10270 �S cm-1, and pH values were 3.3-9.3. Only one wetland was highly coloured (79.9 8440 m-1), with an E4/E6 ratio of 4.6. Chlorophyll a concentrations were 0.01-130.8�g L-1; in wetlands with low gilvin concentrations, Myxophyceae dominated, whereas wetlands with higher gilvin concentrations had large numbers of diatoms and Chlorophyceae. The highly coloured wetland had the lowest chlorophyll a concentration despite high nutrient concentrations, supporting the hypothesis that the consequent reduction in light or other associated factors are important in maintaining low phytoplankton biomass in dystrophic wetlands of the region, particularly those on Bassendean sands.
11
Finlayson, C. Max. "Wetland research and management in the Kakadu region of northern Australia." Marine and Freshwater Research 69, no. 7 (2018): 1007. http://dx.doi.org/10.1071/mf18158.
Full textAbstract:
This paper provides an introduction to the ecological features that characterise the wetlands of the Kakadu region in northern Australia and places these in a wider context for other papers in a special issue that expands on these features. The special issue aims to (1) synthesise knowledge of the ecosystem process that underpins the management of the rivers and floodplains and (2) undertake an integrated assessment so as to evaluate alternative management responses in the face of an uncertain future. These aims are addressed in individual papers. The managerial and physical settings of the region are introduced before some of the previous wetland research is summarised and gaps in information considered. The gaps included an understanding of the relationship between the provision of ecosystem services and outcomes for water quality and biodiversity, and ecosystem and population dynamics of wetland biodiversity. In a conclusion, the occurrence and acceptance or management of invasive species is considered in terms of the emergence of novel ecosystems as a consequence of global change, in particular sea-level rise and anticipated transition of freshwater wetlands to saline conditions.
12
Whalley, R. D. B., J. N. Price, M. J. Macdonald, and 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, no. 2 (2011): 109. http://dx.doi.org/10.1071/rj11002.
Full textAbstract:
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.
13
Ling, J. E., M. T. Casanova, I. Shannon, and M. Powell. "Development of a wetland plant indicator list to inform the delineation of wetlands in New South Wales." Marine and Freshwater Research 70, no. 3 (2019): 322. http://dx.doi.org/10.1071/mf18114.
Full textAbstract:
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.
14
Jeffrey, Luke C., Damien T. Maher, Scott G. Johnston, Kylie Maguire, Andrew D. L. Steven, and Douglas R. Tait. "Rhizosphere to the atmosphere: contrasting methane pathways, fluxes, and geochemical drivers across the terrestrial–aquatic wetland boundary." Biogeosciences 16, no. 8 (April 29, 2019): 1799–815. http://dx.doi.org/10.5194/bg-16-1799-2019.
Full textAbstract:
Abstract. Although wetlands represent the largest natural source of atmospheric CH4, large uncertainties remain regarding the global wetland CH4 flux. Wetland hydrological oscillations contribute to this uncertainty, dramatically altering wetland area, water table height, soil redox potentials, and CH4 emissions. This study compares both terrestrial and aquatic CH4 fluxes in permanent and seasonal remediated freshwater wetlands in subtropical Australia over two field campaigns, representing differing hydrological and climatic conditions. We account for aquatic CH4 diffusion and ebullition rates and plant-mediated CH4 fluxes from three distinct vegetation communities, thereby examining diel and intra-habitat variability. CH4 emission rates were related to underlying sediment geochemistry. For example, distinct negative relationships between CH4 fluxes and both Fe(III) and SO42- were observed. Where sediment Fe(III) and SO42- were depleted, distinct positive trends occurred between CH4 emissions and Fe(II) ∕ acid volatile sulfur (AVS). Significantly higher CH4 emissions (p < 0.01) in the seasonal wetland were measured during flooded conditions and always during daylight hours, which is consistent with soil redox potential and temperature being important co-drivers of CH4 flux. The highest CH4 fluxes were consistently emitted from the permanent wetland (1.5 to 10.5 mmol m−2 d−1), followed by the Phragmites australis community within the seasonal wetland (0.8 to 2.3 mmol m−2 d−1), whilst the lowest CH4 fluxes came from a region of forested Juncus spp. (−0.01 to 0.1 mmol m−2 d−1), which also corresponded to the highest sedimentary Fe(III) and SO42-. We suggest that wetland remediation strategies should consider geochemical profiles to help to mitigate excessive and unwanted methane emissions, especially during early system remediation periods.
15
Lowe, Katrin, J. Guy Castley, and Jean-Marc Hero. "Resilience to climate change: complex relationships among wetland hydroperiod, larval amphibians and aquatic predators in temporary wetlands." Marine and Freshwater Research 66, no. 10 (2015): 886. http://dx.doi.org/10.1071/mf14128.
Full textAbstract:
Amphibians that utilise temporary wetlands with unpredictable hydrology are living on the edge, maintaining viable populations under variable climatic conditions. Information on their breeding ecology will provide insight into their adaptive capacity and resilience to climate change. The environmental factors influencing breeding of a temporary wetland breeding frog (Litoria olongburensis) from eastern Australia were examined over two breeding seasons from August 2009 to March 2011. The influence of biotic and abiotic wetland characteristics on the abundance and seasonality of L. olongburensis aquatic larvae was quantified throughout the latitudinal range of the species. Substantial variation in yearly precipitation resulted in changes to the timing of breeding, and patterns of tadpole and predator abundance, which also varied along a hydroperiod gradient. Litoria olongburensis displayed adaptive strategies, including breeding when hydrological conditions were likely to last longest, and short time to hatching and metamorphosis. Concentrating breeding efforts early during wetland filling coincided with low predator densities. These pre-adaptations may reflect an adaptive capacity to predicted changes in frequency and reliability of precipitation as a result of climate change, and may apply to other temporary wetland species. Their conservation depends on preserving wetlands with a variety of hydroperiods within a landscape matrix.
16
Halford, J. J., and R. J. Fensham. "Vegetation and environmental relations of ephemeral subtropical wetlands in central Queensland, Australia." Australian Journal of Botany 62, no. 6 (2014): 499. http://dx.doi.org/10.1071/bt14115.
Full textAbstract:
An extensive network of ephemeral wetlands exists within arid and semiarid Australia. These wetlands provide important resources to local and migratory species; however, they are poorly studied, particularly in terms of their vegetation–environmental relations. To better understand these relationships, a flora survey was conducted in a large complex of ephemeral, subtropical wetlands in central Queensland, in an attempt to describe the vegetation patterns present, and determine their underlying environmental conditions. In total, eight vegetation groups were identified, with water depth having the greatest influence over vegetation patterns, with slope, assumed to affect drainage, having a secondary influence. Aquatics, such as Nymphaea gigantea Hook. and Vallisneria nana R.Br., characterise the deepest zone, grasslands and sedgelands characterise intermediate depths and a herbfield including many ephemeral terrestrial species characterises the shallow zone. The geography of the wetland-dependant species indicates mostly tropical affinities. All wetland-dependant species present are broadly distributed, with none requiring special conservation considerations. There are no significant infestations of exotic species, including ponded pasture species, that have spread throughout other tropical and subtropical wetlands. The complex of wetlands extending over a large catchment area in the upper Dawson River catchment is in excellent natural condition, and as such, it forms a very important component of the network of wetlands extending along the east coast of Australia.
17
Douglas, Michael M., Stuart E. Bunn, and Peter M. Davies. "River and wetland food webs in Australia's wet - dry tropics: general principles and implications for management." Marine and Freshwater Research 56, no. 3 (2005): 329. http://dx.doi.org/10.1071/mf04084.
Full textAbstract:
The tropical rivers of northern Australia have received international and national recognition for their high ecological and cultural values. Unlike many tropical systems elsewhere in the world and their temperate Australian counterparts, they have largely unmodified flow regimes and are comparatively free from the impacts associated with intensive land use. However, there is growing demand for agricultural development and existing pressures, such as invasive plants and feral animals, threaten their ecological integrity. Using the international literature to provide a conceptual framework and drawing on limited published and unpublished data on rivers in northern Australia, we have derived five general principles about food webs and related ecosystem processes that both characterise tropical rivers of northern Australia and have important implications for their management. These are: (1) the seasonal hydrology is a strong driver of ecosystem processes and food-web structure; (2) hydrological connectivity is largely intact and underpins important terrestrial–aquatic food-web subsidies; (3) river and wetland food webs are strongly dependent on algal production; (4) a few common macroconsumer species have a strong influence on benthic food webs; and (5) omnivory is widespread and food chains are short. The implications of these ecosystem attributes for the management and protection of tropical rivers and wetlands of northern Australian are discussed in relation to known threats. These principles provide a framework for the formation of testable hypotheses in future research programmes.
18
Lind, P. R., B. J. Robson, B. D. Mitchell, and T. G. Matthews. "Can sand slugs in rivers deliver conservation benefits? The biodiversity value of tributary junction plug wetlands in the Glenelg River, Australia." Marine and Freshwater Research 60, no. 5 (2009): 426. http://dx.doi.org/10.1071/mf08175.
Full textAbstract:
Restoration works are carried out to alleviate human impacts and improve habitats within ecosystems. However, human impacts may also create new (anthropogenic) habitat for species to exploit. A dilemma arises when proposed restoration works would remove anthropogenic habitat and the assemblages it supports. Sediment input into the Glenelg River has formed tributary junction plug wetlands at confluences. Sand slug removal is proposed as part of river rehabilitation, but would also drain plug wetlands. We sampled four plug wetland, four river run and three river pool sites to determine whether plug wetlands influence water quality and add to the biodiversity of macroinvertebrates in the Glenelg River. Water quality and macroinvertebrate diversity were similar in plug wetlands, river runs and river pools. Assemblages were distinct among all sites, regardless of type, so there was no characteristic ‘plug-wetland fauna’. Therefore, although removal of plug wetlands would not cause a dramatic loss of invertebrate biodiversity, it would destroy anthropogenic habitat that supports a similar range of species to natural habitats in a river subject to multiple degrading processes. Gains from rehabilitation should be weighed against the value of anthropogenic habitat and the extent of similar habitat lost elsewhere in the ecosystem.
19
Kattel, Giri R., Xuhui Dong, and Xiangdong Yang. "A century-scale, human-induced ecohydrological evolution of wetlands of two large river basins in Australia (Murray) and China (Yangtze)." Hydrology and Earth System Sciences 20, no. 6 (June 3, 2016): 2151–68. http://dx.doi.org/10.5194/hess-20-2151-2016.
Full textAbstract:
Abstract. Recently, the provision of food and water resources of two of the world's largest river basins, the Murray and the Yangtze, has been significantly altered through widespread landscape modification. Long-term sedimentary archives, dating back for some centuries from wetlands of these river basins, reveal that rapid, basin-wide development has reduced the resilience of biological communities, resulting in considerable decline in ecosystem services, including water quality. Large-scale human disturbance to river systems, due to river regulation during the mid-20th century, has transformed the hydrology of rivers and wetlands, causing widespread modification of aquatic biological communities. Changes to cladoceran zooplankton (water fleas) were used to assess the historical hydrology and ecology of three Murray and Yangtze river wetlands over the past century. Subfossil assemblages of cladocerans retrieved from sediment cores (94, 45, and 65 cm) of three wetlands: Kings Billabong (Murray), Zhangdu, and Liangzi lakes (Yangtze), showed strong responses to hydrological changes in the river after the mid-20th century. In particular, river regulation caused by construction of dams and weirs together with river channel modifications, has led to significant hydrological alterations. These hydrological disturbances were either (1) a prolonged inundation of wetlands or (2) reduced river flow, both of which caused variability in wetland depth. Inevitably, these phenomena have subsequently transformed the natural wetland habitats, leading to a switch in cladoceran assemblages to species preferring poor water quality, and in some cases to eutrophication. The quantitative and qualitative decline of wetland water conditions is indicative of reduced ecosystem services, and requires effective restoration measures for both river basins which have been impacted by recent socioeconomic development and climate change.
20
Ryder, DS, and P. Horwitz. "Seasonal water regimes and leaf litter processing in a wetland on the Swan Coastal Plain, Western Australia." Marine and Freshwater Research 46, no. 7 (1995): 1077. http://dx.doi.org/10.1071/mf9951077.
Full textAbstract:
The effect of seasonal or permanent inundation on the processing of leaf litter from two emergent macrophytes, Baumea articulata and Typha orientalis, was examined at Lake Jandabup, a seasonal wetland on the Swan Coastal Plain. Leaf litter processing was quantified through the loss of organic matter from leaf packs. The contribution made by microorganisms was also examined. Leaf packs exposed to seasonal inundation had significantly higher losses of organic matter after six months than did those permanently inundated, with B. articulata leaf packs losing significantly more. The presence of a diurnally stratified water column in permanently inundated sites in summer, resulting in reduced oxygen concentrations at the bottom of the water column, may be responsible for lower organic matter loss in this environment. These results are supported by the presence of organic-rich soils at permanently inundated sites and their absence at seasonally inundated sites, indicating a long-term pattern of leaf litter processing and wetland water regimes. The distribution of organic-rich soils in wetland basins may provide an indication of long-term water level regimes and can therefore provide a valuable tool for determining water regimes in artificially maintained or restored wetlands.
21
Adame, M. F., H. Franklin, N. J. Waltham, S. Rodriguez, E. Kavehei, M. P. Turschwell, S. R. Balcombe, P. Kaniewska, M. A. Burford, and M. Ronan. "Nitrogen removal by tropical floodplain wetlands through denitrification." Marine and Freshwater Research 70, no. 11 (2019): 1513. http://dx.doi.org/10.1071/mf18490.
Full textAbstract:
Excess nitrogen (N) leading to the eutrophication of water and impacts on ecosystems is a serious environmental challenge. Wetlands can remove significant amounts of N from the water, primarily through the process of denitrification. Most of our knowledge on wetland denitrification is from temperate climates; studies in natural tropical wetlands are very scarce. We measured denitrification rates during a dry and a wet season in five floodplain forests dominated by Melaleuca spp., a coastal freshwater wetland of tropical Australia. We hypothesised that the denitrification potential of these wetlands would be high throughout the year and would be limited by N and carbon (C) availability. Mean potential denitrification rates (Dt) were 5.0±1.7mgm2h–1, and were within the reported ranges for other tropical and temperate wetlands. The rates of Dt were similar between the dry and the wet seasons. From the total unamended denitrification rates (Dw, 3.1±1.7mgm2h–1), 64% was derived from NO3– of the water column and the rest from coupled nitrification–denitrification. The factor most closely associated with denitrification was background water NO3–-N concentrations. Improved management and protection of wetlands could play an important role in improving water quality in tropical catchments.
22
Han, Jiaqi, Dongyan Wang, and Shuwen Zhang. "Momoge Internationally Important Wetland: Ecosystem Integrity Remote Assessment and Spatial Pattern Optimization Study." Land 11, no. 8 (August 18, 2022): 1344. http://dx.doi.org/10.3390/land11081344.
Full textAbstract:
Along the migration route between East Asia and Australia, numerous migratory birds use the Momoge Internationally Important Wetland as a habitat. Human activities and climate variability cause salinization and meadowization. We developed the “Quality-Pressure-Pattern-Service” remote assessment framework for ecosystem integrity, using a three level approach (TLA). The model was used to assess ecosystem integrity, identify improper wetland development, and provide spatial optimization strategies. The research region was dominated by wetlands, followed by dry fields. Wetlands continued to decrease between 1965 and 2019, as arable land and construction land continued to increase. Over the course of 54 years, ecosystem integrity declined. In 2019, around half of the areas had poor or extremely poor ecosystem integrity. Because the eastern study area contained many pristine inland beaches, the eastern study area displayed greater ecosystem integrity than the central and western areas. Priority should therefore be given to wetland restoration in the HJ core area (one of the three core areas of the reserve), where most of the herb marsh has been converted to arable land. This study revealed the integrity and authenticity of wetland ecosystems. Our results can aid in the protection of wetland habitats, encourage sustainable development, and help in the building of a national park in northeastern China.
23
Kattel, G. R., X. Dong, and X. Yang. "A century scale human-induced hydrological and ecological changes of wetlands of two large river basins in Australia (Murray) and China (Yangtze): development of an adaptive water resource management framework." Hydrology and Earth System Sciences Discussions 12, no. 8 (August 24, 2015): 8247–87. http://dx.doi.org/10.5194/hessd-12-8247-2015.
Full textAbstract:
Abstract. Recently, the provision of food and water resources of two of the world's large river basins, the Murray and the Yangtze, has been significantly altered through widespread landscape modification. Long-term sedimentary archives, dating back to past centuries, from wetlands of these river basins reveal that rapid, basin-wide development has reduced resilience of biological communities, resulting in considerable decline in ecosystem services, including water quality. In particular, large-scale human disturbance to river systems, due to river regulation during the mid-20th century, has transformed the hydrology of rivers and wetlands, causing widespread disturbance to aquatic biological communities. Historical changes of cladoceran zooplankton (water fleas) were used to assess the hydrology and ecology of three Murray and Yangtze River wetlands over the past century. Subfossil assemblages of cladocerans retrieved from sediment cores (94, 45 and 65 cm) of three wetlands: Kings Billabong (Murray), Zhangdu and Liangzi Lakes (Yangtze) strongly responded to hydrological changes of the river after the mid-20th century. River regulation caused by construction of dams and weirs, and river channel modifications has led to hydrological alterations. The hydrological disturbances were either: (1) a prolonged inundation of wetlands, or (2) reduced river flow, which caused variability in wetland depth. These phenomena subsequently transformed the natural wetland habitats, leading to a switch in cladoceran assemblages preferring poor water quality and eutrophication. An adaptive water resource management framework for both of these river basins has been proposed to restore or optimize the conditions of wetland ecosystems impacted by 20th century human disturbance and climate change.
24
Kingsford, R. T., P. S. Wong, L. W. Braithwaite, and M. T. Maher. "Waterbird abundance in eastern Australia, 1983 - 92." Wildlife Research 26, no. 3 (1999): 351. http://dx.doi.org/10.1071/wr96062.
Full textAbstract:
We examined the relationships between abundance of 16 species of waterbirds and the rainfall in eastern Australia, the rainfall west of this region, the annual Southern Oscillation index (SOI), the wetland area, and hunting in eastern Australia for the period 1983–92. Data were collected during aerial surveys of eastern Australia. For most explanatory variables, lags of up to five years before aerial surveys were also investigated during these analyses. The analyses covered all nine game species (plumed whistling-duck, Australian shelduck, Australian wood duck, pink-eared duck, grey teal, chestnut teal, Pacific black duck, Australasian shoveler, hardhead) and seven non-game species (Australian pelican, white-faced heron, yellow-billed spoonbill, freckled duck, black swan, black-winged stilt, red-necked avocet). Regression models were developed for all species apart from Australian pelicans. Rainfall and climate indices generally were most correlated with the species’ abundance. Bonferroni adjustments to significance levels meant that there were significant variables in regression models for seven of the 16 species. Abundance indices for plumed whistling-duck, chestnut teal, hardhead, black swan and black-winged stilt were related to the climate variables (rainfall, SOI) and wetland area, whereas abundance of pink-eared duck and red-necked avocets were negatively related. Abundance of chestnut teal was positively related to numbers of hunting licences sold. The results are equivocal about the role of hunting in determining waterfowl abundance, which is probably a reflection of few data points and numbers of variables included. In general, abundance indices of waterbirds appear to have decreased between 1983 and 1992, which may correspond to other factors not modelled
25
Stokeld, Danielle, Andrew J. Hamer, Rodney van der Ree, Vincent Pettigrove, and Graeme Gillespie. "Factors influencing occurrence of a freshwater turtle in an urban landscape: a resilient species?" Wildlife Research 41, no. 2 (2014): 163. http://dx.doi.org/10.1071/wr13205.
Full textAbstract:
Context Species vary broadly in their ability to adapt to urbanisation. Freshwater turtles are vulnerable to the loss and degradation of terrestrial and aquatic habitat in urban environments. There have been few publications investigating impacts of urbanisation on freshwater turtles in Australia. Aims We investigated the effects of urbanisation on the distribution and abundance of the eastern long-necked turtle (Chelodina longicollis) in greater Melbourne. Methods We examined occurrence and relative abundance of C. longicollis at 55 wetlands across an urban–rural gradient in relation to site- and landscape-level factors. Occupancy was modelled using the program PRESENCE, and incorporated landscape and habitat covariates. A negative binomial regression model was used to examine the influence of landscape and habitat factors on relative abundance by using WinBUGS. Key results C. longicollis occupied 85% of the 55 wetlands we surveyed, and we found no evidence that wetland occupancy was influenced by the variables we measured. However, relative abundance was highest at wetlands with low water conductivity and heavy metal pollution, and in wetlands furthest from rivers. Conclusions C. longicollis appears to be resilient to urbanisation and is likely to persist in urban landscapes, possibly because of the creation of new wetlands in Australian cities. However, long-term studies focussed on demographic parameters, or survivorship, may elucidate as yet undetected effects of urbanisation. Although no specific management recommendations may be necessary for C. longicollis in urban areas at this time, this species may be in decline in non-urban areas as a result of climatic changes and wetland drying. Implications Our findings suggest that caution is required before drawing generalised conclusions on the impacts of urbanisation on turtles, as the effects are likely to be species-specific, dependent on specific ecology and life-history requirements. Further studies are required to ascertain these relationships for a wider array of species and over longer time spans.
26
Mackenzie, Lydia, Henk Heijnis, Patricia Gadd, Patrick Moss, and James Shulmeister. "Geochemical investigation of the South Wellesley Island wetlands: Insight into wetland development during the Holocene in tropical northern Australia." Holocene 27, no. 4 (September 28, 2016): 566–78. http://dx.doi.org/10.1177/0959683616670219.
Full textAbstract:
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.
27
Duke, Norman C., Colin Field, Jock R. Mackenzie, Jan-Olaf Meynecke, and Apanie L. Wood. "Rainfall and its possible hysteresis effect on the proportional cover of tropical tidal-wetland mangroves and saltmarsh–saltpans." Marine and Freshwater Research 70, no. 8 (2019): 1047. http://dx.doi.org/10.1071/mf18321.
Full textAbstract:
Mangrove–saltmarsh tidal wetlands are highly dynamic ecosystems, responding and adapting to climate and physical conditions at all spatial and temporal scales. Knowledge of the large-scale ecosystem processes involved and how they might be influenced by climate variables is highly relevant today. For tidal-wetland sites well within the latitudinal range of the mostly tropical mangrove communities, we confirm that average annual rainfall influences vegetative cover, as well as species composition and biomass of tidal wetlands. On the basis of 205 largely unmodified, tropical and subtropical estuaries of northern Australia, a sigmoidal relationship, with a centroid inflection point ~1368mm, was derived between rainfall and the relative amounts of high-biomass mangroves and low-biomass saltmarsh–saltpan vegetation. The presence and probability of observed combinations of these community types were quantified using the wetland cover index, which is the ratio of total mangrove area to that of mangroves plus intertidal saltmarsh and saltpans. Accordingly, periodic changes in rainfall trends are likely manifest as either encroachment or dieback of mangroves along the ecotones separating them from tidal saltmarsh–saltpans. Presented is a new conceptual framework and model that describes how such ecosystem-scale processes take place in tropical and subtropical tidal wetlands.
28
Lyon, Jarod, Ivor Stuart, David Ramsey, and 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, no. 3 (2010): 271. http://dx.doi.org/10.1071/mf08246.
Full textAbstract:
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.
29
Pressey, R. L., and P. Adam. "A review of wetland inventory and classification in Australia." Vegetatio 118, no. 1-2 (June 1995): 81–101. http://dx.doi.org/10.1007/bf00045192.
Full text
30
Boys, Craig A., and Bruce Pease. "Opening the floodgates to the recovery of nektonic assemblages in a temperate coastal wetland." Marine and Freshwater Research 68, no. 6 (2017): 1023. http://dx.doi.org/10.1071/mf15445.
Full textAbstract:
Tidally active wetlands are important nurseries for fish and crustaceans; however, urban development involving structural flood mitigation has fragmented and destroyed much of this habitat, often leading to losses in fisheries productivity. The present study demonstrated that some of these impacts may be reversible if rehabilitation projects are implemented over a sufficiently long time. The incremental opening of eight floodgates at a temperate coastal wetland in Australia afforded the opportunity to monitor water quality and nekton assemblages in a tidal creek over 11 years, encompassing pre-floodgate opening, opening of one gate, three gates and finally all eight gates. Floodgate opening enhanced both water quality and nektonic assemblages relative to a control creek whose barrier remained in place. A doubling in species richness occurred and many commercially important species increased in abundance, including Metapenaeus macleayi (15 times more), Acanthopagrus australis (62 times more), Liza argentea (10 times more) and Gerres subfasciatus (19 times more). Recovery to a condition similar to unrestricted reference creeks was achieved once all eight gates were opened. The study illustrated that reinstating tidal flushing can recover nursery habitats and enhance populations of economically valuable species.
31
Vilizzi, Lorenzo, Leigh A. Thwaites, Benjamin B. Smith, Jason M. Nicol, and Chris P. Madden. "Ecological effects of common carp (Cyprinus carpio) in a semi-arid floodplain wetland." Marine and Freshwater Research 65, no. 9 (2014): 802. http://dx.doi.org/10.1071/mf13163.
Full textAbstract:
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.
32
Arnold, T. N., and C. E. Oldham. "Trace-element contamination of a shallow wetland in Western Australia." Marine and Freshwater Research 48, no. 6 (1997): 531. http://dx.doi.org/10.1071/mf96088.
Full textAbstract:
The arsenic, chromium, iron and lead contamination of sediments in Lake Yangebup was investigated, focussing on the potential for arsenic to be remobilized during resuspension of contaminated sediments. Despite a distinct source of arsenic, chromium and iron on one shore, horizontal trends in sediment concentrations were weak. Lead concentrations were homogeneous. This indicated a continual remobilization of these trace elements through the lake; a likely mechanism in such a shallow lake is resuspension of bottom sediments. An arsenic maximum was found 10 cm below the surface of the sediment in a settled flocculant layer that predominantly comprised decaying plankton. Remobilization of arsenic from this layer during resuspension was simulated with elutriate tests under both oxic and anoxic conditions. Under oxic conditions, the amount of arsenic released was correlated to the initial concentrations of sediment arsenic, indicating that porewater was the source of arsenic. However, in the anoxic experiments, no such correlations were evident, suggesting that biological or chemical processes were interfering with the redox potential and thus with the release of arsenic. Processes such as stratification, oxygen depletion and reaeration, desorption and adsorption in this shallow lake interact on timescales shorter than those that dominate contaminant cycling in deeper water bodies.
33
Halse, S. A., J. K. Ruprecht, and A. M. Pinder. "Salinisation and prospects for biodiversity in rivers and wetlands of south-west Western Australia." Australian Journal of Botany 51, no. 6 (2003): 673. http://dx.doi.org/10.1071/bt02113.
Full textAbstract:
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.
34
Froend, RH, and AJ McComb. "Distribution, productivity and reproductive phenology of emergent macrophytes in relation to water regimes at wetlands of south-western Australia." Marine and Freshwater Research 45, no. 8 (1994): 1491. http://dx.doi.org/10.1071/mf9941491.
Full textAbstract:
Variability in the response of Baumea articulata and Typha orientalis to water regime was assessed at eight urban wetland lakes on the Swan Coastal Plain, south-western Australia. Distribution, productivity and reproduction along water regime gradients were assessed, and the importance of wetland nutrient status in altering plant response to water regime was also considered. The overall range in distribution observed across the lakes was similar for both species, but there was significant between-lake variation in distribution relative to mean water depth. Neither species occupied its full 'potential' distribution range, relative to water regime, at any one wetland. Standing biomass and ramet and inflorescence densities varied along the water regime gradient, with peak values generally occurring at intermediate water depths. There was a shift in phenology (ramet emergence, new leaf growth, flowering and seed production) with increasing mean water depth and nutrient status. Seasonal values of aboveground productivity changed along the water regime gradient for both species. Comparison of productivity at sampling points of different nutrlent status but similar water regime showed a significantly greater growth response in T. orientalis compared with B. articulata. The significance of these results to urban wetland management is discussed.
35
Kelleway, Jeff, Debashish Mazumder, G. Glenn Wilson, Neil Saintilan, Lisa Knowles, Jordan Iles, and Tsuyoshi Kobayashi. "Trophic structure of benthic resources and consumers varies across a regulated floodplain wetland." Marine and Freshwater Research 61, no. 4 (2010): 430. http://dx.doi.org/10.1071/mf09113.
Full textAbstract:
Riverine food webs are often laterally disconnected (i.e. between watercourses) in regulated floodplain wetlands for prolonged periods. We compared the trophic structure of benthic resources and consumers (crustaceans and fish) of the three watercourses in a regulated floodplain wetland (the Gwydir Wetlands, Australia) that shared the same source water but were laterally disconnected. The crustaceans Cherax destructor (yabby), Macrobrachium australiense (freshwater prawn), the exotic fish Cyprinus carpio (European carp) and Carassius auratus (goldfish) showed significantly different δ13C values among the watercourses, suggesting spatial differences in primary carbon sources. Trophic positions were estimated by using δ15N values of benthic organic matter as the base of the food web in each watercourse. The estimated trophic positions and gut contents showed differences in trophic positions and feeding behaviours of consumers between watercourses, in particular for Melanotaenia fluviatilis (Murray–Darling rainbowfish) and M. australiense. Our findings suggest that the observed spatial variation in trophic structure appears to be largely related to the spatial differences in the extent and type of riparian vegetation (i.e. allochthonous carbon source) across the floodplain that most likely constituted part of the benthic resources.
36
Mackenzie, Lydia, Patrick Moss, and Sean Ulm. "A late-Holocene record of coastal wetland development and fire regimes in tropical northern Australia." Holocene 30, no. 10 (June 16, 2020): 1379–90. http://dx.doi.org/10.1177/0959683620932970.
Full textAbstract:
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.
37
Saintilan, Neil, and Kerrylee Rogers. "The significance and vulnerability of Australian saltmarshes: implications for management in a changing climate." Marine and Freshwater Research 64, no. 1 (2013): 66. http://dx.doi.org/10.1071/mf12212.
Full textAbstract:
We review the distribution, status and ecology of Australian saltmarshes and the mechanisms whereby enhanced atmospheric carbon dioxide and associated climate change have influenced and will influence the provision of ecosystem goods and services. Research in temperate and subtropical saltmarsh has demonstrated important trophic contributions to estuarine fisheries, mediated by the synchronised mass-spawning of crabs, which feed predominantly on the C4 saltmarsh grass Sporobolus virginicus and microphytobenthos. Saltmarshes also provide unique feeding and habitat opportunities for several species of threatened microbats and birds, including migratory shorebirds. Saltmarshes increased in extent relative to mangrove in Australia in both tide- and wave-dominated geomorphic settings through the latter Holocene, although historic trends have seen a reversal of this trend. Australian saltmarshes have some capacity to maintain elevation with respect to rising sea level, although in south-eastern Australia, the encroachment of mangrove and, in Tasmania, conversion of shrubland to herbfield in the past half-century are consistent with changes in relative sea level. Modelling of the impacts of projected sea-level rise, incorporating sedimentation and other surface-elevation drivers, suggests that the survival of saltmarsh in developed estuaries will depend on the flexible management of hard structures and other impediments to wetland retreat.
38
Hillyard, Karl A., Benjamin B. Smith, Anthony J. Conallin, and Bronwyn M. Gillanders. "Optimising exclusion screens to control exotic carp in an Australian lowland river." Marine and Freshwater Research 61, no. 4 (2010): 418. http://dx.doi.org/10.1071/mf09017.
Full textAbstract:
Carp exclusion screens (CES) are used to restrict adult common carp from entering wetlands, thereby minimising their ecological impacts and spawning and recruitment potential, but there is marked variation in current CES design and management. We quantified current CES designs, dimensions and locations within the Murray–Darling Basin, Australia. Directional fyke nets at inlets of six permanently inundated wetlands were used to identify fish using wetlands and therefore potentially vulnerable to CES. Morphometric data from captured fish were then used to design CES that excluded sexually mature carp. The ability of optimised and existing CES designs to exclude large-bodied fishes that used wetlands was then assessed. Fifty-four CES with eight mesh designs and varied dimensions were identified. We recorded 18 species comprising 212 927 fish in the wetland inlets. Two optimised meshes to exclude sexually mature carp were developed: a 44-mm square grid mesh and a ‘jail bar’ mesh with 31.4-mm gaps. Modelling revealed that up to 92% of carp could be excluded by either optimised mesh design, although few young-of-year carp were caught. Optimised and existing CES designs would also exclude 2–65% of large-bodied native fishes. Optimised CES may allow localised carp control without restricting passage of some key native fishes.
39
Casanova, Michelle T., and I. Joan Powling. "What makes a swamp swampy? Water regime and the botany of endangered wetlands in western Victoria." Australian Journal of Botany 62, no. 6 (2014): 469. http://dx.doi.org/10.1071/bt14119.
Full textAbstract:
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.
40
White, Laura, Claudia Catterall, and Kathryn Taffs. "The habitat and management of hairy jointgrass (Arthraxon hispidus, Poaceae) on the north coast of New South Wales, Australia." Pacific Conservation Biology 26, no. 1 (2020): 45. http://dx.doi.org/10.1071/pc19017.
Full textAbstract:
Ecological information about threatened species is required to guide strategic management approaches for effective biodiversity conservation in Australia. Arthraxon hispidus (hairy jointgrass) is a listed threatened species in New South Wales (NSW), but there is limited information on its habitat preferences and native vegetation associations, as well as the impact of historical and ongoing anthropogenic disturbance on its distribution and abundance. In the present study, populations of A. hispidus on the north coast of NSW were surveyed to investigate the habitat characteristics associated with various occurrences of the species. Its preferred habitat was found to be dense ground-cover formations in high-moisture, low-canopy conditions. Cover was highest in moisture-associated assemblages in and around wetlands, drainage lines and groundwater seepages, often in association with native grasses, sedges and herbs. These findings suggest that naturally open freshwater wetland communities comprise the most plausible native habitat niches for A. hispidus populations on the north coast of NSW. A. hispidus also occurs widely among introduced pastures and weeds in previously forested areas, demonstrating the species’ potential to exploit derived habitat. Results indicate that, although ongoing disturbance continues to promote A. hispidus in these exotic-dominated landscapes where historical clearing has created potential habitat opportunities, anthropogenic disturbance (slashing or cattle grazing) is not necessary to sustain A. hispidus within native-dominated wetland communities. Findings suggest more scope for integrated management of A. hispidus within broader native vegetation conservation strategies rather than a single species approach.
41
Hendrich, Lars, and Michael Balke. "New records of the diving beetle Rhantus simulans Régimbart, 1908 in south-western Australia (Coleoptera, Dytiscidae, Colymbetinae)." Check List 17, no. 2 (April 9, 2021): 643–48. http://dx.doi.org/10.15560/17.2.643.
Full textAbstract:
New distributional records of the rarely collected diving beetle Rhantus simulans Régimbart, 1908, an endemic species of south-western Australia, are presented. We also summarize what is known about its habitat. The occurrence of R. simulans indicates a high conservation value of the sampled wetland. For easier identification, we provide photographs of the habitus and male genitalia of R. simulans and R. suturalis (Macleay, 1825). Rhantus simulans is now recorded from 17 localities along the coast of south-western Australia. Furthermore, data on the location of other 31 diving beetle species are provided.
42
Ferdinands, Keith, Kerry Beggs, and Peter Whitehead. "Biodiversity and invasive grass species: multiple-use or monoculture?" Wildlife Research 32, no. 5 (2005): 447. http://dx.doi.org/10.1071/wr04036.
Full textAbstract:
Invasive plants are recognised as a major threat to biodiversity conservation worldwide. Despite this recognition, our understanding of the mechanisms controlling the invasion process and its impact on flora and fauna is often poor. We examined the impact of an invasive aquatic grass species, para grass (Urochloa mutica), on seasonally inundated wetlands in tropical northern Australia. Flora and avifauna were surveyed at sites invaded by para grass and in native vegetation. Spatial information systems were used to design surveys and determine environmental correlates of para grass distribution and so predict the potential future spread of para grass and infer impacts in the absence of control. Where para grass was present the median number of plant taxa was ~75% lower. Few birds showed preference for habitats invaded by para grass, and most birds were associated with areas of native vegetation or other habitats with little or no para grass. The study identified several wetland habitats that are at greater risk of invasion, based on the apparent habitat preferences of para grass. The degradation or loss of some of these ‘at-risk’ habitats, including Oryza meriodionalis grasslands that play an integral role in the wetland food chain, has important ramifications for the levels of biodiversity supported by the wetlands.
43
Boon, PI, P. Virtue, and PD Nichols. "Microbial consortia in wetland sediments: a biomarker analysis of the effect of hydrological regime, vegetation and season on benthic microbes." Marine and Freshwater Research 47, no. 1 (1996): 27. http://dx.doi.org/10.1071/mf9960027.
Full textAbstract:
Microbial consortia in the sediments from a permanent wetland near Albury-Wodonga in north-eastern Victoria, Australia (Ryans 1 Billabong), and an ephemeral wetland near Shepparton in central Victoria (Raftery's Swamp) were quantified by analyses of phospholipid fatty acid (PLFA), polar lipid ether lipid (PLEL), sterol and alcohol profiles. Prokaryotic organisms dominated the benthic assemblages in both wetlands. Total prokaryotic abundance (i.e. eubacteria plus archaea) was estimated to be (7-17) × 109 cells g-1 sediment (dry weight). Methanogenic archaea were estimated to number (1-5.4) × 109 cells g-1 and to account for 11-36% of the total benthic prokaryotes; these values are apparently among the highest recorded for temperate lake or river environments. PLFAs indicative of specific metabolic groups (e.g. sulfate-reducing bacteria (SRB), methanotrophic bacteria, etc.) were also detected. The PLFA profiles indicated that Type I methanotrophs (abundant in C16 PLFAs) were more abundant than the Type II group, which contain C18 PLFAs. Acetate-utilizing SRB were more abundant than were lactate-utilizing SRB, but neither group was dominant. Ergosterol was not detected, which suggested that fungi were not a significant component of the benthic microbial consortia in spite of both wetlands having abundant inputs from aquatic and fringing vascular plants. Other biomarkers, such as sterols, long-chain alcohols, triterpenoids and phytol, demonstrated inputs from these higher plants. PLFA, PLEL and sterol profiles indicated that benthic microbial consortia were affected by hydrological regime, the presence of aquatic vegetation, and season. Information from this preliminary study may assist in the making of informed management decisions on environmental water allocations for natural ecosystems.
44
CROWNS, J. E., J. A. Davis, F. CHEAL, L. G. Schmidt, R. S. ROSICH, and S. J. Bradley. "Multivariate pattern analysis of wetland invertebrate communities and environmental variables in Western Australia." Austral Ecology 17, no. 3 (September 1992): 275–88. http://dx.doi.org/10.1111/j.1442-9993.1992.tb00809.x.
Full text
45
Kurucz, N., S. Jacups, and J. M. Carter. "DeterminingCulex annulirostrislarval densities and control efforts across a coastal wetland, Northern Territory, Australia." Journal of Vector Ecology 41, no. 2 (November 17, 2016): 271–78. http://dx.doi.org/10.1111/jvec.12222.
Full text
46
Speldewinde, Peter C., Paul Close, Melissa Weybury, and Sarah Comer. "Habitat preference of the Australian water rat (Hydromys chrysogaster) in a coastal wetland and stream, Two Peoples Bay, south-western Australia." Australian Mammalogy 35, no. 2 (2013): 188. http://dx.doi.org/10.1071/am12001.
Full textAbstract:
This study provides a preliminary investigation of the home range and habitat selection of the Australian water rat (Hydromys chrysogaster) in Two Peoples Bay Nature Reserve near Albany, Western Australia. Six individuals were captured (trap success 1.9%) from 810 trap-nights. This low number suggests that the water rat population in Two Peoples Bay Nature Reserve is much smaller than anecdotal evidence would suggest. Home-range size (neighbour-linkage method) averaged 18.9 ha (±11.6). Individuals preferentially utilised wetland habitats characterised by dense, low-lying vegetation (0–30 cm from ground), low-density canopy cover and shallow, narrow water bodies.
47
Kobayashi, Tsuyoshi, Timothy J. Ralph, Pranay Sharma, and Simon M. Mitrovic. "Influence of historical inundation frequency on soil microbes (Cyanobacteria, Proteobacteria, Actinobacteria) in semi-arid floodplain wetlands." Marine and Freshwater Research 71, no. 5 (2020): 617. http://dx.doi.org/10.1071/mf18468.
Full textAbstract:
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.
48
Nielsen, Daryl L., Margaret A. Brock, Matthew Vogel, and Rochelle Petrie. "From fresh to saline: a comparison of zooplankton and plant communities developing under a gradient of salinity with communities developing under constant salinity levels." Marine and Freshwater Research 59, no. 7 (2008): 549. http://dx.doi.org/10.1071/mf07166.
Full textAbstract:
In Australia, many freshwater wetlands are becoming saline. Knowing which elements of a biotic community will persist as wetlands turn saline is relevant to their future management. We simulated gradual and sudden increases in salinity in outdoor mesocosms to test the hypotheses that: (1) aquatic plant and zooplankton communities exposed to a gradient of increasing salinity over time would initially resemble freshwater communities, but as the salinity increased they would resemble communities found in more saline systems; and (2) that a gradual change in salinity over 6 months influences zooplankton and plant communities in the same way as a sudden salinity change. Below 1000 mg L–1, as salinity increased gradually, communities rich in species and numbers of individuals resembled freshwater communities. However, as the salinity exceeded 1000 mg L–1, taxa were progressively lost and communities became less diverse. When salinities exceeded 3000 mg L–1 the diversity decreased rapidly and few taxa remained at 5000 mg L–1. Both sudden and gradual increases in salinity induced similar decreases in diversity. We predict that as natural wetlands become more saline, few freshwater biota will survive once the salinity exceeds 5000 mg L–1. In the long term, such salinised wetlands would need to be recolonised by salt-tolerant taxa for a functional wetland to persist.
49
McIntosh, Rebecca R., Romke Kats, Mathew Berg, Jan Komdeur, and Mark A. Elgar. "Breeding ecology and bias in offspring sex ratio in little grassbirds (Megalurus gramineus)." Australian Journal of Zoology 51, no. 5 (2003): 505. http://dx.doi.org/10.1071/zo03002.
Full textAbstract:
Little grassbirds (Megalurus gramineus) are small, sexually monomorphic passerines that live in reed beds, lignum swamps and salt marshes in southern Australia. The breeding biology and patterns of sex allocation of the little grassbird were investigated over a single breeding season. Our observations of this species in the Edithvale Wetland Reserve revealed a highly male-biased population sex ratio, with some breeding territories containing several additional males. Nevertheless, there was little compelling evidence that little grassbirds breed cooperatively. The growth rates of male and female nestlings were similar and, as predicted by theory, there was no overall primary sex ratio bias. However, the primary sex ratio was female-biased early in the breeding season and became increasingly male-biased later in the breeding season.
50
Clark, R. L., and J. C. Guppy Csiro. "A Transition from Mangrove Forest to Freshwater Wetland in the Monsoon Tropics of Australia." Journal of Biogeography 15, no. 4 (July 1988): 665. http://dx.doi.org/10.2307/2845444.
Full text