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Summary Large overbank flood events play an important role in maintaining large-scale ecological processes and connectivity along and across the floodplains and between the rivers and their floodplains in the southern Murray-Darling Basin. However, the regulation of rivers means that extensive overbank flooding can only occur in the rare circumstance of extreme flood events. Recent environmental water allocations have focussed on the largest floodplain blocks ('icon' sites) and a small set of specific values (e.g. colonial nesting waterbirds), as well as on trialling fine-scale manipulation of infrastructure (e.g. pumping) to water relatively small areas. There has been no comprehensive systematic assessment of the entire floodplain and its wider set of flood-dependent natural assets (such as ecosystems and species; herein referred to as 'natural values') to maximise the effectiveness of environmental water use and to catalogue values likely to be lost. This paper describes an assessment of some 220 000 ha found to support flood-dependent natural values in Victoria. We mapped the geographic distribution and estimated components of the flooding requirements (natural flooding frequency, and maximum period without flooding and minimum duration of each flooding event before significant deterioration) for each natural value. Using an example of one stretch of the River Murray, we show how the resultant spatial data can be used with floodplain inundation modelling to compare the outcomes of real or planned environmental watering events; potentially providing tools for management agencies to conserve a wider range of floodplain values than is currently the case. That is, water managers and the public can see what ecosystems and threatened species are intended to be maintained by environmental watering and what values are intended to be abandoned across the whole floodplain, rather than just seeing the small subset of values and 'icon' sites that are intended to be maintained. Examples are provided to illustrate how information about the location, water requirements and extent covered by potential floods for specific values can be used to build adaptive watering strategies for areas as large as the whole floodplain. [ABSTRACT FROM AUTHOR]

Australia's rivers are among the most variable in the world and this has been a major challenge in catchments such as the Murray-Darling Basin where management has focused on increasing agricultural production while reducing risks from fluctuating water availability. Pressure for development and over-optimistic assessments of available water have resulted in over-allocation and increasing ecological decline, which has been severely exacerbated by record-breaking drought. In recent years, governments have agreed to radical policies such as the National Water Initiative 2004 and allocated substantial funds in response. Implementation is in gridlock, however, as the socio-economic implications have become clearer. Most debate is focused on the draft Murray-Darling Basin Plan due for release in mid-2010 before finalization in 2011. It will be the first Basin-wide plan and is intended to deal with inequities across borders and risks such as climate change and drought. Climate change scenarios for 2030 foresee a range of potential surface water availability outcomes, ranging from a 7% increase to a 37% decrease, yet greater water scarcity is being experienced in the current (2002+) drought with inflows reduced by 70% or more in extreme years. Contradictory policies are hindering the more open adaptation required to manage a drier future. [ABSTRACT FROM AUTHOR]

The Woolshed Creek fossil site near the Royal Military College, Duntroon, Canberra, contains brachiopods Atrypa duntroonensis (early Homerian, early Silurian, ca 430.5 Ma) within a mudstone of the Canberra Formation. Their discovery in 1844 by the Reverend William B. Clarke ("the Father of Australian Geology"), and subsequent comparison with other fossil collections from around the world, contributed significantly to the nineteenth century debate about the oldest rocks in Australia. The fossil site is now on the ACT Government Heritage List and recent site improvements make it readily accessible via a pathway from the sports grounds of the Royal Military College. [ABSTRACT FROM AUTHOR]

Prior to installation of a fishway at a road crossing in 2001, a remnant population of endangered Macquarie perch (Macquaria australasica) was confined to a 6-km section of the Cotter River, Australian Capital Territory. The purpose of the fishway was to provide passage past a barrier and to increase the extent of spawning grounds for M. australasica to an additional 22 km of river. The aim of the current study was to quantify the extent of nursery grounds of M. australasica in the Cotter River catchment by developing and applying a rapid, non-destructive technique for surveying juvenile M. australasica. From October to January in 2006-07 and 2007-08, pools were surveyed by snorkelling in the lower Cotter River to detect juvenile and larval M. australasica. The 9-km study reach consisted of the four pools immediately upstream of Cotter Reservoir, seven pools further upstream but still downstream of the rockramp fishway and 14 pools upstream of the fishway. In 2006-07, juvenile M. australasica were detected at 22 of 25 pools, including 13 of 14 pools upstream of the fishway. In spring/summer 2007-08, low visibility conditions frequently occurred throughout the river preventing survey on several occasions. However, recruitment of M. australasica was again detected upstream of the fishway. The increased extent of the nursery grounds of this M. australasica population has proven to be timely as an enlargement of the Cotter Reservoir, due for completion in 2012, will inundate more than 90% of prefishway nursery grounds in the Cotter River. Our study has demonstrated the benefit of installing a fishway in expanding the nursery grounds and the number of recruits of a remnant population of the endangered M. australasica. We also demonstrate the benefits of employing a visual survey technique to quantify the extent of the riverine nursery grounds of a fish population. Snorkel based surveys for larvae and juveniles quantified the upstream expansion in nursery grounds of the endangered Macquarie perch Macquaria australasica. The successful expansion has arisen from installation of a fishway on the Cotter River, Australian Capital Territory. [ABSTRACT FROM AUTHOR]

The article discusses about the water trade and management in Murray-Darling Basin in Canberra, Australian Capital Territory, and its role as a vital source of water in Australia. It also focuses on ways for the river to meet and sustain the country's needs as well as the negotiations and arrangements regarding rights to Murray River. The Murray-Darling Basin Agreement by the Council of Australian Government (COAG), the participation of indigenous groups in water trade and ways to control water pollution problem was also tackled.

Discusses the efforts to restore the Snowy River in Australia. Improvements imposed in the Murray-Darling River system; Status of the efficiency of the country's water system; Catchment management of the river.

Inland recreational swimming sites provide significant social value globally. This study focused on public recreational swimming sites across the Murrumbidgee River and its tributaries in the Australian Capital Territory (ACT) throughout the swimming season (September-April) from 2009 to 2020 to determine whether high intestinal enterococci concentrations could be predicted with flow exceedance and routinely monitored physical and chemical parameters of water quality. Enterococci concentrations were positively correlated with the turbidity associated with high-flow conditions. The predictive accuracy of high enterococci levels during high-flow conditions was good (mean percentage correctly classified, 60%). The prediction of high enterococci levels at low flows was significantly less reliable (mean percentage correctly classified, 12-15%). As the ACT is expected to experience decreases in rainfall overall but increases in extreme rainfall events due to climate change, understanding the drivers of elevated intestinal enterococci under extreme flow conditions remains important from a public health perspective. [ABSTRACT FROM AUTHOR]

Satellite imagery is the only feasible approach to annual monitoring and reporting on land cover change. Unfortunately, conventional pixel-based classification methods based on spectral response only (e.g., using random forests algorithms) have shown a lack of spatial and temporal stability due, for instance, to variability between individual pixels and changes in vegetation condition, respectively. Machine learning methods that consider spatial patterns in addition to reflectance can address some of these issues. In this study, a convolutional neural network (CNN) model, U-Net, was trained for a 500 km × 500 km region in southeast Australia using annual Landsat geomedian data for the relatively dry and wet years of 2018 and 2020, respectively. The label data for model training was an eight-class classification inferred from a static land-use map, enhanced using forest-extent mapping. Here, we wished to analyse the benefits of CNN-based land cover mapping and reporting over 34 years (1987–2020). We used the trained model to generate annual land cover maps for a 100 km × 100 km tile near the Australian Capital Territory. We developed innovative diagnostic methods to assess spatial and temporal stability, analysed how the CNN method differs from pixel-based mapping and compared it with two reference land cover products available for some years. Our U-Net CNN results showed better spatial and temporal stability with, respectively, overall accuracy of 89% verses 82% for reference pixel-based mapping, and 76% of pixels unchanged over 33 years. This gave a clearer insight into where and when land cover change occurred compared to reference mapping, where only 30% of pixels were conserved. Remaining issues include edge effects associated with the CNN method and a limited ability to distinguish some land cover types (e.g., broadacre crops vs. pasture). We conclude that the CNN model was better for understanding broad-scale land cover change, use in environmental accounting and natural resource management, whereas pixel-based approaches sometimes more accurately represented small-scale changes in land cover. [ABSTRACT FROM AUTHOR]

Populations of macropods are higher than estimated pre‐European densities in many parts of Australia. To achieve appropriate densities of macropods in the Australian Capital Territory's nature reserves, multi‐tenure kangaroo management units are used to tailor management of kangaroos and total grazing pressure to achieve conservation objectives. An adaptive management framework is recommended that monitors the state of the ground‐layer vegetation and alters the cull accordingly. This case study may provide insights for kangaroo management in other temperate areas of Australia. [ABSTRACT FROM AUTHOR]

The genus Tasmanitachoides Erwin, a genus of very small carabid beetle endemic to Australia, is reviewed. Although uncommon in collections, they can be abundant and diverse on banks of fine gravel or coarse sand next to bodies of fresh water; samples from southeastern Australia suggest numerous undescribed species. An initial phylogenetic hypothesis for the genus is presented, including 19 of the 32 known species. The inferred phylogeny, based upon one mitochondrial and four nuclear genes, shows the kingi group to be sister to remaining Tasmanitachoides, with the wattsensis group and T. lutus (Darlington) also being phylogenetically isolated. Two new species are described: T. baehri sp. nov., from the Australian Capital Territory, is a member of the kingi group; T. erwini sp. nov., from Tasmania, is a member of the wattsensis group. Identification tools for described and some undescribed species are presented, including photographs of all known species. [ABSTRACT FROM AUTHOR]

The Murray–Darling Basin covers parts of four States of Australia and the whole of the Australian Capital Territory. As at 2002, its water management was well regarded internationally. Basin flows are low and variable. The most reliable streams show variations of about 12:1 between maximum and minimum annual natural flows. The longest tributary, the Darling, has a ratio of infinity. It was recognized in the 1980s that extractions from the system, largely for irrigation, had to be constrained. That led to the introduction of the "Murray‐Darling Basin Cap" which limited extractions and recognized the probability of average inflows declining, which was already being predicted by climate change modelling. The "millennium drought" of 2000–2009 was very severe and led to fears that the drop in inflows was happening faster than modelling was predicting. In 2007, the National Government, on the eve of an election, declared that the Basin had been mismanaged for a century by the States and legislated to transfer management powers from the States to the Commonwealth. That transfer has been pursued since then by National Governments of both major parties. Government claims to have "taken the politics out of Basin management and returned to the science." The evidence is that the exact opposite has occurred. The paper traces the history of water management in the Basin. © 2020 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary 1. The formation of sulfidic sediments in response to factors such as secondary salinisation and fertiliser usage is an emerging concern for the management of many freshwater wetlands. However, fundamental knowledge regarding the influence of sulfidic sediments on the aquatic biota is still lacking. 2. This study investigated the potential for biota to recolonise wetlands affected by sulfidic sediments, by assessing zooplankton hatching and aquatic plant germination following inundation with freshwater. Sediment samples were collected from 16 wetlands in the southern Murray-Darling Basin, Australia, that ranged in condition from non-impacted to possessing a known history of sulfidic sediments and/or acidification. 3. Principal Components Analysis indicated that the wetlands separated out into five different groups based on their sediment chemistry: non-impacted, sulfidic, sulfidic and highly saline (sediment EC 46 800-209 000 μS cm−1), sulfidic and potentially acidic (sediment pH 5.81-6.45 and ANC 0.07-0.31% CaCO3), and sulfidic and acidic (sediment pH 4.37 and ANC 0.00% CaCO3). 4. A viable dormant propagule bank was present in all wetlands, but the taxon richness of zooplankton and aquatic plants was significantly lower in wetlands affected by sulfidic sediments compared with those that were non-affected. 5. This suggests that zooplankton and aquatic plants will be capable of recolonising wetlands that have accumulated sulfidic sediments via their propagule banks if the appropriate remediation measures are undertaken, although the communities developing are likely to be less diverse compared with those in non-affected wetlands. [ABSTRACT FROM AUTHOR]

The article presents abstracts on medical topics which include quality care in resource poor situations, emergency medicine in the South Pacific, and the introduction of a primary trauma care (PTC) course in Myanmar.

The article presents a study on the role of groundwater discharge from Riverine Plains of the Murray-Darling Basin to the salt mobilization to the Murray River in Australia. It discusses the methodologies applied in the study which includes the classification and regression trees, conceptual modeling, and artificial neural networks that provides analyses from monthly data dated from July 1975 to December 2004. It focuses on greater significance of rainfall in salt loads compared to irrigation water.

Anthropogenic warming of the global climate system is beyond doubt. Impacts from a changing climate are already occurring and the latest scientific research suggests that some aspects are locked in for centuries to come. Climate change therefore poses one of the greatest challenges to Australia's environment and water resources. Historical experience and past trends may no longer be a reliable predictor of the future. This article provides a brief overview of the latest scientific research and thinking on the climate change challenge. Observed changes and projections for temperature, rainfall, extreme events and ocean acidification are presented in an Australian context. The impacts of a range of climate change drivers are summarised, expanding upon the well-accepted general warming and drying trend for southern and eastern Australia. Current thinking regarding 'dangerous' climate change is that we are tracking on the higher end scale or above of the worst case scenario predictions reported by the IPCC Fourth Assessment Report (IPCC AR4) released in 2007. The implications for Australia's water resources, and in particular the Murray-Darling Basin, are significant. There appears to be a brief window of opportunity to act and adapt to enhance resilience to climate change; however, this requires an urgent and sustained commitment, and investment in Australia's environmental assets. [ABSTRACT FROM AUTHOR]

Australia - Limits to Government Water Buy-Backs for Environmental Flows in the Murray-Darling Basin (Part 1) (Vinoli Thampapillai) 247 Professor HAN Depei, 1911-2009 - In memoriam (Qin Tianbao) 265 Italy - Access to Courts - NGOs are Alarmed - (Deirdre Exell Pirro) 266 USA - Richard L. Ottinger Receives 2009 US EPA Award 268 [ABSTRACT FROM AUTHOR]

Droughts, changing weather patterns due to climate change, unsustainable state and federal government policies and parochial self interest has brought the major irrigated agricultural region of Australia, the Murray-Darling Basin close to collapse. The present state of the Basin together with the predictions of computer modelling of future climate changes over the next few decades is discussed in relation to the existing attitudes of vested interests at all levels and the various policies now being undertaken by governments in an attempt to address the major problems. [ABSTRACT FROM AUTHOR]

With limited evidence linking Australia's Murray-Darling Basin fish species and flooding, this study assessed annual variation in abundance and recruitment levels of a small-bodied, threatened floodplain species, the Southern Pygmy Perch ( Nannoperca australis), in floodplain habitats (creeks, lakes and wetlands) in the Barmah-Millewa Forest, Murray River, Australia. Spring and summer sampling over a 5-year period encompassed large hydrological variation, including 1 year of extended floodplain inundation which was largely driven by an environmental water release, and 2 years of severe regional drought. Recruitment and dispersal of Southern Pygmy Perch significantly increased during the floodplain inundation event compared with the other examined years. This study provides valuable support for an environmental water allocation benefiting a native species, and explores the link between flooding and its advantages to native fish. This suggests that the reduced flooding frequency and magnitude as a result of river regulation may well be a major contributing factor in the species’ decline in the Murray-Darling Basin. [ABSTRACT FROM AUTHOR]

The Standard Precipitation Index (SPI) is employed to track drought and assess the impact of rainfall on shallow groundwater levels in three selected irrigation areas of the Murray-Darling Basin in Australia. The continuous SPI method can provide better means of quantifying rainfall variability and correlating it with changes of shallow watertable levels since it is based on continuous statistical functions comparing rainfall variability over the entire rainfall record. Drought analysis in the Australian irrigation areas using SPI indicates that the recent 2000–2006 drought is not the worst drought that has occurred in the recorded history, however if the current low rainfall pattern continues, it would be one of the most prolonged drought. The shallow groundwater fluctuations in the Murrumbidgee Irrigation Area show a very strong correlation with winter rainfall variation. The shallow piezometric levels in the Coleambally Irrigation Area show a weaker degree of correlation with the SPI due to local and regional groundwater dynamics and changes in rice water use. The groundwater levels in the Murray Irrigation Area show least correlation with the SPI, which may be attributed to improved irrigation management practices and complex nature of the groundwater recharge and discharge processes in this area. The overall results however show that the SPI correlates well with fluctuations in shallow ground water table in irrigation areas, and can also capture major drought patterns in Australia. The correlation of SPI with groundwater levels can be adopted for environmental reporting and used as a method of relating climatic impacts on watertables. Differences in piezometric response between years with similar winter and yearly SPI values can be attributed to improvement in irrigators’ management practices. [ABSTRACT FROM AUTHOR]

Much concern about the negative environmental consequences of agricultural development in Australia, including salinisation, waterlogging and algal blooms, has focused on the problems of the Murray-Darling Basin. The aim of this article is to provide an overview of the environmental problems of the Murray-Darling Basin from an economic perspective, and a selective survey of the relevant economic literature, including theoretical analysis, modelling and contributions to the development of water policy. In attempting to understand the complex problems of the Murray-Darling Basin, an eclectic approach drawing on externality, sustainability and property rights perspectives seems most appropriate. [ABSTRACT FROM AUTHOR]

"Canberra is the only really modern city in the world. Not that that has been made obvious to the casual glance, but a structure can only be truly modern when the foundations are properly laid for that particular thing. . . . For this science . . . had died out and was no longer practiced." (Marion Mahony Griffin, 'Canberra, its Designer and its Plan', The Centennial Anniversary of the Founding of Australia, Magic of America, Federal Battle, p. 380.). [ABSTRACT FROM AUTHOR]

Water markets have featured prominently in the reallocation of water rights to restore freshwater ecosystem health. Incentive-based water rights acquisition and transactions have emerged as a market-oriented policy approach to reallocate water resources from existing uses to enhance the provision, regulation, and sustainability of freshwater ecosystem services. This paper develops a conceptual framework to examine factors enabling and constraining successful policy reform and implementation in market-based environmental water allocation. This analysis distills and extends the findings and lessons of a September 2007 workshop in Brisbane, Australia on environmental water transactions. Two case studies were selected in water stressed basins – the Columbia (U.S.) and Murray-Darling (Australia) Basins – where transactional approaches to environmental water allocation first emerged. The case studies draw upon practitioner perspectives and previous policy and economic analysis in two regions where shared political economic and physical conditions lend a strong analytical basis for comparison. A common set of policy and regulatory reforms has occurred in both cases – albeit in different forms and via distinct paths – to develop three enabling conditions: (1) establishment of rights to and limits on freshwater extraction and alteration; (2) recognition of the environment as a legitimate water use; and (3) authority to transfer existing water rights to an environmental purpose. However, these elements of policy reform are necessary but not sufficient for effective implementation; a second set of driving forces, barriers, and adaptations explains the ability to achieve larger scale ecological outcomes. These conditions include the physical, social and economic factors driving demand for environmental water allocation; administrative procedures, organizational development and institutional capacity to effect transfers; and adaptive mechanisms to overcome legal, cultural, economic, and environmental barriers. The case study analysis suggests that environmental water transactions can play an important role in establishing environmental water allocations, although water markets require ongoing institutional capacity and adaptive governance. The conceptual framework and empirical lessons generated through this cross-case comparison provide the basis for an expanded research agenda to evaluate the design and performance of market-oriented reforms as implementation experience accrues and new programs emerge in diverse ecological and political economic settings. [Copyright &y& Elsevier]