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Constructed wetlands may compensate to some degree for the impact of the loss of natural wetlands on aquatic biodiversity. However, information is lacking on the relative value of artificial wetlands and comparable natural wetlands for freshwater turtles. I contrasted the population structure, diet and body growth of Australian eastern long-necked turtles (Chelodina longicollis) in artificial and natural ponds in farmland settings. Turtle populations in the artificial ponds had a more even distribution of body size, and a much larger proportion of young individuals, than those in the natural ponds, suggesting that the artificial ponds were important recruitment sites. Diet differed little between the two types of ponds, being greatly dominated by aquatic insects in both cases. However, body growth of juvenile turtles was on average more rapid in the artificial ponds, possibly because they were generally permanent, unlike the natural ponds. These findings suggest that artificial farm ponds are valuable habitats for C. longicollis, which may foster population recruitment that counters the effects of introduced nest predators and road mortality. [ABSTRACT FROM AUTHOR]

For several decades there has been recognition that water resource development alters river flow regimes and impacts ecosystem values. Determining strategies to protect or restore flow regimes to achieve ecological outcomes is a focus of water policy and legislation in many parts of the world. However, consideration of existing environmental flow assessment approaches for application in Queensland identified deficiencies precluding their adoption. Firstly, in managing flows and using ecosystem condition as an indicator of effectiveness, many approaches ignore the fact that river ecosystems are subjected to threatening processes other than flow regime alteration. Secondly, many focus on providing flows for responses without considering how often they are necessary to sustain ecological values in the long-term. Finally, few consider requirements at spatial-scales relevant to the desired outcomes, with frequent focus on individual places rather than the regions supporting sustainability. Consequently, we developed a risk-based ecohydrological approach that identifies ecosystem values linked to desired ecological outcomes, is sensitive to flow alteration and uses indicators of broader ecosystem requirements. Monitoring and research is undertaken to quantify flow-dependencies and ecological modelling is used to quantify flow-related ecological responses over an historical flow period. The relative risk from different flow management scenarios can be evaluated at relevant spatial-scales. This overcomes the deficiencies identified above and provides a robust and useful foundation upon which to build the information needed to support water planning decisions. Application of the risk assessment approach is illustrated here by two case studies. [ABSTRACT FROM AUTHOR]