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Abstract: Analysis of aerial photographs shows that gully erosion in three catchments in south-east Queensland, Australia, was initiated by post-European settlement. Analysis of historical rainfall and runoff showed that for two of the catchments, gully initiation occurred during wet decadal periods. Historical descriptions of the settlement of south-east Queensland and Moreton Bay detail significant changes in landuse and clearing of vegetation for grazing of domestic animals and urban development since 1842. Historical gully erosion rates varied from 14 to 1826m2 yr−1 and erosion rates are positively correlated with catchment area multiplied by slope. Analysis of gully erosion rates showed a linear increase in planemetric area over time. Together, these data show gully initiation in the three catchments is associated with post-European settlement land use practices and above average rainfall and runoff. Initiation of gullying across the region is similar to the previous studies in south-east Australia and highlights the sensitivity of the landscape to vegetation clearing and alternating periods of above average rainfall and drought. [Copyright &y& Elsevier]

Background/Aims: These studies investigated the role of apoptosis following ischaemia/reperfusion (I/R) injury to the liver and the effect of pretreatment with Cyclosporin A.Methods: Male Sprague–Dawley rats received 30 min of warm ischaemia followed by a period of reperfusion of 6 h. Rats were given olive oil or Cyclosporin A (30 mg/kg p.o.) the day before surgery. Neutrophil numbers were assessed in haematoxylin–eosin-stained sections of liver. In situ staining of sections using TdT-mediated dUTP-fluorescein nick-end labelling was carried out to determine the extent of apoptosis, followed by electron microscopy. Semi-quantitative polymerase chain reaction (PCR) analysis of the transcript for Fas antigen was performed.Results and Conclusions: High levels of apoptosis were observed in I/R injury, which were greatly ameliorated in Cyclosporin A-pretreated groups. PCR analysis indicated a reduction in the level of expression of Fas transcript in Cyclosporin A-treated rats. Histological analysis showed a significant increase in the number of neutrophils infiltrating I/R-injured tissue (62±10.69, n=16), which was markedly reduced by Cyclosporin A pretreatment (16±7, n=6, P<0.05). These results indicate a role of parenchymal apoptosis in the pathogenesis of I/R injury, which occurs in association with neutrophil infiltration, both of which can be significantly reduced by Cyclosporin A pretreatment. [Copyright &y& Elsevier]

Freshwater ecosystems are declining under climate change and land-use change. To maximize the return on investment in freshwater conservation with limited financial resources, managers must prioritize management actions that are most cost-effective. However, little is known about what these priorities may be under the combined effects of climate and land-cover change. We present a novel decision-making framework for prioritizing conservation resources to different management actions for the conservation of freshwater biodiversity. The approach is novel in that it has the ability to model interactions, rank management options for dealing with conservation threats from climate and land-cover change, and integrate empirical data with expert knowledge. We illustrate the approach using a case study in South East Queensland (SEQ), Australia under climate change, land-cover change and their combined effects. Our results show that the explicit inclusion of multiple threats and costs results in quite different priorities than when costs and interactions are ignored. When costs are not considered, stream and riparian restoration, as a single management strategy, provides the greatest overall protection of macroinvertebrate and fish richness in rural and urban areas of SEQ in response to climate change and/or urban growth. Whereas, when costs are considered, farm/land management with stream and riparian restoration are the most cost-effective strategies for macroinvertebrate and fish conservation. Our findings support riparian restoration as the most effective adaptation strategy to climate change and urban development, but because it is expensive it may often not be the most cost-efficient strategy. Our approach allows for these decisions to be evaluated explicitly. [ABSTRACT FROM AUTHOR]

It is a substantial challenge to quantify the benefits which ecosystems provide to water supply at scales large enough to support policy making. This study tested the hypothesis that vegetation could reduce riverbank erosion, and therefore contribute to reducing turbidity and the cost of water supply, during a large magnitude flood along a 62 km riparian corridor where land cover differed substantially from natural conditions. Several lines of evidence were used to establish the benefits that vegetation provided to reducing eleven riverbank erosion processes over 1688 observations. The data and analyses confirmed that vegetation significantly reduced the magnitude of the riverbank erosion process which was the largest contributor to total erosion volume. For this process, a 1% increase in canopy cover of trees higher than five metres reduced erosion magnitude by between 2 and 3%. Results also indicate that riverbank erosion was likely to be affected by direct changes to the riparian corridor which influenced longitudinal coarse sediment connectivity. When comparing the impact of these direct changes on a relative basis, sand and gravel extraction was likely to be the dominant contributor to changed erosion rates. The locations where erosion rates had substantially increased were of limited spatial extent and in general substantial change in river form had not occurred. This suggests that the trajectory of river condition and increasing turbidity are potentially reversible if the drivers of river degradation are addressed through an ecosystem restoration policy. Unlabelled Image • 1% increase in vegetation canopy cover reduced riverbank erosion by between 2 and 3% • Changes to longitudinal coarse sediment connectivity also affected riverbank erosion • Both drivers need to be addressed for effective ecosystem restoration [ABSTRACT FROM AUTHOR]