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Tropical forest degradation emits carbon at a rate of ~0.5 Pg x [y.sup.-1], reduces biodiversity, and facilitates forest clearance. Understanding degradation drivers and patterns is therefore crucial to managing forests to mitigate climate change and reduce biodiversity loss. Putative patterns of degradation affecting forest stocks, carbon, and biodiversity have variously been described previously, but these have not been quantitatively assessed together or tested systematically. Economic theory predicts a systematic allocation of land to its highest use value in response to distance from centers of demand. We tested this theory to see if forest exploitation would expand through time and space as concentric waves, with each wave targeting lower value products. We used forest data along a transect from 10 to 220 km from Dares Salaam (DES), Tanzania, collected at two points in time (1991 and 2005). Our predictions were confirmed: high-value logging expanded 9 km x [y.sup.-1], and an inner wave of lower value charcoal production 2 km x [y.sup.-1]. This resource utilization is shown to reduce the public goods of carbon storage and species richness, which significantly increased with each kilometer from DES [carbon, 0.2 Mg x [ha.sup.-1]; 0.1 species per sample area (0.4 ha)]. Our study suggests that tropical forest degradation can be modeled and predicted, with its attendant loss of some public goods. In sub-Saharan Africa, an area experiencing the highest rate of urban migration worldwide, coupled with a high dependence on forest-based resources, predicting the spatiotemporal patterns of degradation can inform policies designed to extract resources without unsustainably reducing carbon storage and biodiversity. biodiversity conservation | carbon emissions | reducing emissions from deforestation and forest degradation | sustainability | tropical forest degradation doi/ 10.1073/pnas.0914471107

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2010.02.004 Byline: Jessica Wiegand, Dave Raffaelli, James C.R. Smart, Piran C.L. White Abstract: The Ecosystem Approach to environmental management, with its explicit acknowledgment of the environmental, social and economic elements within ecological systems, is becoming increasingly adopted by managers and policy makers. However, there are few specific prescriptions as to exactly how these different elements should be integrated, or examples where historical changes have been tracked. Here, we assess the potential benefits and challenges of applying an Ecosystem Approach to management using one particular method, the Holistic Ecosystem Health Indicator (HEHI), which integrates data from the ecological, social and interactive dimensions into a single composite index of ecosystem 'health'. We apply it to one of the best-documented catchments in the UK, the Ythan Estuary in Aberdeenshire, Scotland, based on a 50-year time series of data. The evaluation of ecosystem health over time is lacking in previous applications of HEHI, yet is crucial for the assessment of the utility of this approach to ecosystem management. The application of HEHI yielded different insights to those revealed from the traditional application of biophysical approaches for managing the Ythan. Overall, ecological health declined through the 50-year period, although it increased marginally in the last decade, while social and interactive dimensions followed the opposite trend. HEHI indicated a steady increase in ecosystem health overall except for the last decade, when it declined marginally. Our evaluation of the application of ecosystem health for the Ythan revealed major data gaps. For the approach to be used more widely, issues of data availability and the temporal and geographical mismatch between ecological and social research boundaries need to be overcome. Author Affiliation: Environment Department, University of York, York YO10 5DD, UK Article History: Received 19 June 2009; Revised 11 January 2010; Accepted 7 February 2010

The results of a questionnaire study conducted in England and Wales is presented, to quantify the use, effectiveness and acceptability of the different methods currently used to manage wild mammals and future changes in management following a possible ban on hunting with dogs. It is said that a ban on hunting with dogs would make no difference to the management of the wild mammals, except hares, since the most effective way is shooting by day.

Managing receiving-water quality, ecosystem health and ecosystem service delivery is challenging in regions where extreme rainfall and runoff events occur episodically, confounding and often intensifying land-degradation impacts. We synthesize the approaches used in river, reservoir and coastal water management in the event-driven subtropics of Australia, and the scientific research underpinning them. Land-use change has placed the receiving waters of Moreton Bay, an internationally-significant coastal wetland, at risk of ecological degradation through increased nutrient and sediment loads. The event-driven climate exacerbates this issue, as the waterways and ultimately Moreton Bay receive large inputs of nutrients and sediment during events, well above those received throughout stable climatic periods. Research on the water quality and ecology of the region's rivers and coastal waters has underpinned the development of a world-renowned monitoring program and, in combination with catchment-source tracing methods and modeling, has revealed the key mechanisms and management strategies by which receiving-water quality, ecosystem health and ecosystem services can be maintained andimproved. These approaches provide a useful framework for management of water bodies in other regions driven by episodic events, or where novel stressors are involved (e.g., climate change, urbanization), to support sustained ecosystem service delivery and restoration of aquatic ecosystems. [ABSTRACT FROM AUTHOR]

1. The need to assess population size and change is central to any population monitoring programme. A range of monitoring techniques is available for deer, but few studies have addressed the performance of these techniques in terms of their accuracy and their power to detect population changes reliably. This study compares the performance of three commonly used techniques to monitor woodland deer populations in terms of their accuracy, precision and statistical power using field data and simulation modelling. 2. Faecal Standing Crop (FSC) was found to provide the most accurate estimates at all deer densities studied, but was outperformed by distance sampling using thermal imaging in terms of precision and statistical power. Faecal Accumulation Rate (FAR) performed worst in terms of precision and statistical power, and was inferior in terms of accuracy to FSC. The accuracy of FAR and distance sampling using thermal imaging was similar. 3. Annual surveying is not the best use of resources, since 10% per annum increases or decreases in a population could not be detected by any of the techniques within a 3-year time period. Even with the best technique under the most favourable conditions of deer density simulated in this study, a population change could only be detected reliably once the population had increased by 33% or decreased by 27%. In the least favourable conditions, the respective figures were a 380% increase or extinction. 4. All the techniques studied are relatively poor at detecting population change, so their use in practical deer management needs to be treated with caution. The consequences of relying on similar techniques to detect population change for rare species could be severe. [ABSTRACT FROM AUTHOR]