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321.
This paper presents a decision support system (DSS) for sustainable development and environmental protection of agricultural regions developed in the framework of the Interreg-Archimed project entitled WaterMap (development and utilization of vulnerability maps for the monitoring and management of groundwater resources in the ARCHIMED areas). Its aim is to optimize the production plan of an agricultural region taking in account the available resources, the environmental parameters, and the vulnerability map of the region. The DSS is based on an optimization multicriteria model. The spatial integration of vulnerability maps in the DSS enables regional authorities to design policies for optimal agricultural development and groundwater protection from the agricultural land uses. The DSS can further be used to simulate different scenarios and policies by the local stakeholders due to changes on different social, economic, and environmental parameters. In this way, they can achieve alternative production plans and agricultural land uses as well as to estimate economic, social, and environmental impacts of different policies. The DSS is computerized and supported by a set of relational databases. The corresponding software has been developed in a Microsoft Windows XP platform, using Microsoft Visual Basic, Microsoft Access, and the LINDO library. For demonstration reasons, the paper includes an application of the DSS in a region of Northern Greece.  相似文献   
322.
The Arctic is undergoing biological and environmental changes, and a coordinated effort to monitor is critical to detect these changes. The Circumpolar Biodiversity Monitoring Programme (CBMP) of the Arctic Council biodiversity working group, Conservation of Arctic Flora and Fauna (CAFF), has developed pan-Arctic biodiversity monitoring plans that aims to improve the ability to detect and report on long-term changes. Whilst introducing this special issue, this paper also presents the making of the terrestrial monitoring plan and discusses how the plan follows the steps required for an adaptive and ecosystem-based monitoring programme. In this article, we discuss how data on key findings can be used to inform circumpolar and global assessments, including the State of the Arctic Terrestrial Biodiversity Report, which will be the first terrestrial assessment made by the CBMP. Key findings, advice for future monitoring and lessons learned will be used in planning next steps of pan-Arctic coordinated monitoring.  相似文献   
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Ambio - This review provides a synopsis of the main findings of individual papers in the special issue Terrestrial Biodiversity in a Rapidly Changing Arctic. The special issue was developed to...  相似文献   
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ABSTRACT

Reductions in airborne sulfate concentration may cause inorganic fine particulate matter (PM25) to respond nonlinearly, as nitric acid gas may transfer to the aerosol phase. Where this occurs, reductions in sulfur dioxide (SO2) emissions will be much less effective than expected at reducing PM2.5. As a measure of the efficacy of reductions in sulfate concentration on PM , we define marginal PM2.5 as the local change in PM2.5 resulting from a small change in sulfate concentration. Using seasonal-average conditions and assuming thermodynamic equilibrium, we find that the conditions for PM2.5 to respond nonlinearly to sulfate reductions are common in the eastern United States in winter, occurring at half of the sites considered, and uncommon in summer, due primarily to the influence of temperature. Accounting for diurnal and intraseasonal variability, we find that seasonal-average conditions provide a reasonable indicator of the time-averaged PM2.5 response. These results indicate that reductions in sulfate concentration may be up to 50% less effective at reducing the annual-average PM2.5 than if the role of nitric acid is neglected. Further, large reductions in sulfate will also cause an increase in aerosol nitrate in many regions that are the most acidic.  相似文献   
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The expansion of sugarcane production in the Brazilian Cerrado has resulted in indirect land use change (ILUC), occurring when displaced land uses in one location are reallocated to another. Studies, however, usually identify ILUC at the regional or national level far from the original area of a displaced land use. This study examines the occurrence of ILUC due to sugarcane expansion for ethanol production at the farm level in the Brazilian Cerrado. It fills a gap in the literature by examining socioeconomic, policy and farm-level factors that influence ILUC at the farm level in the Brazilian Cerrado using face-to-face enumerated surveys. Results indicate that ILUC did occur at the farm (producer) scale and farmers who undertook ILUC intensified agricultural production on their farms. Results inform policymakers on how the intensification of agricultural practices may make it potentially difficult to keep protected lands out of production, reducing the environmental benefits from sugarcane-based biofuel production.  相似文献   
328.
Biochemical indices of white (WM) and red muscle (RM) aerobic and anaerobic metabolic capacity were measured in 14 species of benthic and benthopelagic chondrichthyans from a depth of ~90 to 2,200 m to evaluate the relationship between metabolic capacity and depth of occurrence, phylogeny, and locomotor mode. Maximal activities of the enzymes citrate synthase, malate dehydrogenase (MDH), lactate dehydrogenase (LDH), and pyruvate kinase (PK) were analyzed in muscle tissue at 10 °C. These were combined with previously published elasmobranch data in order to represent a comprehensive range of depths, phylogeny, and locomotor modes (i.e., benthic, benthopelagic, pelagic). Significant decreases in WM PK and LDH activities and a lack of significant trends in RM enzyme activities with increasing median depth of occurrence (MDO) indicate a depth-related reduction in both burst-locomotor and metabolic capacity. These trends are consistent with the “visual-interactions hypothesis.” Phylogeny and locomotor mode had little influence on enzyme activities compared to MDO, and the present study suggests similar activities in co-occurring demersal sharks and rays. Overall, the present study indicates low metabolic capacities in deep-sea chondrichthyans, which is important to consider when managing deep-sea fisheries.  相似文献   
329.
Reveals the synergy between microbial fuel cells and electrocoagulation. Demonstrates MFC-ECC shipboard wastewater treatment is advantageous. MFC-ECC integration enables energy neutral bilge water treatment. Ships generate large amounts of wastewater including oily bilge water, blackwater and greywater. Traditionally they are treated separately with high energy consumption. In this study we demonstrate the feasibility that these waste streams can be treated using an integrated electrocoagulation cell (ECC) and microbial fuel cell (MFC) process, which not only synergized the contaminants removal but also accomplished energy neutrality by directly powering EC with MFC electricity. Results showed that MFC stack powered ECC removed 93% of oily organics, which is comparable to the performance of an external DC voltage powered ECC. In the meantime, more than 80% of COD was removed from MFCs when fed with either acetate or municipal wastewater. Moreover, the ECC electrode area and distance showed notable effects on current generation and contaminants removal, and further studies should focus on operation optimization to enhance treatment efficiency.  相似文献   
330.
Conservation of biologically diverse regions has thus far been accomplished largely through the establishment and maintenance of protected areas. Climate change is expected to shift climate space of many species outside existing reserve boundaries. We used climate-envelope models to examine shifts in climate space of 11 species that are representative of the Mount Hamilton Project area (MHPA) (California, U.S.A.), which includes areas within Alameda, Santa Clara, San Joaquin, Stanislaus, Merced, and San Benito counties and is in the state's Central Coast ecoregion. We used Marxan site-selection software to determine the minimum area required as climate changes to achieve a baseline conservation goal equal to 80% of existing climate space for all species in the MHPA through 2050 and 2100. Additionally, we assessed the costs associated with use of existing conservation strategies (land acquisition and management actions such as species translocation, monitoring, and captive breeding) necessary to meet current species-conservation goals as climate changes. Meeting conservation goals as climate changes through 2050 required an additional 256,000 ha (332%) of protected area, primarily to the south and west of the MHPA. Through 2050 the total cost of land acquisition and management was estimated at US$1.67-1.79 billion, or 139-149% of the cost of achieving the same conservation goals with no climate change. To maintain 80% of climate space through 2100 required nearly 380,000 additional hectares that would cost $2.46-2.62 billion, or 209-219% of the cost of achieving the same conservation goals with no climate change. Furthermore, maintaining 80% of existing climate space within California for 27% of the focal species was not possible by 2100 because climate space for these species did not exist in the state. The high costs of conserving species as the climate changes-that we found in an assessment of one conservation project-highlights the need for tools that will aid in iterative goal setting given the uncertainty of the effects of climate change and adaptive management that includes new conservation strategies and consideration of the long-term economic costs of conservation.  相似文献   
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