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Fred A. Otchere Marcello M. Veiga Jennifer J. Hinton Renato A. Farias Robert Hamaguchi 《Natural resources forum》2004,28(3):216-223
The legacy of mining activities has typically been land ‘returned to wildlife’, or, at some sites, degraded to such an extent that it is unsuitable for any alternate use. Progress towards sustainability is made when value is added in terms of the ecological, social and economic well‐being of the community. In keeping with the principles of sustainable development, the innovative use of flooded open pits and tailings impoundments as commercial, recreational or ornamental fish farms should be considered in some locations, as it could make a significant contribution to the social equity, economic vitality and environmental integrity of mining communities. This article highlights the growing significance of aquaculture and explores the benefits and barriers to transforming flooded pits and impoundments into aquaculture operations. Among other benefits, aquaculture may provide a much‐needed source of revenue, employment and, in some cases, food to communities impacted by mine closure. Further, aquaculture in a controlled closed environment may be more acceptable to critics of fish farming who are concerned about fish escapes and viral transmissions to wild populations. Despite the potential benefits, aquaculture in flooded pits and impoundments is not without its complications — it requires a site‐specific design approach that must consider issues ranging from metals uptake by fish, to the long‐term viability of the aquatic system as fish habitat, to the overall contribution of aquaculture to sustainability. 相似文献
266.
Michelle L. Soupir Saied Mostaghimi Amanda Masters Katherine A. Flahive David H. Vaughan Aida Mendez Phillip W. McClellan 《Journal of the American Water Resources Association》2004,40(1):53-66
ABSTRACT: Erosion from construction sites significantly affects water quality in receiving streams. A rainfall simulator was used to evaluate the effectiveness of different methods for controlling erosion from construction sites. Erosion control methods investigated included dry and liquid applications of polyacrylamide (PAM), hydroseed, and straw mulch. Fertilizer was also applied to each plot to examine the effectiveness of the methods in reducing nutrient losses in runoff. Runoff samples were analyzed for total suspended solids (TSS), nitrate, total Kjeldahl nitrogen (TKN), ammonium, total phosphorus (TP), and orthophosphate. Among all treatments investigated, straw mulch was the most effective treatment for controlling TSS and nutrient losses during short term and long term simulations. The low liquid PAM (half the recommended PAM) treatment resulted in the highest reduction in runoff, TSS bound nitrogen, and total nitrogen (TN) concentrations and loadings. The study results indicate that a high application rate (twice the recommended rate) of PAM could actually increase runoff and TSS losses. At a low application rate, both liquid and dry PAM were effective in reducing TSS and nutrient losses in runoff. However, application of the liquid form of PAM to construction sites is more practical and perhaps more economical than applying the PAM in the dry form. 相似文献
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Donna M. Cosgrove Gary S. Johnson 《Journal of the American Water Resources Association》2004,40(6):1469-1482
ABSTRACT: Increasing demands on western water are causing a mounting need for the conjunctive management of surface water and ground water resources. Under western water law, the senior water rights holder has priority over the junior water rights holder in times of water shortage. Water managers have been reluctant to conjunctively manage surface water and ground water resources because of the difficulty of quantification of the impacts to surface water resources from ground water stresses. Impacts from ground water use can take years to propagate through an aquifer system. Prediction of the degree of impact to surface water resources over time and the spatial distribution of impacts is very difficult. Response functions mathematically describe the relationship between a unit ground water stress applied at a specific location and stream depletion or aquifer water level change elsewhere in the system. Response functions can be used to help quantify the spatial and temporal impacts to surface water resources caused by ground water pumping. This paper describes the theory of response functions and presents an application of transient response functions in the Snake River Plain, Idaho. Transient response functions can be used to facilitate the conjunctive management of surface and ground water not only in the eastern Snake River Plain basin, but also in similar basins throughout the western United States. 相似文献
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广东省的地质灾害与防治对策 总被引:8,自引:0,他引:8
广东省地质灾害类型多,分布广,频率高,危害大.地震、滑坡、崩塌、地裂缝、地面塌陷、地面沉降和软土地基变形等地质灾害是影响当地经济发展和城乡建设的消极因素.地质灾害的时间分布具有波动性,过去35年来存在两个明显的高发期,分别是1985-1992年和1997年至今;其空间分布具有区域耦合性,地质构造复杂、自然环境恶劣的粤西、粤北低山丘陵区和人类活动剧烈、经济发达的沿海平原地区都是重灾区.地质灾害与自然条件、人类活动关系密切.它们的防治应以防为主,防治结合,将生态与工程措施相结合,并调整人类的经济行为,保持生态环境的平衡. 相似文献
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环境政策作用机制的分析框架 总被引:1,自引:0,他引:1
了解环境政策作用机制是环境政策有效调控的前提和核心,准确理解环境政策作用的背景、成因、过程、作用机制、效应动态、演变规律等;全面而深刻地环境政策副作用和变形的生成-演变规律,了解政策副作用形成机制、传导机制、积累发展机制、作用机制、研究政策变形对环境政策适应性和效率的影响才可能准确预测环境政策所引发的变化,这些变化对社会经济的影响,进而对环境政策的反馈影响和反馈作用,才可能准确有效地设计开发政策工具和调控机制,有铲地进行环境政策调控,提高环境政策的预见性、准确性、操作性和适应性。 相似文献