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321.
The impounding of the Three Gorges Reservoir (TGR) at the Yangtze River caused large flooding of urban, industrial, and agricultural areas, and profound land use changes took place. Consequently, substantial amounts of organic and inorganic pollutants were released into the reservoir. Additionally, contaminants and nutrients are entering the reservoir by drift, drainage, and runoff from adjacent agricultural areas as well as from sewage of industry, aquacultures, and households. The main aim of the presented research project is a deeper understanding of the processes that determines the bioaccumulation and biomagnification of organic pollutants, i.e., mainly pesticides, in aquatic food webs under the newly developing conditions of the TGR. The project is part of the Yangtze-Hydro environmental program, financed by the German Ministry of Education and Science. In order to test combinations of environmental factors like nutrients and pollution, we use an integrated modeling approach to study the potential accumulation and biomagnification. We describe the integrative modeling approach and the consecutive adaption of the AQUATOX model, used as modeling framework for ecological risk assessment. As a starting point, pre-calibrated simulations were adapted to Yangtze-specific conditions (regionalization). Two exemplary food webs were developed by a thorough review of the pertinent literature. The first typical for the flowing conditions of the original Yangtze River and the Daning River near the city of Wushan, and the second for the stagnant reservoir characteristics of the aforementioned region that is marked by an intermediate between lake and large river communities of aquatic organisms. In close cooperation with German and Chinese partners of the Yangtze-Hydro Research Association, other site-specific parameters were estimated. The MINIBAT project contributed to the calibration of physicochemical and bathymetric parameters, and the TRANSMIC project delivered hydrodynamic models for water volume and flow velocity conditions. The research questions were firstly focused on the definition of scenarios that could depict representative situations regarding food webs, pollution, and flow conditions in the TGR. The food webs and the abiotic site conditions in the main study area near the city of Wushan that determine the environmental preconditions for the organisms were defined. In our conceptual approach, we used the pesticide propanil as a model substance.  相似文献   
322.
湿地生态系统具有净化污水的功能,因其具有高效低耗等优点,在污水处理方面极具开发应用前景,而基质作为湿地生态系统重要组成部分,已成为众多学者的研究热点。本文综合分析了湿地生态系统基质中重金属积累和酶活性的时空分布及影响因素的研究现状,并对相关研究提出了新的认识与展望,以期为湿地生态系统基质去除废水中重金属的深入研究和应用提供综合分析资料。  相似文献   
323.
Temporal and spatial vegetation structure has impact on biodiversity qualities. Yet, current schemes of biotope mapping do only to a limited extend incorporate these factors in the mapping. The purpose of this study is to evaluate the application of a modified biotope mapping scheme that includes temporal and spatial vegetation structure. A refined scheme was developed based on a biotope classification, and applied to a green structure system in Helsingborg city in southern Sweden. It includes four parameters of vegetation structure: continuity of forest cover, age of dominant trees, horizontal structure, and vertical structure. The major green structure sites were determined by interpretation of panchromatic aerial photographs assisted with a field survey. A set of biotope maps was constructed on the basis of each level of modified classification. An evaluation of the scheme included two aspects in particular: comparison of species richness between long-continuity and short-continuity forests based on identification of woodland continuity using ancient woodland indicators (AWI) species and related historical documents, and spatial distribution of animals in the green space in relation to vegetation structure. The results indicate that (1) the relationship between forest continuity: according to verification of historical documents, the richness of AWI species was higher in long-continuity forests; Simpson’s diversity was significantly different between long- and short-continuity forests; the total species richness and Shannon’s diversity were much higher in long-continuity forests shown a very significant difference. (2) The spatial vegetation structure and age of stands influence the richness and abundance of the avian fauna and rabbits, and distance to the nearest tree and shrub was a strong determinant of presence for these animal groups. It is concluded that continuity of forest cover, age of dominant trees, horizontal and vertical structures of vegetation should now be included in urban biotope classifications.  相似文献   
324.
随着人地关系的矛盾越来越突出,处理好经济发展与环境保护的关系,将两者高度融合,做到环境与经济的持续协调发展逐渐受到各方重视.以徐州市大沙河镇为例,在区域环境与经济发展协调度评价的基础上探索生态镇的建设模式.结果表明,2010年大沙河镇的环境综合发展指数为1.584,经济综合发展指数为1.182,环境与经济发展的协调度为0.88,处于良好协调状态.最后在评价结果的基础上分析了大沙河生态镇建设的模式.  相似文献   
325.
跨河大桥的建设对社会和经济的发展具有促进作用,但同时也会影响环境。正在建设的吴忠黄河公路大桥穿越吴忠滨河湿地,会对湿地的生态环境产生影响。文章介绍了吴忠黄河公路大桥和滨河湿地的基本概况,分析了大桥建设和营运对滨河湿地环境的影响,并提出了滨河湿地生态环境保护措施。  相似文献   
326.
于玲  宫赤霄  王忠 《环境技术》2008,26(2):36-40
本文中探讨的是根据绕组法计算电源变压器绕组温升的试验方法,以及对整个试验过程中环境、仪器设备、仪表、人为因素所引起的误差等对最终试验结果的影响,并对其测量不确定度进行评估。  相似文献   
327.
城市是区域经济发展的依托,区域旅游合作水平的高低同样与区域城市体系的发育程度紧密相关。以中部6省城市体系为构架,对中部6省省际间区域旅游合作进行了探讨,并从节点优化、线路组织、市场拓展等方面提出了6省间区域旅游合作的构想,以期为中部六省区域旅游合作程度的进一步加深提供一定的借鉴。  相似文献   
328.
节水型社会的建立是水资源可持续利用的必然选择。济南作为山东省的省会,水资源严重匮乏,人均水资源量只有357m^3,远低于国际公认的人均水资源量1000m^3的警戒线。济南以泉城闻名,但近年来面临泉水干涸的尴尬,节水对济南市而论就显得格外重要。根据实际情况选取一定量的节水型指标对济南市节水型社会构建情况进行了评价,得出济南市节水型社会水平处于良好阶段,提出了节水对策。  相似文献   
329.
山东省城市用地规模分布研究   总被引:1,自引:0,他引:1  
选取2002—2006年山东省48个城市建成区用地规模的资料,运用位序一规模法则分析了山东省城市建成区土地利用规模的变化,继而运用分形理论,阐释了位序—规模曲线。结果显示,山东省城市用地规模的均衡度趋向减小;城市用地规模的总量持续增加;城市体系整体发育,大城市发育快。根据曲线形态对城市用地规模进行分类,发现小城市的数量在逐渐减少,中等城市的数量在逐渐增加;首位城市济南市的用地规模尚有可观的发展潜力。  相似文献   
330.
环境行政强制包括环境行政强制措施和环境行政强制执行.在基层环境执法实践中,环境行政强制措施尤其是环境行政强制执行存在许多困惑和问题,拓展环境行政强制措施,给予环保部门一定的行政强制执行权是提高基层环境执法效率和遏制环境污染的有效途径.  相似文献   
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