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321.
Björn Scholz-Starke Richard Ottermanns Ursula Rings Tilman Floehr Henner Hollert Junli Hou Bo Li Ling Ling Wu Xingzhong Yuan Katrin Strauch Hu Wei Stefan Norra Andreas Holbach Bernhard Westrich Andreas Schäffer Martina Roß-Nickoll 《Environmental science and pollution research international》2013,20(10):7009-7026
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
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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
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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
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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
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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