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31.
Industrial and agricultural effects on water environment and its optimization in heavily polluted area in Taihu Lake Basin, China 总被引:1,自引:0,他引:1
The deteriorating water quality in the Taihu Lake Basin has attracted widespread attention for many years, and is correlated with a sharp increase in the quantity of pollutant discharge such as agricultural fertilizers and industrial wastewater. In this study, several factors were selected for evaluating and regionalizing the water environmental capacity by ArcGIS spatial analysis, including geomorphologic characteristics, water quality goals, water body accessibility, water-dilution channels, and current water quality. Then, the spatial optimization of agriculture and industry was adjusted through overlay analysis, based on the balance between industrial space and water environmental capacity. The results show that the water environmental capacity gradually decreases from the west to the east, in contrast, the pollution caused by industrial and agricultural clustering is distributes along Taihu Lake, Gehu Lake and urban districts. The analysis of the agricultural space focuses on optimizing key protected areas of the Taihu Lake Basin, and the shores of Gehu Lake, optimally adjusting the second protected areas of the Taihu Lake Basin, and generally adjusting the urban areas of Changzhou and Wuxi cities. The analysis of industrial space focuses on optimizing the downtowns of Changzhou and Wuxi cities, optimally adjusting key protected areas and second protected areas of the Taihu Lake Basin, and generally adjusting the south and southwest of Gehu Lake. Lastly, some schemes of industrial and agricultural layouts and policies for the direction of industrial and agricultural development were proposed, reflecting a correlation between industry and agriculture and the water environment. 相似文献
32.
中国地市工业集聚与污染排放的空间特征及计量检验 总被引:4,自引:6,他引:4
采用空间分析和计量模型等方法,研究中国285个地级及以上城市工业集聚和污染排放的空间特征及内在关系,结果表明:① 工业集聚与污染排放的重心分布、轨迹、距离、速度差异较大。东部的工业集聚水平高于中西部,工业污染中西部更突出。工业集聚与污染排放总体呈负相关关系,局域上分为低高、高低、低低3种关联类型。② 工业集聚在全国及东中西部均有利于降低工业污染,但是对不同区域减排作用的大小有所不同,作用由大到小依次是西部、中部和东部。③ 对于工业污染的防治,应继续走集聚化道路。东部要优化产业结构,控制合理的集聚规模;中西部应加强产业集聚,提高技术溢出的污染减排效应。 相似文献
33.
膜生物反应器技术与市场的发展 总被引:1,自引:0,他引:1
膜生物反应器(MBR)作为一项新型的水处理技术,具有处理效率高、出水水质好、运行管理简单等特点,在水处理领域包括自来水供给保障和污水处理回用中得到了迅速发展。文中从技术发展和市场开发两方面对MBR的现状作了扼要评论,通过历史进展的回顾,着重分析了影响MBR发展的一些关键因数,展望了MBR在市政污水和工业废水处理回用中的发展前景。 相似文献
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Speciation, distribution, and potential ecological risk assessment of heavy metals in Xiamen Bay surface sediment 总被引:3,自引:1,他引:3
Based on the survey of surface sediment in Xiamen Bay in October 2011, the speciation, distribution, and potential ecological risk assessment of heavy metals (Cu, Pb, Zn, Cd, and Cr) in this area were studied us-ing the sequential extraction method and ecological risk assessment method. The results indicated:(1) the total concentrations of these heavy metals were influenced by runoff, industrial wastewater, and sewage, and were all higher in the coastal area than the offshore area while the highest area of Pb was a little far-ther away from the coastal water due to atmosphere deposition;(2) sequential extractions suggested that Cu was mainly composed with residual and Fe/Mn-oxide bound fractions, Pb was bound to Fe/Mn-oxide, Zn and Cr were dominated by residual, and Cd bound to exchangeable and carbonate fractions; (3) the order of migration and transformation sequence was Cd>Pb>Cu>Zn>Cr and the degree of pollution was Cd>Pb>Cu>Zn>Cr;and (4) the ratios of the secondary and primary phases showed that Zn and Cr were both clean, Cu may be polluted, Pb was moderately polluted, while Cd was heavily polluted. 相似文献
38.
解决我省城市水资源紧缺问题有以下对策:(1)建立水资源管理模型,实施最优化开采方案;(2)防治水污染,实行废水资源化,对城市工业废水净化处理再利用;(3)实行地表水地下不相互调剂;(4)拦蓄降水和地表弃水,开发人工补给,建立地下水库;(5)建立节水型社会生产体系。 相似文献
39.
The process of adsorption of metal ions by immobilized marine algae with the existence of clay was investigated. It can be noted from the results that, after mixing with clay, the adsorption rate increases rapidly with the increasing amount of the marine algae. When pH=5, the best ratio between the clay and the marine algae is 1:4 for Pb^2+. The result of in situ handling of the waste water containing heavy metals shows that the average adsorption rates of heavy metal irons Cu^2+, Cd^2+, Pb^2+ and Ni^2+ are all over 70 %. 相似文献
40.
研究了热致死小球藻对微量Cr^3 的生物吸附富集和机理。结果表明,培养72h左右的热致死小球藻吸附富集Cr^3 的能力最强;当pH为4.5—5.0,藻浓度为1—2g/L时,死体藻对Cr^3 有较好的生物吸附作用;随着Cr^3 浓度增加,单位质量藻的Cr^3 吸附量呈上升趋势,但其Cr^3 吸附率却急剧下降。热致死小球藻对Cr^3 的吸附可以用Freundlich模型描述,拟合方程为:q=5.3369C11/2.6295,R^2=0.9974;在生物吸附的起始阶段,藻体对Cr^3 的吸附较快,40min左右时藻体达到最大吸附量。 相似文献