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101.
为提升引调水工程的环境改善效果,须对水体的自身连通水平、水质现状、水环境主要影响因子进行分析。以太湖流域跃进联圩为研究对象,利用图论连通度理论对研究区域静态基流连通性进行评价,探索圩内水系连通性的空间差异及变化特性。同时,开展短期引调水实验,结合模糊综合分析法评价引调水带来的圩内水质变化情况及规律,研究圩内水环境和水系连通性的响应关系。结果表明,模糊综合评价法在引调水环境改善分析中具有适用性,可实现对圩内各监测点位水质变化的全面分析;水体流动性是影响圩区内水质的重要环境因素,高锰酸盐指数是导致圩内水质恶化的主要影响因子。引调水工程对圩区水环境具有一定的持续改善性作用,但对基流连通性较差的区域,改善效果有限。 相似文献
102.
选取引江济太工程中长江来水进入太湖第一站的贡湖湾为研究对象,基于2011年11月~2013年8月在贡湖湾的逐月野外调查,同时以湖心水域为参考,探讨引江济太对湖体N2O通量的影响.结果表明,贡湖湾N2O排放通量要显著高于湖心排放量,其N2O通量均值分别为6.9,2.1μmol/(m2·d),但在非引水期间2个湖区的N2O通量无显著差异.贡湖湾和湖心N2O通量呈现明显的季节变化,且均与水温呈显著负相关关系,但因受外源来水的影响,贡湖湾N2O通量的温度依赖程度相对较低.另外,2个湖区的N2O通量还与营养盐等因素有关.总体上,外源引水提高了贡湖湾N2O排放通量,但考虑到湖泊N2O通量受到内部和外部因子的综合协同影响,外源引水对湖泊N2O通量的具体调控机理还需要进一步探讨. 相似文献
103.
根据黑河草滩庄引水枢纽闸上游泥沙冲淤情况 ,分析了局部冲刷、泥沙淤积和上下游输沙不平衡等对生态环境的影响 ,提出了改善生态环境的具体工程措施 相似文献
104.
George A. Whetstone Ernst W. Kiesling 《Journal of the American Water Resources Association》1971,7(4):684-688
ABSTRACT .The major purpose of existing and proposed diversions of water to the Prairies is for irrigation. Being flat lands adaptable to mechanized agriculture and possessing a good network of rail and highway access, they are well suited for such use. Wheat surpluses, currently a serious problem in Canada, can be expected to melt under world population pressures and conversion of wheat lands to other crops with the advent of irrigation. The water sources envisaged are in the Canadian Arctic watershed with the United States purchasing Canadian water at the boundary. There is an increasing interest in the Canadian Prairie Provinces in regarding water as a commodity and selling some of it to pay for the development required to put the portion retained in Canada to use. 相似文献
105.
W.F. Rannie 《Journal of the American Water Resources Association》1980,16(2):207-214
ABSTRACT: The 1950 flood disaster in the Red River Valley, Manitoba, and particularly in Winnipeg made all levels of government aware of the need for control measures. The principal elements of the system which was implemented were two large excavated diversion channels, a storage reservoir, and ring dykes around several small communities. In terms of cost and size, the flood control system is the largest in Canada and despite Federal contributions amounting to nearly 60 percent of the final cost, it represented a considerable fiscal burden for the comparatively small population of Manitoba. Between the opening of the Red River Floodway in 1968 and 1979, a series of exceptional spring peak flows on the Red and Assiniboine Rivers demonstrated the benefits of such a system to a degree which could not have been anticipated at the time the projects were being considered. Furthermore, maximum spring discharges from 1913 to 1978 show a clear rising trend, indicating that the flood hazard is becoming even more severe than was initially assumed; if this trend continues, future benefits will continue to exceed expectations. The overall effectiveness of the hazard reduction program in the Red River Valley, however, has suffered from continued development in unprotected areas. Recent federal-provincial agreements have been reached which will substantially reduce this problem and place greater emphasis on improving the non-structural components of an overall flood hazard reduction program. 相似文献
106.
107.
防洪保护及污水资源化工程对滇池环境保护的适用研究 总被引:1,自引:0,他引:1
滇池外海与草海分隔后,通过合理的调控,水资源是平衡的,且增加出口可从隧洞分洪达40/S,满足20年一遇分洪要求;工程运行将使滇池水质有所改善,对局部水域水质将会有较大改善;出水排入沙河使其失去饮用水功能,水生态环境变劣,而对螳螂川影响不明显;二期工程(三个水库的建设)使排水得到利用,产生一定的综合效益。 相似文献
108.
ABSTRACT: To manage the first flush of storm runoff in urbanized areas, a diversion box and detention basin system has been proposed for a new storm sewer system or for retrofitting an existing system. A software package for a personal computer has been developed to facilitate the analysis and design of the system. Hydrographs and pollutographs are generated at the inlet and outlet of the diversion box and the detention basin. The peak outflow and peak pollutant concentrations are compared with the allowable outflow and pollutant concentration for urban stormwater quantity and quality management. The model is developed for both analysis and design purposes. 相似文献
109.
若干人工调控措施对富营养化湖泊藻类种群的影响 总被引:26,自引:5,他引:26
在太湖用围隔试验,研究湖泊底泥稳外源污染对富;营养化湖泊藻类种群的影响,结果表明,在没有底泥和外源污染(相于当彻底清淤和截污)的情况下,围区内(200m^2)水体氮磷浓度均有明显下降,但藻类生物量却急剧上升,且出现“藻华”,结合南京玄武湖和杭州西湖的截污、清淤挖泥、引水冲污等富营养化防治措施的实际效果分析,探讨了截污、清淤、引水冲污对营养几湖泊藻类种群的影响,指出对严重富营养化的湖泊,单纯采取截污 相似文献
110.
ABSTRACT. This work evaluates the economic losses due to diversion from the Snake River during the relatively low-flow year May 1928-April 1929. The results determine the losses due to pollution abatement and power generation for several different patterns and volumes of diversion, and the tool of analysis is dynamic programming. 相似文献