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依据淮河中游1998~2007年的水质监测数据,研究淮河中游水质近10 a的时空变异,并采用有机污染综合指数对水质污染状况及趋势进行评价分析,结果表明:淮河中游水质呈逐渐改善的趋势,说明全流域水污染治理已经取得了一定成效,但是,年内水质季节性差异较大,枯水期水质污染依然严重,多数处于中等污染或是严重污染状态;水体最主要的污染物为氨氮;淮河中游的上段水质要好于下段,淮南大涧沟段和吴家渡段为淮河中游的重点污染区域和主要污染物输入区域。  相似文献
2.
Three stochastic mathematical models for calculation of the reservoir flood regulation process, river course flood release, and flood risk rate under flood control were established based on the theory of stochastic differential equations and features of flood control systems in the middle reach of the Huaihe River from Xixian to the Bengbu floodgate, comprehensively considering uncertain factors of hydrology, hydraulics, and engineering control. They were used to calculate the flood risk rate with flood regulation of five key reservoirs, including the Meishan, Xianghongdian, Nianyushan, Mozitan, and Foziling reservoirs in the middle reach of the Huaihe River under different flood frequencies, the flood risk rate with river course flood release under design and check floods for the trunk of the Huaihe River in conjunction with relevant flood storage areas, and the flood risk rate with operation of the Linhuaigang Project under design and check floods. The calculated results show that (l) the five reservoirs can withstand design floods, but the Xianghongdian and Foziling reservoirs will suffer overtopping accidents under check floods; (2) considering the service of flood storage areas under the design flood conditions of the Huaihe River, the mean flood risk rate with flood regulation of dykes and dams from Xixian to the Bengbu floodgate is about 0.2, and the trunk of the Huaihe River can generally withstand design floods; and (3) under a check flood with the flood return period of 1 000 years, the risk rate of overtopping accidents of the Linhuaigang Project is not larger than 0.15, indicating that it has a high flood regulation capacity. Through regulation and application of the flood control system of the Linhuigang Project, the Huaihe River Basin can withstand large floods, and the safety of the protected area can be ensured.  相似文献
3.
为揭示淮河上中游流域日照时数时空变化特征及突变情况,基于1960~2014年日照时数资料,采用气候倾向率、Mann-Kendall趋势与突变检验、滑动t检验、克里金插值等方法,对流域日照时数的时空变化特征进行剖析。结果表明,淮河上中游流域近55年来日照时数以20世纪80年代为界由多变少,其中年日照时数大约每10 a减少102.2 h,四季日照时数的气候倾向率排序为夏(-48.8 h/10a)、冬(-29.3 h/10a)、秋(-19.7 h/10a)、春(-5.4 h/10a)。流域日照时数的减小趋势除春季不显著外,年与夏、秋、冬三季的日照时数均呈现出显著的减少趋势。空间上,流域北部的中间地带(商丘站附近)与西北部(宝丰、郑州站附近)的日照时数减小趋势较明显(Z<-2),减少幅度较大,而东部(盱眙站除外)减少幅度则偏小。年与夏季日照时数的极显著突变年份为1980年,年日照时数的弱显著突变年为1984年。秋季、冬季的突变年份分别为1999年、1983年,春季的突变年份在20世纪70年代内。研究成果可为淮河上中游流域的气候研究、农业生产等提供科学研究依据。  相似文献
4.
刘义国 《水资源保护》2007,23(1):43-44,48
淮河干流中游未控区间的天然径流是历次水资源评价的难点。在对1980~2000年天然径流系列进行逐项还原的基础上,将其计算结果与第一次评价的1956~1979年成果进行对比分析;对同步期1956~2000年的径流成果进行简单介绍。经与同步期多年平均天然径流深等值线图对照,反映本次同步期天然径流评价成果基本合理,可作为水资源评价的依据。  相似文献
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