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介绍了声学多普勒流速剖面仪(ADCP)的主要工作原理,总结了太湖流域引江济太调水工作的需要,以水平式ADCP(H-ADCP)系统在苏州望亭水文站中的应用为例,对比分析了2009年引水、排水期间H-ADCP和人工监测的数据,总结了H-ADCP的使用特点,比测分析结果说明ADCP测流数据合理准确,可为今后防汛、水资源管理信息化建设提供借鉴。 相似文献
124.
受资源性缺水和水质性缺水影响,白洋淀湿地生态系统逐步退化。近年来,虽凭借应急调水,多次避免了干淀危机,但长期的资源性缺水,使淀区生态功能受到严重影响。南水北调中线工程的建设实施,为解决白洋淀生态缺水问题带来了机遇。通过在南水北调总体规划与水资源调度原则的基础上,对利用南水北调水补充白洋淀进行了研究,提出了江水补淀初步方案。 相似文献
125.
Optical investigations of Estonian and Finnish lakes 总被引:2,自引:0,他引:2
126.
根据国家湖泊(水库)营养状态评价标准及分级方法,运用等效数值评价法,建立湖库营养状态综合评价的等效数值模型,以云南省9大高原湖泊为例,对滇池等湖泊营养状态进行综合评价,并与主成分分析法及指数评价法评价结果作对比分析.结果表明该模型满足评价精度要求,是一种湖库营养状态综合评价的新方法. 相似文献
127.
鄱阳湖水文特性分析 总被引:3,自引:0,他引:3
The Poyang lake is currently the largest freshwater lake in China. Hydrologic properties of this lake, including precipitation, runoff, flood, sediment transport and so on have been analyzed on basis of large amount of measurements. Variation of these properties within a year and among years and the regional distribution are explored. The encounter probability of the outflow from Poyang Lake with that from Changjiang River is computed and the detention volume of Poyang Lake is analyzed. In accordance with water balance theory, the detention storage volume of Poyang Lake and Changjiang River corresponding to the annual maximum 60-day flood volumes in 9 typical heavy flood years of 1968, 1969, 1973, 1980, 1983, 1996 and 1998 have been calculated. The detention storage capacity of both the Lake and the River ranges from 5.6 billion to 16.5 billion m\+3, 11.5 billion m\+3 at average. Among which, the detention storage capacity of Poyang Lake is 9.5 billion m\+3, accounting for 82.6%. Poyang Lake has played a very important role in detaining floods from the five rivers of the Lake system as well as floods on the river section from Changjiang to Bali. There would have more frequent and more serious flooding on the middle and lower Changjiang River, especially in the region around Hukou if there were no Poyang Lake to detain and store the floodwater. 相似文献
128.
In arid regions, reductions in the amount of available agricultural water are fueling interest in alternative, low water-use crops. Perennial grasses have potential as low water-use biofuel crops. However, little is known about which perennial grasses can produce high quantity, high quality yields with low irrigation on formerly high-input agricultural fields in arid regions. We monitored biomass production, weed resistance, rooting depth, and root architecture of nine perennial grasses under multiple irrigation treatments in western Nevada. Under a low irrigation treatment (71 ± 9 cm irrigation water annually), cool-season grasses produced more biomass and were more weed-resistant than warm-season grasses. With additional irrigation (120 ± 12 cm water annually), warm- and cool-season grasses had similar biomass production, but cool-season species remained more weed-resistant. Among species within each grass type, we observed high variability in performance. Two cool-season species (Elytrigia elongata and Leymus cinereus) and one warm-season species (Bothriochloa ischaemum) performed better than the other tested species. Root depth was not correlated with biomass production, but species with deeper roots had fewer weeds. Abundance of fine roots (but not large roots) was correlated with increased biomass and fewer weeds. Both L. cinereus and E. elongata had deep root systems dominated by fine roots, while B. ischaemum had many fine roots in shallow soil but few roots in deeper soil. Cool-season grasses (particularly E. elongata, L. cinereus, and other species with abundant fine roots) may be worthy of further attention as potential biofuel crops for cold desert agriculture. 相似文献
129.
本文根据洞庭湖圩垸除涝排水系统非线性规划数学模型的特点,借助离散微分动态规划(DDDP)的思想,利用线性规划(LP)的修正单纯形解法,提出了一种既简单有效,又比较节省计算机时的新的求解非线性规划问题的直接解法——“迭代线性化方法”。实例验证该法是可行的。 相似文献
130.
滇池现代沉积物氨氮及磁化率研究 总被引:3,自引:0,他引:3
现代沉积物是湖泊营养盐和污染物的重要储藏库,在一定条件下,这些内源污染负荷可能成为水体富营养化的主导因子.研究通过对滇池(外海)现代沉积物中的氨氮、磁化率指标进行测试分析,研究结果表明:滇池现代沉积物中氨氮的高值区主要分布在北部海埂附近,中部略有增高,南部则最低,表层沉积物的氨氮含量低于下层;滇池现代沉积物的磁化率大小由滨岸带向湖心依次递减,在垂向上,磁化率随着深度的增加而增大.研究结果可为滇池污染治理提供了依据. 相似文献