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前言人们生活的先决条件是经常不断地利用淡水。淡水资源来自于聚积在地面上的雨水和地表下不同深度的地下水。但是,世界许多地方,这种资源还不能满足人们对水的基本需要,或者是太昂贵了。有的地方采用经过脱盐的海水或脱盐的地下矿化水或许是解决供水不足问题的一种方法。然而,确保经常不断地供水的传统办法,是把水聚积在地面水库里。但这种办法在气候干燥的地区却是一个问题。在这些地区,贮存在水库中的水,大部分会蒸发而散失,并由于沉淀物质淤积水库,使其有效率降低。在这些地区,一般都有迅速、短暂而强烈的地表径流,又引起有关水坝设计的种种问题,在地形平缓,堤坝必须长或大的地方尤其如此。用地面筑坝来蓄水的最后一个值得注意的潜在问题是水的污染而随水传播疾病的危险。
Preface It is a prerequisite for people’s lives to make constant and fresh use of fresh water. Freshwater resources come from rainwater that accumulates on the ground and underground water at different depths. However, in many parts of the world, such resources do not yet meet people’s basic needs for water or are too expensive. Using desalinated seawater or desalinated underground mineralized water in some places may be one way to address the problem of inadequate water supply. However, the traditional way of ensuring regular and constant water supply is to accumulate water in surface reservoirs. However, this solution is a problem in the dry climate. In these areas, most of the water stored in reservoirs evaporates and is lost, and sedimentation of silt reservoirs depresses the efficiency of the reservoirs. In these areas, there are generally rapid, transient and intense surface run-off that raises questions about the design of the dam, especially where the terrain is flat and the dykes must be long or large. The last notable potential problem with ground dam dams to store water is the danger of water pollution that spreads with the water.