水是一种市场商品水的需求在空间和时间上的分配并不与自然界水的供给分配一致。这种分配上的差异需要空闻上靠输水建筑物调节,在时间上靠修建水库或者靠改变已有地表水或地下水的蓄水能力来调节。当这种调节可以经济地实现时,而且水质可以满足标准或可以经济地处理,则水就成为一种市场商品,成为与石油、天然 The distribution of the demand for water as a market commodity in space and time is not in line with the distribution of water in nature. This disparity in distribution needs to be regulated by delivery structures, by the time it takes to build reservoirs or by altering the water-holding capacity of existing surface or groundwater. When such an adjustment can be economically achieved and the water quality meets the criteria or can be economically dealt with, the water becomes a market commodity, a commodity that is compatible with petroleum, natural