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1、什么叫水资源?广义地说,自然界所有的以气态、固态和液态三种形式存在的水统称水资源。包括大气水、海洋水、湖泊水、河流水、土壤水、地下水、冰川水和生物水。这些水的总量约14.5亿立方公里。假如平铺于地球表面,其平均水深可达2800米。然而,地球上绝大部分水是不宜于人类使用的。海洋水占地球总水量的94%,因含盐分太高(每升含盐量35克),不能为人们直接使用。陆地上淡水资源量约2800万立方公里,占总水量的2%,而其中冰川水约有2400万立方公里,古淡水资源量的85%,主要分布在南北极,开发利用十分困难。比较容易开发利用的淡水资源,即通常所讲的水资源,指可以不断循环更新的河流水、湖泊水、地下水和土壤水的动态水量,总量约400万立方公里。仅占地球总水量的千分之三。由于这些水量的
1, what is water? Broadly speaking, all the water in nature in the form of three forms of gas, solid and liquid collectively referred to as water resources. Including atmospheric, ocean, lake, river, soil, ground, glacial and biological waters. The total amount of water is about 1.45 billion cubic kilometers. If tile on the surface of the earth, the average depth of up to 2800 meters. However, most of the earth’s water is unfit for human use. Ocean water accounts for 94% of the Earth’s total water, because salt content is too high (35 grams per liter of salt content), can not be used directly for people. Fresh water resources on land about 28 million cubic kilometers, accounting for 2% of the total water, of which about 24 million cubic kilometers of glacier water, ancient freshwater resources, 85%, mainly in the North and South Poles, development and utilization is very difficult. The relatively easy to develop and utilize freshwater resources, commonly referred to as water resources, refer to the dynamic water volume of river, lake, groundwater and soil water that can be constantly recycled and updated. The total amount is about 4 million cubic kilometers. Only three-thousandths of the earth’s total water. Due to the amount of water