论文部分内容阅读
1.提供安全饮用水,是农业地区一个迫切需要解决的问题.据世界卫生组织1980年统计,能得到清洁饮用水的城市和农村人口别为75%和29%。2.工,农业进一步发展对水需求增加从全球分析,农业用水占全球耗水量的80%,工业用水各国不同,加拿大占全部取水的84%,美国占40%,印度只占19%。预计1990年世界总灌溉面积2.73亿公顷。工业生产中的排污和热污染对水质也是个问题。水电是水资源开发主要目标之一,现在有的国家已占能源构成的70%,甚至近100%。
1. Providing safe drinking water is an urgent problem to be solved in agricultural areas, and according to the 1980 statistics of the World Health Organization, 75% of urban residents and 29% of rural residents have access to clean drinking water. 2. Industry and agriculture further develop demand for water From a global analysis, agricultural water accounts for 80% of the global water consumption, industrial water varies from country to country, Canada accounts for 84% of total water withdrawal, the United States accounts for 40% and India only accounts for 19%. The world’s total irrigated area of 273 million hectares is estimated in 1990. Sewage and thermal pollution in industrial production is also a problem for water quality. Hydropower is one of the main goals of water resources development. Now some countries account for 70% or even nearly 100% of the energy composition.