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我国的干旱地区一般系指贺兰山及乌鞘岭以西的广大地区。多年平均降雨量不超过250毫米,西部的平原地区多在50—150毫米,塔克拉玛干沙漠在25毫米以下,还有多年不雨的地方。而且多年平均蒸发量都在1400毫米以上,尤其西部沙漠地区更高,可达2000—3000毫米。植物生长严格受水源条件的限制,自古以来发展的是灌溉农业。即使在如此降雨稀少的干旱地区,在一定的自然地理环境下地表水亦比较充足,在特定的水文地质条件下地下水则比较丰富,这对发展干旱地区的农林牧业,治沙改土都是有利的。我国干旱沙漠地区的地下水受着地质构造条件和自然地理环境所制约。高山区由于降水较多,成为干旱地区水资源的发源地。相对沉降的大型构造盆地,堆积在巨厚的第四纪松散地层中,蕴藏着丰富的地下水,
Arid areas in our country generally mean the vast areas to the west of Helan Mountain and Wushaoling. Average annual rainfall does not exceed 250 millimeters, mostly in the western plains at 50-150 millimeters, the Taklamakan Desert at 25 millimeters or below, and many years without rain. And for many years the average evaporation is more than 1400 mm, especially in the western desert higher, up to 2000-3000 mm. Plant growth is strictly limited by the conditions of the water source, since ancient times the development of irrigation agriculture. Even in such arid areas where rains are scarce, surface water is abundant under certain natural and geographical conditions and groundwater is abundant under certain hydrogeological conditions. This is true for the development of agriculture, forestry, animal husbandry and desertification in arid areas advantageous. The groundwater in the arid desert region of China is subject to the geological conditions and natural geographical environment. Due to more precipitation in high mountain areas, it has become the cradle of water resources in arid areas. Relatively subsidence of the large tectonic basins, piled up in thick Quaternary loose strata, rich in groundwater,