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平原积雪作为水源,对于干旱半干旱地区十分重要。美国农业部于50年代中期就开始对其中央大平原半干旱区积雪的农业利用及管理进行试验研究,研究持续了24年,新近提出了一些新的、较为全面的成果,这些成果具有普遍意义和参考价值。 美国中央大平原位于北纬39°以北,属寒冷半干旱气候区。积雪是这里水分平衡的重要组成部分,农田和牧场每年获得雪水181亿立方。大平原的降雪由东南向西北逐
Plain snow as a source of water, for arid and semi-arid areas is very important. In the mid-1950s, the USDA started pilot studies on agricultural use and management of snow cover in the Central Plains semi-arid region. The study lasted 24 years and recently proposed a number of new and more comprehensive results that are prevalent Meaning and reference value. The Central Plains of the United States is located north of latitude 39 ° and belongs to a cold and semi-arid climate zone. Snow cover is an important part of the water balance here, with 18.1 billion cubic meters of snow and water being harvested every year on farmland and rangeland. The Great Plains snowfall from southeast to northwest by