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甘肃省的气候属大陆性,在河西走廊和中部干旱地区,气候的荒漠性和半荒漠性更为突出。这些地区年平均气温为6~10度,年降水量为100~300毫米,而年蒸发量则达1,800~3,400毫米。全年风时较长,风级较大,夏季炎热。这些自然特点,是土壤盐碱化的主要原因,也使灌溉成为当地发展农业生产的必要条件。但是,在地下水位较高和自然排水条件不良的土地上进行灌溉时,又必须考虑土壤返盐的问题,否则,就要加快
The climate in Gansu Province is continental. In the Hexi Corridor and central arid areas, the desertification and semi-desertification are more prominent. The annual average temperature in these areas is 6 to 10 degrees with annual rainfall of 100 to 300 millimeters and annual evaporation of 1,800 to 3,400 millimeters. The wind is longer throughout the year, the wind is larger and the summer is hot. These natural features are the main reason for soil salinization and make irrigation a necessary condition for the development of agricultural production in the area. However, when irrigating land with high groundwater tables and poor natural drainage conditions, it is important to consider the issue of soil salinity, which would otherwise be exacerbated