THE INFLUENCES OF PRECIPITATION RESOURCE ON GRAIN CROP YIELD IN DRY AREAS OF WESTERN HENAN PROVINCE AND THE COUNTERMEASURES
豫西地区降水资源对旱地粮食作物产量的影响与对策

This paper quantitatively expounds that the precipitation resource is one of the important factors that affect the fluctuation of the grain crop production in the dry areas of Western Henan Province. On the basis of the calculation results of crop water surplus and shortage during various growing periods and the critical period of water requirement in normal precipitation years, high precipitation years and low precipitation years of 19 counties or municipalities in Western Henan Province, the basic law of the influences of precipitation resource on grain crop production in dry areas is revealed. According to the randomness of water variation and the option of cropping system in dry areas, the macro countermeasures that use the geographic risk policy making and practise the water adaptability planting are expounded in this paper.