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一、休闲原理夏季休闲可能是半干旱地区应用最广泛的一项农业技术措施。据估计(Greb,1979)在美国西部地区,休闲的麦地约有1,570万公顷,该地区由于受其降水—蒸发比率的制约,作物生长一直处于不稳定状况,所以采用对耕地休闲的办法来保证作物稳产是很必要的。世界上许多旱作农业发达的国家和地区的经验已证明:休闲是一种在一定时期内
First, the principle of leisure Summer leisure may be the most widely used in semi-arid areas of agricultural technology measures. It is estimated (Greb, 1979) that there are about 15.7 million hectares of recreational corn in the western United States, and crop growth has been precarious due to its precipitation-evaporation ratio constraints. Therefore, It is necessary to ensure stable crop production. The experience of many dry-agriculture developed countries and regions in the world has proved that leisure is a period of time