1山西冬麦区玉米复播的必要性1.1确保粮食安全的需要山西地处秦晋黄土高原,境内地形起伏颇大,热量和降水分布不均匀,粮食生产水平低而不稳;加上近年国家在黄土丘陵区实施的大规模退耕还林政策,部分粮食品种的自给问题不能解决,每年需要从周边省份大量调入。所以在粮食安全问题? 1 Shanxi Winter Wheat Necessity of Replanting 1.1 Needs to Ensure Food Security Shanxi is located in the Qin and Jin Loess Plateau, the territory of undulating terrain, heat and precipitation unevenly distributed, low and unstable grain production level; coupled with the recent years in countries Large-scale policy of returning farmland to forests in the loess hilly region will not solve the problem of self-sufficiency of some grain varieties and will require a large amount of transfers from neighboring provinces each year. So in food security?