随着我国城市与交通工矿事业的发展对土地的占用，以及我国人口的持续增长，特别是人们生活水平的改善、食物结构的改变对粮食、肉类、牛奶、禽蛋消费与需求的不断增加，这些都迫切地要求我们因地制宜合理利用土地资源，并适时地调整粮食与饲料作物种植结构，引进并发展适应性 With the occupation of land by the development of cities and transportation and mining industry in our country and the continuous growth of population in our country, especially the improvement of people’s living standard, the food structure and the consumption and demand for food, meat, milk and eggs are constantly increasing due to the change of food structure All of these urgently require us to make rational use of land resources in accordance with the local conditions and adjust the planting structure of crops for food and fodder in a timely manner so as to introduce and develop adaptive