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解放以来,北京地区粮食生产发展较快,1983年粮食总产达39.2亿斤,比解放初期的8.3亿斤提高了3.7倍。目前,平原水浇地面积已占95%,单位面积化肥用量也趋相对稳定,单纯依靠增水增肥已不能收到明显的效果,而且生产成本也高,70年代中期,复种指数达到一定值后,总产未能继续随复种指数呈正相关增长。另外,粮食生产水平在总的发展趋势中
Since the liberation, the grain production in Beijing has witnessed a rapid development. In 1983, the total output of grain reached 3.92 billion kilograms, an increase of 3.7 times over the 8.3 billion kilograms in the early days of liberation. At present, the area of irrigated land accounts for 95% of the total area, and the unit area of fertilizer use tends to be relatively stable. Relying solely on increasing water and increasing fertilizer can not receive obvious results, and the production cost is also high. In the mid-1970s, the multiple crop index reached a certain value After the total output failed to continue with the multiple crop index was positively correlated growth. In addition, the level of food production is in the general trend of development