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关中灌区是我省粮棉高产区,需肥量大。五十至六十年代除大量施用农家肥和少量化肥外,绿肥发展较多,它在粮棉增产上曾起了一定作用。七十年代化肥用量增多,复种指数日益提高,灌区绿肥处于被排斥的地位。目前不少人认为关中灌区已根本没有种植绿肥的必要和可能了。近年关中灌区化肥用量占全省总用量的四分之三,由于长期大量施用化肥,土壤有机质消耗过甚,化肥利用率越来越低。五十年代1斤标准氮肥平均增产小麦3斤,而目前大约只有1斤多,在经济上已不合算。因此,在增施化肥的同时,增加有机肥料的施用量是
Guanzhong Irrigation District is a high-yielding grain and cotton province, a large amount of fertilizer needed. In the 1950s and 1960s, besides extensive use of peasant manure and a small amount of chemical fertilizers, green manure has developed more and has played a role in increasing grain yield. Seventies increased use of chemical fertilizers, cropping index increased day by day, irrigated green manure was excluded status. At present, many people think Guanzhong Irrigation District has no need for planting green manure and may be. Guanzhong irrigation area in recent years, the amount of fertilizer accounted for three-fourths of the total amount of the province, due to long-term large-scale application of chemical fertilizers, soil organic matter consumed too much, more and more low fertilizer utilization. In the 1950s, 1 kg of standard nitrogen fertilizer increased wheat yield by an average of 3 kg, but at present only about 1 kg is economically uneconomical. Therefore, the increase in fertilizer at the same time, increasing the amount of organic fertilizer application