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苏北黄淮冲积平原的沙性土,其特性为爽水快,肥效速,肥力不长,作物既易疯长,又易脱力.过去沙土上三麦亩产100斤左右,玉米150～200斤,大豆也不过250斤.1958年土壤普查时,沙土的有机质一般在1%以下,大部分在0.5%左右,也有个别青沙土达1.2%,全氮量为0.034～0.057%,代换量5.8毫克当量/100克土.1964年开始旱改水,在定向培育下,平整了田块,改种了水稻,大力推广种植绿肥,积极
Northern Shaanxi Huanghuai alluvial plain sandy soil, its characteristics Shuangshui fast, fertilizer efficiency, fertility is not long, the crop is not only easy to grow long, easy off force in the past three acres of sand on the mu yield of about 100 pounds, corn 150 to 200 pounds , But also 250 kg of soybeans .1958 Soil Census, sandy soil organic matter is generally below 1%, most of the 0.5%, there are individual Qingsha soil up to 1.2%, total nitrogen 0.034 ~ 0.057%, substitution 5.8 Milligrams per equivalent / 100 grams of soil .1964 drought began to change water, under directional cultivation, the formation of plots, replanting of rice, vigorously promote the planting of green manure, active