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邓县常年植棉25万亩左右,70%的棉田为麦棉两熟制。由于植棉集中,多年连作,倒茬困难,加之种地养地的措施跟不上,虽然化肥施用量不断增加,但结果是地越种越瘦,土壤营养成份比例日趋不合理。据1985—1987年三年土壤化验结果表明,土壤有机质含量平均每年以14.5%的幅度递减,速效N含量平均每年以19.3%的幅度递减,速效K含量平均每年以33.6%的幅度递减,只有速效P含量平均每年递增64%,
Deng County cotton planting about 25 million mu all year round, 70% of cotton fields for the two cotton crop. Due to the concentration of cotton, continuous cropping for many years, stubble difficult, coupled with the measures to keep up the land farming, although the increasing use of chemical fertilizers, but the result is more and more lean, the proportion of soil nutrients increasingly unreasonable. According to the results of soil tests from 1985 to 1987, soil organic matter content decreased by an average of 14.5% annually, the available N content decreased by an average of 19.3% annually, and the available K content decreased by an average of 33.6% per year. P content average annual increase of 64%