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土壤肥力是农作物高产的物质基础。但是,近几年来许多地方农田地力(即土壤肥力)严重下降。湛江地区1974年以来,32个点土壤养分演变的定位测定中,有机质下降的有21个点,平均下降率16％;全氮下降的有15个点,平均下降率24.2％;全磷下降的有8个点,平均下降39.6％;速效磷下降的有19个点,平均下降53.6％,速效钾下降的有30个点,平均下降率64％。不少农田在长期没有或
Soil fertility is the material basis for high-yielding crops. However, in many places, the land productivity (that is, soil fertility) in many places has seriously declined. Zhanjiang area since 1974, 32 points in the determination of soil nutrient evolution, organic matter decreased by 21 points, the average rate of decline of 16%; total nitrogen decreased by 15 points, the average rate of decline of 24.2%; decline of total phosphorus There are 8 points, an average decline of 39.6%; available phosphorus decreased by 19 points, an average decrease of 53.6%, available potassium decreased by 30 points, the average rate of decline of 64%. Many farmland in the long term or not