我国耕地土壤养分变化与肥料投入状况

根据全国耕地地力监测点 10余年监测结果 ,分析了我国耕地土壤养分变化与肥料投入状况。结果表明 ,有机肥投入量有逐渐减低的趋势 ,而化肥投入量稳中有升 ;常规施肥区土壤有机质、速效氮、速效钾年度间基本稳定 ,而速效磷稳中有升 ;空白区土壤有机质、速效氮基本稳定 ,速效磷、速效钾有下降趋势。养分收支平衡分析表明 ,氮磷盈余、钾亏缺。氮盈余量北方旱地、南方旱地和水田随年度稳中有升 ,而北方水田逐渐下降 ;磷盈余均稳中有升 ;钾亏缺南方水田在缓解 ,而其他农田在逐渐加大

Changes of soil nutrient contents and input of nutrients in arable of China

s: The changes of soil nutrient contents and input of nutrients in arable of China were analyzed according to the results of long?term measure of soil nutrient and recordation of fertilization in fixed location (National Soil Fertility Monitoring) from 1985 to 1997. The results showed that the rate of manure was decreased and the rate of chemical fertilizers was increased slightly. From 1985 to 1997, in fertilization plot, the contents of soil organic matter, available N and K were stable, available P was increased slowly, but in control plot, the contents of soil available P and K were decreased. The input and output balance of N and P was positive, but K was negative. From 1985 to 1995,the surplus of N was stable in dry land and south paddy field, and decreased in north paddy field, the surplus of P was increased slowly, and the negative balance of K was decreased in south paddy field, but increased in other fields.