【摘要】 对沈阳市苏家屯区露地和保护地土壤有效氮、磷、钾养分现状进行了调查 ,对露地土壤有效磷、钾在20年间含量变化进行了分析。结果显示 :露地土壤有效氮肥力水平较高 ,全区平均含量为98.96mg·kg-1 ;20年间 ,土壤有效磷含量递增 ,平均含量从1980年的4.96mg·kg-1 上升到2000年的11.61mg·kg-1;土壤有效钾呈递减趋势 ,平均含量从1980年的128.08mg·kg-1下降到2000年的79.90mg·kg-1,平均每年降低1.90%。保护地土壤有效氮、磷、钾含量随使用年限的增加呈上升趋势。更多还原

【Abstract】 A detailed survey was made for soil available nitrogen, phosphorus and potassium in agricultural fields and sheltered grounds in Shujiatun District,and a comparative study on the evolutionary trend of soil available P and K was made on the basis of the survey of soil nutrients in 1980.As for agricultural fields, the average content of available nitrogen was 98.96mg·kg-1 in 2000;the average content of available soil phosphorus had increased gradually from 4.96mg·kg-1 in 1980 to 11.61mg·kg-1 in 2000; a gradually decrease of available soil potassium was shown with a rate of about 1.90% per year from 128.08mg·kg-1 in 1980 to 79.90mg·kg-1 in 2000. As for sheltered grounds, the longer the sheltered ground was utilized, the higher the content of available N, P and K.更多还原