The data of soil nutrients in agriculture land from 190 monitoring sites for more than 20 years was investigated based on different regions.The results showed that the soil organic matter during 1986～1997 for different areas presented variouse change trends,increasing trends for Zhongnan and Huabei,whereas decreasing trends for Huadong and Dongbei,stable trends of various areas during 1998～2006.The content of total N,avlaible N presented similar change trends with the content of organic matter,the relationship was significant among them.The content of soil available P for different regions increased with experimental years.The content of soil available K stabilized during 1986～1997 except Xibei area.The content of available K stablized during 1998～2006 for all research areas.In a words,the content of available P presented increasing trends for various regions,others indexes of soil nutrients exsited a definitely difference with different regions.%对我国东北、西北、华北、西南、中南和华东地区农田的190个土壤质量监测点20多年来的土壤养分观测数据进行区域统计分析,结果表明,中南、华北区耕层土壤有机质含量在1986～1997年有显著的上升趋势,华东、东北区有下降趋势,西北、西南区基本稳定;1998～2006年各区变化不大,基本平稳.全氮、碱解氮与有机质含量变化存在显著相关关系,变化趋势也基本一致.20年来不同地区耕层土壤有效磷含量各区域均稳中有升.1986～1997年除西北耕层土壤速效钾含量有一定的下降趋势外,其他区域基本稳定;1998～2006年,土壤速效钾的平均含量变化也不大.总之,不同地区的土壤有效磷呈稳中有升的趋势,其它土壤养分指标不同地区存在一定的差异.
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