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机构地区:[1]黑龙江八一农垦大学植物科技学院,密山158308
出 处:《中国农学通报》2002年第5期82-84,共3页Chinese Agricultural Science Bulletin
基 金:黑龙江省教委资助项目 (95 410 68)
摘 要:12年连续研究表明 ,轮作区与连作区白浆土中养分变化的总趋势相同。有机质和全磷变化不大 ,在土壤中均有所积累。全氮和碱解氮前 6年下降较多 ,后 6年趋于平衡。速效磷和速效钾提高很多。阳离子交换量 (CEC)稍有降低 ,pH变化不大。轮作区与连作区相比 ,轮作区土壤中碱解氮低于连作区 ,而连作区土壤中的速效钾高于轮作区。连作区中三大作物相比 ,小麦消耗土壤养分较少 ,大豆消耗土壤养分较多。随着种植年限的增加 。The research showed trend of nutrient variation is identical in rotation and continuous cultivation albic soils in twelve years Organic matter and total P have little variation,but content has accumulation Total N and available N have large decrease in first six years and tend to balance in second six years Available P and available K have obvious increased CEC has little decrease,but pH has little variation Content of available N in rotation soils is lower than continuous cultivation soils,but available K in continuous cultivation soils is higher than rotation soils Compared with three crops in continuous planting soils,fertility of land was consumed in wheat is littler than corn's and corn's is littler than soybean's With the planting year increasing,crop yield showed remarkable increasing in rotation
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