汶川地震区新生水土流失对土壤养分的影响

采用野外调查和室内分析相结合的方法,研究汶川地震区新生水土流失对不同恢复类型样地土壤养分的影响。结果表明:(1)地表裸露、自然恢复和人工种植类型样地pH高于对照样地,各种恢复类型间土壤有机质含量差异显著。(2)土壤全氮含量在人工种植、对照样地处于丰富状态,在地表裸露、自然恢复样地处于贫瘠状态,铵态氮含量在对照样地最高,硝态氮在新生水土流失作用下流失严重。(3)土壤全磷含量在地表裸露和自然恢复样地低于人工种植和对照样地,通过降雨-地表径流、渗漏淋失等途径流失,速效钾含量均处于缺乏状态。(4)土壤全钾含量在对照样地最大,自然恢复样地最小,各种恢复类型样地速效钾含量基本处于缺乏水平,人工种植样地由于培肥的作用速效钾含量得到提升。

Effect on Soil Nutrient Situation of Water and Soil Loss Made by Earthquake in Wenchuan Zone

This article studied impact of soil erosion on soil nutrient of different restored types in Wenchuan earthquake zone using the field investigation and laboratory analysis methods.The results showed:(1)Compared with control plot,the soil pH value of bare land,natural restored land and cultivated after the earthquake were higher,and the organic matter was significantly different among all restored types.(2)Total nitrogen was rich in soil of cultivated after the earthquake and control plot,but poor of natural restored land and bare land.Ammonium-N was richest in control plot soil compared to the other types.Nitrate-N decreased heavily as result of the water and soil loss made by earthquake.(3)Phosphorus loss by runoff,leaching loss and other ways.Soil total phosphorus was richer in control plot and cultivated after the earthquake than bare land and natural restored.And soil of all types was lack of available phosphorus.(4)Compared with all types,total potassium was abundant in control plot soil,but deficient in natural restored land.The phenomenon that available potassium was absent in all kinds of restored types soil,while it was increased in soil of cultivated after the earthquake by applying fertilizers.