摘要
以沂蒙山区的棕壤为例,利用野外原位模拟降雨试验,在分析比较5种典型覆被土壤结构稳定性的基础上,探讨不同土地覆被土壤结构稳定性对侵蚀泥沙全氮(N)、全磷(P)流失的影响。结果表明,土壤结构稳定性以山楂园和侧柏林较好,金银花和荒草地次之,花生地最差。不同土地覆被类型泥沙全N、全P流失特征差异明显,泥沙流失率与其全N、全P流失参量间具有显著的相关关系。土壤结构稳定性通过调节侵蚀产沙进而影响泥沙中N、P的流失特征,山楂园等土壤结构稳定性较好,侵蚀过程中更多地选择性搬运粘粒及精细颗粒,致使泥沙全N、全P流失量较少且含量和富集率较高;而花生地土壤结构稳定性较差,侵蚀过程中更多搬运砂粒及大团聚体破碎分散的细粒,使得泥沙全N、全P流失量较高且含量和富集率较低。泥沙全N、全P富集率在降雨过程中呈逐渐降低的变化,随着不同土地覆被类型土壤结构稳定性的降低,径流过程中泥沙全N富集率较全P的变化剧烈且下降幅度大。
Difference structure stability were detected for brown soil collected from five typical land covers in the Yimeng mountainous area,and then the effect of soil structure stability on the sediment loss of total nitrogen（N） and phosphorus（P） were investigated for different land covers with the aid of field in-situ rainfall simulation tests.Results showed that,the soil structure stability was the strongest for hawthorn and arborvitae,moderate for weeds and honeysuckle,and the weakest for peanut.There were significant differences in the characteristics of total-N,P sediment loss among the five land covers.The total N and P loss ratio in sediment had a significant correlation with sediment loss ratio.Soil structure stability affected the total N,P sediment loss by regulating the erosion and sediment.A better structure stability was detected in the topsoil of hawthorn,where more clay and fine particles were selective transported in the erosion process.That resulted in small loss and high content and enrichment ratio（ER） of sediment total N,P.Instead,more sand particles and small particles from the crush of macro aggregates were eroded at peanut,which had a worse structure stability and caused large loss with low content and ER of sediment total N,P.The ER of total N,P in sediment decreased increasingly in the rainfall-runoff process.With the deterioration of soil structure stability among different land covers,the ER of sediment total N changed much more greatly and had a larger decrease compared with total P during the runoff process.
出处
《水土保持学报》
CSCD
北大核心
2011年第4期12-16,共5页
Journal of Soil and Water Conservation
基金
教育部新世纪优秀人才支持计划(NCET-08-0877)
山东省科技攻关项目(2009GG10006015)
临沂市重大科技创新项目(201011019)
关键词
沂蒙山区
模拟降雨
土壤结构稳定性
侵蚀泥沙
氮磷流失
Yimeng mountainous area
rainfall simulation
soil structure stability
sediment
nitrogen and phosphorus loss
