摘要
在土壤侵蚀严重的黄土高原地区,选择3种土地利用类型(坡耕地、灌木林地、草地),利用放射性同位素137 Cs示踪技术分析了坡面尺度土壤侵蚀程度的变化,明确了土壤重金属(Mn、Cr、Zn、V、Ni、Cu、As、Co)在流域内的空间分布特征,分析坡面侵蚀速率变化与土壤重金属再分布的响应关系.结果表明,坡耕地总体上为"强烈侵蚀",最大侵蚀速率高达10 853.56t·km-2·a-1.灌木林地和草地为"轻度侵蚀".坡耕地Cr和As含量较高,而V、Mn、Zn、Co、Ni、Cu在灌木林地和草地含量较高.坡耕地土壤重金属的分布与侵蚀速率相反,侵蚀严重的地区,土壤重金属含量少,侵蚀微弱的地区,土壤重金属含量高.侵蚀作用下坡耕地中Cr、V、As、Co和Zn容易发生顺坡迁移流失.土地利用变化和侵蚀过程对坡面土壤重金属分布影响较大,本研究结果可为控制水土流失,减少重金属面源污染提供重要的科学依据.
Changes in land-use are known to have impact on hydrological processes and heavy metal migration,but the corelation between soil erosion and soil heavy metal has not been studied in detail.Soil erosion on the slope of three land use types(sloping cropland,shrubland and grassland)in the Losses Plateau of China was investigated with 137Cs tracking.The distribution of eight heavy metals(Mn,Cr,Zn,V,Ni,Cu,As and Co)in the watershed was also studied.Correlation between soil erosion rate and soil heavy metal distribution was examined.Soil erosion in sloping cropland was strong and max soil erosion was at 10 853.56 t·km-2·a-1.Soil erosion in shrubland and grassland was slight.Sloping cropland showed higher Cr and As concentrations than shrubland and grassland.V,Mn,Zn,Co,Ni and Cu contents were higher in shrubland and grassland than in sloping cropland.The distribution tendency of heavy metals in sloping cropland was similar to soil erosion.Heavy metal contents in sloping cropland were high in area with low soil erosion but low with high soil erosion rate.Cr,V,As,Co and Zn were lost with water erosion along the slope in sloping cropland.Changes in land use and soil erosion had effects on distribution of heavy metals in soil.This work provides some scientific basis for soil and water erosion control and for the control of non-point heavy metal pollution.
作者
李琦
时鹏
杨倩
毕直磊
张鑫
杨文刚
LI QI;SHI Peng;YANG Qian;BI Zhilei;ZHANG Xin;YANG Wengang(Shaanxi Key Laboratory of Earth Surface System Environmental Carrying Capacity,College of Urban and Environmental Sciences,Northwest University,101277,Xi’an,Shaanxi,China;State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China,Xi’an University of Technology,710048,Xi’an,Shaanxi,ChinaBeijing Piesat Information Technology Co.,Ltd,100195,Beijing,China)
出处
《北京师范大学学报（自然科学版）》
CAS
CSCD
北大核心
2019年第1期153-159,共7页
Journal of Beijing Normal University(Natural Science)
基金
国家自然科学基金资助项目(41601092
51308457)
陕西省自然科学基金资助项目(2012JM7014)
中国博士后基金资助项目(2015M572591)
