摘要
随着国家对生态环境的重视和水土保持科学的发展,有关土壤侵蚀危险性评价的研究越来越重要。本文对土壤侵蚀危险度评价的一般方法进行了改进。首先,分析了安溪县各强度等级的土壤侵蚀在高程、坡度、土地利用类型和土壤类型的面积分布情况,计算了不同高程带、不同坡度、不同土地利用类型和土壤类型的土壤侵蚀综合指数;然后,以各影响因子的土壤侵蚀综合指数为权重,计算了不同侵蚀影响因子在安溪县各子流域的土壤侵蚀危险度,既避免了权重确定的主观性,又保证了土壤侵蚀危险度的计算适合当地的实际情况,从而明确了各子流域土壤侵蚀发生的可能程度;最后,依据土壤侵蚀危险度和土壤侵蚀强度的分布规律,对整个研究区进行了水土保持分区,提出了治理方向。
Soil erosion risk assessment is crucial to soil and water conservation monitoring,harnessing and so on.With the increase of national attention on the ecological environment and the development of science of soil and water conservation,research of soil erosion risk assessment is becoming more and more important.By consulting the published researches on soil erosion risk assessment,an improved method of soil erosion risk assessment was adopted in this paper.Firstly,distribution of soil erosion degree by various impact factors including altitude,gradient,land use type and soil types were calculated by GIS and statistic analysis.Secondly,integrative index of different soil erosion degree by impact factors were computed.Then the soil erosion risks by different impact factors for every subbasin were calculated by weighting impact factors corresponding to each degree of integrative index of soil erosion.Thirdly,soil erosion risk by every impact factor was classified into three levels and the corresponding maps were finished.The integrative degree of soil erosion risk also was classified by cluster analysis.Finally,comparing distribution of different soil erosion intensity with the distribution of soil erosion risk,the studied area was regionalized with various soil and water conservation aims.The results were that：（1） the method was reasonable and suitable for actual conditions,and it avoided subjectivity in weight decision.（2） The relationship between soil erosion and impact factors in Anxi County,Fujian Province were discussed.The intensity of soil erosion in 500m altitude zone,3～15°gradient zone,dry land and other wood land,acid skeleton soil and acid stone soil was greater than other grades of corresponding impact factors.（3） According the spatial distribution of soil erosion risk,the possibility of erosion of every subbasin and different effect of impact factors were clearly showed.The distribution of soil erosion risk and intensity of soil erosion are basically in accordance.（4） By comparing c
出处
《地球信息科学》
CSCD
北大核心
2009年第5期577-584,共8页
Geo-information Science
基金
国家重点基础研究发展计划973项目(2007CB407207)
国家自然科学基金项目(40571095)
福建省自然科学基金项目(D0810008)
