贵州茂兰峰丛森林洼地泥沙堆积速率的^137Cs示踪研究  

Study on Sediment Accumulation Rate in Karst Peak-Cluster Forest Depression Catchment Using ^(137)Cs Method in the Maolan Area of Guizhou Province

作　　者：何永彬[1,2] 李豪[1,2] 张信宝[1,3] 白晓永[1,2] 严冬春[1,2] 文安邦[1] 冉景丞[4] 谭卫林[4] 

机构地区：[1]中国科学院、水利部成都山地灾害与环境研究所,成都610041 [2]中国科学院研究生院,北京100049 [3]中国科学院地球环境研究所黄土与第四纪地质国家重点实验室,西安710075 [4]贵州茂兰国家级自然保护区管理局,贵州荔波558400

出　　处：《地球与环境》2009年第4期366-372,共7页Earth and Environment

基　　金：国家重点基础研究发展计划项目(2006CB403203,2007CB407206);中国科学院知识创新工程项目(KZCX3-SW-448);中国科学院水土保持研究所国家重点实验室基金项目(10501-109)资助

摘　　要：选择黔南峰丛洼地区的茂兰自然保护区的坡格森林洼地典型小流域,进行了泥沙堆积的137Cs示踪研究。(1)坡格森林洼地底部的土壤剖面属于农耕地剖面。(2)受岩土分布、微地形和土壤异质性的影响,137Cs初始沉降后的再分布不均匀,137Cs面积活度变异系数为1.54。相同组成特征的地块内部样点137Cs面积活度变异系数变化为0.36～0.54,变异相对较小。但137Cs面积活度不能表征土壤侵蚀状况。(3)典型沉积剖面B-1的单一137Cs峰值浓度出现在14～16cm,高浓度137Cs均匀分布深度小于当地犁耕层厚度20cm,说明1963年以来坡格森林洼地的堆积速率接近于0。This study one typical forest depression of a peak-cluster area was selected as the study area in the Maolang nature reserve in southern Guizhou Province,and ^137Cs tracing research was conducted on sediment accumulation and water erosion.（1） The soil core profile was a cultivately disturbed profile.（2）Affected by earth-rock distribution,microtopography and soil heterogeneity,^137Cs redistribution after primary fallout was uneven,and ^137Cs inventories have a greater spatial variation coefficient of 1.54.And the section interior with the same composition showed smaller spatial variation in coefficient,ranging from 0.360.54.And it is shown that ^137Cs inventory in the soil section could not characterize the state of water erosion.（3） With reference to the ^137Cs depth distribution of typical profile B-1,the single ^137Cs peak value emerged at the depth of 14 cm to 16 cm in typical soil profile B-1,and higher ^137Cs concentrations in the soil profile are evenly distributed from 0cm to 16cm.The depth of higher ^137Cs even distribution was lower than the local ploughing depth （20 cm）,showing that the accumulation rate of sediment in the forest depression has been almost zero since 1963.

关 键 词：^137Cs含量 沉积剖面 森林洼地小流域 泥沙堆积速率 喀斯特峰丛洼地 茂兰 

分 类 号：P512.31[天文地球—地质学] S157[农业科学—土壤学]