Modified Method for Estimating Organic Carbon Density in Discontinuous Karst Soil Using Ground-Penetrating Radar and Geostatistics  

作　　者：LI Lei XIA Yin-hang LIU Shu-juan ZHANG Wei CHEN Xiang-bi ZHENG Hua QIU Hu-sen HE Xun-yang SU Yi-rong 

机构地区：[1]Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences [2]Huanjiang Observation and Research Station for Karst Eco-systems [3]University of Chinese Academy of sciences [4]Guangxi Institute of Subtropical Crops

出　　处：《Journal of Mountain Science》2015年第5期1229-1240,共12页山地科学学报（英文）

基　　金：supported by National Science and Technology Support Project (Grant No. 2012BAD05B03–6);Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA05070403);National Natural Science Foundationof China (Grant No. 41171246)

摘　　要：The conventional method which assumes the soil distribution is continuous was unsuitable for estimating soil organic carbon density(SOCD) in Karst areas because of its discontinuous soil distribution. The accurate estimation of SOCD in Karst areas is essential for carbon sequestration assessment in China. In this study, a modified method,which considers the vertical proportion of soil area in the profile when calculating the SOCD, was developed to estimate the SOCD in a typical Karst peak-cluster depression area in southwest China. In the modified method, ground-penetrating radar(GPR) technology was used to detect the distribution and thickness of soil. The accuracy of the method was confirmed through comparison with the data obtained using a validation method, in which the soil thickness was measured by excavation. In comparison with the conventional method and average-soil-depth method,the SOCD estimated using the GPR method showed the minimum relative error with respect to that obtained using the validation method. At a regional scale, the average SOCDs at depths of 0-20 cm and 0-100 cm, which were interpolated by ordinary kriging,were 1.49(ranging from 0.03-5.65) and 2.26(0.09-11.60) kgm-2based on GPR method in our study area(covering 393.6 hm2), respectively. Therefore, the modified method can be applied on the accurate estimation of SOCD in discontinuous soil areas such as Karst regions.

关 键 词：Discontinuous soil Organic carbondensity Soil distribution Estimation method Ground penetrating radar KARST Peak clusterdepression 

分 类 号：P642.25[天文地球—工程地质学] P631.3[天文地球—地质矿产勘探]