An empirical approach to predict regional organic carbon in deep soils  

作　　者：Jingjing WANG Xiaorong WEI Xiaoxu JIA Mingbin HUANG Zhipeng LIU Yufei YAO Ming’an SHAO 

机构地区：[1]State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Northwest A&F University,Yangling 712100,China [2]Institute of Soil and Water Conservation,Ministry of Water Resources and Chinese Academy of Sciences,Yangling 712100,China [3]CAS Center for Excellence in Quaternary Science and Global Change,Xi’an 710061,China [4]Key Laboratory of Ecosystem Network Observation and Modeling,Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China [5]College of Resources and Environmental Sciences,Nanjing Agricultural University,Nanjing 210095,China [6]College of Urban and Environmental Sciences,Northwest University,Xi’an 710127,China

出　　处：《Science China Earth Sciences》2023年第3期583-593,共11页中国科学（地球科学英文版）

基　　金：supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant Nos.XDA23070202 and XDB40020000);the National Key Research and Development Program(Grant No.2022YFF1302804);the National Natural Science Foundation of China(Grant Nos.41977068 and 41622105);the Program from Chinese Academy of Sciences(Grant No.QYZDB-SSWDQC039)。

摘　　要：Deep soil organic carbon(SOC)plays an important role in carbon cycling.Precisely predicting deep SOC at the regional scale is crucial for the accurate assessment of carbon sequestration potential in soils but has been challenging for a century.Herein,we developed a depth distribution function-based empirical approach to predict SOC in deep soils at the regional scale.We validated this approach with a dataset from four regions of the world and examined the application of this approach in China’s Loess Plateau.We found that among the reported depth distribution functions describing vertical patterns of SOC,the negative exponential function performed best in fitting SOC along the soil profile in various regions.Moreover,the parameters(i.e.,Ceand k)of the negative exponential function were linearly correlated to surface SOC(0–20 cm)and the changing rates of SOC within the topsoil(0–40 cm).Based on the above relationships,the empirical equations for predicting the negative exponential parameters are established.The validation results from site-specific and regional dataset showed that combining the negative exponential function and such empirical equations can precisely predict SOC concentration in soils down to 500 cm depth.Our study provides a simple,rapid and accurate method for predicting deep soil SOC at the regional scale,which could simplify the assessment of deep soil SOC in various regions.

关 键 词：Deep SOC Empirical approach Negative exponential function Depth distribution Spatial pattern 

分 类 号：S153.6[农业科学—土壤学]