National variability in soil organic carbon stock predictions:Impact of bulk density pedotransfer functions  

作　　者：May-Thi Tuyet Do Linh Nguyen Van Xuan-Hien Le Giang V.Nguyen Minho Yeon Giha Lee 

机构地区：[1]Department of Advanced Science and Technology Convergence,Kyungpook National University,2559 Gyeongsang-daero,Sangju-si,37224,South Korea [2]Disaster Prevention Emergency Management Institute,Kyungpook National University,2559 Gyeongsang-daero,Sangju-si,37224,South Korea [3]Thuyloi University,175 Tay Son,Dong Da,Hanoi,10000,Viet Nam

出　　处：《International Soil and Water Conservation Research》2024年第4期868-884,共17页国际水土保持研究(英文)

基　　金：supported by Korea Environmental Industry&Technology Institute(KEITI)through R&D Program for Innovative Flood Protection Technologies against Climate Crisis Project,funded by Korea Ministry of Environment(MOE)[2022003460002].

摘　　要：Accurate soil organic carbon storage(SOCS)estimation is crucial for sustaining ecosystem health and mitigating climate change impacts.This study investigated the accuracy and variability of SOCS predictions,focusing on the role of pedotransfer functions(PTFs)in estimating soil bulk density(BD).Utilizing a comprehensive dataset from the Korean Rural Development Administration(RDA database),which includes 516 soil horizons,we evaluated 36 widely-used BD PTFs,well-established formulas that estimate BD by considering soil properties,including soil organic carbon(SOC),soil organic matter(OM),sand,gravel,silt,and clay.These PTFs demonstrated varying levels of precision,with root mean squared errors(RMSE)ranging from 0.177 to 0.377 Mg m^(-3) and coefficients of determination(R^(2))from 0.176 to 0.658;hence,the PTFs have been classified into excellent,moderate,and poor-performing groups for predicting BD.Further,a novel PTF based on an exponential function of SOC was developed,showing superior predictive power(R^(2)=0.73)compared to existing PTFs,using an independent validation dataset.Our findings reveal significant differences in SOCS predictions and observations among the PTFs,with a p-value<0.05.The highest concentrations of SOCS were noted in forest soils,considerably above the national average,highlighting the importance of tailored soil management practices to enhance carbon sequestration.These findings are crucial for refining PTF precision to improve the accuracy of national SOCS estimates,supporting effective land management and climate change mitigation strategies.

关 键 词：RDA database Soil organic carbon stock prediction Pedotransfer function Bayesian model average Regression method 

分 类 号：S15[农业科学—土壤学]