A review on digital mapping of soil carbon in cropland: progress, challenge, and prospect

作者：Haili Huang, Lin Yang, Lei Zhang, Yue Pu, Chenconghai Yang, Qi Wu, Yanyan Cai, Feixue Shen, Chenghu Zhou · 发表于：Environmental Research Letters · 年份：2022 · DOI：10.1088/1748-9326/aca41e · 被引用次数：67 · 研究领域：Soil Geostatistics and Mapping、Soil Carbon and Nitrogen Dynamics、Soil erosion and sediment transport

Abstract Cropland soil carbon not only serves food security but also contributes to the stability of the terrestrial ecosystem carbon pool due to the strong interconnection with atmospheric carbon dioxide. Therefore, the better monitoring of soil carbon in cropland is helpful for carbon sequestration and sustainable soil management. However, severe anthropogenic disturbance in cropland mainly in gentle terrain creates uncertainty in obtaining accurate soil information with limited sample data. Within the past 20 years, digital soil mapping has been recognized as a promising technology in mapping soil carbon. Herein, to advance existing knowledge and highlight new directions, the article reviews the research on mapping soil carbon in cropland from 2005 to 2021. There is a significant shift from linear statistical models to machine learning models because nonlinear models may be more efficient in explaining the complex soil-environment relationship. Climate covariates and parent material play an important role in soil carbon on the regional scale, while on a local scale, the variability of soil carbon often depends on topography, agricultural management, and soil properties. Recently, several kinds of agricultural covariates have been explored in mapping soil carbon based on survey or remote sensing technique, while, obtaining agricultural covariates with high resolution remains a challenge. Based on the review, we concluded several challenges in three categories: sampling, agr...