The centennial legacy of land‐use change on organic carbon stocks of German agricultural soils

作者：David Emde, Christopher Poeplau, Axel Don, Stefan Heilek, Florian Schneider · 发表于：Global Change Biology · 年份：2024 · DOI：10.1111/gcb.17444 · 被引用次数：26 · 研究领域：Soil Carbon and Nitrogen Dynamics、Conservation, Biodiversity, and Resource Management、Rangeland Management and Livestock Ecology

Abstract Converting natural vegetation for agriculture has resulted in the loss of approximately 5% of the current global terrestrial soil organic carbon (SOC) stock to the atmosphere. Increasing the agricultural area under grassland may reverse some of these losses, but the effectiveness of such a strategy is limited by how quickly SOC recovers after conversion from cropland. Using soil data and extensive land‐use histories gathered during the national German agricultural soil inventory, this study aims to answer three questions regarding agricultural land‐use change (LUC): (i) how do SOC stocks change with depth following LUC; (ii) how long does it take to reach SOC equilibrium after LUC; and (iii) what is the legacy effect of historic LUC on present day SOC dynamics? By using a novel approach that substitutes space for time and accounts for differences in site properties using propensity score balancing, we determined that sites that were converted from cropland to grassland reached a SOC equilibrium level 47.3% (95% confidence interval (CI): 43.4% to 49.5%) above permanent cropland levels 83 years (95% CI: 79 to 90 years) after conversion. Meanwhile, sites converted from grassland to cropland reached a SOC equilibrium level −33.6% (95% CI: −34.1% to −33.5%) below permanent grassland levels after 180 years (95% CI: 151 to 223 years). We estimate that, over the past century, today's German agricultural soils (16.6 million ha) have gained about 40 million Mg C. Furthermore, ...