A systematic and critical review of long-term diachronic experiments on soil organic carbon dynamics in the Global South

Unofficial AI-generated summary based on the public title and abstract. Not an official translation.

🔬研究者:Provides a comprehensive map of existing long-term SOC experiments in the Global South and identifies critical knowledge gaps for future research.

🏛政策担当者:Highlights the need for investment in long-term soil carbon monitoring in underrepresented regions to improve national greenhouse gas inventories.

Soil organic carbon (SOC) sequestration is increasingly recognized as a key lever for mitigating greenhouse gas emissions. However, knowledge about SOC dynamics under various land management practices remains limited in the Global South. Long-term experiments (LTEs), combined with a diachronic soil sampling approach, i.e., based on repeated measurements over time, offer robust insights into how land use and management practices affect SOC sequestration and provide indispensable observations for reliable model calibration. This systematic review compiles 155 peer-reviewed diachronic studies conducted in the Global South, excluding China, corresponding to 174 LTEs lasting at least 5 years. Most LTEs are conducted on cropland (92%), while agroforestry, forest, and savannah are underrepresented. The most frequently studied practices are mineral fertilization (52%), mixed mineral and organic fertilization (37%) and tillage management (30%). The effects of these practices on SOC dynamics show trends similar to those observed in the Global North, i.e., positive effects of both mineral and organic fertilization and conservation tillage. However, these findings may be biased by limited geographical, pedoclimatic, and agricultural practices representativeness . Arid soils and dry climates are underrepresented in favor of subhumid and humid areas. India and Brazil alone account for two-thirds of LTEs studies, despite their contrasting farming systems, smallholder agriculture in India versus large-scale mechanized systems in Brazil. This hides the variability of farming systems in the Global South. In many African and Southeast Asian countries, mineral fertilizer rates applied in LTEs exceed national averages by 100 to 1000%, while low-input traditional systems, such as agroforestry or slash-and-burn are absent. These imbalances reflect a funding and publication dynamic that favors agricultural systems and practices that are already well documented. These biases also present major blind spots for SOC modeling and limit the applicability of current knowledge to diverse farming systems in the Global South. It is therefore essential to intensify and diversify LTEs research to better reflect local practices and underrepresented pedoclimatic conditions.

• openalex https://doi.org/10.1016/j.geodrs.2026.e01101first seen 2026-07-02 05:10:18