Recently, the Agro-meteorological Disaster Prevention and Control Team at the Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, revealed for the first time the spatial differentiation pattern and driving mechanism of "increase in the north and decrease in the east" in soil organic carbon pools in China's semi-arid farmland. These findings provide a theoretical basis and technical support for carbon sequestration and emission reduction in agriculture. The related research was published in Communications Earth & Environment.

Soil organic carbon (SOC) is the largest terrestrial organic carbon pool on Earth, accounting for approximately 2,010 petagrams (Pg) of carbon, and it profoundly influences both carbon neutrality and food security. China's dryland covers over half of the country's total cultivated land, representing a region with huge carbon sequestration potential. However, it is also subject to multiple constraints, including climate warming, insufficient precipitation, and low soil fertility.

The research found that the northern dry farming region achieved a 14% increase in carbon sinks (with a cumulative carbon sequestration of 3.1 tons per hectare) through intensive agricultural management, equivalent to offsetting 1.5% of the national annual carbon emissions. In contrast, the northwestern region maintained a dynamic balance. The research established, for the first time, a carbon input threshold of 270 kg per hectare for straw returning - surpassing this critical point can effectively reverse the negative effects of climate warming. It also revealed that optimizing nitrogen fertilizer application boosted maize and wheat yields by 85%-151%, driving the formation of a "carbon-nitrogen synergistic sequestration" cycle. Furthermore, the application of organic fertilizer can further enhance carbon sequestration efficiency by more than 20%. This research not only provides key technical support for the Implementation Plan for Emission Reduction and Carbon Sequestration in Agriculture and Rural Areas, but also quantifies globally, for the first time, the implementation paths for carbon neutrality in dryland agriculture, contributing to safeguarding food security and achieving the 2060 carbon neutrality goal.

This research was supported by the National Key Research and Development Program and other projects.

Linkage: https://www.nature.com/articles/s43247-025-02754-8