Nutrient limitation of soil organic carbon stocks under straw return

Straw return has been widely used to increase SOC storage globally, but such C accrual is frequently constrained by other nutrients which are needed to maintain soil ecological stoichiometry balance. However, the impact of fertilization on SOC stocks under straw return remains unexplored at broad spatial scales. We constructed a national-scale dataset to explore the fertilization effect on SOCstocks (0-20 cm) under straw return and identified the dominant drivers and pathways in upland and paddy systems across China.