Structural diversity enhances the temporal effects of thinning on carbon storage in pine-oak mixed forests

As a key silvicultural practice, thinning affects carbon storage dynamics, but the role of structural complexity, species composition, and functional traits in post-thinning recovery remains unclear. In this study, effects of structural, species, and plant trait diversity on ecosystem carbon storage (including live trees, litter, and soil) with post-thinning recovery were examined for pine-oak mixed forests in Qinling Mountains, China. We found that total carbon storage declined initially (4-year; 112.32 ± 8.51 Mg⋅ha^-1) but recovered to pre-thinning levels (131.70 ± 10.34 Mg⋅ha^-1 vs. 134.81 ± 9.40 Mg⋅ha^-1) by 12-year. A similar trend was observed in non-spatial structural diversity (Gini coefficient of DBH), emerging as the primary mechanistic driver of carbon storage changes during recovery, which was account for up to 68 % of the variance. The variation of spatial structure (Mingling, size dominance, and uniform angle index) showed no significant influence on carbon storage. Our findings highlight managing forests for structural complexity could enhance carbon sequestration in the context of global change.