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10 páginas.- 4 figuras.- 3 tablas.- referencias.- upplementary data to this article can be found online at https://doi. org/10.1016/j.apsoil.2023.104890, Forests are critical for supporting multiple ecosystem services such as climate change mitigation. Microbial diversity in soil provides important functions to maintain and regenerate forest ecosystems, and yet a critical knowledge gap remains in identifying the linkage between attributes of regenerated woody plant (RWP) communities and the diversity patterns of soil microbial communities in subtropical plantations. Here, we investigated the changes in soil microbial communities and plant traits in a nine hectare Chinese fir (Cunninghamia lanceolata; CF) plantation to assess how non-planted RWP communities regulate soil bacterial and fungal diversity, and further explore the potential mechanisms that structure their interaction. Our study revealed that soil bacterial richness was positively associated with RWP richness, whereas soil fungal richness was negatively associated with RWP basal area. Meanwhile, RWP richness was positively correlated with ectomycorrhizal (ECM) fungal richness but negatively correlated with the richness of both pathogenic and saprotrophic fungi, suggesting that the RWP-fungal richness relationship was trophic guild-specific. Soil microbial community beta diversity (i.e., dissimilarity in community composition) was strongly coupled with both RWP beta diversity and the heterogeneity of RWP basal area. Our study highlights the importance of community-level RWP plant attributes for the regulation of microbial biodiversity in plantation systems, which should be considered in forest management programs in the future., This work was funded by the National Key Research and Development Program of China (2021YFD2201301 and 2022YFF1303003), the National Natural Science Foundation of China (U22A20612), and the Key Project of Jiangxi Province Natural Science Foundation of China (20224ACB205003).

树干表面CO2通量是森林生态系统碳收支的重要组成部分，对全球碳平衡产生重要影响。近年来，全球变化导致植物光合产物供应发生改变，这将影响树干表面CO2通量。然而，关于光合产物供应如何影响树干表面CO2通量的机理仍不清楚。以盆栽杉木（Cunninghamia lanceolata）幼苗为研究对象，采用遮光方法减少光合产物供应，通过自制呼吸气室，使用Li-8100测定树干表面CO2通量，并结合树干可溶性糖、淀粉和非结构性碳及树干温度等数据分析遮光对树干表面CO2通量的影响。结果表明：遮光后树干可溶性糖、淀粉和非结构性碳含量分别显著下降了55.0%、78.9%和64.3%。遮光处理阶段树干表面CO2通量平均下降39.9%，且下降幅度随着遮光时间的延长而增加；此外，遮光降低了树干表面CO2通量的温度敏感性。恢复光照后，树干表面CO2通量、树干可溶性糖、淀粉和非结构性碳含量以及树干温度均恢复至对照水平。可见，光合产物供应变化对树干表面CO2通量具有调控作用，而且能够通过调控树干表面CO2通量对温度变化的响应对全球碳循环产生重要影响。