文献类型：期刊文献

英文题名：Soil and microbial stoichiometry shape microbial necromass carbon accrual in topsoil and subsoil across tree species diversity

作者：Zhang, Yulin[1] Hao, Zongran[1] Cheng, Xiangrong[1,2]

通信作者：Cheng, XR[1]

机构：[1]Chinese Acad Forestry, Res Inst Subtrop Forestry, East China Coastal Forest Ecosyst Res Stn, Hangzhou 311400, Zhejiang, Peoples R China;[2]Chinese Acad Forestry, State Key Lab Wetland Conservat & Restorat, Beijing 100091, Peoples R China

年份：2026

卷号：219

外文期刊名：APPLIED SOIL ECOLOGY

收录：;Scopus(收录号：2-s2.0-105026974010);WOS:【SCI-EXPANDED(收录号:WOS:001663315600002)】；

基金：This study was supported by the Science Research Project of Baishanzu National Park (Grant No. 2021KFLY02) , National Natural Science Foundation of China (Grant No. 32271855) , and the Zhejiang Province and Chinese Academy of Forestry Collaborative Project (Grant No. 2025SY05) . We would like to thank Editage ( www.editage.cn) for English language editing and Baihui Biotechnology Co. Ltd., Chengdu ( www.baihuitech.cn) for the soil phospholipid fatty acids and amino sugar measurements.

语种：英文

外文关键词：Tree species diversity; Microbial necromass carbon; Elemental stoichiometry; Soil organic carbon

摘要：Changes in soil and microbial elemental stoichiometry regulate microbial metabolic processes, thereby influencing soil microbial necromass carbon (C) accumulation in forest ecosystems. Tree species diversity can influence soil and microbial elemental stoichiometry by modifying the litter properties and nutrients availability. However, how stoichiometric changes regulate microbial necromass C accrual across soil profiles along diversity gradients remains unclear. We investigated bacterial and fungal microbial necromass C fractions and their contributions to soil organic carbon (SOC) and C:nitrogen (N):phosphorus (P) stoichiometry in bulk soil, microbial biomass, and extracellular enzymes. We also assessed microbial traits (e.g., biomass and C-use efficiency) in the topsoil (0-10 cm) and subsoil (40-50 cm) along a tree species diversity gradient in subtropical forests. We found that increasing tree species diversity significantly enhanced microbial necromass C content and its contributions to SOC in the topsoil, but had little effect on the subsoil. In the topsoil, tree species diversity altered available soil nutrient, microbial biomass, and enzymatic stoichiometry. The increased accumulation of microbial necromass C was mainly driven by increased microbial biomass, facilitated by higher microbial C-use efficiency and improved nutrient availability. In contrast, in the subsoil, increased total soil nutrients and microbial biomass C:P ratios along tree species diversity gradients enhanced microbial biomass, but were not significantly associated with microbial necromass C production. The limited variation in subsoil microbial necromass C may be attributable to the microbial recycle of necromass under low nutrient conditions (e.g., limited P). Overall, our findings demonstrate that the effect of tree species diversity on microbial necromass C accrual is depth-dependent, mediated by shifts in microbial elemental demands through altered substrate availability and enzymatic investment strategies. This stoichiometric framework provides new insights into how tree diversity shapes microbial necromass C dynamics across soil profiles in forest ecosystems.