文献类型：期刊文献

英文题名：Forest Litter Chemical Traits and Microbial Stoichiometry Regulate the Formation and Stabilization of Soil Organic Matter

作者：Cheng, Xiangrong[1] Xing, Wenli[1] Liu, Jiangwei[1,2]

第一作者：成向荣

机构：[1] East China Coastal Forest Ecosystem Long-term Research Station, Institute of Subtropical Forestry, Chinese Academy of Forestry, Zhejiang, Hangzhou, 311400, China; [2] College of Forestry, Northwest Agriculture and Forestry University, Shaanxi, Yangling, 712100, China

年份：2022

外文期刊名：SSRN

收录：EI(收录号：20220319574)

语种：英文

外文关键词：Biogeochemistry - Cotton - Enzymes - Forestry - Mixtures - Particles (particulate matter) - Plants (botany) - Soils - Stoichiometry - Textures

摘要：Plant litter quality has a large impact on microbial activity and affects the decomposition and formation of soil organic matter (SOM). However, the influence of litter chemical traits and microbial stoichiometry on the SOM formation and stabilization pathways remains unclear. Herein, we conducted a 150-d incubation experiment using coastal coarse-textured Gleyic Cambisol with forest litter (poplar [Populus deltoides] leaves and roots, grasses grown under the poplar canopy, and a mixture of these three litter types). The particulate organic matter (POM) and mineral-associated organic matter (MAOM) fractions of the soil and stoichiometric ratios (C:N:P) for microbial biomass and enzymes were analyzed 50, 100, and 150 d after the initial addition of the litter. Both the production and contribution of the microbial residues (amino sugar biomarkers) to the SOM were also measured at the end of decomposition. We found that the leaf litter with a higher N concentration and lower lignin:N ratio favored the MAOM accumulation compared with root and grass litter. Furthermore, compared with single litter additions, the litter mixture contributed more C to the POM fraction, and thus led to more C accrual in the SOM. Moreover, the C concentrations in the POM and MAOM fractions were strongly regulated by the microbial carbon use efficiency and enzyme stoichiometry during litter decomposition. The leaf litter produced more microbial residue C in the MAOM than the root and grass litter, while the contribution to the MAOM-C was lower than that of the latter, and the opposite pattern was observed for the POM. The proportion of microbial residue C in the litter-addition treatments accounted for 6-19% of the total C in the SOM, suggesting that the microbial assimilation pathway was not the dominant driver of SOM stabilization in coastal coarse-textured soil. These findings highlight that different litter chemical traits or litter types may alter the SOM formation and stabilization pathways, and that microbial stoichiometry regulates this process. ? 2022, The Authors. All rights reserved.