Changes in microbial composition explain the contrasting responses of glucose and lignin decomposition to soil acidification in an alpine grassland

Fuwei Wang; Yue Gao; Xin Li; Mengdi Luan; Xiaoyi Wang; Yanwen Zhao; Xianhui Zhou; Guozhen Du; Peng Wang; Chenglong Ye; Hui Guo

doi:10.1016/j.scitotenv.2024.172671

Changes in microbial composition explain the contrasting responses of glucose and lignin decomposition to soil acidification in an alpine grassland

Sci Total Environ. 2024 Apr 21:930:172671. doi: 10.1016/j.scitotenv.2024.172671. Online ahead of print.

Authors

Fuwei Wang¹, Yue Gao², Xin Li², Mengdi Luan², Xiaoyi Wang², Yanwen Zhao², Xianhui Zhou³, Guozhen Du³, Peng Wang², Chenglong Ye⁴, Hui Guo⁵

Affiliations

¹ Ecosystem Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China; College of Resource and Environment, Anhui Science and Technology University, Fengyang 233100, China.
² Ecosystem Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China.
³ State Key Laboratory of Grassland and Agro-ecosystems, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
⁴ Ecosystem Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: chenglongye@njau.edu.cn.
⁵ Ecosystem Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: hui.guo@njau.edu.cn.

PMID: 38653407
DOI: 10.1016/j.scitotenv.2024.172671

Abstract

Soil acidification often suppresses microbial growth and activities, resulting in a negative impact on soil organic carbon (C) decomposition. While the detrimental effects of acidification on soil and plant properties have been extensively studied, less attention has been paid on the shifts in soil microbial communities and their influences of the decomposition of organic C with different chemical complexities. Taking advantage of an acid addition experiment in a Tibetan alpine meadow, here we examined the response of soil microbial communities to soil acidification and microbial effect on the decomposition of organic C with different chemical complexities (i.e., glucose and lignin, representing labile and recalcitrant C respectively). We found that soil acidification had no impact on microbial respiration and microbial abundance even though it decreased bacterial diversity significantly. Soil acidification increased the relative abundance of some microbial taxa, like Alphaproteobacteria and Acidobacteriia in bacteria increased by 36 %, 284 %, and Eurotiomycetes, Sordariomycetes and Leotiomycetes in fungi increased by 145 %, 279 % and 12.7-fold, but decreased the relative abundance of Acidimicrobiia by 33 % in highest acid addition treatment. Changes in microbial communities (bacterial and fungal community composition, the diversity of bacterial community and the ratio of fungi to bacteria) are significantly related to the decomposition of glucose and lignin. More specifically, soil acidification decreased the decomposition of glucose but increased the decomposition of lignin, indicating a trade-off between the decomposition of labile and recalcitrant soil organic C under soil acidification. Overall, shifts in microbial communities under soil acidification might be accompanied by an increased ability to break down more recalcitrant C. This trade-off between the decomposition of labile and recalcitrant C may change soil C quality under future acid deposition scenarios.

Keywords: Alpine grassland; C decomposition; Microbial composition; Soil acidification.