文献类型：期刊文献

英文题名：Soil microbial biomass C:N:P stoichiometry is driven more by climate, soil properties and plant traits than by N enrichment in a desert steppe

作者：Fang, Zhao[1,2,3,4] Yu, Hailong[5] Li, Chunhuan[5] Wang, Bin[6] Huang, Juying[1,2,3]

第一作者：Fang, Zhao

通信作者：Huang, JY[1];Huang, JY[2];Huang, JY[3]

机构：[1]Breeding Base State Key Lab Land Degradat & Ecol, Yinchuan 750021, Ningxia, Peoples R China;[2]Minist Educ, Key Lab Restorat & Reconstruct Degraded Ecosyst N, Yinchuan 750021, Ningxia, Peoples R China;[3]Ningxia Univ, Sch Ecol & Environm, Yinchuan 750021, Ningxia, Peoples R China;[4]Northwest A&F Univ, Inst Soil & Water Conservat, Yangling 712100, Shaanxi, Peoples R China;[5]Ningxia Univ, Sch Geog & Planning, Yinchuan 750021, Ningxia, Peoples R China;[6]Chinese Acad Forestry, Res Inst Subtrop Forestry, Fuyang 311400, Peoples R China

年份：2022

卷号：216

外文期刊名：CATENA

收录：;Scopus(收录号：2-s2.0-85131129323);WOS:【SCI-EXPANDED(收录号:WOS:000832992600002)】；

基金：This work was financially supported by the Natural Science Foundation of Ningxia (2022AAC02012) and the National Natural Science Foundation of China (32160277 and 41961001). Special thanks to Weibo Kong and Zhilin Pei for their guidance and help in data analysis and graphing.

语种：英文

外文关键词：N enrichment; Microbial stoichiometry; Stoichiometric homeostasis; Desert steppe

摘要：The impacts of increased ecosystem nitrogen (N) inputs on soil microbial biomass C:N:P stoichiometry have been extensively explored. However, the stoichiometric homeostasis and driving mechanisms of microbial C:N:P stoichiometry following N enrichment remain elusive in dryland ecosystems, especially in moderately alkaline desert steppes. Here, we employed a five-year (2015-2019) N enrichment experiment to examine the changes in microbial C:N:P stoichiometry and the strength of stoichiometric homeostasis in a moderately alkaline desert steppe in northwest China. Climate factors, plant traits, and soil properties were analyzed to determine the critical factors influencing microbial C:N:P stoichiometry. The results showed that microbial C:N:P stoichiometry changed little under low doses of N input (<10 g m(-2) yr(-1)), and only microbial biomass C increased significantly by 35.89%-51.26% at 1.25 and 2.50 g m(-2) yr(-1). In contrast, a high N enrichment rate (20 g m(-)(2) yr(-1)) significantly enhanced the microbial biomass N (average 61.88%) and N:P (44.55%) but decreased the microbial biomass C:N (37.25%). However, microbial biomass P and C:P showed no significant changes under N enrichment. Significant interannual differences were observed in microbial C:N:P stoichiometry, whereas the effects of the interaction of N enrichment and year were not significant (except for microbial biomass C and C:P). With increasing N enrichment, microbes basically maintained strong elemental homeostasis. Moreover, we found that climate factors (explaining about 16% of the variation), soil properties (13%) and plant traits (4%) played critical roles in shaping microbial C:N:P stoichiometry. N enrichment represented only - 3% of the variation and thus had a weaker effect on microbial C:N:P stoichiometry. Altogether, our findings suggest that soil microbial C:N:P stoichiometry is more likely driven by climate factors, soil properties, and plant traits than by N enrichment in dryland ecosystems.