| 论文标题： | |
|---|---|
| 作者： | |
| 出版刊物： | |
| 出版日期： | |
| 出版年份： | |
| 卷/期： | |
| DOI： | |
| 论文摘要： | Global nitrogen (N) deposition and precipitation change are two important factors influencing the diversity and function of terrestrial ecosystems. While considerable efforts have been devoted to investigate the responses of aboveground plant communities to altered precipitation regimes and N enrichment, the variations of belowground soil microbial communities are not well understood, particularly at the functional gene structure level. Based on a 9-year field experiment established in a typical steppe in Inner Mongolia, China, we examined the impacts of projected N deposition and precipitation increment on soil microbial functional gene composition, and assessed the soil/plant factors associated with the observed impacts. The overall functional gene composition significantly shifted in response to precipitation increment, N deposition and their combinations (all ADONIS P < 0.05), and such changes were primarily correlated with soil pH, microbial biomass, and microbial respiration. Water supply increased the abundances of both carbon (C) and N cycling genes, suggesting that the projected precipitation increment could accelerate nutrient cycling in this semi-arid region. N effects were mainly observed on the genes involved in vanillin/lignin degradations, implying that the recalcitrant C would not accumulate in soil under future scenarios of higher N deposition. Structural equation modeling (SEM) analysis revealed that soil dissolved organic carbon (DOC) was a key factor directly determining the abundance of C degradation and N cycling genes, and aboveground plant biomass indirectly influenced gene abundance through enhancing DOC. The present work provides important insights on the microbial functional feedbacks to projected global change in this semi-arid grassland ecosystem, and the mechanisms governing C and N cycles at the regional scale. (C) 2016 Elsevier Ltd. All rights reserved. |
以下内容与「星空体育彩票与多特蒙德续约官方合作」同属公开资讯，可按栏目接着查阅相关条目。
本站按公开材料组织页面。需要原文时请核对应栏目发布页。
若从搜索引擎进入，可先确认当前栏目名称，再按需打开相关阅读。
