| 生境过滤驱动庞泉沟华北落叶松林土壤真菌群落的构建过程 |
| 摘要点击 2072 全文点击 759 投稿时间：2017-12-19 修订日期：2018-02-27 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 确定过程 随机过程 群落构建 真菌群落 零模型 |
| 英文关键词 deterministic process stochastic process community assembly fungi community null model |
|
| 中文摘要 |
| 随机过程和确定过程的权衡作用对群落构建的影响机制是群落生态学研究的中心议题，也是目前群落生态学最具争议的问题.本研究以关帝山庞泉沟自然保护区华北落叶松林土壤真菌群落为研究对象，探讨确定过程和随机过程的权衡作用在局域尺度对土壤真菌群落构建的影响机制.通过土壤理化因子和优势真菌门的相关分析、冗余分析以及结构方程模型分析，表明土壤理化因子和地上植被多样性对真菌群落结构有显著影响，并且林下植被多样性对真菌群落结构的直接影响最大（1.1858）.由此推断确定过程对真菌群落的构建有一定的影响.真菌群落的β多样性表现为距离衰减的生物地理分布格局，由此推断随机过程（扩散限制）对真菌群落的构建有一定的影响作用.通过构建零模型分析，表明确定过程对真菌群落演替的贡献远大于随机过程，是本研究区真菌群落构建的主要驱动因子.并且确定过程的相对重要性随着海拔梯度而动态变化.由于零偏差值在本研究区都为负值，观测值的相似性小于期望值的相似性，由此推断生境过滤是群落构建的驱动因子.综上，确定过程和随机过程的权衡作用驱动了本研究区真菌群落的构建过程，且确定过程起主导作用. |
| 英文摘要 |
| The community assembly process, which purports that the trade-off between the stochastic process and the deterministic process, is the central issue of community ecology, and is one of the most controversial ecological issues. The current research investigated the fungal community in the Larix principis-rupprechtii forests of the Guandi Mountains and elucidated the relative role of the stochastic and deterministic processes in the assembly of soil fungal community on a local scale. The correlation analysis and redundancy analysis of the physicochemical factors in soil and dominant fungal phyla, as well as the structural equation model analysis, showed that these physicochemical factors and aboveground vegetation diversity had significant effects on fungal communities. The direct effect of vegetation diversity on fungal community structure was the most (1.1858). It is inferred that the determination process (environmental selection) has a certain influence on the assembly of fungal communities. The β-diversity of fungal community shows a distance-decay pattern; thus, it can be concluded that the stochastic process (dispersal limitation) has a certain effect on the assembly of fungal communities. Null model analysis confirmed that the deterministic process was the main driving factor for the assembly of the fungal communities in the study area, and their relative importance varied along with altitudinal gradient. The null deviations in the study area were negative, suggesting that habitat filtering was the driving factor of the assembly of fungal communities. Overall, the deterministic versus stochastic processes jointly drive the assembly of fungal communities in the study area, while the deterministic processes triumph. |
