| 甘南亚高山草甸弃耕演替过程中植物群落特征变化模式研究 |
| Alternative Title | A study on the pattern of plant community characters change during the succession in abandoned croplands of sub-meadow
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| 宋晓谕 |
| Thesis Advisor | 王刚
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| 2010-05-30
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| Degree Grantor | 兰州大学
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| Place of Conferral | 兰州
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| Degree Name | 硕士
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| Keyword | 亚高山草甸
弃耕地演替
物种多样性-生产力关系
物种-多度分布模式
植物群落氮磷比
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| Abstract | 本文通过采用空间代替时间的方法，对甘南亚高山草甸退耕时间为5年、9年、14年、19年、30年以及顶极群落样地进行调查、分析，以期探讨亚高山草甸弃耕地演替过程中植物群落特征的变化趋势及其机制，为甘南亚高山草甸地区草场恢复与生态保护提供理论依据。
研究结果表明：
1)在弃耕演替过程中，植物群落中的物种组成呈现出由简单向复杂发展的过程。演替初期植物群落内物种数较少，主要以一年生杂类草为主；演替中、后期植物群落中物种数明显增多，禾本科和豆科植物所占比例明显增加；从植物繁殖特征方面分析，随着演替时间的不断推移，植物群落中克隆繁殖的植物所占的比例逐渐增加，顶极群落中所占比例最大。
2）弃耕地演替过程中，随着演替时间的推移植物物种多样性指数先升后降，呈现单峰曲线，多样性指数最大值出现在演替时间为19年的样方中；生产力的变化趋势为前期迅速升高，之后生产力基本保持稳定，生产力最大值同样出现在演替时间为19年的样方中，达到183.77g/㎡。在弃耕演替过程中物种多样性与生产力呈现正相关关系，但当植物群落发展到顶极时物种多样性与生产力之间无明显的相关关系；
3）演替过程中群落中物种-多度分布模式由几何级数型分布逐渐向对数正态分布过渡； |
| Other Abstract | There were 5 year, 9 year, 14year, 19year, 30year abandoned croplands and climax plant communities. According to the succession gradient, we surveyed the changing characters of plant community to analysis the change model of the succession process, and to explore the reason which lead to those shifting characters. We hope that we could provide a theoretical basis to sub-alpine meadow restoration and protection.
The results showed:
1) During the succession, the plant community changed from simple to complex. In early stage forbs are the mainly group，then grasses and legumes take a large proportion in middle and upper stages. A significant increase in the proportion of clonal plants were shown during the succession and reached the peak in the climax plant community.
2) The biodiversity showed a unimodal curve, indicating the number of species increased first and decreased later along the succession gradient. In the early stage of succession, productivity enhanced rapidly and reached the highest with the mean of 183.77g/㎡ in the 19years-plots, and it then kept in a stable level. In the process of succession, biodiversity was positively related to productivity, although such a relationship disappeared in the climax community;
3) As the succession proceeded, the community pattern was gradually changed into a species log-normal distribution from the early niche-preemption； |
| URL | 查看原文
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| Language | 中文
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| Document Type | 学位论文
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| Identifier | https://ir.lzu.edu.cn/handle/262010/221458
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| Collection | 生命科学学院
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Recommended Citation
GB/T 7714 |
宋晓谕. 甘南亚高山草甸弃耕演替过程中植物群落特征变化模式研究[D]. 兰州. 兰州大学,2010.
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