基于森林景观斑块间耦合作用的加权网络构建

发布时间：2018-05-05 18:28

  本文选题：森林景观 + 网络　； 参考：《中南林业科技大学》2017年硕士论文

【摘要】：复杂生态网络是从系统角度,结合复杂网络技术,进行生态学现象研究的有效方法。项目组在之前的研究中,构建了无权森林景观斑块耦合网络,对森林景观斑块是否连接做了定性描述,但在实际的森林景观生态系统中,不同森林景观斑块间不停的进行物质、能量和信息的流动,斑块间存在着或强或弱的耦合作用,且斑块间的耦合作用强度对森林景观生态系统的性质有重要影响。本文强调森林景观斑块间的耦合作用,构建加权森林景观斑块耦合网络,更真实客观的抽象了复杂的森林景观生态系统。本文以西洞庭湖区为研究对象,对该区域的森林景观类型进行分类,基于物种多样性和土壤肥力对斑块间的耦合作用进行研究,以景观斑块为节点,斑块间的耦合作用为边权,构建加权森林景观斑块耦合网络,并对加权森林景观斑块耦合网络和无权网络的拓扑结构进行简要的分析和对比。主要研究内容和研究结论如下:(1)基于物种多样性的斑块间耦合作用研究。本文对不同森林景观斑块内物种多样性水平进行分析,采用熵权法和综合评价法计算物种多样性综合指数,全面量化了不同森林景观林下物种多样性水平,并对不同森林景观斑块间的耦合作用进行分析,结果表明:阔叶林与竹林间耦合作用最强,阔叶林与松木幼龄林间耦合作用最弱;从森林景观类型分析,阔叶林与其它森林景观斑块间的耦合作用具有阔竹阔灌阔松阔杉的规律;从不同龄组进行分析,在杉木和松木林中,森林景观斑块间耦合作用强度具有幼龄林与成熟林斑块间的耦合作用大于幼龄林与中龄林斑块间的耦合作用的规律,中龄林与成熟林间的耦合作用较小。(2)基于土壤肥力质量的斑块间耦合作用研究。本文对土壤的理化性质进行分析,采用主成分分析法计算不同森林景观内的土壤肥力质量指数,并对其耦合作用进行分析,结果表明:阔叶林与竹林间的耦合作用最强,杉木幼龄林与杉木中龄林间的耦合作用最弱;杉木与松木间的耦合作用在0-0.2之间,阔叶与其它森林景观斑块间的耦合作用在0.2-0.4范围内,竹林与其它森林景观斑块类型间的耦合作用在0.4-1.0范围内,林分类型是基于土壤肥力的森林景观斑块间的耦合作用大小的主要影响因子。(3)提出了以斑块间耦合作用为边权,构建加权森林景观斑块耦合网络的一种方法。本文选取15个森林景观斑块耦合体,以斑块为节点,分别以基于物种多样性和土壤肥力的斑块间耦合作用为边权,构建出30个加权森林景观斑块耦合网络。(4)对本文所构建的加权森林景观斑块耦合网络和无权森林景观斑块耦合网络的拓扑结构进行研究并对比分析,结果表明:加权和无权的森林景观斑块耦合网络的节点度分布符合幂律分布,具有无标度特性。基于物种多样性和土壤肥力质量构成的加权森林景观斑块耦合网络均具有小世界特性,且小世界特性与网络规模成正比;无权的森林景观斑块耦合网络的小世界特性不具有普适性;加权森林景观斑块耦合网络比无权森林景观斑块耦合网络小世界特性更显著,所以加权森林景观斑块耦合网络能更好的体现森林景观生态系统内物种、能量和信息的传播能力。
[Abstract]:Complex ecological network is an effective method to study ecological phenomena from the perspective of system, combined with complex network technology. In the previous study, the project group constructed the unauthorized forest landscape patch coupling network, and made a qualitative description of the connection of forest landscape patches, but in the actual forest landscape ecosystem, different forest landscape spots. There is a strong or weak coupling between the patches, and the coupling action between patches has an important influence on the nature of the forest landscape ecosystem. This paper emphasizes the coupling effect of the forest landscape patches, and constructs a weighted forest landscape patch coupling network, which is more realistic and objective. Like the complex forest landscape ecosystem, this paper takes the West Dongting Lake area as the research object, classifies the forest landscape types in this area, studies the coupling effect between the patches based on the species diversity and soil fertility, takes the landscape patch as the node, and the coupling action between the patches is the edge weight, and constructs the weighted forest landscape patch coupling. The network, and a brief analysis and comparison of the topology structure of the weighted forest landscape patch coupling network and the unauthorized network. The main research contents and research conclusions are as follows: (1) the study on the coupling interaction between patches based on species diversity. This paper analyses the species diversity in different forest landscape patches, uses entropy weight method and synthesis. The evaluation method calculated the diversity index of species diversity, comprehensively quantified the diversity of species diversity under different forest landscape, and analyzed the coupling effect of different forest landscape patches. The results showed that the coupling effect between broadleaf forest and bamboo forest was the strongest, and the coupling effect between broadleaf forest and young pine trees was the weakest; from forest landscape type, the forest landscape type was broadened. The coupling effect of leaf forest and other forest landscape patches has the law of broadleaved broadleaved latissimus latissimus. Analysis from different age groups, in Chinese fir and pine forest, the coupling effect between forest landscape patches has greater coupling effect between young and mature forest patches than between young and middle age forest patches. The coupling effect between the aged forest and the mature forest is small. (2) the coupling effect of soil fertility based on the soil fertility quality. In this paper, the physical and chemical properties of the soil are analyzed. The principal component analysis method is used to calculate the soil fertility quality index in different forest landscapes, and the coupling effect of the soil is analyzed. The results show that the coupling between the broadleaf forest and the bamboo forest is coupled. The coupling effect between the young Chinese fir forest and the middle age forest of Chinese fir is the weakest; the coupling effect between the Chinese fir and the pine trees is between 0-0.2, the coupling interaction between broadleaf and other forest landscape patches is within the range of 0.2-0.4. The coupling of bamboo forest and other forest landscape patch types is within the range of 0.4-1.0, and the forest type is based on the soil. The main influence factor of the coupling effect between the fertile forest landscape patches. (3) a method is proposed to construct a weighted forest landscape patch coupling network with the coupling action between patches. In this paper, 15 forest landscape patch coupling is selected to distinguish patches based on patches based on species diversity and soil fertility. 30 weighted forest landscape patch coupling networks are constructed by the coupling action. (4) the topological structure of the weighted forest landscape patch coupling network and the unauthorized forest landscape patch coupling network constructed in this paper is studied and compared. The results show that the node degree distribution of the weighted and unweighted forest landscape patch coupling network is based on the results. The weighted forest landscape patch coupling network based on species diversity and soil fertility quality has small world characteristics, and the small world characteristics are proportional to the network size; the small world specificity of the unweighted forest landscape patch coupling network is not universal; weighted forest landscape patch coupling The network is more prominent than the small world of the unauthorized forest landscape patch coupling network, so the weighted forest landscape patch coupling network can better reflect the species, energy and information transmission ability in the forest landscape ecosystem.

【学位授予单位】：中南林业科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S757
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本文编号：1848816