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Gap Dynamics and Forest Biodiversity in Mid-subtropical Evergreen Broad-leaved Forest of Fujian Province

Author: ZuoShuJun
Tutor: HongWei
School: Fujian Agriculture and Forestry University
Course: Ecology
Keywords: Gaps Subtropical evergreen broad-leaved forest Biodiversity
CLC: S718
Type: Master's thesis
Year: 2002
Downloads: 207
Quote: 8
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Abstract

Gaps are long-term changes in forest ecosystems essential elements, which constitute the formation and change the flow of forest landscape mosaic structure of the research gaps not only has important theoretical significance, but also has important practical value. Based on Wanmulin subtropical evergreen broad-leaved forest survey of 96 gaps studied subtropical evergreen broad-leaved forest of the basic characteristics and natural disturbance regime. The results show that, in the subtropical evergreen broad-leaved forest, expanded gap (EG) and canopy gaps (CG) in the subtropical evergreen broad-leaved forest landscape area ratio were 50.86% and 16.66%, respectively, 0.85% interference frequency · a ^{-1 and 0.28% · a ^{-1 , return interval gap of about 357a. Way of gap formed by the trees dry off the most common, accounting for 58.04% total wood formation, followed by windthrow because uprooting formed, accounting for 33.48%. Most gaps formed by the two trees, the average gap has formed wood 2.33. Expanded gap size more in the 100 ~ 300m ^{2 among which 200 ~ 300m ^{2 by area occupied by the largest proportion, and to 100 ~ 200m ^{2 The number of those who occupied the largest proportion. The size of canopy gaps more in the 100m ^{2 or less, of which 50m ^{2 以下 occupied area ratio and the ratio of the number are the largest. Wood distribution of gap formation in the largest diameter class between 20 ~ 30cm. By Wan Lin Zhonglin subtropical evergreen broad-leaved forest gaps and non-gap stands investigation, analysis of the main tree species in gaps within and outside the quantitative characteristics of tree species on the size of the update gaps reaction rule. The results showed that: different species within the gaps and non-gap stands frequency of occurrence, density and significantly varying degrees, thus demonstrating its important values ??are different. Different tree species on the size of the update response gaps showing different variations Hill alum (Symplocos surnuntia) gap in the forest area of ??100m ^{2 or so its update density reaches the maximum Schima (Schima superba) in gap size of 300 ~ 400m ^{2 , its updated density reaches the maximum density of several other updates are in the gap area of ??100 ~ 200m ^{2 is maximized. Nature reserve on Wanmulin subtropical evergreen broadleaf forest gaps within and outside the main tree species niche breadth and niche overlap were studied. The results showed that: Northern Guangxi and Zhejiang Litsea performance both inside and outside the gaps occupy a higher niche breadth. Biological and ecological characteristics of the species close to the height of the larger niche overlap, otherwise small. Gaps in the forest, the mountains alum (Symplocos sumuntia) and a thin Hayama alum (Symplocos anomala) the height of the largest niche overlap, while Northern Litsea (Litsea subcoriacea) and Huang Jui-wood (Adinandra mellettii), pointed leaves Sycopsis ( Distyliopsis dunnii), Zhejiang Gui (Cinnamomum chekiangense) and pointed leaves water silk pear (Distyliopsis dunnii) the height of the niche overlap is small; within gaps in the non-mountain alum and Huang Jui-wood and the maximum height of niche overlap, Northern Litsea Son and pointed leaves Sycopsis, Huang Jui-height wooden niche overlap is small. Application of species diversity richness index, diversity index, evenness and dominance index and other indicators measuring Wanmulin Nature Reserve within subtropical evergreen broadleaf forest gaps and non-gap stands of species diversity and species diversity With gaps the size of the variation. The results showed that: Wanmulin evergreen broad-leaved forest species diversity within gaps than non-gaps, tree species diversity gap size variation with bimodal curve, species diversity in the 200 ~ 300m ^{2 and 500m ^{2 gaps around the maximum; shrub species diversity with the gap size showed a single peak curve, Fujian subtropical evergreen broad-leaved species of Gap dynamics and diversity of forest biological diversity In the area of ??400-500 mZ gap reached the most people. According to Wan subtropical evergreen broad-leaved species inside and outside of Gap survey data to study districts gap gradient of species diversity, species diversity with different sized gaps of forest gap gradient. The results showed that: the central area from the gap area to the non-gap species richness and species diversity index decreased; individuals of species and ecological dominance index was low middle high end trends; evenness was low in the middle ends high trend. Gaps in the area of ??200-300m ', the species diversity gaps districts have reached the most people. Application of the logarithmic model - subtropical evergreen broad-leaved species abundance of Gap predict and test. The results showed that: - subtropical evergreen broad-leaved forest trees and shrubs outside gap material abundance species have followed a logarithmic series distribution. This article - subtropical evergreen broad-leaved forest gap two marginal zone, using Shannon-Wiener diversity index, ecological dominance index and edge effect intensity index, its edge effect phenomenon studied. The results showed that: the determination of species diversity indices mesial area gap edge effect intensity value of 0. glgdel two 035, marginal zone gap edge effect intensity value of 0.8797 ~ 1.2119; but with the determination of the value of ecological dominance mesial area gap edge effect intensity value of 0.4235 ~ l Factory 764, Lin marginal gap edge strength value 06023-2.5099. Mesial area gap edge effect intensity increases with the gap size has increased, while the marginal zone of the gap edge effect intensity gap area of ??400-500 m 'is the smallest. Right - subtropical evergreen broad-leaved forest gap dynamics and forest landscape pattern were studied. The results show that: with the continuous development gaps, gaps canopy gaps plaque more irregular shapes, gaps patch shape canopy gaps deepening fragmentation and gaps canopy gaps plaque fractal dimension is smaller. Plaque gap canopy gaps smaller than the fractal dimension of the plaque expanded gap fractal dimension. By Wanmulin evergreen broad-leaved forest gap research, normally updated on vegetation plays an important role in the maintenance of forest biodiversity important environment, which for us in the subtropical evergreen broad-D-l, simulate natural forest implementation Deforestation update system, providing an important reference.}}}}}}}}}}}}

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