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森林自然度的計量模型研究

發(fā)布時間:2018-04-26 00:34

  本文選題:森林自然度 + 林層指數(shù) ; 參考:《中南林業(yè)科技大學》2013年碩士論文


【摘要】:由于全球森林生態(tài)系統(tǒng)嚴重退化的現(xiàn)狀,如何保護和恢復森林生態(tài)系統(tǒng)已經(jīng)成為世界關(guān)注的焦點。而將原生植被群落與現(xiàn)實植被群落在群落特征、生境狀況等方面作對比,是恢復森林的基礎(chǔ)。因此,評價二者的差異,即計算森林自然度是恢復退化的森林生態(tài)系統(tǒng)工作中的重點,是天然林管護和人工林近自然化改造的關(guān)鍵所在。 本文屬于國家自然科學基金“洞庭潮濕地森林生態(tài)系統(tǒng)經(jīng)營的空間途徑研究(項目編號31070568)”、林業(yè)公益性行業(yè)科研專項“南方集體林區(qū)次生林撫育間伐與高效利用技術(shù)研究(項目編號201004032)”和湖南省自然科學基金資助項目“基于多目標優(yōu)化的水源涵養(yǎng)林空間結(jié)構(gòu)模式研究(項目編號10JJ2022)”的部分研究內(nèi)容。本研究在綜合國內(nèi)外森林自然度研究理論的基礎(chǔ)之上,通過運用粗糙集理論和變異系數(shù)法,構(gòu)建了森林自然度的計量模型,然后以龍虎山林場青i混交林、桂花林場苦櫧混交林和擦木混交林為研究對象,對三種林分的森林自然度進行了計算,并給出了近自然經(jīng)營的建議。最后得到結(jié)論如下 (1)提出了林層指數(shù)、自然構(gòu)成指數(shù)、干擾指數(shù)三個新指標。從而能更準確地反映林分的垂直分布格局、描述森林的演替方向和分析森林受干擾的程度。 (2)提出了一種基于粗糙集理論的森林自然度計量模型。該模型利用粗糙集的屬性約簡思想對指標進行篩選。 (3)對森林自然度的計量模型進行了實例分析,以龍虎山林場青i混交林、桂花林場苦櫧混交林和檫木混交林為研究對象,進行了森林自然度計量模型的運算,得出三種林分的森林自然度分別是0.741、0.727、0.593,分別屬于森林自然度等級中的Ⅱ級、Ⅱ級、Ⅲ級。
[Abstract]:Due to the serious degradation of global forest ecosystem, how to protect and restore forest ecosystem has become the focus of the world. Comparing primary vegetation communities with real vegetation communities in community characteristics and habitat conditions is the basis for forest restoration. Therefore, the evaluation of the difference between the two is that the calculation of forest naturalness is the key point in the restoration of degraded forest ecosystem, and the key to natural forest management and the near naturalization of artificial forest. This paper belongs to the National Natural Science Foundation of China, "Research on Spatial approaches to the Management of moist Forest ecosystem in Dongting (Project No. 31070568)". Forestry Public Welfare Industry Scientific Research Project "Research on thinning and efficient Utilization of Secondary Forest in Southern Collective Forest region (Project No. 201004032)" and "Water Conservation Forest Space Conservation based on Multi-objective Optimization" supported by Natural Science Foundation of Hunan Province Part of the study on Interstructure Model (item No. 10 JJ 2022). On the basis of synthesizing the theories of forest naturalness at home and abroad, the measurement model of forest naturalness was constructed by using rough set theory and variation coefficient method. The forest naturalness of three kinds of forest was calculated, and the suggestion of near natural management was given. The mixed forest of Castanopsis eyrei and mixed forest of wood and wood in Osmanthus fragrans forest farm were studied. The final conclusion is as follows 1) three new indexes of forest layer index, natural composition index and disturbance index are put forward. Thus it can more accurately reflect the vertical distribution pattern of forest describe the succession direction of forest and analyze the degree of forest disturbance. A forest naturalness measurement model based on rough set theory is proposed. The model uses the attribute reduction idea of rough set to filter the index. (3) the measurement model of forest naturalness was analyzed by examples. The calculation of forest naturalness measurement model was carried out by taking the green mixed forest, Castanopsis eyrei mixed forest and sassafras mixed forest in Longhu Mountain Forest Farm as the research objects. The results showed that the forest naturalness of the three stands was 0.727270.593, which belonged to 鈪,

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