秦岭主要森林类型近自然度评价

Naturalness Assessment of the Main Forest Communities in Qinling Mountains

选择秦岭火地塘林区7个森林类型,在样地调查的基础上,基于敏感性分析,选择17个反映森林类型特征的指标,运用层次分析法建立秦岭主要森林类型近自然度评价指标体系,应用综合指数法建立评价数学模型。根据等间距法,将森林类型近自然度评价综合指数划分为5个等级。评价结果表明:秦岭7个主要森林类型即铁杉天然次生林、锐齿栎天然次生林、华山松天然次生林、红桦天然次生林、华山松人工林、油松人工林、华北落叶松人工林的近自然度评价综合指数分别为0.98,0.90,0.78,0.56,0.39,0.35,0.01,近自然度等级分别为1,1,2,3,4,4,5,铁杉和锐齿栎天然次生林处于近自然状态,其他林分分别处于半自然、远天然、近人工和人工状态,近自然度顺序表现为顶极群落森林>演替过渡群落森林>先锋群落森林>乡土树种人工林>外来树种人工林。评价结果与该区森林天然性程度相吻合,证明评价指标体系和模型的适用性。针对不同森林类型的近自然度,提出相应的经营措施。

Naturalness assessment was a basic work for natural forest management and it also could be used to propose reasonable measures for forestation.This study was carried out in Qinling mountain where most forests were natural secondary forests and our objective was to assess naturalness of the main forest types in this region.The data were collected from 35 stand plots and 105 soil samples.On this basis,through sensitivity analysis of 30 indexes which describes the community characteristics,17 indexes were filtered out and used to establish an assessment index system.Integrated indexes were analyzed with the analytic hierarchy process （AHP） to build a model for assessing the naturalness.The results showed that： The integrated indexes of naturalness of Tsuga chinensis secondary forest,Quercus aliena var.acuteserrata secondary forest,Pinus armandii secondary forest,Cephalotaxus sinensis secondary forest,Pinus armandii plantation,Pinus tabulaeformis plantation,Larix principis-rupprechtii plantation were 0.98,0.90,0.78,0.56,0.39,0.35,0.01 and their naturalness classifications were 1,1,2,3,4,4,5 respectively.Tsuga chinensis secondary forest,Quercus aliena var.acuteserrata secondary forest were Near -natural forest,other forests were semi-natural forest,Far from-natural forest,Near-plantation and plantation,respectively.The order of naturalness was climax community transition succession community pioneer community native seedling plantation exotic seedling plantation.The assessment results fitted the actual situation well,which indicated the index system had good performance in this region.According to the naturalness of different forest types,some corresponding measures of management were proposed.