广西细叶云南松森林资源动态分析

Dynamic analysis of Pinus yunnanensis var. tenuifolia Forest Resources in Guangxi

利用1956年至2013年近60年间广西森林资源连续调查监测数据,对细叶云南松(Pinus yunnanensis var.tenuifolia)资源的数量、质量变化进行动态分析,结果表明:在1956~2013年近60年间,细叶云南松林资源总体呈下降趋势,且减少趋势随时间推移愈发明显,面积从1.48万hm^2下降到不足0.3万hm^2,年均递减0.046万hm^2,蓄积量从227.64万m^3下降到28.75万m^3,年均递减3.55万m^3。大径组和特大径组林木蓄积所占比例急剧减少。受连年持续干旱及松小蠹虫危害,损失面积由占总面积的8.55%升高到77.89%。次生幼林是现阶段细叶云南松林分的主要组成形式,表明细叶云南松林的数量和质量在总体上结构低质化倾向愈加显著。人为过度干预、森林火灾、虫害及连年干旱是细叶云南松林资源的数量持续减少、林分质量下降、资源濒临枯竭的主要原因。

The amount of resource and the quality and monitoring data of forest resource from 1956 to change were analyzed by using continuous investigate 2013. The result showed that the resources of the forest continued to decline from 1956 to 2013, and the decrease tendency was increasingly obvious with time lapse. The total area of the forest declined from 1.48 × 10 4 hm2 to 0. 3 × 10 4 hm2and the mean annual de- crease was 0. 046 × 10 4 hm2 ; the total stock volume of the forest declined from 2. 276 4 × 10 6 m3 to 2. 875 × 10 5 m3and the annual decrease was 3.55 × 10 4 m3. The result showed that the proportion of the large diameter and the super- large diameter timber declined rapidly. Continuous drought in successive years and the pine bark beetle damage, the loss area of the forest increased from 8.55% to 77.89%. The secondary forest was the main forest of Pinus yunnanensis var. forest resources. This showed that the tenden- cy of low - quality structure became more and more notable in the quantity and quality of Pinus yunnanensis var. The main reasons for the quality decline, quality reduction and resource exhaustion were the excessive human intervention, forest fires, insect damage as well as successive years of drought.