大气污染对杉木生长的影响

通过大气污染地区和清洁区的标准地调查、树干解析以及木材含污量的分析测定表明,大气污染对杉木林缘木生长的抑制作用最明显。林缘木和林内木比较,杉木林幼年时期林缘效应和污染效应均不明显。森林郁闭后,清洁区表现出明显的林缘效应,污染区则表现出明显的污染效应。根据立地条件、营林措施相似的森林地区的林缘效应和污染效应,可以估测林木生长损失率。大气污染会使受严重污染影响的林缘木形成假年轮。杉木木材历年的含污量与相应年轮宽度呈指数负相关关系。根据相关方程,可以推断污染历史。

Effect of Atmospheric Pollution on Growth of Chinese Fir

An inventory to the sample plots of atmospheric polluted area and the area without atmospheric pollution, a stem analysis and a pollution analysis of timber showed that atmospheric pollution could check the growth of edge trees greatly; the effect of forest edge and the pollution effect were not distinct between the edge trees and the trees within stand of young Chinese fir, but, for canopied Chinese fir, there were a obvious effect of forest edge in the area without atmospheric pollution and a obvious pollution effect in atmospheric polluted area, which could indicate the loss rate of forest growth; the edge trees, after being polluted seriously, would form false growth ring, and there was a negative index correlation between the annual pollution content of Chinese fir and the width of annual ring, which could infer pollution record of Chinese fir.