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本篇论文报道了挪威针叶树树冠密度与自然因素之间的联系。这项研究的结果结合监测潜在由空气污染物引起的森林衰退问题进行了讨论。挪威云杉(Picea abies)树冠密度方差的43%是由生产力等级、树龄和4月及7月份的平均温度引起的;对于冠色,其方差的11%是由生产力等级、树龄和样地坡向引起的。松树的冠色和树冠密度的变异小,所以结果比较分散。我们用这些观测资料对样地分层,发现在污染最严重的地区,树冠密度相对低的样地出现次数较高。由于样本数量太少,以致于不能说明真实的区域格局。为了避免把空气污染物与自然因子混淆,需要预先对样地进行分层,特别是要按照树龄和气候进行分层。这样,通过对每层内相对最差的森林空间分布的调查,就可以用来识别受自然因子影响较小的情况下的格局,并且有助于识别空气污染物对森林生态系统在其他方面未被察觉的效应。
This paper reports the link between the canopy density of Norway conifers and natural factors. The results of this study, combined with the monitoring of potential forest degradation caused by air pollutants, are discussed. 43% of the canopy density variance in Norway’s Picea abies was caused by productivity level, tree age, and average temperature in April and July; for crown color, 11% of variance was determined by productivity level, tree age, To cause. Pine Crown crown and crown density variation is small, so the results are more scattered. Using these observations, we stratified the plots and found that in the most polluted areas, samples with relatively low canopy density appeared more frequently. Due to the small number of samples, the true regional pattern can not be explained. In order to avoid confusion between air pollutants and natural factors, it is necessary to stratify the plots beforehand, especially stratification by age and climate. In this way, surveys of the relative worst spatial distribution of forests within each floor can be used to identify patterns that are less affected by natural factors and to help identify the impacts of air pollutants on forest ecosystems in other ways Spotted effect.