Boone R, Westwood R
Department of Botany, University of Manitoba, Winnipeg, Manitoba, Canada.
Environ Monit Assess. 2006 Oct;121(1-3):151-72. doi: 10.1007/s10661-005-9112-6. Epub 2006 Jun 1.
A forest health assessment was performed in stands dominated by bur oak and trembling aspen to study the potential effects of airborne emissions from a 132 MW coal-fired station. Forty-two stands were sampled within a 16-km radius of the station for both foliar stress symptoms and trace element toxicology. The concentrations of tracer elements (As, Ba, Sr, and V) in the leaf litter were not spatially congruent with airborne emission deposition models (except Ba, which showed elevated levels immediately SE of the station), nor were they at phytotoxic levels. Elemental concentrations were significantly related to soil parameters including organic matter and texture. No patterns were found in forest health along directional or distance gradients from the generating station. Trembling aspen stands demonstrated little decline in general, but three of the 19 bur oak plots, all located on thin sandy soils developed on calcareous till, demonstrated branch dieback. In addition to poor soil conditions, two of these sites also had high water tables, and exhibited tree mortality. The bur oak decline did not appear to be related to emissions from the station, but is suspected to be a result of poor site quality, with urban development as a confounding factor.
在以黑栎和颤杨为主的林分中进行了森林健康评估，以研究一座132兆瓦燃煤电站的空气排放的潜在影响。在该电站半径16公里范围内的42个林分中，对叶片胁迫症状和微量元素毒理学进行了采样。落叶中示踪元素（砷、钡、锶和钒）的浓度在空间上与空气排放沉积模型不一致（钡除外，钡在电站东南方向立即显示出升高的水平），也未达到植物毒性水平。元素浓度与包括有机质和质地在内的土壤参数显著相关。在距发电站的方向或距离梯度上，未发现森林健康方面的模式。总体而言，颤杨林分几乎没有衰退，但19个黑栎样地中有3个，全部位于钙质冰碛土发育的薄沙质土壤上，出现了枝条枯死。除了土壤条件差外，其中两个地点的地下水位也很高，并出现了树木死亡。黑栎的衰退似乎与电站排放无关，但怀疑是由于立地质量差，城市发展是一个混杂因素。
