酸雨对杨树生长和木材化学性质的影响

对受酸雨危害和未受酸雨危害杨树的年轮宽度和木材化学性质的对比研究表明：酸雨对杨树生长和木材化学性质产生了明显的影响。酸雨会导致树木生长减缓，年轮宽度变窄，受害材的年轮宽度较健康材相对降低１２．６７％。受害材与健康材的ｐＨ值无明显差异，酸、碱缓冲容量有显著差异。与健康材相比，受害材的戊聚糖和木质素含量相对升高１．４３％和３．７２％，而综纤维素的含量相对减少３．４５％，灰分的含量相对减少８．３４％。受

THE EFFECTS OF ACID RAIN ON %POPULUS EURAMERICANA% TREE RING WIDTH AND WOOD PROPERTIES

The tree ring width, pH value, wood chemical composition and element contents of poplars selected from healthy and acid rain damaged forests were analysed to evaluate the possible impacts on wood properties. Acid rain affected tree growth slower, tree|ring width narrower, tree|ring width of diseased tree decreased 12.67%. The pH values did not significantly differ. Compared with healthy trees, the content of holocellulose in diseased tree decreased 3.45%, but pentosan and lignin contents in diseased trees were higher than in healthy trees. Extractive content between diseased trees and healthy trees showed significant difference. The contents of K, Na, Ca, Mg in diseased trees were lower, but the content of Cu and S in diseased trees were significantly higher. Soluble sugars content in diseased trees was higher than in healthy trees. The results showed that there were a lot of differences in wood chemical properties between diseased trees and healthy trees.