珠防工程实施初期植物群落变化研究

通过在珠防工程区的典型地段设置样地并定期进行调查,对工程二期近三年植物群落的变化进行了初步研究,结果表明:珠防工程实施初期造林树种的高、径净生长量都比较小,针叶树普遍较阔叶树的净生长量大,并且随着造林年限的增加,高、径净生长量均表现为增加趋势;通过珠防工程的实施,植物群落朝着稳定的方向发展,生物量不断提高;在人工造林中,造林树种的生物量占总生物量的比重大于灌木、草本生物量;同一时间实施的珠防工程,人工造林的生产力比封山育林高;工程实施初期随造林时间的延长,群落的生产力表现出增加趋势;同一造林时间不同的群落类型,其生产力表现出很大差异:植被盖度及造林树种盖度增加最大,灌木次之,草本最小;植物物种多样性主要表现在草本种类的增加,灌木变化幅度较小,人工造林比封山育林更能促进物种多样性。

The Change of the Plant Community in Pear River Sheltbelt

By setting plots and investigating regularly,the change of the plant community of Pearl River sheltbelt in recent three years was studied.The result showed that the plant community is approaching its stability and the bio-mass keeps increasing;In the artificial plantation,the bio-mass ratio of trees is higher than that of the shrub and grass;The productivity of the artificial plantation is higher than that of the closed forest;As the time goes on,the productivity of the community is increasing,but the differences occur in different community types;In terms of the coverage,the coverage of the artificial plants is the highest,and the coverage of the grass is the lowest.The artificial plantation is better than closed forest for improving the biodiversity.