亚热带季风常绿阔叶林原始林和次生林植物虫食的研究

亚热带季风常绿阔叶林原始林的日间最高气温、昼夜温差和林间光强较次生林低。原始林叶片受虫食的Ⅱ、Ⅲ和Ⅳ级的比例分别为16.3％、15.4％和12.2％;次生林相应等级比例分别为21.4％,24.3％。和17.7％。两林地植物老叶和成热叶受虫食的频度较幼叶的高。叶片受虫食与光强有关,与叶片含氮量没有直接关系。

HERBIVORY ON PLANTS IN NATIVE AND SUCCESSION SITES OF SUBTROPICAL MONSOON FOREST

Two study sites were selected at Ding Hu Shan, Guangdong province. At the forest floor of native site, plants received a small a-mount of solar irradiance and associated less fluctuation of day/night temperature due to the presence of overtopping canopy species. But at succession site,plants received much higher daily irradiance and had higher day/ night temperature fluctuation. Herbivory on each plant of these sites was estimated by visual classification on leaf of 3 shoots per plant indicated by leaf area loss (>2%, 2-10%, 10-20%, 25-50%, >50%). The results showed that greater proportion of healthy leaves (38.9%) in plants grown in native site and leaves sustained herbivory of 16.3%, 15.4%, and 12.2% in leaf area loss which is equivalent to Ⅱ,Ⅲ and Ⅳ class respectively, while corresponding values of 21.4%, 24.3% and 17 .7% were found in plants of succession site. Leaves of old ages sustained herbivory of 38.8%, 62.9% and 60.7% in leaf area loss in plant of native site, respectively 41.5%, 46.5% and 31.6% in plants of succession site, while it was respectively.Leaf nitrogen content in plants from the native site was higher than that in plants at the succession site. It is to be likely that herbivory is related to light intensity of the site, but it was not directly related to leaf nitrogen.