川中丘陵区防护林群落多样性研究

Btudles on the Communtiy Diversity of the Protection Forest in the Hilly Areas of central Sichuan

本文对川中丘陵地区主要防护林群落的物种多样性进行研究 ,结果表明 :1该流域共有维管束植物 55科 ,82属 ,88种 ,其科、属、种数与四川省乃至全国比较 ,官司河流域植物区系具有组成简单的特点 ;2物种丰富度 ,物种多样性和均匀度指数都是人工林低于天然次生林 ,纯林林分低于混交林分 ;3土壤 p H值、土壤有机质、土层厚度和人为干扰是影响防护林群落多样性发育的重要制约因子 ,其中土壤 p H值是主导因子 ,制约着本区防护林群落的空间分布格局 ;4林木高度、郁闭度和灌、草层盖度与物种丰富度、物种多样性指数和均匀度指数相关密切 ,对群落多样性发育的影响较大 ;而林木胸径与群落多样性指数相关不明显 。

Biodiversity of main protection forests has been studied in hilly areas,results show that.(1) vascular plants are about 55 families,81 generas and 91 species,compared to that of sichuan province and the whole nation,flora composition is comparaticely simple in hilly areas.(2)species richiness,species dicersity index and eveness index of artificial forests are lower than natural regeneration forests,pure forests lower than mixed forests.(3)soil pH(soil acidity and alkalinity).sil organism.soil depth and human disturbance conditions restrict the biodiversity development of protection forests,soil pH of which is a main restricted factor that dominates the disrtibution pattern of protection forests.(4)tree height.canopy density and the coverage of shrub layer and herb layer are ciosely related to species richness diversity index and eveness index,which have a great influence on the development of community diversity.However,the relationship between tree diameter at breast height and community diversity index is not close,it shows that tree height has not an outstanding influence on the development of community diversity.