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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 ,对群落多样性发育的影响不大
In this paper, the species diversity of the main shelterbelts in the hilly area of central Sichuan was studied. The results showed that: 1 The total number of vascular plants was 55, 82 and 88 in the basin, and their families, genera and species were compared with those in Sichuan and the whole country. The flora of the river basin has the characteristics of simple composition. 2 The species richness, species diversity and evenness index of plantation are lower than that of natural secondary forest, pure forest is lower than that of mixed forest. 3 Soil p H, soil organic matter, Soil thickness and man-made disturbance are important constraints that affect the diversity of shelterbelts. The soil p H value is the dominant factor, which restricts the spatial distribution pattern of shelterbelts in this area. 4 The height, canopy density, Cover degree is closely related to species richness, species diversity index and evenness index, and has a great influence on community diversity development. However, the correlation between DBH and community diversity index is insignificant, and it has little effect on community diversity development