乌拉山自然保护区主要森林群落物种多样性与群落结构研究

乌拉山自然保护区位于典型草原与荒漠草原的交界处,是研究干旱区山地物种多样性的理想区域。利用α多样性指数、β多样性指数以及重要值,对乌拉山主要森林群落（白桦林、油松林）林下灌木层和草本层的物种多样性以及群落结构进行了研究,结果表明：（1）群落草本层α多样性指数明显高于灌木层;（2）群落灌木层、草本层α多样性指数表现为：白桦林〉天然油松林〉人工油松林;天然油松林〉人工油松林〉白桦林〉柄扁桃灌丛;（3）群落β多样性指数表现出同一种森林群落类型之间绝大多数呈轻度相似性;不同森林群落类型之间呈极不相似;生境条件的差异、人为干扰等因素对群落β多样性的影响较为明显;（4）群落物种组成以菊科、蔷薇科植物为主,草本植物以多年生中生、中旱生、旱生植物为主,林下灌木水分生态型以中生为主。

Community Structure and Species Diversity of Main Forest Community in Wulashan Nature Reserves, Inner Mongolia

Located in juncture of typical steppe and desert grassland,Wulashan Nature Reserves is an ideal area for studying arid mountainous species diversity.In this paper,α diversity index,β diversity index and important values have been applied to study the species diversity and community structure of shrub layer under trees and herbaceous in the main forest communities（Betula platyphylla forest and Pinus tabulaeformis forest）.The results show：（1） α diversity index of herbaceous layer is obviously higher than the shrub layer in community;（2） the sequence of α diversity index of the shrub and herbaceous layer in community is： Betula platyphylla forest〉Pinus tabulaeformis natural forest〉Pinus tabulaeformis plantation,Pinus tabulaeformis natural forest〉Pinus tabulaeformis plantation〉 Betula platyphylla forest〉Prunus pedunculata shrubs;（3） β diversity index shows that in the same forest community,most of them are in mild similarity,and in the different forest community,it is in extreme dissimilarity.The habitat conditions and human disturbance can influence the β diversity index obviously;（4） the community species are mainly Compositae and Rosaceae plants,perennial meadow herb,mid-xeric herb and xeric herb.The water ecotype of understory shrub is mainly mesophilous shrub.