青海省高寒灌丛物种多样性、生物量及其关系

物种多样性对生态系统功能的作用是生物多样性研究的核心领域之一,生物量水平是生态系统功能的重要表现形式,而植物群落的生物量则是生态系统生物量的基础,因此研究植物群落物种多样性与生物量的关系,对于阐明植物多样性对生态系统功能的作用具有重要意义。通过对青海省高寒灌丛生物量、灌丛物种多样性特征以及与生物量的关系调查,得到以下结果:(1)被调查灌木植被群落的40个样地中共出现了207种植物(其中灌木植物18种,草本植物189种),隶属于130属,43科,灌木以蔷薇科、杜鹃花科为主,而草本以菊科、龙胆科、毛茛科和莎草科占优势。(2)群落多样性指数偏低,植物群落结构简单,物种组成稀少。小叶金露梅群落的多样性指数最大,金露梅群落、细枝绣线菊群落和鲜卑花群落次之,百里香杜鹃+头花杜鹃群落最低。(3)不同高寒灌丛类型生物量介于1893.03—7585.41 g/m~2之间,平均值为3775.9 g/m2,其中灌木生物量占灌丛总生物量的73.55%,草本为26.45%。(4)总生物量随草本物种多样性和群落物种多样性的增加而减小;草本生物量随其物种多样性的增加而减小,而灌木物种多样性与其生物量并无显著相关性。

Species diversity, biomass, and their relationship in the alpine shrubberies of Qinghai Province

The relationship between species diversity and ecosystem function is one of the core problems on biodiversity research. Biomass is an important modality of ecosystem function. The species diversity of natural communities is often strongly related to their biomass. Therefore, studies on the relationship between species diversity and biomass in plant communities is of great significance to understand the role of plant diversity on ecosystem functioning. In this paper, the biomass, distribution patterns, relationship between species biodiversity and biomass in alpine shrubberies of Qinghai have been researched based on the surveyed data of the shrubberies. The results show that (1) the investigated plants belong to 207 species (including 18 kinds of shrubs and 189 kinds of herbs) under 130 genera and 43 families. Most of the shrubs belong to the Rosaceae and Ericaceae families, while the dominant herb families were Asteraceae, Gentianaceae, Ranunculaceae, and Cyperaceae; (2) The shrub community species diversity indices are generally low, the species diversity indices of Potentilla parvifolia community are larger; the species diversity index of Potentilla fruticose community, Spiraea myrtilloides community and Sibiraea laevigata community are second, while that of Rhododendron thymifolium+Rhododendron capitatum community is lower; (3) the biomass of the alpine shrubberies of Qinghai varies from 1893.03 to 7585.41 g/m² (with an average of 3775.9 g/m²), where the biomass of the shrub layer accounts for 73.55%, and that of the herb layer accounts for 26.45%; (4) the biomass of shrubberies decrease significantly with the increase of species diversity at the herb layer and that of the communities, but it does not decrease with the increase of species diversity of the shrub layer. The biomass of the herb layer decreases significantly with the increase of the species diversity within this layer, but there is no significant correlation between the biomass of shrub layer and its species diversity.