雅鲁藏布江上游高寒草甸地上生物量与多样性沿海拔梯度的变化特征

【目的】雅鲁藏布江是青藏高原最重要的河流，研究雅鲁藏布江的地上生物量和物种多样性对了解该区域的草地资源和生态保护具有重要意义。【方法】文章根据海拔梯度对雅鲁藏布江上游高寒草甸植被特征进行调查，研究不同海拔梯度下地上生物量和物种多样性的分布差异、地上生物量与物种多样性之间的关系，以及相关环境因子对地上生物量和物种多样性的影响。【结果】(1)海拔与地上生物量无显著关系；(2)海拔与多样性指数呈显著负相关关系，随海拔升高Shannon-Weiner指数、Patrick指数表现为下降趋势；(3)地上生物量与多样性之间表现为负相关关系，Shannon-Weiner指数对地上生物量的解释达到70%(P＜0.01)；(4)物种多样性与温度和降水呈显著正相关关系(P＜0.05)，物种多样性与海拔呈负相关关系(P＜0.05)，地上生物量与海拔、温度和降水无显著关系(P＞0.05)。【结论】该研究结果有助于为雅鲁藏布江上游流域草地资源的合理利用和物种多样性保护提供依据。

Characteristics of aboveground biomass and diversity in alpine meadows of the upper Yarlung Zangbo River along an altitudinal gradient

【Objective】 The Yarlung Zangbo River is the most important river on the Tibetan Plateau, and the study of aboveground biomass and species diversity of the Yarlung Zangbo River is of great significance to the understanding of grassland resources and ecological conservation in the region. 【Methods】 This study investigated the vegetation characteristics of alpine meadows in the upper reaches of the Yarlung Zangbo River according to the elevation gradient, and studied the distributional differences of aboveground biomass and species diversity at different elevation gradients, the relationship between aboveground biomass and species diversity, and the effects of related environmental factors on aboveground biomass and species diversity. 【Results】 (1) There was no significant relationship between elevation and aboveground biomass. (2) Elevation and diversity indices showed a significant negative correlation: the Shannon-Weiner index and Patrick index showed a decreasing trend with elevation. (3) Aboveground biomass and diversity showed a negative correlation, and the explanation of aboveground biomass by the Shannon-Weiner index reached 70% (P<0.01). (4) Species diversity showed a significant positive correlation with temperature and precipitation (P<0.05), species diversity showed a negative correlation with elevation (P<0.05), and aboveground biomass had no significant relationship with elevation, temperature and precipitation (P>0.05). 【Conclusion】 The results of this study can help to improve the basis for the rational utilization of grassland resources and species diversity conservation in the upper Yarlung Zangbo River basin.