青藏高原垫状植物利它作用与微环境的关系

Cushion plants, as pioneers in the succession of vegetation on the Tibetan Plateau, can create a unique microhabitats through their dense structure. The generated microhabitats then facilitate the survival and recruitment of other plant species, resulting in an increase in species richness in alpine ecosystems. To our knowledge, however, the current knowledge about nurse effect of cushion plant and its physio-ecological mechanism is not clear. In this project, we conducted a livestock exclosure experiment across the upper (5500m) and lower (4400m) limits of cushion species (Androace tapete and Thylacospermum caespitosum) along the south-facing slope of the Nyainqêntanglha Mountain during the period 2006-2020. The plant phenology and growth indexes across the fenced and unfenced quadrats were observed near weather stations at 10 altitudes. We aim to 1) clarify the pattern nurse effect cushion plant along the altitude and its effect of temperature and precipitation changes; 2) explore the ecological function of cushion plants in alpine grassland ecosystems and their responses to future climate change. These results can provide some scientific data and theoretical support for understanding the response of the Qinghai - Tibet Plateau to global change.

垫状植物被认为是青藏高原的先锋植物，其独特的结构可能直接为其他植物提供庇护，也可能通过改变局部环境而有利于其它植物生存。但是，这些利它作用的现状及其生理生态学机制并不清楚，在气候变暖背景下会如何变化就更不清楚。本研究以垫状点地梅和囊种草为研究对象，利用念青唐古拉山南坡海拔梯度（4400m到5500m）10个样地和降海拔移植实验平台（3个海拔），通过长期（2006-2020）垫状植物对其它植物生长和物候的观测数据，结合连续观测的微气象观测和土壤养分数据，试图阐明垫状植物利它作用随海拔变化的规律以及利它作用对温度降水等环境变化的响应。由此进一步探讨垫状植物在高寒草地生态系统的生态功能及其对未来气候变化的响应，这些结果可以为理解青藏高原对全球变化响应提供部分科学数据和理论支撑。