Li Wencheng, Huang Aiping, Zhou Tiancai, Liu Miao, Ma Sujie, Zhao Ningning, Wang Xiangtao, Sun Jian
Key Laboratory of Alpine Vegetation Ecological Security, Tibet Agriculture and Animal Husbandry University, Nyingchi, China.
State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China.
Front Plant Sci. 2023 Jan 18;13:1095864. doi: 10.3389/fpls.2022.1095864. eCollection 2022.
In grassland ecosystems dominated by asexual plants, the maintenance, renewal, and resistance of plant populations to disturbance are more dependent on the belowground bud bank (BBB). However, the response of the BBB to environmental factors in the alpine grassland of the Qinghai-Tibet Plateau (QTP) is still unknown.
Therefore, a transect survey was conducted to measure the size and scale of BBB and 21 factors in the alpine grassland of the QTP. In addition, the critical driving factors of BBB were screened by boost regression tree analysis, and a structural equation model (SEM) was employed to express the path coefficients of the key factors on the BBB size.
The results showed that BBB size had no significant geographical pattern in the QTP, and the BBB size was mainly accounted for by soil leucine aminopeptidase (LAP, 17.32%), followed by Margalef and Shannon -Wiener indices of plants (12.63% and 9.24%, respectively), and precipitation (9.23%). SEM further indicated significant positive effects of plant diversity (scored at 0.296) and precipitation (scored at 0.180) on BBB size, and a significant negative effect of LAP (scored at 0.280) on BBB size.
Generally, the findings allow for better understanding of the regulated mechanisms of BBB size and the importance of the role of bud bank in the restoration of the grassland ecosystem.
在以无性繁殖植物为主的草原生态系统中，植物种群对干扰的维持、更新和抗性更多地依赖于地下芽库（BBB）。然而，青藏高原（QTP）高寒草原地下芽库对环境因素的响应仍不清楚。
因此，开展了样带调查，以测量青藏高原高寒草原地下芽库的大小和规模以及21个因素。此外，通过增强回归树分析筛选出地下芽库的关键驱动因素，并采用结构方程模型（SEM）来表示关键因素对地下芽库大小的路径系数。
结果表明，青藏高原地下芽库大小没有显著的地理格局，地下芽库大小主要由土壤亮氨酸氨肽酶（LAP，17.32%）决定，其次是植物的Margalef指数和香农-威纳指数（分别为12.63%和9.24%）以及降水量（9.23%）。结构方程模型进一步表明，植物多样性（得分0.296）和降水量（得分0.180）对地下芽库大小有显著的正向影响，而亮氨酸氨肽酶（得分0.280）对地下芽库大小有显著的负向影响。
总体而言，这些发现有助于更好地理解地下芽库大小的调控机制以及芽库在草原生态系统恢复中的重要作用。
