Li Yuan, Bao Gensheng, Zhang Peng, Feng Xiaoyun, Ma Jingjuan, Lu Hainian, Shi Hongxiao, Wei Xiaoxing, Tang Bingming, Liu Kai
Academy of Animal and Veterinary Medicine, Qinghai University, Xining, China.
State Key Laboratory of Sanjiangyuan Ecology and Plateau Agriculture and Animal Husbandry, Qinghai University, Xining, China.
Front Plant Sci. 2023 Oct 13;14:1259340. doi: 10.3389/fpls.2023.1259340. eCollection 2023.
Bud banks are considered a crucial factor in regulating the species composition of grassland communities and maintaining the ecological function of alpine grasslands. However, few studies have paid attention to the dynamic changes of bud banks from undisturbed to severely degraded alpine meadows. Therefore, this study examined the correlations between plant diversity and bud bank traits at different stages of alpine meadows degradation. Grass biomasses and plant diversity were found to be highest in moderately degraded meadows, and sedge biomasses were highest in lightly degraded meadows. Lack of disturbance and moderate disturbance by herbivores increased the bud bank density of alpine meadows. Consistent with the changes in bud bank density, bud bank diversity was highest in undisturbed meadows. The structural equation model indicated that the densities of rhizome and the densities and diversities of tiller buds play crucial roles in facilitating the greater diversity of the plant community. Our findings suggest that the diversities and densities of rhizome and tiller buds in the degradation stages are synchronized with changes in plant diversity, and in the regenerative ability of bud banks, which largely determine the outcome of restoration in degraded meadows. These findings could provide a frame of reference for effectively restoring degraded alpine regions by regenerating bud banks. The potential driving force and renewal capacity of bud banks should be taken into account in restoring the Qinghai-Tibet Plateau's degraded meadow.
芽库被认为是调节草原群落物种组成和维持高寒草原生态功能的关键因素。然而，很少有研究关注从未受干扰到严重退化的高寒草甸芽库的动态变化。因此，本研究考察了高寒草甸退化不同阶段植物多样性与芽库特征之间的相关性。结果发现，中度退化草甸的禾本科生物量和植物多样性最高，轻度退化草甸的莎草科生物量最高。缺乏干扰和食草动物的适度干扰增加了高寒草甸的芽库密度。与芽库密度的变化一致，未受干扰草甸的芽库多样性最高。结构方程模型表明，根茎密度、分蘖芽密度和多样性在促进植物群落更丰富的多样性方面起着关键作用。我们的研究结果表明，退化阶段根茎和分蘖芽的多样性和密度与植物多样性的变化以及芽库的再生能力同步，这在很大程度上决定了退化草甸的恢复结果。这些发现可为通过芽库再生有效恢复退化高寒地区提供参考框架。在恢复青藏高原退化草甸时，应考虑芽库的潜在驱动力和更新能力。
