植物生态学报 ›› 2025, Vol. 49 ›› Issue (1): 74-82.DOI: 10.17521/cjpe.2024.0095  cstr: 32100.14.cjpe.2024.0095

• 研究论文 • 上一篇    下一篇

高寒草甸退化过程中土壤种子库的变化及其在植物群落更新中的潜在作用

张辉, 赵赟鹏, 刘晓琛, 郭增鹏, 胡国瑞, 冯彦皓, 马妙君*()()   

  1. 兰州大学生态学院, 草种创新与草地农业生态系统全国重点实验室, 甘肃甘南草原生态系统国家野外科学观测研究站, 兰州 730000
  • 收稿日期:2024-04-02 接受日期:2024-10-24 出版日期:2025-01-20 发布日期:2025-03-08
  • 通讯作者: * 马妙君: ORCID: 0000-0001-7046-9574 (mjma@lzu.edu.cn)
  • 基金资助:
    中国科学院战略性先导科技专项(A类)(XDA26020202)

Dynamics of soil seed bank and its role in plant community regeneration during alpine meadow degradation

ZHANG Hui, ZHAO Yun-Peng, LIU Xiao-Chen, GUO Zeng-Peng, HU Guo-Rui, FENG Yan-Hao, MA Miao-Jun*()()   

  1. College of Ecology, State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, Lanzhou University, Gannan Grassland Ecosystem National Observation and Research Station, Lanzhou 730000, China
  • Received:2024-04-02 Accepted:2024-10-24 Online:2025-01-20 Published:2025-03-08
  • Supported by:
    Strategic Priority Research Program of the Chinese Academy of Sciences(XDA26020202)

摘要:

青藏高原东部高寒草甸局部地区因长期过度放牧而发生退化。土壤种子库是退化生态系统恢复的潜在重要资源, 其在高寒草甸退化过程中的动态及其在退化草地恢复中的作用仍有待探究。该研究在青藏高原东部选择了4个不同退化水平的高寒草甸, 构建了一个退化序列。在这一序列上对植物群落和土壤种子库进行调查, 探究了植物群落及种子库组成和特征在退化序列上的变化规律, 并分析了种子库在植物群落更新和退化高寒草甸恢复中的潜在作用。研究发现: (1)植物群落的物种丰富度和相对多度随高寒草甸的退化而显著降低, 而土壤种子库的物种丰富度呈现先升高后降低的变化规律, 种子密度则显著降低; (2)植物群落与土壤种子库物种组成相似性随退化水平增加而逐渐增加, 即种子库在植物群落更新中的潜在作用随退化水平的增加而增加; (3)相比于植物群落, 种子库对退化的响应有明显的滞后性, 可以在一定程度上缓冲退化对地上植物群落的影响。以上结果说明, 高寒草甸植物群落和土壤种子库对退化的响应不一致, 土壤种子库是退化高寒草甸恢复的重要潜在资源。然而, 土壤种子库对退化的恢复潜力是有限的, 在重度退化水平下, 由于种子库资源的过度损耗, 种子库在修复中的作用下降。以上研究结果可为青藏高原退化高寒草甸的保护、恢复和管理提供科学依据。

关键词: 高寒草甸, 退化, 恢复, 土壤种子库, 青藏高原, 植物群落

Abstract:

Aims The alpine meadows on the eastern Qingzang Plateau have degraded in some areas due to long-term overgrazing. As a crucial resource for degraded ecosystem restoration, the dynamics of soil seed banks and their role in degraded alpine meadow restoration remain unclear.

Methods We chose four different degradation levels of alpine meadows to construct a degradation gradient on the eastern Qingzang Plateau. We investigated the plant community and soil seed bank along the degraded gradient, explored the changes of plant community and seed bank along the degradation gradient, and analyzed the potential role of seed banks in alpine meadow regeneration and degraded alpine meadow restoration.

Important findings The results showed that: 1) the species richness and relative abundance of the plant community decreased significantly along the degradation gradient, but the species richness of the seed bank increased first and then decreased, and the seed density decreased significantly along the degraded gradient. 2) The similarity of species composition between the plant community and soil seed bank gradually increased with the degradation gradient, which suggests that the role of soil seed bank in plant community regeneration increased along the degraded gradient. 3) Compared with the plant community, there is a hysteresis response of the soil seed bank to alpine meadow degradation, which can buffer the influence of alpine meadow degradation on the plant community to a certain extent. Our findings indicated that the different responses of plant community and soil seed bank to degradation, and soil seed bank is crucial for the degraded alpine meadow restoration on the Qingzang Plateau. However, the potential role of the seed bank in the degraded alpine meadows restoration will be limited because of the depletion of seed bank resources at the seriously degraded level. These results can provide a scientific basis for the protection, restoration, and management of degraded alpine meadows on the Qingzang Plateau.

Key words: alpine meadow, degradation, restoration, soil seed bank, Qingzang Plateau, plant community