State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A & F University, No. 26, Xinong Road, Yangling, 712100, China.
Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resource, Yangling, 712100, China.
Oecologia. 2023 Jun;202(2):251-259. doi: 10.1007/s00442-023-05393-y. Epub 2023 May 31.
The community stability is the main ability to resist and be resilient to climate changes. In a world of climate warming and melting glaciers, alpine gravel encroachment was occurring universally and threatening hillside grassland ecosystem. Gravel encroachment caused by climate warming and glacial melting may alter community structure and community stability in alpine meadow. Yet, the effects of climate warming-induced gravel encroachment on grassland communities are unknown. Here, a 1-year short-term field experiment was conducted to explore the early stage drive process of gravel encroachment on community structure and stability at four different gravel encroachment levels 0%, 30%, 60%, and 90% gravel coverage at an alpine meadow on the Qinghai Tibetan Plateau, by analyzing the changes of dominant species stability and species asynchrony to the simulated gravel encroachment processes. Gravel encroachment rapidly changed the species composition and species ranking of alpine meadow plant community in a short period of time. Specifically, community stability of alpine meadow decreased by 61.78-79.48%, which may be due to the reduced dominant species stability and species asynchrony. Species asynchrony and dominant species stability were reduced by 2.65-17.39% and 46.51-67.97%, respectively. The results of this study demonstrate that gravel encroachment presents a severe negative impact on community structure and stability of alpine meadow in the short term, the longer term and comprehensive study should be conducted to accurate prediction of global warming-induced indirect effects on alpine grassland ecosystems.
社区稳定性是抵御和适应气候变化的主要能力。在全球气候变暖、冰川消融的世界中，高山砾石入侵普遍发生，威胁着山坡草地生态系统。气候变暖引起的冰川消融导致的砾石入侵可能会改变高寒草甸的群落结构和群落稳定性。然而，气候变暖诱导的砾石入侵对草原群落的影响尚不清楚。在这里，通过分析模拟砾石入侵过程中优势种稳定性和物种不同步性的变化，在青藏高原高寒草甸上进行了为期 1 年的短期野外实验，研究了砾石入侵对群落结构和稳定性的早期驱动过程。在很短的时间内，砾石入侵迅速改变了高寒草甸植物群落的物种组成和物种排名。具体来说，高寒草甸群落稳定性下降了 61.78%至 79.48%，这可能是由于优势种稳定性和物种不同步性降低所致。物种不同步性和优势种稳定性分别降低了 2.65%至 17.39%和 46.51%至 67.97%。本研究结果表明，砾石入侵在短期内对高寒草甸的群落结构和稳定性产生了严重的负面影响，应进行更长期和全面的研究，以准确预测全球变暖对高寒草地生态系统的间接影响。
