生物多样性 ›› 2023, Vol. 31 ›› Issue (3): 22118.  DOI: 10.17520/biods.2022118

• 研究报告: 植物多样性 •    下一篇

黄土高原典型草原植物群落组成对降水变化的响应

周欣扬, 王誉陶, 李建平()   

  1. 宁夏大学农学院, 银川 750021
  • 收稿日期:2022-03-18 接受日期:2022-08-21 出版日期:2023-03-20 发布日期:2022-09-21
  • 通讯作者: 李建平
  • 作者简介:* E-mail: lijianpingsas@163.com
  • 基金资助:
    国家自然科学基金(32160336);宁夏重点研发计划项目(2020BEG03046);宁夏大学草学一流学科建设项目(NXYLXK2017A01)

Response of plant community composition to precipitation changes in typical grasslands in the Loess Plateau

Xinyang Zhou, Yutao Wang, Jianping Li()   

  1. School of Agriculture, Ningxia University, Yinchuan 750021
  • Received:2022-03-18 Accepted:2022-08-21 Online:2023-03-20 Published:2022-09-21
  • Contact: Jianping Li

摘要:

探讨典型草原植物群落组成对降水变化的响应动态, 可为草地管理应对全球变化提供理论和实践依据。本研究以黄土高原腹地宁夏固原云雾山封育20年的典型草原为研究对象(模拟降水实验进行4年), 利用遮雨棚模拟3个不同的降水梯度, 分别是自然降水量的50% (PR)、100% (CK)和150% (PI), 每个降水梯度设置3个生物学重复。通过记录样地内植物的高度、频度、多度、密度和生物量, 定量分析了降水量的变化对典型草原植物群落物种多样性和生物量的影响。结果表明: (1)植物功能群对不同降水处理的响应差异显著, 与CK相比, 豆科植物总生物量在PR和PI处理下分别降低了42.72%和11.81%, 杂类草总生物量分别降低了74.49%和30.42%, 而禾本科植物总生物量分别增加了26.71%和97.06%。(2)降水变化对物种丰富度(P < 0.05)、Shannon-Wiener指数(P < 0.05)、Simpson指数(P < 0.01)均有显著或极显著影响。降水变化在一定程度上改变了植物群落物种丰富度和优势度, 导致植物群落结构发生变化, 从而改变植物群落组成。(3)随降水量增加, 优势种星毛委陵菜(Potentilla acaulis)的总体生物量呈增加趋势; 降水变化对长芒草(Stipa bungeana)、白莲蒿(Artemisia stechmanniana)的总体生物量影响不显著。研究结果将为进一步探究气候变化对典型草原生态系统的影响提供理论依据和数据支持。

关键词: 降水变化, 物种多样性, 植物群落组成, 生物量, 典型草原

Abstract

Aim: We explored the response dynamics of typical grassland plant community composition to precipitation changes to provide a theoretical and practical basis for grassland management to cope with global changes.

Methods: We carried out a 4-year simulated precipitation experiment in a 20-year enclosure grassland in the Loess Plateau. Three different precipitation gradients, 50% (PR), 100% (CK), and 150% (PI) of natural precipitation, were simulated using the canopy, with three biological replicates each. We measured vegetation height, frequency, abundance, density, and biomass in the sample plots. The impact of changes in precipitation on the species diversity and biomass of typical grassland plant communities was quantitatively analyzed.

Results: (1) We detected significant differences in the responses of vegetation functional groups to precipitation treatments. Compared with CK, the total biomass of legumes and weeds decreased in PR and PI, and legumes decreased by 42.72% and 11.81% in PR and PI, respectively; weeds decreased by 74.49% and 30.42% in PR and PI, respectively, while the total biomass of grasses increased by 26.71% and 97.06% in PR and PI, respectively. (2) Changes in rainfall had significant effects on species richness as well as the Shannon-Wiener index and Simpson index. The intuitive expression is that the structure of the plant community will change, thereby changing the composition of the plants in the plant community. (3) The increase in precipitation had a positive correlation with the biomass of the dominant plant Potentilla acaulis. Changes in precipitation had no significant effect on the total biomass of Stipa bungeana and Artemisia stechmanniana.

Conclusion: Precipitation changes can influence α diversity index of communities and the biomass of dominant species. Our results provide a theoretical basis for further exploring the impact of climate change on typical grassland ecosystems.

Key words: precipitation changes, species diversity, plant community composition, biomass, typical grassland