欢迎访问《草业学报》官方网站,今天是 分享到:

草业学报 ›› 2021, Vol. 30 ›› Issue (2): 82-92.DOI: 10.11686/cyxb2020099

• 研究论文 • 上一篇    下一篇

模拟干旱对藏北高寒草甸植物物候期和生产力的影响

罗文蓉1(), 胡国铮1(), 干珠扎布1, 高清竹1, 李岩1, 葛怡情2, 李钰3, 何世丞4, 旦久罗布4   

  1. 1.中国农业科学院农业环境与可持续发展研究所,农业部农业环境与气候变化重点实验室,北京 100081
    2.内蒙古大学生态与环境学院,内蒙古 呼和浩特 010021
    3.北京师范大学环境学院,北京 100875
    4.西藏自治区那曲地区草原站,西藏 那曲 852100
  • 收稿日期:2020-03-07 修回日期:2020-04-27 出版日期:2021-02-20 发布日期:2021-01-19
  • 通讯作者: 胡国铮
  • 作者简介:E-mail: huguozheng@caas.cn
    罗文蓉(1992-),女,贵州龙里人,硕士。E-mail: luowenrong1201@sina.com
  • 基金资助:
    第二次青藏高原综合考察研究(2019QZKK0307);国家重点研发计划课题(2016YFC0502003);国家自然科学基金项目(31800383);国家自然科学基金项目(31570484);中央级公益性科研院所基本科研业务费专项资金(20290-2017);西藏那曲地区与中国农业科学院合作项目资助

Effects of simulated drought on plant phenology and productivity in an alpine meadow in Northern Tibet

Wen-rong LUO1(), Guo-zheng HU1(), Ganjurjav H1, Qing-zhu GAO1, Yan LI1, Yi-qing Ge2, Yu LI3, Shi-cheng HE4, Luo-bu DANJIU4   

  1. 1.Institute of Environment and Sustainable Development in Agriculture,Chinese Academy of Agricultural Sciences,Key Laboratory for Agro-Environment & Climate Change,Ministry of Agriculture,Beijing 100081,China
    2.College of Ecology and Environment,Inner Mongolia University,Hohhot 010021,China
    3.School of Environmental Science,Beijing Normal University,Beijing 100875,China
    4.Nagqu Grassland Station,Tibet,Nagqu 852100,China
  • Received:2020-03-07 Revised:2020-04-27 Online:2021-02-20 Published:2021-01-19
  • Contact: Guo-zheng HU

摘要:

为探究生长季不同时期干旱事件对高寒草甸植物物候期和生产力的影响,采用截雨棚于藏北高寒草甸生长季前期和后期进行为期2年(2016-2017年)的截雨试验。结果表明:1)植物物候期对不同时期干旱处理响应不同,高寒草甸关键物种植物物候期对生长季前期干旱(SE)响应较为敏感,SE会导致植物返青期大幅推迟,生长季长度和繁殖期明显缩短(P<0.05),而生长季后期干旱(SL)对植物物候期无显著影响;2)群落和各功能类群的生物量在不同时期干旱处理下均显著降低,总生物量较对照样地下降幅度最大,达62.9%(P<0.05),群落高度和盖度受到干旱不同程度的抑制,而不同功能类群的响应存在差异;3)群落高度、生物量与生长季长度和繁殖期均呈显著正相关(P<0.05)。表明高寒草甸植被生产力对干旱的响应受物候期的调控,物候期主要通过影响植株高度调控群落生产力,而不同功能类群植物对干旱事件的差异化响应,指示着干旱事件增多和加剧将导致高寒草甸植被群落结构的改变。

关键词: 藏北地区, 高寒草甸, 干旱事件, 物候期, 生产力

Abstract:

This research aimed to elucidate the effects of drought events on the phenology and productivity of the plant community in Tibetan alpine meadow. A rainfall interception experiment comprising drought treatments imposed early or late in the growing season (SE and SL, respectively) was carried out in alpine meadow of Northern Tibet, over two years (2016-2017). Results showed that: 1) The plant phenology had a contrasting response to SE and SL drought treatments. Plant phenology of key species was more sensitive to SE. SE significantly delayed plant green update, and led to a shorter growing season and reproductive duration (P<0.05), while SL had no significant effect on plant phenology. 2) Biomass of the plant community and different functional groups decreased under the drought treatments. Community biomass decreased by 62.9% (P<0.05). The height and coverage of the community was suppressed by drought, while the response of height and coverage differed between grasses and forbs. 3) Community height and biomass were significantly positively correlated with the growing season and reproductive duration (P<0.05). The results indicate that the productivity of alpine meadow grassland was regulated by phenology in response to drought, mainly through the impact on plant height. Moreover, the responses to drought varied between different functional groups, and suggest that increasing and intensified drought may lead to change in the community structure of alpine meadow.

Key words: Northern Tibet, alpine meadow, drought events, phenological period, productivity