草地学报 ›› 2023, Vol. 31 ›› Issue (8): 2496-2504.DOI: 10.11733/j.issn.1007-0435.2023.08.028

• 研究论文 • 上一篇    下一篇

青海湖流域南岸温性草原CO2排放特征对模拟降雨变化的响应

李星玥1,2,3,4,5, 杜岩功6, 陈克龙1,2,3,4,5, 杨紫唯1,2,3,4,5   

  1. 1. 青海师范大学地理科学学院, 青海 西宁 810008;
    2. 青海省自然地理与环境过程重点实验室, 青海 西宁 810008;
    3. 青海师范大学青藏高原地表过程与生态保育教育部重点实验室, 青海 西宁 810008;
    4. 高原科学与可持续发展研究院, 青海 西宁 810008;
    5. 青海青海湖湿地生态系统国家定位观测研究站, 青海 海北 812200;
    6. 中国科学院西北高原生物研究所, 青海 西宁 810008
  • 收稿日期:2023-02-17 修回日期:2023-03-20 出版日期:2023-08-15 发布日期:2023-09-01
  • 通讯作者: 陈克龙,E-mail:ckl7813@163.com
  • 作者简介:李星玥(1998-),女,汉族,四川成都人,硕士研究生,主要从事自然地理与生态环境过程研究,E-mail:lixingyue0102@163.com
  • 基金资助:
    科技援青合作专项-青海湖入湖河流原位净化及河口湿地生态治理技术集成与示范(2022-QY-204);第二次青藏高原综合科学考察研究(2019QZKK0405)资助

Response of CO2 Emission Characteristics of Temperate Grasslands on the South Shore of Qinghai Lake Basin to Simulated Rainfall Changes

LI Xing-yue1,2,3,4,5, DU Yan-gong6, CHEN Ke-long1,2,3,4,5, YANG Zi-wei1,2,3,4,5   

  1. 1. College of Geographical Sciences, Qinghai Normal University, Xining, Qinghai Province 810008, China;
    2. Qinghai Province Key Laboratory of Physical Geography and Environmental Processes, Xining, Qinghai Province 810008, China;
    3. Key Laboratory of Ministry of Education for Surface Processes and Ecological Conservation of the Qinghai-Tibet Plateau, Qinghai Normal University, Xining, Qinghai Province 810008, China;
    4. Institute of Plateau Science and Sustainable Development, Xining, Qinghai Province 810008, China;
    5. National Station of Locating Observation and Research for Wetland Ecosystem in Qinghai Lake, Haibei, Qinghai Province 812200, China;
    6. Institute of Northwest Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai Province 810008, China
  • Received:2023-02-17 Revised:2023-03-20 Online:2023-08-15 Published:2023-09-01

摘要: 近20年,青海湖流域降雨量呈增加趋势。为准确揭示降雨变化对青海湖流域草地生态系统温性草原CO2排放速率的影响及调控因素,本研究以温性草原为研究对象,原位监测不同降雨处理下CO2排放特征,基于主成分和回归模型分析,解析CO2排放特征的主要调控因素。研究结果表明生长季5—8月各降雨处理下温性草原CO2基本为排放状态。5—8月五种实验处理下草地CO2平均排放速率之和的顺序为J25>Z75>CK>Z25>J75。增雨控制下CO2排放为自然对照的-3.53%~65.64%,减雨控制下CO2排放为自然对照的-33.35%~83.85%。降雨变化显著影响土壤湿度、生物量及土壤理化性质,雨季未到时CO2排放主要靠根系呼吸,雨季来临时土壤湿度对CO2排放影响显著高于土壤温度。并通过逐步回归分析法将影响因子进行逐步筛选,建立与CO2排放速率之间的回归方程模型,与各影响因子同CO2排放速率的相关分析相互印证,这对未来青海湖流域暖湿化背景下的温性草原CO2排放速率提供了参考。

关键词: 青海湖流域, 温性草原, 不同降雨处理, CO2排放速率

Abstract: In the past 20 years,rainfall in the Qinghai Lake basin has been increasing. In order to reveal the effects of rainfall changes on the CO2 emission rate of temperate grasslands in Qinghai Lake basin and the regulating factors,this study took that temperate grasslands as the research object,monitored the CO2 emission characteristics under different rainfall treatments in situ,and analyzed the main regulating factors of CO2 emission characteristics based on principal component and regression model analysis. The results showed that the CO2 emission of temperate grassland was basically in the state of emission under each rainfall treatment from May to August of the growing season. The order of the sum of the mean CO2 emission rates of grasses under the five experimental treatments from May to August was J25>Z75>CK>Z25>J75. CO2 emissions under rainfall increase control ranged from -3.53% to 65.64% of the natural control and -33.35% to 83.85% of the natural control under rainfall reduction control. Rainfall variation significantly affected soil moisture,biomass and soil physicochemical properties,and CO2 emission was mainly based on root respiration before the rainy season,while the effect of soil moisture on CO2 emission was significantly higher than that of soil temperature at the onset of the rainy season. The regression equation model between the influencing factors and CO2 emission rate was established by stepwise regression analysis,and the correlation analysis between the influencing factors and CO2 emission rate was corroborated,which provides a reference for the future CO2 emission rate of temperate grassland under the background of warming and humidification in Qinghai Lake basin.

Key words: Qinghai Lake Basin, Temperate grassland, Different precipitation treatments, CO2 emission rate

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