草地学报 ›› 2019, Vol. 27 ›› Issue (6): 1553-1561.DOI: 10.11733/j.issn.1007-0435.2019.06.012

• 研究论文 • 上一篇    下一篇

短期增温对长江源区高寒沼泽草甸植物-土壤C,N化学计量及季节变化特征的影响

刘永万, 白炜, 尹鹏松, 冯月, 张景然   

  1. 兰州交通大学环境与市政工程学院, 甘肃 兰州 730070
  • 收稿日期:2019-07-13 修回日期:2019-09-10 出版日期:2019-12-15 发布日期:2019-12-31
  • 通讯作者: 白炜,E-mail:baiwei915@163.com
  • 作者简介:刘永万(1995-),男,甘肃兰州人,硕士研究生,主要从事寒旱区气候变化研究,E-mail:lyw0616@163.com
  • 基金资助:
    国家自然科学基金(41563005,41877149);兰州交通大学青年科学基金(2015013)资助

Effects of Short-term Warming on the Stoichiometric Characteristics and Seasonal Variation of Plant-soil C and N in Alpine Swamp Meadows in the Headwaters Region of the Yangtze River

LIU Yong-wan, BAI Wei, YING Peng-song, Feng Yue, Zhang Jing-ran   

  1. Lanzhou Jiaotong University, School of Environmental and Municipal Engineering, Lanzhou, Gansu Province 730070, China
  • Received:2019-07-13 Revised:2019-09-10 Online:2019-12-15 Published:2019-12-31

摘要: 为了探讨植物-土壤C,N化学计量及其季节变化特征对气候变暖的响应特征和调控机制,本研究以风火山地区高寒沼泽草甸优势种藏嵩草(Kobresia tibetica)为研究对象,采用开顶式增温室(OTC)模拟气候变暖,对2种增温幅度条件下(T1:增温1.5~2.5℃;T2:增温3~5℃)植物-土壤碳(C)、氮(N)化学计量及其季节变化展开研究。结果表明:植物在不同增温幅度下对C、N的利用率不同;该研究区土壤处于氮限制状态,增温加剧了这种限制,植物通过提高养分重吸收率来应对自然胁迫;植物C,N含量与土壤C,N含量呈显著相关(P<0.05)或极显著相关(P<0.01)。研究认为:温度变化影响了沼泽草甸植被生长及其C,N含量,但不同季节对其影响并不一致;在养分供应上,整个生长季内增温和对照处理下植物生长均受N素限制。

关键词: 高寒沼泽草甸, 增温, 植物地上部分, 枯落物, 根系, 土壤

Abstract: To investigate the response mechanism of the plant-soil C and N stoichiometry and seasonal variation characteristics to climate warming in the alpine swamp meadow,open top chambers (OTC) were established to simulate global warming at Fenghuoshan site located in the hinterland of Qinghai-Tibetan Plateau,and the C and N stoichiometry of a dominant specie (Kobresia tibetica) and the surface soil in warming plots (T1,warming 1.5~2.5℃;T2,warming 3~5℃) were determined and analyzed. Results showed that:(1) Plants have different utilization rates of C and N under different warming treatments. (2) The soil in the study area was nitrogen-limited,and this nutrient limitation was exacerbated in warming plots,thus the plants responded to natural stress by increasing the reabsorption rate of nutrients. (3) Correlation analysis showed that plant C and N were significantly (P<0.05) or extremely significantly (P<0.01) correlated with soil C and N content. In conclusion,warming significantly affected the growth and C,N contents of plants in alpine swamp meadow,but the effects in different periods were not consistent. In addition,the shortage in N nutrient supply in warming (T1,T2) and CK plots was suggested to have caused the decreased growth of plants during the entire growing season.

Key words: Alpine swamp meadow, Warming, Shoots of plants, Litter, Roots, Soil

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