植物生态学报 ›› 2018, Vol. 42 ›› Issue (8): 850-862.DOI: 10.17521/cjpe.2018.0068

• 研究论文 • 上一篇    下一篇

半干旱草原土壤呼吸组分区分与菌根呼吸的贡献

李伟晶1,2,陈世苹1,*(),张兵伟1,3,谭星儒1,2,王珊珊1,2,游翠海1,2   

  1. 1 中国科学院植物研究所植被与环境变化国家重点实验室, 北京 100093
    2 中国科学院大学资源与环境学院, 北京 100049
    3 中山大学有害生物控制与资源利用国家重点实验室, 中山大学生命科学学院, 广州 510275
  • 收稿日期:2018-03-29 出版日期:2018-08-20 发布日期:2018-06-01
  • 通讯作者: 陈世苹
  • 基金资助:
    国家自然科学基金(41773084);国家重点研发计划(2017YFA0604801)

Partitioning of soil respiration components and evaluating the mycorrhizal contribution to soil respiration in a semiarid grassland

LI Wei-Jing1,2,CHEN Shi-Ping1,*(),ZHANG Bing-Wei1,3,TAN Xing-Ru1,2,WANG Shan-Shan1,2,YOU Cui-Hai1,2   

  1. 1 State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
    2 College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
    3 State Key Laboratory of Biocontrol and School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
  • Received:2018-03-29 Online:2018-08-20 Published:2018-06-01
  • Contact: Shi-Ping CHEN
  • Supported by:
    Supported by the National Natural Science Foundation of China(41773084);the National Program on Key Research Project of China(2017YFA0604801)

摘要:

土壤呼吸组分的区分对于理解地下碳循环过程非常重要。而菌根真菌在地下碳循环过程中扮演着重要的角色, 但是有关菌根呼吸在草原生态系统中的研究相对较少。该研究在内蒙古半干旱草原应用深浅环网孔法, 结合浅环、深环(排除根系)和一个带有40 μm孔径窗口的土壤环(排除根系但是有菌根菌丝体)将根和菌丝物理分离, 来区分不同的呼吸组分。结果表明: 异养呼吸对总呼吸的贡献比例为51%, 根呼吸的贡献比例为26%, 菌根呼吸的贡献比例为23%, 菌根呼吸的比例3年变化范围为21%-26%。与国内外研究相比, 此方法提供了一个相对稳定的菌根呼吸测量精度范围, 在草原生态系统中切实可行。对菌根呼吸的准确定量将有助于预测草原生态系统土壤碳释放过程对未来气候变化的响应。

关键词: 深浅环网孔法, 异养呼吸, 自养呼吸, 菌根呼吸, 半干旱草原

Abstract:

Aims Soil respiration component partitioning is pivotal to understand the belowground carbon (C) cycle. Mycorrhizal fungi have been proven to play an important role in the soil C turnover, but only a few studies have been conducted to quantify the contribution of mycorrhizal respiration to total soil respiration in grassland ecosystems.
Methods The mini-trenching mesh method was applied to partition soil respiration components of a semi-arid grassland in Inner Mongolia. A shallow collar (measuring soil total respiration), a deep collar (excluding roots and mycorrhizal hypahe) and a deep collar with 40 μm pore mesh window (excluding roots but not mycorrhizal hyphae) were installed in each plot. Soil respiration rate of each collar was measured every two weeks during the growing season from 2014 to 2016. The differences in the rate of soil respiration among different type of collars were used to partition the components of soil respiration.
Important findings The results showed that the contribution of heterotrophic, root and mycorrhizal respiration to total soil respiration was 49%, 28%, and 23%, respectively. Across the three years, the proportion of mycorrhizal respiration varied from 21%-26%, which is comparable with the results reported by other studies recently. Our results demonstrated that the mini-trenching mesh method is a suitable method for separating mycorrhizal respiration component in grassland ecosystems. Evaluating the contribution of mycorrhizal respiration to total soil respiration is very important for predicting the responses of soil carbon release to future climate change.

Key words: the mini-trenching mesh method, heterotrophic respiration, autotrophic respiration, mycorrhizal respiration, semiarid grassland