Chin J Plan Ecolo ›› 2018, Vol. 42 ›› Issue (8): 850-862.DOI: 10.17521/cjpe.2018.0068

• Research Articles • Previous Articles     Next Articles

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)

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