Chin J Plant Ecol ›› 2019, Vol. 43 ›› Issue (2): 152-164.DOI: 10.17521/cjpe.2017.0280

• Research Articles • Previous Articles     Next Articles

Effects of collar size and buried depth on the measurement of soil respiration in a typical steppe

LI Jian-Jun1,2,LIU Lian1,2,CHEN Di-Ma1,XU Feng-Wei1,2,CHENG Jun-Hui3,BAI Yong-Fei1,**()   

  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 College of Grassland and Environment Science, Xingjiang Agricultural University, ürümqi 830052, China;
  • Received:2017-11-02 Accepted:2018-04-19 Online:2019-02-20 Published:2019-06-04
  • Contact: BAI Yong-Fei
  • Supported by:
    Supported by the National Natural Science Foundation of China(31320103916);Supported by the National Natural Science Foundation of China(31630010)

Abstract: <i>Aims</i>

Soil respiration plays an important role in carbon cycling in grassland ecosystems. However, the effects of collar size and buried depth during field measurement on soil respiration are rarely assessed.

<i>Methods</i>

We conducted a two-factor experiment to examine how soil collar depth (2 cm and 5 cm) and size (15 cm × 15 cm and 30 cm × 30 cm) affected the soil respiration (SR), post aboveground net primary productivity (post-ANPP), soil temperature (ST), and soil water content (SWC) in a semi-arid steppe.

<i>Important findings</i>

The results showed that the deep-inserted soil collar (5 cm soil depth) decreased the soil respiration by 8.0%-9.7% compared with the shallow-inserted soil collar (2 cm soil depth). The large-sized soil collar (30 cm × 30 cm) decreased the soil respiration by 9.1%-10.8% compared with the small-sized soil collar (15 cm × 15 cm). We also found that the deep-inserted and large-sized soil collars had higher ST but lower SWC compared with the shallow-depth and small-sized soil collars. Structural equation model indicated that the lower respiration in the deep-inserted and large-sized soil collars was due to the lower post-ANPP, ST, and SWC. Overall, we found that the soil collar size and buried depth can substantially alter the magnitude of soil respiration by changing plant biomass, ST, and SWC. These findings suggest that the influences of collar size and buried depth on soil respiration should be considered for better estimation and modeling of soil CO2 fluxes in terrestrial ecosystems.

Key words: collar, net primary productivity, soil temperature, soil water content, clonal integration, seasonal dynamics, CO2, structural equation model