Chin J Plant Ecol ›› 2011, Vol. 35 ›› Issue (2): 167-175.DOI: 10.3724/SP.J.1258.2011.00167

• Research Articles • Previous Articles     Next Articles

Variations of soil respiration rate and its temperature sensitivity among different land use types in the agro-pastoral ecotone of Inner Mongolia

MA Jun1,2, TANG Hai-Ping1,2,*()   

  1. 1State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, China
    2College of Resources Science and Technology, Beijing Normal University, Beijing 100875, China
  • Received:2010-04-14 Accepted:2010-11-12 Online:2011-04-14 Published:2011-01-21
  • Contact: TANG Hai-Ping

Abstract:

Aims Our objectives are to compare soil respiration rate and its temperature sensitivity at different land use types and discuss soil respiration response to soil temperature (Ts) and soil water content at different soil depths.
Methods Periodic measurements of soil respiration rates (Rs) were made during August-October 2009 with a LI-8100 portable automated soil CO2 flux system in three agro-pastoral ecotone land use types: cropland, abandoned cultivated land and grazing enclosure. Soil temperature and soil water content at 0-5, 5-10 and 10-15 cm depths were measured simultaneous adjacent to the soil collar.
Important findings Rs is significantly different among the three land use types and greatest in cropland. Rs exhibited a unimodal curve during 6:00-18:00, with a maximum during 12:00-15:00. Rs decreased with Ts, so Rs was significantly higher in August than in September and October. With the Van’t Hoff model, we concluded there is a positive, exponential relationship between measured Ts and Rs. In addition, temperature sensitivity of soil respiration (Q10), which is derived from the Van’t Hoff model, was largest in cropland. In contrast, Rs was negatively related to soil water content in different soil depths at the sites.

Key words: Q10, soil respiration rate, soil temperature, soil water content