title: [Effect of grazing on the temperature sensitivity of soil respiration in Hulunber meadow steppe].
abstract: Grazing is one of the major human activities which lead to disturbance on grassland ecosystem. Quantifying the effect of grazing on the temperature sensitivity of soil respiration ( Q10 ) is essential for accurate assessment of carbon budget in grassland ecosystem. This study was conducted on the grazing gradients experiment platform in Hulunber meadow steppe. Soil respiration was measured by a dynamic closed chamber method (equipped with Li 6400-09, Lincoln, NE, USA) during the growing season in 2011. The results showed that soil respiration had significant seasonal variation and the maximum occurred in July, which was mainly dominated by temperature. The order of average soil respiration during the period from May to September in different treatments was G1 > GO > G2 > G3 > G4 > G5. Comparing with non-grazing treatment, Q10 under heavy grazing conditions (0. 92 Au hm-2) was reduced by about 10% , and was increased a little under light grazing conditions (0. 23 Au hm-2). There was a significant negative correlation between Q15 and grazing intensities (r = 0. 944, P <0. 05) . Grazing could decrease the temperature sensitivity of soil respiration to different degrees. The Q10 under different grazing gradients had positive linear regression relationships with aboveground biomass, belowground biomass, soil organic carbon and soil moisture. They could explain 71.0%-85.2% variations of Q10. It was suggested that the variation of Q10 was mainly determined by the change of biotic and environmental factors due to grazing.
authors: Xu
authors: X
authors: Wang
authors: Rui-Rui
authors: RR
authors: Yan
authors: Yu
authors: Y
authors: Deng
authors: Yu-Chun
authors: YC
authors: Yan
authors: Xiao-Ping
authors: XP
authors: Xin
mesh_terms: D018533:Biomass; D002244:Carbon / Q000737:chemistry; D004784:Environmental Monitoring; D065948:Grassland; D060434:Herbivory; D006109:Poaceae; D012621:Seasons; D012987:Soil / Q000737:chemistry*; D013696:Temperature
chemical_list: D012987:Soil; D002244:Carbon