[Responses of soil temperature in wetland ecosystem to air temperature and their effects on CO2 emission].
Through two years located field observation, this paper studied the responses of marsh soil temperature to air temperature and the effects of soil temperature on CO2 emission from marsh soil-vegetation system, and calculated the seasonal variation of CO2 emission. The results showed that from the beginning of thawing, an increasing trend of soil temperature was exerted by the change of air temperature, and there was a significant exponential correlation between soil temperature in root layer and air temperature (R2 = 0.94, P<0.01). Despite of the decreased responses of soil temperature to air temperature with increasing soil depth, the CO2 emission from marsh soil-vegetation system was strongly exponentially correlated with soil temperature in root layer (R2 = 0.84, P< 0.01). An improved model equation was used for calculating the mean CO2 efflux from marsh soil-vegetation system during the growth season in 2003, and the calculated CO2 efflux was 664.5 +/- 213.9 mg2 m(-2) h(-1), approaching the value of located field observation (634.0 +/- 227.7 mg x m(-2) h(-1)), indicating that this model equation was effective to evaluate the CO2 emission from marsh during growth season.
Song
Changchun
C
Northeast Institute of Geography and Agricultural Ecology, Chinese Academy of Sciences, Changchun 130012, China. songcc@neigae.ac.cn
Wang
Yiyon
Y
D000388:Air / Q000032:analysis*; D002245:Carbon Dioxide / Q000032:analysis*; D002980:Climate; D017753:Ecosystem; D018521:Plant Physiological Phenomena; D012987:Soil / Q000032:analysis*; D013696:Temperature
D012987:Soil; D002245:Carbon Dioxide