Characteristics of CO2 flux over the alpine wetland in the Tibetan Plateau and its control factors
Using the data observed by eddy-covariance flux in Longbao wetland,Yushu,in 2015,characteristcs of CO2 flux and its control factors were analyzed.The results show that daily change of CO2 flux in Longbao wetland was inverted unimodal and was negative in daylight and positive at night.Daily range of CO2 flux was maximum in July and minimum in January.From April to September there was a carbon sink in the alpine wetland ecosystem and a carbon source in other months.Annual CO2 net absorption was 465 g · m-2.CO2 flux decreased with photosynthetically active radiation increase in daylight.CO2 emission was positively correlated with soil temperature and daily rangeability of air temperature.Alpine wetland soil moisture effected on CO2 flux very weak.CO2 emission increased in short order after rain event.CO2 flux strongly correlated with photosynthetically active radiation,following by daily rangeability of air temperature and soil temperature.CO2 flux weakly correlated with soil moisture.
alpine wetlandCO2 fluxcarbon exchangeland surface process
NETL
NSTL
万方数据
维普
