|DENG Huanguang,ZHANG Zhibo,LIU Tao,YIN Shanhong,DONG Jie,ZHANG Ju,YAO Xin.Dissolved greenhouse gas concentrations and the influencing factors in different vegetation zones of an urban lake. J. Lake Sci.2019,31(4):1055-1063. DOI:10.18307/2019.0409
|关键词: 温室气体 溶存浓度 影响因素 水生植被 城市湖泊 铃铛湖
|Dissolved greenhouse gas concentrations and the influencing factors in different vegetation zones of an urban lake
DENG Huanguang, ZHANG Zhibo, LIU Tao, YIN Shanhong, DONG Jie, ZHANG Ju, YAO Xin
School of Environment and Planning, Liaocheng University, Liaocheng 252000, P. R. China
|Dissolved concentrations of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) in the surface water were measured using the headspace equilibrium method fortnightly from April to November of 2015 in the Potamogeton crispus zone, Nymhaea tetragona zone and Nelumbo nucifera zone of the Lake Lingdang in Liaocheng City. The saturations and emission fluxes of the greenhouse gases were calculated based on the two-layered diffusion model. Moreover, water temperature, pH, dissolved oxygen (DO), chlorophyll-a and the nutrient concentrations in the water body were also measured in order to investigate their influences on the dissolved greenhouse gas concentrations. The results showed that the dissolved concentrations of greenhouse gases in different vegetation zones were all supersaturated, which indicated that Lake Lingdang was a source of atmospheric greenhouse gases. The concentrations, saturations and emission fluxes of CH4 in N. nucifera zone were significantly higher than those in P. crispus zone but no significant difference between the data of N2O and CO2 in different vegetation zones. The concentrations of DO, total nitrogen (TN), total phosphorus (TP) and nitrate (NO3--N) in three vegetation type zones also had significant differences. The average concentrations of DO, TN and NO3--N were highest in the P. crispus zone and lowest in the N. nucifera zone, but it was on the contrary for the average TP concentrations. The results of correlation analysis and multivariate regression analysis between the greenhouse gases and the water environment parameters suggested that the aquatic plants could affect the production and emission of greenhouse gases by influencing the physicochemical properties of water body. Greenhouse gas concentrations in lake water were mainly correlated to NO2--N, NO3--N, water temperature and DO in the P. crispus zone, while mainly correlated to TP and pH in the N. tetragona zone, and pH, NO2--N and DO in the N. nucifera zone.
|Key words: Greenhouse gas dissolved concentration influencing factor aquatic vegetation urban lake Lake Lingdang