摘要
以深圳坝光湿地园为研究对象,选取沟渠、池塘、河口 3种水体,开展为期1a的野外监测,探究高度城市化小型水体中温室气体的时空特征及驱动因素.结果表明:水体中 CO2、CH4、N2O 溶存浓度平均值为(54.30±49.55)、(0.89±1.45)、(0.0038±0.0007)μmol/L,通量的平均值为(113.94±424.19)、(1.48±3.84)、(0.0044±0.0176)mg/(m2·h),是大气温室气体排放源.其中,CO2的排放潜力远超过滨海水域、湖泊等水体,是在整个湿地园水体的全球增温潜势的主要贡献者,占比高达85.87％.在时空上,温室气体的浓度和通量主要表现为暖季(8月)＞冷季(1、4、12月),沟渠＞池塘、河口,且靠近湿地园中部更高.盐度、pH值、氨态氮、硝态氮、电导率、化学需氧量和总有机碳是影响水体中温室气体溶存浓度差异的关键环境因子,而电导率是影响通量变化的主要环境因子.
Abstract
This study selected Shenzhen Baguang wetland park as the study area.A one-year sampling program was conducted within three types of water bodies,i.e.,ditches,ponds and estuaries.Measured data were used to investigate the seasonal and spatial pattern of greenhouse gas and its driving factors in the typical small water body within highly urbanized area.The results showed that the average concentrations of dissolved CO2,CH4,and N2O in the water were(54.30±49.55),(0.89±1.45),and(0.0038±0.0007)μmol/L,respectively.The average fluxes of CO2,CH4,and N2O emission were(113.94±424.19),(1.48±3.84),and(0.0044±0.0176)mg/(m2·h),respectively,implying a source of greenhouse gas to atmosphere.The emission potential of CO2 from these small water bodies was much higher than coastal waters,lakes and other waters,and was the main contributor(85.57％)to the global warming within the entire wetland park water.From the perspective of spatial and temporal heterogeneity,greenhouse gas concentrations and fluxes showed a pattern of warm season(August)＞cool season(January,April,December),ditches＞ponds and estuaries,and were higher near the middle of the wetland park.Salinity,pH,ammonium nitrogen,nitrate,electrical conductivity,chemical oxygen demand,and total organic carbon were the critical environmental factors contributing to differences in dissolved greenhouse gas concentrations in the water.EC was the critical environmental factor influencing greenhouse gas fluxes.
基金项目
广东省基础与应用基础研究基金项目(2021A1515011670)
国家自然科学青年基金项目(42201076)
广东省林业科技创新项目(2021KJCX005)
维普
万方数据