研究报告
洪妍,张逸飞,杨平,仝川,YANG Hong,唐晨.闽江河口区文武砂水库水体溶存CH4浓度时空变化特征[J].环境科学学报,2022,42(5):304-313
闽江河口区文武砂水库水体溶存CH4浓度时空变化特征
- Spatiotemporal variations in dissolved CH4 concentration in Wenwusha Reservoir from Min River Estuary, southeast China
- 基金项目:国家自然科学基金(No.41801070,41671088);福建省科技厅自然科学基金面上项目(No.2020J01136);福建省教育厅中青年教师 教育科研项目(No.JT180065,JT180066)
- 张逸飞
- 福建师范大学地理科学学院,福州 350007
- 杨平
- 福建师范大学地理科学学院,福州 350007;湿润亚热带生态-地理过程教育部重点实验室,福州 350007;福建师范大学亚热带湿地研究中心,福州 350007
- 仝川
- 福建师范大学地理科学学院,福州 350007;湿润亚热带生态-地理过程教育部重点实验室,福州 350007;福建师范大学亚热带湿地研究中心,福州 350007
- YANG Hong
- Department of Geography and Environmental Science, University of Reading, Reading, RG6 6AB, UK
- 摘要:甲烷(CH4)是一种重要的温室气体,在全球气候变化中扮演着重要角色.水库作为大气库中CH4的重要来源而备受关注.为探究亚热带河口区水库溶存CH4浓度时空变化特征及其影响因素,于2018年11月(秋季)、2019年3月(春季)和6月(夏季)分别对文武砂水库表层水进行高精度多空间点位采样分析.结果表明,文武砂水库表层水体CH4浓度在研究期间的变化范围为0.03~27.35 μmol·L-1,呈现春、夏季显著高于秋季的时间变化特征(p<0.01);在空间变化上,外源输入强度大的库区水体溶存CH4浓度显著较高,且呈现出由库区沿海区向中心区递减的 趋势.相关分析结果显示,水库表层水体CH4浓度与水温、DOC浓度呈显著正相关关系(p<0.05或p <0.01),与水体盐度和溶解氧呈显著负相关关系(p<0.01).本研究结果证实亚热带水库是一个重要的CH4排放源,库区周边的废水排入等因素影响了CH4的排放.
- Abstract:CH4 is an important greenhouse gas in the atmosphere, which plays an important role in global climate change. Some preliminary studies suggest that reservoirs are potentially significant contributors to global CH4 emissions, and therefore there are increasing concerns about CH4 emissions from reservoirs in recent decades. To explore the spatiotemporal variations and influence factors of dissolved CH4 in subtropical coastal reservoirs, we conducted high-resolution sampling of dissolved CH4 and related hydrographical parameters in the surface water in Wenwusha Reservoir in southeastern China in November 2018 (Autumn), March 2019 (Spring) and June 2019 (Summer). Our results showed that the dissolved CH4 concentrations of the surface water of Wenwusha Reservoir during the study period changed in the range of 0.03~27.35 μmol·L-1. Temporally, the mean dissolved CH4 concentrations in spring and summer were significantly higher than those in the autumn (p<0.01). Spatially, the dissolved CH4 concentrations in the zone with sewage loading and river input were higher than those in the other zones. Furthermore, the dissolved CH4 concentrations decreased along a gradient from the littoral area to the central area of the reservoir. The Spearman correlation analysis showed that the CH4 concentrations in surface water of the reservoir was positively correlated with water temperature (p<0.05) and DOC (p<0.01), and negatively correlated with salinity and dissolved oxygen (p<0.01). Our findings confirm that subtropical reservoirs are important CH4 sources and sewage input from the catchment and other factors influence CH4 emissions.