Greenhouse gases emission from the sewage draining rivers

Beibei Hu; Dongqi Wang; Jun Zhou; Weiqing Meng; Chongwei Li; Zongbin Sun; Xin Guo; Zhongliang Wang

doi:10.1016/j.scitotenv.2017.08.055

Greenhouse gases emission from the sewage draining rivers

Sci Total Environ. 2018 Jan 15:612:1454-1462. doi: 10.1016/j.scitotenv.2017.08.055. Epub 2017 Sep 25.

Authors

Beibei Hu¹, Dongqi Wang², Jun Zhou¹, Weiqing Meng³, Chongwei Li¹, Zongbin Sun⁴, Xin Guo⁴, Zhongliang Wang¹

Affiliations

¹ School of Geographic and Environmental Sciences, Tianjin Normal University, Tianjin 300387, China; Tianjin Key Laboratory of Water Resources and Environment, Tianjin Normal University, Tianjin 300387, China.
² Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai 200241, China; School of Geographic Sciences, East China Normal University, Shanghai 200241, China.
³ School of Geographic and Environmental Sciences, Tianjin Normal University, Tianjin 300387, China; Tianjin Key Laboratory of Water Resources and Environment, Tianjin Normal University, Tianjin 300387, China. Electronic address: mengweiqing@mail.nankai.edu.cn.
⁴ School of Geographic and Environmental Sciences, Tianjin Normal University, Tianjin 300387, China.

PMID: 28903174
DOI: 10.1016/j.scitotenv.2017.08.055

Abstract

Carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O) concentration, saturation and fluxes in rivers (Beitang drainage river, Dagu drainage rive, Duliujianhe river, Yongdingxinhe river and Nanyunhe river) of Tianjin city (Haihe watershed) were investigated during July and October in 2014, and January and April in 2015 by static headspace gas chromatography method and the two-layer model of diffusive gas exchange. The influence of environmental variables on greenhouse gases (GHGs) concentration under the disturbance of anthropogenic activities was discussed by Spearman correlative analysis and multiple stepwise regression analysis. The results showed that the concentration and fluxes of CO₂, CH₄ and N₂O were seasonally variable with >winter>fall>summer, spring>summer>winter>fall and summer>spring>winter>fall for concentrations and spring>summer>fall>winter, spring>summer>winter>fall and summer>spring>fall>winter for fluxes respectively. The GHGs concentration and saturation were higher in comprehensively polluted river sites and lower in lightly polluted river sites. The three GHGs emission fluxes in two sewage draining rivers of Tianjin were clearly higher than those of other rivers (natural rivers) and the spatial variation of CH₄ was more obvious than the others. CO₂ and N₂O air-water interface emission fluxes of the sewage draining rivers in four seasons were about 1.20-2.41 times and 1.13-3.12 times of those in the natural rivers. The CH₄ emission fluxes of the sewage draining rivers were 3.09 times in fall to 10.87 times in spring of those in the natural rivers in different season. The wind speed, water temperature and air temperature were related to GHGs concentrations. Nitrate and nitrite (NO₃^-+NO₂^--N) and ammonia (NH₄⁺-N) were positively correlated with CO₂ concentration and CH₄ concentration; and dissolved oxygen (DO) concentration was negatively correlated with CH₄ concentration and N₂O concentration. The effect of human activities on carbon and nitrogen cycling in river is great.

Keywords: Dissolved concentration; Emission flux; Greenhouse gas; Influencing factors; Sewage draining rivers; Tianjin.

MeSH terms

Carbon Cycle
Carbon Dioxide / analysis
China
Environmental Monitoring*
Greenhouse Effect
Greenhouse Gases / analysis*
Methane / analysis
Nitrogen Cycle
Nitrous Oxide / analysis
Rivers / chemistry*
Seasons
Sewage / chemistry*

Substances

Greenhouse Gases
Sewage
Carbon Dioxide
Nitrous Oxide
Methane