CSpace  > 生态水文研究中心
Biotic and abiotic controls on CO2 partial pressure and CO2 emission in the Tigris River, Turkey
Varol, Memet1; Li, Siyue2
2017-01-20
摘要Rivers act not only as vectors from the terrestrial biosphere to the ocean but also as significant sources of CO2 to the atmosphere, which plays a key role in the global carbon cycle. In this study, dissolved inorganic carbon (DIC) and carbon dioxide partial pressure (pCO(2)) in the Tigris River were investigated. The alkalinity concentrations of the Tigris River ranged from 1718 to 4995 mu q/L with an average of 3064 mu q/L (median: 2877 mu eq/L), 23 times the global median value of 1256 mu eq/L Higher alkalinity values occurred in autumn and winter months that were due to carbonate rock weathering, pCO(2) values varied from 95.6 to 16,001.8 mu atm with a total average of 1277 +/- 1883 mu atm. >80% of samples had pCO(2) above atmospheric equilibrium (390 mu atm). The highest levels of pCO(2) occurred at stations Diyarbakir, Bismil and Cizre, which are categorized as polluted stations. The lowest levels of pCO(2) generally occurred in the wet season (October-April) due to dilution effect of rainfall. The estimated water-to-air CO2 degassing flux from the Tigris River was around 39 mol/m(2)/y. Thus, 0.15 Tg C/y as CO2 released from the river to the atmosphere, about 0.6 fold the riverine DIC flux (0.25 Tg C/y). Correlative analyses demonstrated that population density and air temperature increased pCO(2), while slope degree decreased pCO(2). pCO(2) also had positive correlations with COD, NH4-N, PO4-P, SO4, Cl, phytoplankton abundance and number of phytoplankton taxa, while negative correlations with DO saturation and pH. (C) 2016 Elsevier B.V. All rights reserved.
关键词Riverine carbon flux CO2 degassing Partial pressure of CO2 (pCO(2)) Dissolved inorganic carbon Biotic and abiotic factors Tigris River
DOI10.1016/j.chemgeo.2016.12.003
发表期刊CHEMICAL GEOLOGY
ISSN0009-2541
卷号449页码:182-193
收录类别SCI
WOS记录号WOS:000393001800015
语种英语