Carbon Dioxide in Soil and Surface Waters in the North of Western Siberia: Methodological Approach and Quantitative

Abstract

Dissolved inorganic carbon is an essential component of the carbon cycle, especially in the northern regions, while its loss through water bodies is still rarely included in regional carbon models. The tasks of the work included a detailed coverage of the methodological approach “headspace equilibration” to the study of the concentration of dissolved CO₂in soil and surface waters, as well as the assessment of the range of CO₂concentrations in waters of different genesis in the landscapes of the north of Western Siberia. As a result of the methodological work done, a protocol was developed and presented for measuring the concentration of CO₂in waters by the “headspace equilibration” method with detailed calculations. The concentration of CO₂ in soil (supra-permafrost) and surface waters (river, bog, lake, etc.) ranged from 13 to 2983 µmol/l (274 to 57000 µatm), the vast majority of objects were supersaturated with CO₂ relative to the atmosphere. The maximum values of concentrations are characterized by supra-permafrost soil and bog waters; the minimum is the waters of aquatic ecosystems: thermokarst and forest lakes. The high variability of CO₂concentration in waters necessitates a large number of measurements to obtain adequate estimates.