Methane and carbon dioxide emissions from 40 lakes along a north–south latitudinal transect in Alaska
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Published:2015-06-02
Issue:11
Volume:12
Page:3197-3223
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ISSN:1726-4189
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Container-title:Biogeosciences
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language:en
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Short-container-title:Biogeosciences
Author:
Sepulveda-Jauregui A.ORCID, Walter Anthony K. M., Martinez-Cruz K., Greene S., Thalasso F.
Abstract
Abstract. Uncertainties in the magnitude and seasonality of various gas emission modes, particularly among different lake types, limit our ability to estimate methane (CH4) and carbon dioxide (CO2) emissions from northern lakes. Here we assessed the relationship between CH4 and CO2 emission modes in 40 lakes along a latitudinal transect in Alaska to lakes' physicochemical properties and geographic characteristics, including permafrost soil type surrounding lakes. Emission modes included direct ebullition, diffusion, storage flux, and a newly identified ice-bubble storage (IBS) flux. We found that all lakes were net sources of atmospheric CH4 and CO2, but the climate warming impact of lake CH4 emissions was 2 times higher than that of CO2. Ebullition and diffusion were the dominant modes of CH4 and CO2 emissions, respectively. IBS, ~10% of total annual CH4 emissions, is the release to the atmosphere of seasonally ice-trapped bubbles when lake ice confining bubbles begins to melt in spring. IBS, which has not been explicitly accounted for in regional studies, increased the estimate of springtime emissions from our study lakes by 320%. Geographically, CH4 emissions from stratified, mixotrophic interior Alaska thermokarst (thaw) lakes formed in icy, organic-rich yedoma permafrost soils were 6-fold higher than from non-yedoma lakes throughout the rest of Alaska. The relationship between CO2 emissions and geographic parameters was weak, suggesting high variability among sources and sinks that regulate CO2 emissions (e.g., catchment waters, pH equilibrium). Total CH4 emission was correlated with concentrations of soluble reactive phosphorus and total nitrogen in lake water, Secchi depth, and lake area, with yedoma lakes having higher nutrient concentrations, shallower Secchi depth, and smaller lake areas. Our findings suggest that permafrost type plays important roles in determining CH4 emissions from lakes by both supplying organic matter to methanogenesis directly from thawing permafrost and by enhancing nutrient availability to primary production, which can also fuel decomposition and methanogenesis.
Funder
U.S. Department of Energy National Science Foundation National Aeronautics and Space Administration U.S. Geological Survey
Publisher
Copernicus GmbH
Subject
Earth-Surface Processes,Ecology, Evolution, Behavior and Systematics
Reference91 articles.
1. Abril, G., Guerin, F., Richard, S., Delmas, R., Galy-Lacaux, C., Gosse, P., Tremblay, A., Varfalvy, L., Dos Santos, M. A., and Matvienko, B.: Carbon dioxide and methane emissions and the carbon budget of a 10-year old tropical reservoir (Petit Saut, French Guiana), Global Biogeochem. Cy., 19, G02024, https://doi.org/10.1029/2007JG000608, 2005. 2. Arp, C. D. and Jones, B. M.: Geography of Alaska lake districts: Identification, description, and analysis of lake-rich regions of a diverse and dynamic state: US Geological Survey Scientific Investigations Report in: U.S.G.S.S.I., Gibbs, B., Fabian-Marks, J., Richey, B. J., Rogers, L., Richey, B. J., and Wahlstrom, S., USA, 2008–5215, 1–40, 2009. 3. Arp, C. D., Jones, B. M., and Grosse, G.: Recent lake ice-out phenology within and among lake districts of Alaska, USA, Limnol. and Oceanogr., 58, 2013–2028, 2013. 4. Bastviken, D., Ejlertsson, J., and Tranvik, L.: Measurement of Methane Oxidation in Lakes: A Comparison of Methods, Environ. Sci. Technol., 36, 3354–3361, 2002. 5. Bastviken, D., Cole, J., Pace, M., and Tranvik, L.: Methane emissions from lakes: Dependence of lake characteristics, two regional assessments, and a global estimate, Global Biogeochem. Cy., 18, GB4009, https://doi.org/10.1029/2004GB002238, 2004.
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