Issue 7, 2016

Landscape geomorphic characteristic impacts on greenhouse gas fluxes in exposed stream and riparian sediments

Abstract

While excessive releases of greenhouse gases (GHG: N2O, CO2, CH4) to the atmosphere due to the burning of fossil fuel remains a concern, we also need to better quantify GHG emissions from natural systems. This study investigates GHG fluxes at the soil–atmosphere interface in a series of 7 stream reaches (riparian zones + exposed streambed sediment) across a range of geomorphic locations from headwaters reaches to lowland wetland reaches. When riparian fluxes (RZ) are compared to fluxes from in-stream locations (IS) under summer baseflow conditions, total CO2-equivalent (CO2eq) emissions are approximately 5 times higher at RZ locations than at IS locations, with most CO2eq driven by CH4 production at RZ locations where wet conditions dominate (headwater wetlands, lowland wetlands). On a gas-by-gas basis, no clear differences in N2O fluxes between RZ and IS locations were observed regardless of locations (headwater vs. lowland reaches), while CO2 fluxes were significantly larger at RZ locations than IS locations. Methane fluxes were significantly higher in wetland-influenced reaches than other reaches for both RZ and IS locations. However, GHG fluxes were not consistently correlated to DOC, DO, NO3, NH4+, or water temperature, stressing the limitations of using water quality parameters to predict GHG emissions at the floodplain scale, at least during summer baseflow conditions. As strategies are developed to further constrain GHG emission for whole watersheds, we propose that approaches linking landscape geomorphic characteristics to GHG fluxes at the soil–atmosphere interface offer a promising avenue to successfully predict GHG emissions in floodplains at the watershed scale.

Graphical abstract: Landscape geomorphic characteristic impacts on greenhouse gas fluxes in exposed stream and riparian sediments

Article information

Article type
Paper
Submitted
15 मार्च 2016
Accepted
09 जून 2016
First published
09 जून 2016

Environ. Sci.: Processes Impacts, 2016,18, 844-853

Landscape geomorphic characteristic impacts on greenhouse gas fluxes in exposed stream and riparian sediments

P. Vidon and S. Serchan, Environ. Sci.: Processes Impacts, 2016, 18, 844 DOI: 10.1039/C6EM00162A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements