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Title: Lake Morphometry and River Network Controls on Evasion of Terrestrially Sourced Headwater CO 2

Lakes are central components of the inland water system distinct from, yet inextricably connected to, river networks. Currently, existing network‐scale biogeochemistry research, although robust, typically treats each of these components separately or reductively. Here, we incorporate lake morphometry into a fully connected stream/lake network for the Connecticut River watershed and model potential evasion of terrestrially sourced headwater CO2as transported through the network, ignoring in‐stream production. We found that approximately 25%–30% of total potential soil CO2evasion occurs in lakes, and percent evasion is inversely related to streamflow. A lake's ability to evade CO2is controlled by residence time and size: most lakes with residence time over 7 days or surface area greater than 0.004 km2evade functionally all terrestrial CO2entering from upstream, precluding further downstream transport. We conclude that lakes are important for soil CO2degassing and that this coupled river/lake approach is promising for CO2studies henceforth.

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DOI PREFIX: 10.1029
Date Published:
Journal Name:
Geophysical Research Letters
Medium: X
Sponsoring Org:
National Science Foundation
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