Inconsistent browning of northeastern U.S. lakes despite increased precipitation and recovery from acidification

Jean-Francois Lapierre; Sarah M. Collins; Samantha K. Oliver; Emily H. Stanley; Tyler Wagner

doi:10.1002/ecs2.3415

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USGS · 70222098

Inconsistent browning of northeastern U.S. lakes despite increased precipitation and recovery from acidification

Jean-Francois Lapierre·Sarah M. Collins·Samantha K. Oliver·Emily H. Stanley·Tyler Wagner

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Abstract

Multiple studies have reported widespread browning of Northern Hemisphere lakes. Most examples are from boreal lakes that have experienced limited human influence, and browning has alternatively been attributed to changes in atmospheric deposition, climate, and land use. To determine the extent and possible causes of browning across a more geographically diverse region, we examined watercolor and dissolved organic carbon (DOC) time series in hundreds of northeastern U.S. lakes. The majority of lakes have increased in both DOC and color, but there were neither coherent spatial patterns in trends nor relationships with previously reported drivers. Color trends were more variable than DOC trends, and DOC and color trends were not strongly correlated, indicating a cause other than or in addition to increased loading of terrestrial carbon. Browning may be pronounced in regions where climate and atmospheric deposition are dominant drivers but muted in more human-dominated landscapes with a limited extent of organic soils where other disturbances predominate.

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Source-reported bounding extent: 38.928519° to 49.384358° latitude; -97.238387° to -66.986318° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Jean-Francois Lapierre, Sarah M. Collins, Samantha K. Oliver, Emily H. Stanley, Tyler Wagner. 2021-03-08. Inconsistent browning of northeastern U.S. lakes despite increased precipitation and recovery from acidification. https://doi.org/10.1002/ecs2.3415

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