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Record-setting algal bloom in Lake Erie caused by agricultural and meteorological trends consistent with expected future conditions.

ABSTRACT: In 2011, Lake Erie experienced the largest harmful algal bloom in its recorded history, with a peak intensity over three times greater than any previously observed bloom. Here we show that long-term trends in agricultural practices are consistent with increasing phosphorus loading to the western basin of the lake, and that these trends, coupled with meteorological conditions in spring 2011, produced record-breaking nutrient loads. An extended period of weak lake circulation then led to abnormally long residence times that incubated the bloom, and warm and quiescent conditions after bloom onset allowed algae to remain near the top of the water column and prevented flushing of nutrients from the system. We further find that all of these factors are consistent with expected future conditions. If a scientifically guided management plan to mitigate these impacts is not implemented, we can therefore expect this bloom to be a harbinger of future blooms in Lake Erie.

SUBMITTER: Michalak AM

PROVIDER: S-EPMC3631662 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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Record-setting algal bloom in Lake Erie caused by agricultural and meteorological trends consistent with expected future conditions.

Michalak Anna M AM Anderson Eric J EJ Beletsky Dmitry D Boland Steven S Bosch Nathan S NS Bridgeman Thomas B TB Chaffin Justin D JD Cho Kyunghwa K Confesor Rem R Daloglu Irem I Depinto Joseph V JV Evans Mary Anne MA Fahnenstiel Gary L GL He Lingli L Ho Jeff C JC Jenkins Liza L Johengen Thomas H TH Kuo Kevin C KC Laporte Elizabeth E Liu Xiaojian X McWilliams Michael R MR Moore Michael R MR Posselt Derek J DJ Richards R Peter RP Scavia Donald D Steiner Allison L AL Verhamme Ed E Wright David M DM Zagorski Melissa A MA

Proceedings of the National Academy of Sciences of the United States of America 20130401 16

In 2011, Lake Erie experienced the largest harmful algal bloom in its recorded history, with a peak intensity over three times greater than any previously observed bloom. Here we show that long-term trends in agricultural practices are consistent with increasing phosphorus loading to the western basin of the lake, and that these trends, coupled with meteorological conditions in spring 2011, produced record-breaking nutrient loads. An extended period of weak lake circulation then led to abnormall ...[more]

PMID: 23576718

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Dataset Information

Record-setting algal bloom in Lake Erie caused by agricultural and meteorological trends consistent with expected future conditions.

Publications

Record-setting algal bloom in Lake Erie caused by agricultural and meteorological trends consistent with expected future conditions.

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