{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T01:15:34Z","timestamp":1788311734201,"version":"build-2803163510"},"reference-count":46,"publisher":"American Chemical Society (ACS)","issue":"15","license":[{"start":{"date-parts":[[2020,7,15]],"date-time":"2020-07-15T00:00:00Z","timestamp":1594771200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/pubs.acs.org\/page\/policy\/authorchoice_termsofuse.html"}],"funder":[{"DOI":"10.13039\/100000203","name":"U.S. Geological Survey","doi-asserted-by":"publisher","award":["NA"],"award-info":[{"award-number":["NA"]}],"id":[{"id":"10.13039\/100000203","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/na","name":"Idaho Department of Environmental Quality","doi-asserted-by":"publisher","award":["NA"],"award-info":[{"award-number":["NA"]}],"id":[{"id":"10.13039\/na","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/na","name":"Idaho Power","doi-asserted-by":"publisher","award":["NA"],"award-info":[{"award-number":["NA"]}],"id":[{"id":"10.13039\/na","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2020,8,4]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>The Hells Canyon Complex (HCC) along the Snake River (Idaho\u2013Oregon border, U.S.A.) encompasses three successive reservoirs that seasonally stratify, creating anoxic conditions in the hypolimnion that promote methylmercury (MeHg) production. This study quantified seasonal dynamics and interannual variability in mercury concentrations (inorganic divalent mercury (IHg) and MeHg) and loads at four reservoir inflow and outflow locations through the HCC (2014\u20132017). We observed (1) that the HCC is a net sink for both IHg and MeHg, (2) interannual variability in IHg and MeHg loads largely reflecting streamflow conditions, and (3) seasonal variability in particulate IHg loading at the inflow (greatest from February to April) and MeHg export from the outflow (greatest from September to December) of the HCC. Seasonal export of MeHg was evidenced by increases in monthly mean concentrations of unfiltered MeHg (approximately 2-fold) and the percentage of total mercury (THg) as MeHg (\u22654-fold) coincident with reservoir destratification. Despite evidence of seasonal export of MeHg from the HCC, annual loads indicate a 42% decrease in unfiltered MeHg from HCC inflow to outflow. Results from this study improve the understanding of seasonal variability in mercury transport through and transformation within a reservoir complex.<\/jats:p>","DOI":"10.1021\/acs.est.9b07103","type":"journal-article","created":{"date-parts":[[2020,7,15]],"date-time":"2020-07-15T15:29:41Z","timestamp":1594826981000},"page":"9305-9314","source":"Crossref","is-referenced-by-count":15,"title":["Seasonal\nDynamics and Interannual Variability in Mercury\nConcentrations and Loads through a Three-Reservoir Complex"],"prefix":"10.1021","volume":"54","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6027-3823","authenticated-orcid":true,"given":"Austin K.","family":"Baldwin","sequence":"first","affiliation":[{"name":"U.S. Geological Survey , 230 Collins Road , , ,","place":["Boise, Idaho, United States, 83702"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5555-7733","authenticated-orcid":true,"given":"Brett A.","family":"Poulin","sequence":"additional","affiliation":[{"name":"U.S. Geological Survey , 3215 Marine Street, Suite E127 , , ,","place":["Boulder, Colorado, United States, 80303"]},{"name":"University of California Davis , , 1 Shields Avenue , , ,","place":["Davis, CA, United States, 95616"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jesse","family":"Naymik","sequence":"additional","affiliation":[{"name":"Idaho Power Company , 1221 West Idaho Street , , ,","place":["Boise, Idaho, United States, 83702"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Charles","family":"Hoovestol","sequence":"additional","affiliation":[{"name":"Idaho Power Company , 1221 West Idaho Street , , ,","place":["Boise, Idaho, United States, 83702"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gregory M.","family":"Clark","sequence":"additional","affiliation":[{"name":"U.S. Geological Survey , 230 Collins Road , , ,","place":["Boise, Idaho, United States, 83702"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1964-5020","authenticated-orcid":true,"given":"David P.","family":"Krabbenhoft","sequence":"additional","affiliation":[{"name":"U.S. Geological Survey , 8505 Research Way , , ,","place":["Middleton, Wisconsin, United States, 53562"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2020,7,15]]},"reference":[{"issue":"1\u20134","key":"2026090120502593300_cit1","doi-asserted-by":"publisher","first-page":"61","DOI":"10.1023\/A:1015573621474","article-title":"Methylmercury in\nFlood-Control Impoundments and Natural Waters of Northwestern Minnesota,\n1997\u201399","volume":"138","author":"Brigham","year":"2002","journal-title":"Water, Air, Soil Pollut."},{"issue":"1","key":"2026090120502593300_cit2","doi-asserted-by":"publisher","first-page":"147","DOI":"10.1016\/S0048-9697(00)00559-3","article-title":"Temporal and Spatial Influences of\nFlooding on Dissolved Mercury in Boreal Reservoirs","volume":"260","author":"Montgomery","year":"2000","journal-title":"Sci. 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Environ.\nMicrobiol."},{"issue":"11","key":"2026090120502593300_cit5","doi-asserted-by":"publisher","first-page":"2281","DOI":"10.1021\/es00035a029","article-title":"Sulfate Stimulation\nof Mercury Methylation\nin Freshwater Sediments","volume":"26","author":"Gilmour","year":"1992","journal-title":"Environ. Sci. Technol."},{"issue":"20","key":"2026090120502593300_cit6","doi-asserted-by":"publisher","first-page":"11810","DOI":"10.1021\/es403075t","article-title":"Mercury\nMethylation by Novel Microorganisms from New\nEnvironments","volume":"47","author":"Gilmour","year":"2013","journal-title":"Environ. Sci. Technol."},{"issue":"12","key":"2026090120502593300_cit7","doi-asserted-by":"publisher","first-page":"7919","DOI":"10.1128\/AEM.01602-06","article-title":"Mercury Methylation\nby Dissimilatory Iron-Reducing\nBacteria","volume":"72","author":"Kerin","year":"2006","journal-title":"Appl. Environ. 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C.; Chasar, L. C.; Wentz, D. A.; Bauch, N. J.; Brigham, M. E.; Moran, P. W.; Krabbenhoft, D. P.\n          Mercury in\nFish, Bed Sediment, and Water from Streams Across the United States,\n1998\u20132005;  Scientific Investigations\nReport; USGS Numbered Series 2009\u20135109; U.S. Geological Survey, 2009.","DOI":"10.3133\/sir20095109"},{"key":"2026090120502593300_cit37","volume-title":"Mercury and Heavy Metal Contamination\nin the Jordan Creek Drainage near Silver City, Owyhee County, Idaho","author":"Williams","year":"1974"},{"key":"2026090120502593300_cit38","doi-asserted-by":"publisher","DOI":"10.1029\/2009WR0083","article-title":"Mercury\nDynamics\nin Relation to Dissolved Organic Carbon Concentration and Quality\nduring High Flow Events in Three Northeastern U.S. Streams","volume":"46","author":"Dittman","year":"2010","journal-title":"Water Resour. 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