Early onset of a microcystin-producing cyanobacterial bloom in an agriculturally-influenced Great Lakes tributary

作     者：Robert Michael L.McKAY Taylor TUTTLE Laura A.REITZ George S.BULLERJAHN William R.CODY Adam J.McDOWELL Timothy W.DAVIS 

作者机构：Department of Biological Sciences Bowling Green State University Bowling Green OH 43403 USA Aquatic Taxonomy Specialists Malinta OH 43535 USA City of Defiance Water Division Defiance OH 43512 USA NOAA Great Lakes Environmental Research Laboratory Ann Arbor MI USA 

出 版 物：《Journal of Oceanology and Limnology》 (海洋湖沼学报（英文）)

年 卷 期：2018年第36卷第4期

页      面：1112-1125页

核心收录：

学科分类：0710[理学-生物学] 071001[理学-植物学] 0908[农学-水产] 07[理学] 0707[理学-海洋科学] 09[农学] 0815[工学-水利工程] 0903[农学-农业资源与环境] 0713[理学-生态学] 

基　　金：Supported by a Harmful Algal Bloom Research Initiative Grant(No.R/HAB-2-ODHE)from the Ohio Department of Higher Education(GSB,RMLM) Ohio Sea Grant College Program grant R/ER-114(GSB,RMLM) 

主　　题：伊利湖 蓝藻 生态系统 生物学 

摘      要：In late May 2016, a cyanobacterial harmful algal bloom(cHAB) was detected in the Maumee River, the largest tributary to Lake Erie, the southernmost lake of the Laurentian Great Lakes system. Testing on 31 May identified Planktothrix agardhii as the dominant cyanobacterium with cell abundance exceeding 1.7×10~9 cells/L and total microcystins(MC) reaching 19 μg/L MC-LR equivalents, a level over 10-fold higher than the 2015 revised U.S. Environmental Protection Agency(EPA) national health advisory levels for drinking water exposure to adults. Low river discharge coincident with negligible precipitation through the latter half of May coincided with an 80% decline in river turbidity that likely favored bloom formation by a low-light adapted P. agardhii population. Also contributing to the c HAB were high initial nutrient loads and an increase of the river temperature from 13℃ to 26℃ over this same period. The bloom persisted through 5 June with microcystins exceeding 22 μg/L MC-LR equivalents at the bloom peak. By 6 June, the river had returned to its muddy character following a rain event and sampling on 7 June detected only low levels of toxin(0.6 μg/L) at public water systems located near the bloom origin. The elevated toxin production associated with this early onset bloom was without precedent for the Maumee River and an unique attribute of the c HAB was the high proportion of potentially-toxic genotypes. Whereas Planktothrix spp. is common in lotic environments, and has been previously detected in the Maumee, blooms are not commonly reported. This early onset, microcystin-producing c HAB provided a rare opportunity to glean insights into environmental factors that promote bloom development and dominance by Planktothrix in lotic environments.