TY - JOUR
T1 - Phytoplankton dynamics and hypoxia in Lake Erie
T2 - A hypothesis concerning benthic-pelagic coupling in the central basin
AU - Carrick, Hunter J.
AU - Moon, Jessica B.
AU - Gaylord, Barrett F.
N1 - Funding Information:
We appreciate the efforts of Penn State students Jamie Bosilvecja, Corianne Iacovelli, Morgan Johnston, and Katie Nickles who provided technical assistance to the project. Glenn Warren and David Rockwell generously provided physical-chemical data for us use as collected by the U.S. EPA during their surveys of Lake Erie. We also thank the crew of the R/V Lake Guardian, especially Captain Robert Christensen and Seaman Amy Strong. This research was supported by a grant from the Environmental Protection Agency (GLNPO) to Gerald Matisoff and Jan Ciborowski, as subcontracted to Hunter Carrick.
PY - 2005
Y1 - 2005
N2 - Recent changes in the Lake Erie ecosystem suggest that reductions in phosphorus loads and invasion by dreissenid mussels, have enhanced light penetration, and altered phytoplankton distribution patterns in the lake. In this paper, we evaluate possible links between phytoplankton dynamics in Lake Erie, and seasonal development of hypoxia in the central basin by studying seasonal pattern of the vertical distribution of algae. On four occasions in 2002, the biomass of major algal assemblages was measured (epilimnion, metalimnion, hypolimnion, and benthos) at six sites in the central basin (n = 96). Pelagic chlorophyll concentrations in the central basin varied by several fold among the six sampling sites and three dates (range, 0.80 to 5.99 mg/m3). The greatest values were measured in the metalimnion. Benthic chlorophyll concentrations in the central basin were large. Values were highest in June and decreased dramatically thereafter. Mean (± SD) concentrations for the benthic assemblages at two stations were 31.1 ± 18.9 mg/m2, compared with values of 43.2 ± 9.2 mg/m2 for the pelagic assemblage at the same two stations. The consistent presence of a benthic algal assemblage in the central basin, whose species make-up was dominated by planktonic diatoms, suggests that the benthic assemblage in the central basin is more aptly viewed as a meroplanktonic algal maximum (MAM); an algal assemblage that spends part of its life history associated with both the pelagic and benthic environments. On a unit area basis, this MAM layer supported biomass comparable to that for the entire water column, suggesting that the MAM figures prominently into the development of hypoxia.
AB - Recent changes in the Lake Erie ecosystem suggest that reductions in phosphorus loads and invasion by dreissenid mussels, have enhanced light penetration, and altered phytoplankton distribution patterns in the lake. In this paper, we evaluate possible links between phytoplankton dynamics in Lake Erie, and seasonal development of hypoxia in the central basin by studying seasonal pattern of the vertical distribution of algae. On four occasions in 2002, the biomass of major algal assemblages was measured (epilimnion, metalimnion, hypolimnion, and benthos) at six sites in the central basin (n = 96). Pelagic chlorophyll concentrations in the central basin varied by several fold among the six sampling sites and three dates (range, 0.80 to 5.99 mg/m3). The greatest values were measured in the metalimnion. Benthic chlorophyll concentrations in the central basin were large. Values were highest in June and decreased dramatically thereafter. Mean (± SD) concentrations for the benthic assemblages at two stations were 31.1 ± 18.9 mg/m2, compared with values of 43.2 ± 9.2 mg/m2 for the pelagic assemblage at the same two stations. The consistent presence of a benthic algal assemblage in the central basin, whose species make-up was dominated by planktonic diatoms, suggests that the benthic assemblage in the central basin is more aptly viewed as a meroplanktonic algal maximum (MAM); an algal assemblage that spends part of its life history associated with both the pelagic and benthic environments. On a unit area basis, this MAM layer supported biomass comparable to that for the entire water column, suggesting that the MAM figures prominently into the development of hypoxia.
KW - Dissolved oxygen
KW - Lake Erie
KW - Meroplankton
KW - Phytoplankton
KW - Subsurface chlorophyll maximum
UR - http://www.scopus.com/inward/record.url?scp=33745714902&partnerID=8YFLogxK
U2 - 10.1016/S0380-1330(05)70308-7
DO - 10.1016/S0380-1330(05)70308-7
M3 - Article
AN - SCOPUS:33745714902
VL - 31
SP - 111
EP - 124
JO - Journal of Great Lakes Research
JF - Journal of Great Lakes Research
SN - 0380-1330
IS - SUPPL. 2
ER -