Zooplankton impacts on chlorophyll and transparency in Onondaga Lake,New York,USA |
| |
Authors: | Auer Martin T Storey Michelle L Effler Steven W Auer Nancy A Sze Philip |
| |
Institution: | (1) Department of Civil and Environmental Engineering, Michigan Technological, University, 49931 Houghton, Michigan, USA;(2) Department of Biological Sciences, Michigan Technological University, 49931 Houghton, Michigan, USA;(3) Upstate Freshwater Institute, P.O. Box 506, 13214 Syracuse, New York, USA;(4) Department of Biology, Georgetown University, 20057 Washington DC, USA |
| |
Abstract: | The transparency of polluted, hypereutrophic Onondaga Lake, New York, USA has improved substantially in the late 1980's as
a result of reductions in phytoplankton biomass, in the absence of significant reductions in external phosphorus loading.
Much of this improvement has been due to the occurrence of clearing events, e.g. sudden and dramatic increases in transparency.
Field measurements, laboratory experiments, and modelling analyses were utilized to identify processes regulating phytoplankton
standing crop during the spring to fall interval of 1987. Changes in the zooplankton community documented over the past decade
support the conclusion that increased zooplankton grazing has contributed to improvements in transparency. Herbivores now
represent a greater fraction of the zooplankton population and more efficient cladocerans are present in greater numbers.
Biomanipulation practices, e.g. reestablishment of piscivorous species, designed to reduce the abundance of planktivorous
fish species in Onondaga Lake, may serve to reduce pressure on the grazing community and thus result in further improvements
in transparency. |
| |
Keywords: | clearing events chlorophyll phosphorus zooplankton |
本文献已被 SpringerLink 等数据库收录! |
|