Modeling the impacts of multiple environmental stress factors on estuarine copepod populations.
Many studies have focused on natural stress factors that shape the spatial and temporal distribution of calanoid copepods, but bioassays have shown that copepods are also sensitive to a broad range of contaminants. Although both anthropogenic and natural stress factors are obviously at play in natural copepod communities, most studies consider only one or the other. In the present investigation, we modeled the combined impact of both anthropogenic and natural stress factors on copepod populations. The model was applied to estimate Eurytemora affinis densities in the contaminated Scheldt estuary and the relatively uncontaminated Darß-Zingst estuary in relation to temperature, salinity, chlorophyll a, and sediment concentrations of cadmium, copper, and zinc. The results indicated that temperature was largely responsible for seasonal fluctuations of E. affinis densities. Our model results further suggested that exposure to zinc and copper was largely responsible for the reduced population densities in the contaminated estuary. The model provides a consistent framework for integrating and quantifying the impacts of multiple anthropogenic and natural stress factors on copepod populations. It facilitates the extrapolation of laboratory experiments to ecologically relevant end points pertaining to population viability.
Institute for Water and Wetland Research, Department of Environmental Science, Radboud University Nijmegen , Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
John C
JC
Korsman
Aafke M
AM
Schipper
Lisette
L
De Hoop
Benoit
B
Mialet
Tom
T
Maris
Micky L M
ML
Tackx
A Jan
AJ
Hendriks
D000818:Animals; D001681:Biological Assay; D002104:Cadmium / Q000633:toxicity; D033342:Copepoda / Q000187:drug effects / Q000502:physiology*; D003300:Copper / Q000633:toxicity; D004784:Environmental Monitoring; D063366:Estuaries; D006802:Human Activities; D006801:Humans; D008962:Models, Theoretical; D011156:Population Density; D012098:Reproduction / Q000187:drug effects; D054712:Salinity; D013312:Stress, Physiological / Q000187:drug effects; D013696:Temperature; D015032:Zinc / Q000633:toxicity
D002104:Cadmium; D003300:Copper; D015032:Zinc