Modeling the Impacts of Multiple Environmental Stress Factors on Estuarine Copepod Populations

Abstract

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 af f inis 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. af f inis 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.

Copepods as References Species in Estuarine and Marine Waters

“…Among the different IBMs developed for copepod so far, some effectively integrate and quantify the impact of both natural and anthropogenic forcing (Belleza et al, 2014;Kulkarni et al, 2014;Korsman et al, 2014) and showed the difference between individual-level and population-level sensitivities (Kulkarni et al, 2014). Those results confirm that models are valuable tools in predicting population-level responses from individual-level data and therefore ecological risk assessment of chemicals.…”

Temperature and food quantity effects on the harpacticoid copepod Nitocra spinipes: Combining in vivo bioassays with population modeling

“…When taking into account toxic exposure scenarios, and additional climate change-related stressors (e.g. salinity, pH, hypoxia and ultraviolet radiation), the simultaneous use of multiple stress functions is indispensable for informative model predictions [34, 77]. Multivariate stress equations may be established to yield more precise model predictions on interactive stress effects [19].…”

Contaminant curiosity and pollutant puzzles: Conceptual insights in ecotoxicity and practical implementation of higher-tiered risk assessment.

“…Based on these models, toxic and nontoxic stressors were demonstrated to affect, e.g. copepods and eagles exposed to sediments in Dutch and Flemish deltas (Korsman et al, 2012; 2014).…”