190 likes | 198 Views
Dynamic energy budgets in individual based population models Cross species test and application. A. Gergs · H. Selck · M. Hammers-Wirtz · A. Palmqvist. Extrapolations in risk assement of chemicals. Constant vs. time variable exposure
E N D
Dynamic energy budgets in individual based population models Cross species test and application A. Gergs · H. Selck · M. Hammers-Wirtz · A. Palmqvist
Extrapolations in risk assement of chemicals • Constant vs. time variable exposure • Extrapolation of population level effects from individual level toxicity tests • Laboratory to field extrapolation • … Mechanistic effect modelling
Individual-basedpopulationmodel (IBM) Individual organism Individual organism • Individual organism • life history traits • behaviours • food conditions • toxic exposure
newborn Feeding embryo development Ageing brood size maximal age ? yes no growth born juveniles no Adult? Birthing? no yes yes juvenile development Conceptual illustration of the IBM approach Preuss et al. (2009) Ecological Modelling 220: 310-329
Comparabilityof IBMs Strauss et al. (2016) EcologicalModelling 321: 84-97 Kulkarni et al. (2014) Chemosphere 112: 340–347
Dynamic energy budgets in IBMs Abundance [#] Time [d] Stage dependent mortality Figure: Martin et al (2013) American Naturalist 181: 506-519
Size dependentstarvationresistance Notonecta maculata Daphnia magna Fraction surviving [-] Fraction surviving [-] Time [d] Time [d] Assumption scaled mobilisation flux is changed in a way that somatic maintenance costs are always paid Scaled reserve density [-] Time [d] Gergs & Jager (2014) Journal of Animal Ecology 83: 758–768
DEB parametrizationforDaphnia magna Filtration rate Size dependent starvation Growth Reproduction Gergs et al. (2014) PlosOne 9: e91503
Emerging populationdynamics mean, range
Emerging populationdynamics data model
Cross speciestransferability Growth Reproduction Gergs et al. (in prep.)
Cross speciestest data model Food availability Gergs et al. (in prep.)
Toxicokinetic-toxicodynamic effectmodels Toxicodynamics Toxicokinetics scaled internal concentration x internal concentration damage effect model • Physiological modes ofaction • Assimilation • Maintenance costs • Cost forstructure • Cost for reproduction • Hazardduringoogenesis GUTS schememodifiedfrom: Jager et al. (2011) ES&T 45, 2529–2540
Lethaleffects Mortality Population dynamics Population size [#] Survival [-] Concentration [µg/L] Time [days] Time [days] Model prediction (minimum, mean, maximum) Effect data Range control data Exposure
Bioaccumulation Bioaccumulation Population dynamics Internal concentration [dpm/g] Population size [#] Concentration [µg/L] Time [days] Time [h] Model prediction size scaling Model prediction NO size scaling Effect data Range control data Exposure Gergs et al. (2016) Environmental Science and Technology 50, 6017−6024
Sublethaleffect Effect on reproduction Population dynamics 85µg/L Cummulative offspring [#] Population size [#] Time [days] Time [days] Model prediction (minimum, mean, maximum) Data Control condition Gergs et al. (in prep.)
Conclusion • DEB models allow for the standardized development of IBMs • This facilitates the analysis of life history contributions to population dynamics across species and ecological systems • When combined with process based effect models, the DEB integration with IBMs enable a straightforward propagation of population and community level effects from individual level toxicity testing
Thank you for your attention Long-range Research Initiative (project no. ECO28) ModNanoTox funded by the European Union (project no. 266712)