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Mechanistic Effect Modelling

Analyze - Understand - Forecast

Development and application of ecological models in environmental risk assessment

Mechanistic effect modelling

Ecological numeric modelling becomes increasingly important for the environmental risk assessment (ERA) of plant protection products. Models can be used, for example, to support the evaluation of experimental studies as well as to extrapolate experimental results to complex field situations.

gaiac has many years of experience in the use of dynamic simulation models, and offers the application, adaptation and development of models for ERA and Risk Management.

Our toolbox

Effect models:

  • Lethal effects: TKTD model framework GUTS
  • Sub-lethal effects: DEB-TKTD approach

Individual-based population models (IBMs):

  • Daphnia magna
  • Chaoborus crystallinus
  • Asellus aquaticus
  • Mayfly population model (Cloeon dipterum)
  • Earthworm-2D-migration model in soil for: Lumbricus terrestris, Aporrectodea caliginosa, Eisenia fetida 

Ecosystem models:

  • StoLaM (Stoichiometric Lake Model): a complex, dynamic water quality model for lakes and shallow waters including modules for zooplankton and phytoplankton
  • Phytoplankton model as a building block in the lake model StoLaM, applicable for the modeling of algae species from bioassays in the laboratory to aquatic ecosystems (according to the pelagic microalgae model, EFSA Scientific Opinion on TKTD models, 2018)
  • DaLaM (coupled hybrid model of GUTS, IDamP, and StoLaM)
  • STREAMcom (DEB-IBM based community model for streams, includes organisms such as mayflies, amphipods, isopods, snails, and others)
  • GraS-Modell (spatially-explicit and process-based succession model for plant communities)
more about landscape modeling
Schematic illustration of the models used at gaiac in effect modelling

Our modelling concept

In the area of modeling, we believe it is important that…

  • data and modelling go hand in hand
  • model development is target oriented
  • models are tested against independent data

Our mechanistic population and ecosystem models…

  • combine difference equation models, TK-TD and individual-based model approaches to extrapolate population responses under field conditions from laboratory toxicity tests
  • link time-variable exposure and effects
  • are tested based on laboratory tests, outdoor mesocosms, or field studies
  • allow for quantitative evaluation of direct and indirect effects as well as delayed effects and ecological recovery
  • enable the simulation of variable species specific ecological scenarios (laboratory to field conditions), including dynamic resources, climate or weather conditions and spatial dimensions
  • allow the combined simulation of natural and anthropogenic stressors

Our tiered modelling approach

Effect models

For modeling lethal effects on individuals, we use toxicokinetic-toxicodynamic (TK-TD) models and, in particular, the GUTS (General Unified Threshold model of Survival) approach, which integrates several TK-TD models into one framework and allows the simulation of survival under predefined assumptions.

In addition, Dynamic Energy Budget (DEB) models offer a coherent way to interpret sublethal effects on life history processes of individuals such as growth and reproduction (DEB-TKTD approach).

Population models

We simulate populations under field and laboratory conditions. For this, we use Individual Based population Models (IBMs) which allow the straight forward propagation of chemical effects observed at the organism level to responses at higher levels of biological complexity, such as populations and communities.

Ecosystem models

We simulate communities, i.e. interacting populations, in standing waters under field and semi-field conditions for phytoplankton, zooplankton, aquatic insects and other invertebrates. Both simple and complex ecosystem and hydrodynamic models can be added to provide an appropriate environment containing the most important biological and physico-chemical drivers (StoLaM model).

We are also developing spatially explicit individual-based population and community models for running waters and streams, whose aquatic assemblages include focal species from various groups such as mayflies, amphipods, isopods, snails and fish (STREAMcom model).

The dynamic and spatially explicit GraS-Model enables analyses and projections of plant communities and thus vegetation dynamics of real landscapes depending on different environmental stressors (e.g. soil properties, temperature, management).

more about landscape modeling

First use of a gaiac model in the risk assessment of pesticides

2002

Number of modeling studies for risk assessment

33

Contributions to the Add-my-Pet database for species specific DEB parameters

20

Number of implemented individual-based population models

6

Number of implemented ecosystem models

3

Dr. Tido Strauss

Phone: +49 241 – 8027601
E-Mail: strauss@gaiac- eco.de

Kim Rakel

Phone: +49 241 – 8027106
E-Mail: rakel@gaiac-eco.de

Dr. Josef Koch

Phone: +49 241 – 8027106
E-Mail: koch@gaiac-eco.de

Brochures

Flyer
Mechanistic effect modelling

Good Laboratory Practice

(GLP)

Taxonomic expertise

References

Projects

2019-2020
Preparation and organization of an international workshop in January 2020: FORESEE - (In)Field Organism Risk modelling by coupling Soil Exposure and Effects | ECPA, the European Crop Protection Association
2015-2018
Modelling approaches for a scenario based assessment of chemically induced impacts on aquatic macroinvertebrate communities | CEFIC, The European Chemical Industry Council
2015-2018
SIGN - CLIENT China Verbundprojekt SIGN: Sino-German water supply network - Clean water from the source to the tap, Teilprojekt J | BMBF, FKZ 02WCL1336J
2012-2013
MeTox - Integration and calibration of a biodynamic toxicity module for metals in the ecological modell AQUATOX - Teil Durchführung von Biotests mit aquatischen Nichtstandard-Invertebraten | Öffentliches Forschungszentrum (CRP) Henri Tudor

Publications & Presentations

2022
Rakel, K., Becker, D., Bussen, D., Classen, S., Preuss, T., Strauss, T., Zenker, A., Gergs, A. (2022): Physiological dependency explains temperature differences in sensitivity towards chemical exposure. Archives of Environmental Contamination and Toxicology 83 (4). DOI: 10.1007/s00244-022-00963-2.
Publication
2022
Koch, J., Dallmann, N., Strauss, T. (2022): DEBgen: a generalised model formulation to incorporate common deviations from the standard model of Dynamic Energy Budget theory. Poster presentation, SETAC Europe 32nd Annual Meeting, 15-19 May 2022, Copenhagen, Denmark.
2022
Schmolke, A., Galic, N., Bartell, S., Atalay, Y., O’Connor, I., Spycher, S., Schuwirth, N., Strauss, T., Sackmann, B., Preziosi, D., Pastorok, R., Ebke, P., Schmidt, J., Loerracher, A.-K., Abi-Akar, F., Collins, J., Ashauer, R. (2022): Comparative ecosystem modeling study for assessing pesticide risks in aquatic mesocosms. Poster presentation, SETAC Europe 32nd Annual Meeting, 15-19 May 2022, Copenhagen, Denmark.
2022
Strauss, T., Ashauer, R., Galic, N., Gerhard, J., Koch, J., Schmidt, J., Schmolke, A. (2022): Validating models with experiments, or interpreting experimental data with models - The advantages of using IBM-based approaches to modelling aquatic mesocosms. Poster presentation, SETAC Europe 32nd Annual Meeting, 15-19 May 2022, Copenhagen, Denmark.
2021
Focks, A., Axelman, J., Barsi, A., Becker, J., Chaideftou, E., Charles, S., Duquesne, S., Goussen, B., Hommen, U., Jakoby, O., Kattwinkel, M., Klein, J., Koch, J., Preuss, T. G., Reed, M., Reichenberger, S., Rendal, C., Strauss, T., Thorbek, P., Vermeiren, P., Wang, M. (2021): The SETAC working group "Model Acceptability, version control and scenario Development (MAD)". Poster presentation, SETAC Europe 31st Annual Meeting, 03-06 May 2021, Virtual Conference.
2021
Strauss, T., Bub, S., Gerhard, J., Schad, T. (2021): Linking time-variable exposure on catchment scale to effects on stream populations in realistic landscapes. Poster presentation, SETAC Europe 31st Annual Meeting, 03-06 May 2021, Virtual Conference.
2019
Gergs, A., Rakel, K., Liesy, D., Zenker, A., Classen, S. (2019): Mechanistic effect modeling approach for the extrapolation of species sensitivity. Environmental Science & Technology, 53 (16), 9818-9825.
Publication
2019
Hammers-Wirtz, M., Classen, S., Strauss, T. (2019): Non-standard biotests – Intelligent testing to combine different needs and requirements for experimental and modelling approaches. Poster presentation, SETAC Europe 29th Annual Meeting, 26-30 May 2019, Helsinki, Finland.
2019
Rakel, K., Strauss, T., Gergs, A. (2019): The STREAMcom model - Linking time variable exposure to effects on individuals, populations and community in realistic landscapes. Poster presentation, SETAC Europe 29th Annual Meeting, 26-30 May 2019, Helsinki, Finland.
2019
Strauss, T., Klein, J., Rakel, K. (2019): Measure or extrapolate? Extended parameterisation of TKTD models for population modeling under outdoor conditions. Platform presentation, SETAC Europe 29th Annual Meeting, 26-30 May 2019, Helsinki, Finland.
2018
Ladermann, K., Classen, S., Strauss, T., Hammers-Wirtz, M., Gergs, A. (2018): Impact of temperature on species sensitivity distribution in aquatic invertebrates. Poster presentation, SETAC Europe 28th Annual Meeting, 13-17 May 2018, Rome, Italy.
Poster
2018
Rakel, K., Liesy, D., Classen, S., Strauss, T., Zenker, A., Gergs, A. (2018): Bridging the gap across species by the means of TK-TD modelling. Poster presentation, SETAC Europe 13th Special Science Symposium, 23-24 October 2018, Brussels, Belgium.
Poster
2018
Strauss, T. (2018): Integration of temperature-dependent TKTD kinetics in individual-based population modelling – A case study with Chaoborus crystallinus. Platform presentation, SETAC Europe 28th Annual Meeting, 13-17 May 2018, Rome, Italy.
Presentation
2018
Strauss, T., Gergs, A., Ladermann, K., Hammers-Wirtz, M. (2018): Defining ecological lake scenarios for population modelling as part of the Ecological Risk Assessment of chemicals. Poster presentation, SETAC Europe 28th Annual Meeting, 13-17 May 2018, Rome, Italy.
2017
Gergs, A., Thorbek, P., Finnegan, M., Strauss, T. (2017): Individual-based analysis of mayfly meta-population dynamics. Poster presentation, SETAC Europe 27th Annual Meeting, 07-11 May 2017, Brussels, Belgium.
Poster
2017
Strauss, T., Gabsi, F., Hammers-Wirtz, M., Thorbek, P., Preuss, T. G. (2017): The power of hybrid modelling: An example from aquatic ecosystems. Ecological Modelling 364: 77-88. DOI: 10.1016/j.ecolmodel.2017.09.019.
Publication
2017
Strauss, T., Preuss, T. G. (2017): Modelling laboratory standard biotests with Daphnia magna. Poster presentation, SETAC Europe 27th Annual Meeting, 07-11 May 2017, Brussels, Belgium.
Poster
2016
Dohmen, P., Preuss, T. G., Hamer, M., Galic, N., Strauss, T., Van den Brink, P. J., De Laender, F., Bopp, S. (2016): Population‐level effects and recovery of aquatic invertebrates after multiple applications of an insecticide. Integrated Environmental Assessment and Management 12: 67-81. DOI: 10.1002/ieam.1676.
Publication
2016
Strauss, T., Bruns, E., Witt, J., Preuss, T. G. (2016): Modelling the impact of herbicides on phytoplankton for relevant ecological scenarios of varying complexity. Poster presentation, SETAC Europe 26th Annual Meeting, 22-26 May 2016, Nantes, France.
2016
Strauss, T., Kulkarni, D., Preuss, T. G., Hammers-Wirtz, M. (2016): The secret lives of cannibals: Modelling density-dependent processes that regulate population dynamics in Chaoborus crystallinus. Ecological Modelling 321: 84-97. DOI: 10.1016/j.ecolmodel.2015.11.004.
Publikation
2013
Strauss, T. (2013): Incorporating ecological scenarios into population modelling for use in aquatic risk assessment - A simulation study for the emerging insect Chaoborus. Poster presentation, SETAC Europe 23rd Annual Meeting, 12-16 May 2013, Glasgow, Scotland.
Poster
2012
Kulkarni, D., Strauss, T., Hommen, U., Ratte, H. T., Preuss, T. G. (2012): Using a modelling approach to compare sensitivities to Triphenyltin at the individual and population levels for three planktonic organisms. Platform presentation, 6th SETAC World Congress/SETAC Europe 22nd Annual Meeting, 20-24 May 2012, Berlin, Germany.
2012
Strauss, T., Preuss, T. G. (2012): Aquatic ecosystem model framework for use in refined environmental risk assessment. Poster presentation, 6th SETAC World Congress/SETAC Europe 22nd Annual Meeting, 20-24 May 2012, Berlin, Germany.
Poster
2011
Strauss, T., Bruns, E., Goerlitz, G., Preuss, T. G. (2011): Modelling toxic effects on Chaoborus populations under field conditions - an individual-based simulation study. Poster presentation, SETAC Europe 21st Annual Meeting, 15-19 May 2011, Milano, Italy.
Poster
2010
Preuss, T., Bruns, E., Thorbek, P., Hammers-Wirtz, M., Schäfer, D., Goerlitz, G., Ratte, H. T., Strauss, T. (2010): Can population modelling answer urgent unresolved questions for ecological risk assessment - lessons learnt from Daphnia. Poster presentation, SETAC Europe 20th Annual Meeting, 23-27 May 2010, Seville, Spain.
2010
Strauss, T. (2010): Density-dependent compensation of toxic effects in Chaoborus crystallinus populations - an individual-based simulation study. Poster presentation, SETAC Europe 20th Annual Meeting, 23-27 May 2010, Seville, Spain.
Poster
2009
Strauss, T. (2009): Dynamische Simulation der Planktonentwicklung und interner Stoffflüsse in einem eutrophen Flachsee. Dissertation RWTH Aachen: 244 S. Shaker, Aachen. ISBN: 978-3-8322-8501-2.
Dissertation
2009
Strauss, T., Ratte, H. T., Hammers-Wirtz, M., Thorbek, P., Preuss, T. G. (2009): Modeling toxic effects on Daphnia magna populations under natural field conditions. Poster presentation, SETAC Europe 19th Annual Meeting, 01-04 June 2009, Göteborg, Sweden.
Poster
2007
Strauss, T., Sevim, S., Ratte, H. T. (2007): Individual-based modelling of the recovery of Chaoborus crystallinus in aquatic mesocosm pond studies. Poster presentation, SETAC Europe 17th Annual Meeting, 20-24 May 2007, Porto, Portugal.
Poster
2003
(2003): Individuenbasierte Modellierung in der Ökotoxikologie am Beispiel von Chaoborus crystallinus. Vortrag, SETAC GLB-Jahrestagung, 21-23 September 2003, Heidelberg, Germany. Bis hier in DB korrigiert
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