A general framework for combining ecosystem models

Michael A. Spence, Julia L. Blanchard, Axel G. Rossberg, Michael R. Heath, Johanna J. Heymans, Steven Mackinson, Natalia Serpetti, Douglas C. Speirs, Robert B. Thorpe, Paul G. Blackwell

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

When making predictions about ecosystems, we often have available a number of different ecosystem models that attempt to represent their dynamics in a detailed mechanistic way. Each of these can be used as a simulator of large-scale experiments and make projections about the fate of ecosystems under different scenarios in order to support the development of appropriate management strategies. However, structural differences, systematic discrepancies and uncertainties lead to different models giving different predictions. This is further complicated by the fact that the models may not be run with the same functional groups, spatial structure or time scale. Rather than simply trying to select a 'best' model, or taking some weighted average, it is important to exploit the strengths of each of the models, while learning from the differences between them. To achieve this, we construct a flexible statistical model of the relationships between a collection of mechanistic models and their biases, allowing for structural and parameter uncertainty and for different ways of representing reality. Using this statistical meta-model, we can combine prior beliefs, model estimates and direct observations using Bayesian methods, and make coherent predictions of future outcomes under different scenarios with robust measures of uncertainty. In this paper we take a diverse ensemble of existing North Sea ecosystem models and demonstrate the utility of our framework by applying it to answer the question what would have happened to demersal fish if fishing was to stop.
LanguageEnglish
Pages1031–1042
Number of pages12
JournalFish and Fisheries
Volume19
Early online date15 Aug 2018
DOIs
Publication statusPublished - 24 Oct 2018

Fingerprint

ecosystems
ecosystem
prediction
uncertainty
parameter uncertainty
mechanistic models
Bayesian theory
statistical models
North Sea
demersal fish
learning
functional group
simulator
fishing
timescale
experiment

Keywords

  • ecosystem modelling
  • marine ecosystems
  • Bayesian

Cite this

Spence, M. A., Blanchard, J. L., Rossberg, A. G., Heath, M. R., Heymans, J. J., Mackinson, S., ... Blackwell, P. G. (2018). A general framework for combining ecosystem models. Fish and Fisheries, 19, 1031–1042. https://doi.org/10.1111/faf.12310
Spence, Michael A. ; Blanchard, Julia L. ; Rossberg, Axel G. ; Heath, Michael R. ; Heymans, Johanna J. ; Mackinson, Steven ; Serpetti, Natalia ; Speirs, Douglas C. ; Thorpe, Robert B. ; Blackwell, Paul G. / A general framework for combining ecosystem models. In: Fish and Fisheries. 2018 ; Vol. 19. pp. 1031–1042.
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Spence, MA, Blanchard, JL, Rossberg, AG, Heath, MR, Heymans, JJ, Mackinson, S, Serpetti, N, Speirs, DC, Thorpe, RB & Blackwell, PG 2018, 'A general framework for combining ecosystem models' Fish and Fisheries, vol. 19, pp. 1031–1042. https://doi.org/10.1111/faf.12310

A general framework for combining ecosystem models. / Spence, Michael A.; Blanchard, Julia L.; Rossberg, Axel G.; Heath, Michael R.; Heymans, Johanna J.; Mackinson, Steven; Serpetti, Natalia; Speirs, Douglas C.; Thorpe, Robert B.; Blackwell, Paul G.

In: Fish and Fisheries, Vol. 19, 24.10.2018, p. 1031–1042.

Research output: Contribution to journalArticle

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AU - Spence, Michael A.

AU - Blanchard, Julia L.

AU - Rossberg, Axel G.

AU - Heath, Michael R.

AU - Heymans, Johanna J.

AU - Mackinson, Steven

AU - Serpetti, Natalia

AU - Speirs, Douglas C.

AU - Thorpe, Robert B.

AU - Blackwell, Paul G.

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Spence MA, Blanchard JL, Rossberg AG, Heath MR, Heymans JJ, Mackinson S et al. A general framework for combining ecosystem models. Fish and Fisheries. 2018 Oct 24;19:1031–1042. https://doi.org/10.1111/faf.12310