Exploring, exploiting and evolving diversity of aquatic ecosystem models: a community perspective

Abstract

Here, we present a community perspective on how to explore, exploit and evolve the diversity in aquatic ecosystem models. These models play an important role in understanding the functioning of aquatic ecosystems, filling in observation gaps and developing effective strategies for water quality management. In this spirit, numerous models have been developed since the 1970s. We set off to explore model diversity by making an inventory among 42 aquatic ecosystem modellers, by categorizing the resulting set of models and by analysing them for diversity. We then focus on how to exploit model diversity by comparing and combining different aspects of existing models. Finally, we discuss how model diversity came about in the past and could evolve in the future. Throughout our study, we use Handling Editor: Piet Spaak.Electronic supplementary material The online version of this article (doi:10.1007/s10452-015-9544-1) contains supplementary material, which is available to authorized users. 123Aquat ) 49:513-548 DOI 10.1007 analogies from biodiversity research to analyse and interpret model diversity. We recommend to make models publicly available through open-source policies, to standardize documentation and technical implementation of models, and to compare models through ensemble modelling and interdisciplinary approaches. We end with our perspective on how the field of aquatic ecosystem modelling might develop in the next 5-10 years. To strive for clarity and to improve readability for non-modellers, we include a glossary.

Challenges associated with modeling low-oxygen waters in Chesapeake Bay: a multiple model comparison

“…This finding is similar to that of other studies that examined the value of the Model Mean from a multi-model ensemble (e.g., Gneiting and Raftery, 2005;Hagedorn et al, 2005). While the concept of using a multi-model ensemble has been most extensively employed by atmospheric, climatic, and global circulation modelers, such as the Intergovernmental Panel on Climate Change (e.g., Collins et al, 2013), the tool's utility for aquatic ecosystem modeling is gaining traction (Meier et al, 2012;Trolle et al, 2014;Janssen et al, 2015). As models are increasingly used in regulatory decisions regarding aquatic ecosystems, a cohort of similarly skilled models can be used to help inform a set of confidence bounds around an environmental forecast.…”

Climate Change Will Make Recovery from Eutrophication More Difficult in Shallow Danish Lake Søbygaard

“…Thus, it is possible to estimate the magnitude of nutrient reduction required in a future warmer climate to mitigate eutrophication in order to achieve good ecological status as required by the WFD. However, it is important to continuously improve the conceptual model, and also to take advantage of the diversity of multiple existing models [85], to enhance the reliability of projections, such as, for example, the submodels for fish, fish-zooplankton interactions and sediment nutrient exchange.…”

Coupling Water Column and Sediment Biogeochemical Dynamics: Modeling Internal Phosphorus Loading, Climate Change Responses, and Mitigation Measures in Lake Vansjø, Norway

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