Publication Date:
2022-05-23
Description:
Energy flow and material cycling in aquatic environments can be conceptualized in terms of food webs, linking various taxonomic or functional biological compartments and their physical environment. Interpretation of empirical data and finally a functional understanding of the system studied requires a high degree of abstraction and aggregation. The complexity and variability of environmental systems, the scarcity of appropriate observations and experiments, and the lack of a weil established theoretical background make it difficult to test any possible conceptualization, or hypothesis, describing a given system. A formal approach to hypothesis testing, based on numerical simulation, which explicitly considers the above constraints, is proposed. Based on a data set from the North Sea, a series of hypotheses on the structural relations and the dynamic function of the pelagic food web is formulated in terms of numerical models. Hypotheses of various degrees of aggregation and abstraction are tested by comparing singular statements (predictions) deduced from the proposed hypotheses (the models) with the observations. The basic processes of primary production, consumption, and remineralization, driven by light, temperature, and advection/diffusion, are described in systems models ranging in complexity from two compartments to many compartments and species groups. With each of the proposed models, a yearly cycle of the systems behavior is si mulated. The comparative analysis of the response of each of the models allows conclusions to be drawn on the adequacy of the alternative hypotheses. This analysis also allows one to reject inadequate constructs, and provides some guidance on how to improve a certain hypothesis, even in the presence of a high degree of uncertainty.
Type:
Article
,
NonPeerReviewed
Format:
text
Permalink