A seasonal analysis of the southern North Sea ecosystem

Developed an input-output model of the S North Sea ecosystem in order to determine the relationships between 10 biotic and abiotic stock levels and to investigate how their direct and indirect dependency changed through the typical year. The method captures not only the food source connection but also those species that contribute to the food source, those at the next level that contribute to those sources, and so on, until all the exchanges have been assigned without ambiguity. The method even captures the indirect connection that a species may have to itself. The authors followed the fate of absorbed solar energy to trace the connections between the elements of this ecosystem. Sensitivity analysis showed which of the direct and indirect interconnecting flows is most affected by the rate of fish removal. The model also shows where specific management intervention (eg, "fertilization') would be the most efficient in allowing stable system responses to fishing rate increases. -from Authors