A dynamic formulation for input-output modelling of exploited ecosystems

Abstract Exploited ecosystems are similar in many ways to industrial production systems. An extended Leontief input-output model (SIM - Sequential Interindustry Model) that explicitly considers the time required by production processes, and the timing of their inputs, is considered for use in ecosystem modelling. The basics of this dynamic model are presented and then the required modifications for ecosystem application are considered. Human harvest of different species is compared to final demand for industrial goods,, while predation within the ecosystem is viewed as intermediate demand. Special consideration is given to the relationship between members of a species that are consumed at different ages. They are treated as different commodities due to the different history of their inputs. The model is structured to accomodate this need.