An Integrated Modelling Approach to Environmental Quality Management

Abstract

The theme of this paper concerns the role of models in integrating research across disciplinary boundaries and their use as an aid to environmental quality management. It adds too the contribution made by Radford et al., in the EBSA Local Meeting on the Tamar Estuary (April 1982) but concerns a different application of the same principles.

Biochemical Oxygen Demand (BOD) models have long been established as a management tool and have been used most effectively in monitoring the recovery of a number of grossly polluted estuaries. Their limitations in predicting oxygen levels in cleaner environments has always been acknowledged, but attempts to include the contribution of primary producers have been limited and largely unsuccessful. Ecological models such as GEMBASE (General Ecosystem Model of the Bristol Channel and Severn Estuary) have tended to be regarded as rather esoteric and certainly too theoretical for practical estuarine management. Recent work at IMER has been concerned with the integration of the best features of both BOD and ecosystem models into a single model which is capable of predicting the transition of a highly polluted estuary into a near normal ecosystem and vice versa. This work, which has been done in collaboration with the Hydraulics Reseach Laboratory has used a three-dimensional hydrodynamic model to compute exchanges between system elements of dissolved and planktonic components of the estuary. A classical BOD model based upon research from the Water Research Centre (Stevenage) has been developed to compute oxygen concertrations but a ecosystem model based on GEMBASE interacts with both of these models to allow for the impact of the living components. Thus two types of model which have always been considered as incompatible have been integrated to produce a practical management tool.