Modern environmental assessment procedures for enclosed seas

Abstract

Enclosed seas on a world scale are typically characterised by low tidal currents and flushing potential, yet are centres of high population and therefore pollution pressure. Accordingly it is appropriate that recognised environmental assessment procedures are applied. For those examples which have little co-ordinated data, a full baseline environmental investigation is needed to establish a data base against which to measure future change. An appropriate way to achieve this is using an integrated multi-disciplinary approach involving the following components: 1. 1.- review of previous work and collation of existing data. 2. 2.- bathymetric and geomorphologic evolution, and changes. 3. 3.- determination of bottom sediment facies and sediment transport pathways and budgets. 4. 4.- investigation of water column and surficial sediment geochemistry and ecotoxicity. 5. 5.- inlet hydraulics, tidal, current and wave climate measurements. 6. 6.- investigation of marine biology and ecology, and the patterns of eco-distribution in relation to the sedimentologic, oceanographic and pollution parameters. 7. 7.- numerical modelling of current hydrodynamics. 8. 8.- numerical modelling of water quality and pollution dispersion. 9. 9.- numerical modelling of hazards such as tsunamis, storm surge and flooding, and the effect of such events on the enclosed sea hydrodynamics, pollution and sediments. 10. 10.- review of the efficacy of the numerical models in relation to the field and empirical data; i.e. how well do the models fit perceived “reality”? Only by undertaking an integrated, multi-disciplinary study can the best planning decisions be made for future resource utilisation and management of the enclosed seas. Presently such a study is proposed for Osaka Bay, Japan.