Formulation and use of practical models for river-quality assessment

摘要: ENVIRONMENTAL AWARENESS and new laws such as pl 92-500 have estab lished improved river quality a major goal of overall basin planning. River may be defined the physical, chemical biological character with regard to its suitability for specified purpose. In this context, con cerns not only observed water in river, but also implies sideration causative phenomena, cluding environmental processes occurring on land, water, air, that are respon sible quality. To achieve minimum environmental, social, economic cost, it is imperative planning decisions and. need management facilities based scientific assessment rather than arbi trary edicts assumptions. Thus, objective evaluate, before fact, beneficial or adverse impacts alternatives river. Once been examined, social costs weighed compared each plan ning alternative. The complexities inherent study large rivers, coupled quantitative description behavior, created great interest mathematical models (referred hereafter models) tools simu lating response vari ables alternative pro posals. dissolved oxygen (do)-biochemical demand (bod) relationships by Streeter Phelps1 generally considered pioneering effort applied modeling. Although do continues subject majority models, other variables receiving creasing attention. subjects range complexity from relatively simple temperature highly complex, long-term eutrophication (Figure 1). concept, provide potential problem solving resource planners managers, pollution control officers, government decision makers. general, however, group has failed accept practical tool, often views modeling considerable mistrust. authors concluded failure trust stems fact many formulated basis sound data nor effectively situations. Similar conclusions cited several investigators, including Mar,2 Lombardo,3 Weber et al.* Velz.5