Study On The Relationship Between Estuarine Eutrophication And Red Tide Ecology

From studying on aquatic biology to studying on ecological modeling; from physical process research to biological process research; up to present time, studying on coupling physical processes and ecological processes of organisms, study on estuarine ecosystem has been developing for hundreds of year. The domain of ecosystematic research is divided into many branches of subject. The scale of ecological model will be from small to large. The content of ecological model will be extensive and profound. In resent years, red tide occurs frequently to estuarine water area. On the bases of WASP5 (U.S. environmental protection agency, 1993), the paper sets up a coupling model, which combines WASPS with nutrient dynamics modeling on red tide. The network of hydrodynamic model is characteristic of junction-channel, which physical meaning is in focus and simple. The structure of junction - channel network is extended to two-dimensional or three-dimensional network conveniently. Eutrophication model is characteristic of one-dimensional and two-layers' model, and the mixed layer has transport processes with benthic layer. The ecological essential and biological essential of eutrophication through water is presented. From the point of view, how the eutrophication is formed is calculated in model. On the bases of nutrients dynamics and food chain principles, Red tide nutrients dynamic model describes the process of propagation and contabescence on red tide. The coupling model is applied to study ecological environment on Pearl River Estuary. The standard of eutrophication is estimated and probability of red tide' s occurrence is predicted. Upon this, the dialectical relation between red tide and eutrophication is thoroughly discussed.