Majid Abbaspour Tehrani Fard - Professor, Sharif University of Technology, Tehran, Iran
Elahe Zohdi - M.Sc. in Civil Engineering, Sharif University of Technology, Tehran, Iran

The red tide, or algae bloom, occurs due to the rapid accumulation of algae in the water column, saline water or freshwater, and in high densities. It changes the color of water in green, yellow, brown or red, has a massive impact on general health Fishing and tourism. The areas with specific climate and geographical conditions and the limited exchange of water with the environment in recent years have faced this phenomenon. The recent widespread and continuous expansion of the Red Sea in the Persian Gulf has had irreversible effects on the ecosystem and the economic conditions and general health of its inhabitants, and as a result the need for understanding this phenomenon has become increasingly important. Among the methods of studying this phenomenon, numerical modeling is less important due to time and cost, among which Mike s software, due to consideration of the physical, chemical and hydrodynamic aspects of the sea, and the biological aspects of the phenomenon and the effect of factors Temperature, salinity and nutrients on its growth and progression are used in this paper. In this paper, the effect of input and hydrodynamic contamination of the Persian Gulf flows on the progression of the Red Trench during the 2009-2009 and Chlorophyll-A soluble Oxygen Changes were simulated using two MIKE21 modules and a ECOLAB-1 Eutrophication model. The simulation results showed that the direction of the phenomenon is in accordance with the direction of the current flow on the Gulf, and also the chlorophyll-A concentration is higher near the sources of wastewater discharge, and at all times the presence of nutrients in those areas is persistent. Also, with increasing chlorophyll-A, the concentration of dissolved oxygen increases.

Red tide, Karlodinium, Hobbes, Algae flourishing, Chlorophyll-A, Mike21