Investigating the physicochemical conditions of the Caspian Sea water in Sisangan region for setting up a Salmon breeding farm in a cage

In general, increasing the production and exploitation of aquatic animals in the aquatic ecosystem without considering its relationship and balance with other parts of the ecosystem causes a wrong assessment of the real cost and benefits of these services to the environment and society, and in the future will have negative effects. The activities carried out in the aquaculture industry lead to a decrease in the quality of water and as a result the chemical balance in water is disturbed. On the other hand, the increase in metabolic activity in aquatic animals intensifies those effects. In the aquaculture industry, attention should be paid to quality control and monitoring methods. Knowing the basic conditions of the desired water body for the construction of breeding farms and predicting the future situation of the region based on the effluents entering is very necessary.

In this study, the physicochemical conditions of Sisangan region were investigated for setting up a fish farm.

In order to determine the state of sea water quality, water sample collected for one period to analyze pollution and physicochemical variables. After determining of the variables, the TRIX trophic index was calculated and the trophic conditions of the area were determined.

Measuring the physical parameters of water from 5 to 15 meters depth showed that the variables of temperature, electrical conductivity, salinity, oxygen and pH do not change much along the depth. The measurement of nutrients indicated that the total nitrogen in the sea in the study area varies from less than 0.1 mg/liter to 2.5 mg/liter. The amount of total phosphorus in the study range varies from less than the measuring limit of the device 0.003 mg/liter to 0.007 mg/liter. According to the measurements made in these studies, the result of calculating the TRIX index is an average numerical value of 2.3.

The results of this study showed that the area is tropically oligotrophic and the water quality of the area is very good.