Modeling the interactions between eutrophication and heavy metals processes in inland water bodies

The increased number of anthropogenic pollutant sources after the industrial revolution led to an accelerated transfer of heavy metals to aquatic ecosystems. Heavy metals are significant pollutants that have accumulation, toxic, cancerogenic effects in aquatic ecosystems. Their impacts on aquatic ecosystems and organisms have been investigated in several scientific studies. It is observed that heavy metal pollution affects the aquatic species diversity, i.e. some species disappear and some with high tolerance become dominant. The heavy metals accumulate especially in livers and gills of fish, crabs, shellfish etc. and enter the food web. The transport, dissolution, precipitation, complexation, adsorption and bioaccumulation mechanisms of heavy metals are complicated processes that are affected by physicochemical properties of water. Moreover, accumulated heavy metals in sediment are directly or indirectly affected by oxidation and reduction reactions. The eutrophication which is a natural process affect the physicochemical properties of aquatic ecosystems. Thus, the interaction between heavy metal and eutrophication should be determined by the physical, chemical and biological processes that take place in sediment for lake ecosystems. There are many different studies that are taking place which is about heavy metal concentration variation related to eutrophication. These studies are particularly analyzed by the comprehensive literature. It is supported that the determination of the interaction between heavy metal and eutrophication by using mathematical modeling studies. If considered that the laboratory and monitoring studies are long and troublesome processes, calculates mathematical modeling that calculated heavy metal transport, variation, and fate, based on physicochemical and biochemical principle, are required. The aim of this study is setting up a mathematical lake model and calculating the impact of eutrophication on heavy metal in water bodies based on mass balance and energy balance. For this purpose, the developed biochemical model was set up by using Goldsim platform. The model was run and simulated for different scenarios for a completely mixed lake. The developed model was calibrated by using monitoring studies that took place in Beyşehir Lake and streams. Testing the lake model results were evaluated for TN, TP, TOC, chlorophyll-a, temperature, dissolved oxygen parameters, and compatible results were obtained. Whatsmore, the interaction between heavy metals (ferrous and manganese) and eutrophication was calculated with different scenarios. The developed model can calculate species distribution depending on pH and can predict the soluble rate of ferrous and manganese. Consequently, the developed model can express many biochemical and physicochemical processes with the holistic approach that take place in natural aquatic ecosystems. Thus, the pH water, species distribution of pollutants (ionization, dissolution-precipitation balance) can be calculated. The developed model was improved to determine the interaction between eutrophication and heavy metals that suggested a basic platform. Since the model has an open and flexible structure, it can be integrated with different software or can convert a professional program.