Assessment of heavy metals pollution indices in sediments of Tiyab and Kolahi International Wetlands

Heavy metals are pollutants from multiple man-made or natural sources which directly or indirectly enter bodies of water. Therefore, investigation of deposits as metal contaminants is important. The international wetlands of Tiyab and Kolahi are among the most important ecosystems in the south of Iran that due to development programs are polluted by different sources. In order to identify environmental pollution of heavy metals in the sediment of Tiyab and Kolahi, we have collected 22 surface sediment samples from 11 study sites using the Grap Sampler. In order to determine the toxicity and limit pollution index of elements in the sediment, we used the Sediment Quality Standard of America and the Canadian Sediment Quality Standard was used. The results showed that the concentration of heavy metals had the following average ppm: cadmium (6.15), lead (23.22), nickel (142.8) and copper (36.18). The accumulation index of Muller regarding the level of contamination of the area in question indicated that the pollution level of the wetlands was at a medium level. Due to the concentration of heavy metals and the index findings, it could be concluded that cadmium contamination could be related to oil and anthropogenic pollution.