Distributions of Dissolved Forms of Manganese and Iron in the Water Column of the Southeastern Black Sea

Dissolved forms of manganese and iron elements and some physical parameters in the water column of the Southeastern Black Sea were investigated. Samples were collected from 14 different depths of the water column in the station. Sea Bird SBE 25 Sealogger CTD was utilized for measurement of temperature, salinity, sigma-t and conductivity. However, Winkler method was used tor dissolved oxygen measurements. Also, hydrogen sulphide was determined by using the titration method. Dissolved iron and manganese were analyzed with GBC 905 FAAS after pre-concentration of MIBK. The Black Sea water surface temperature, salinity and oxygen were recorded as 16.23 +/- 6.87 degrees C, 17.80 +/- 0.23 S parts per thousand and 289.68 +/- 47.66 mu m, respectively. The concentration of oxygen decrease to 10 mu m and H2S was recorded as 5 mu m when the water column depth was 150 m depth. It was seen that the H2S concentration increased depending on depth and it reached to 155.22 +/- 11.81 mu m in 600 m depth. It was observed that the iron and manganese metals concentration clearly increased in depths at which oxygen consumed and hydrogen sulphide appeared. It was confirmed that the evaluation of many parameters in the Black Sea water column depending on sigma-t was more suitable than that depth profile. The behavior of trace metals were considerably influenced by conditions with hydrogen sulfide and without oxygen.