study on accumulation of heavy metals in mangrove sediments, gabrik creek (jask)

gabrik in the east of hormozgan province is mangrove habitat and one of the important mangrove protected area. this area is located in oman coasts. this zone because of building jagin dam on gabrick river and existence of sand barrier and exposure of pollution, it is possible to destroy or to be important threats of this planet. base on importance of this sea inhabitation some of sedimentology parameters and geochemical mangrove's sediments have been analyzed. in this study for sieve used hydrometric method and for identification of organic matter used electronic furnace heat 500 degree centigrade for 6 hours. quantity of calcium carbonate analyzed by titration and for condenses of heavy metal zn, pb and ni chemical decomposition atomic absorption by thermo-solaar (±1µg/g). results showed that mean content of carbonate and organic matter in the sediments is 27%and 3.36% respectively. contamination heavy metals pb, zn and ni in the sediments of this mangrove, were studied throughout gabrik creek. metal concentration analyses were performed using atomic absorption spectrometry (aas). mean concentration of the heavy metals pb, zn and ni in sediments was measured 67.63, 69.63 and 76.53 µg/g dry weights respectively. according to determine geoaccumulation index (igeo), contamination factor (cf), the degree of contamination correction (mcd) and compared the heavy metal concentrations with to the mean concentrations of heavy metals in sedimentary rock (shales) and china and american standards. the results in this study showed that there is no pollution from zn metal but there are pollutions from ni and pb metals and concentration this heavy metals aren't critical. the origin of these heavy metals can be a result of maintenance of fishing vessels in gabrik creek, activities or fuel smuggling and perhaps oil compounds spill into the water and human refuse in the region.