Hidrocarbonetos e esterois como indicadores de fontes e destino de matéria orgânica em sedimentos da Baía de Sepetiba, Rio de Janeiro

Abstract

Recebido em 15/9/08; aceito em 11/3/09; publicado na web em 4/8/09 HYDROCARBONS AND STEROLS AS INDICATORS OF SOURCE AND FATE OF ORGANIC MATTER IN SEDIMENTS FROM SEPETIBA BAY, RIO DE JANEIRO. The inputs of organic matter derived from natural and anthropogenic sources to Sepetiba Bay were investigated by using aliphatic hydrocarbons and sterols in superficial sediments. Concentrations ranged from 0.26 to 2.65 μg g -1 , <0.01 to 17.41 μg g -1 and 0.77 and 9.24 μg g -1 for n-alkanes, UCM (unresolved complex mixture) and total sterols, respectively. The selected markers and ratios among individual compounds showed the major contribution of terrestrial sources to the total pool of sedimentary organic matter in the bay, but the accumulation of autochthonous organic matter increased with distance from the shoreline. The input of petroleum hydrocarbons and sewage (coprostanol in the range 0.01 to 0.43 μg g -1