On the distribution of dissolved hydrocarbons in natural water

The identity and form of dissolved organic matter in rivers and oceans are fundamental to the biogeochemical cycle of carbon. In particular, understanding the phase distribution of hydrocarbon compounds is a prerequisite to predicting the transfer between phases and the impact of anthropogenic inputs of fossil fuels to the aquatic environment. After rigorous blank-correction of each individual hydrocarbon component of dissolved and particulate hydrocarbon samples from the Mackenzie River, we obtained dissolved hydrocarbon measurements that were unquestionably above the mean blank. Equivalence of the dissolved and particulate hydrocarbon compositions indicates that the two fractions are coupled or at equilibrium in natural waters. Changes in individual hydrocarbon concentrations with sample volume suggest that the dissolved hydrocarbons may be distributed fractally in water.