Anthracene Adsorption to Particles and Water-Stable Aggregates of Mangrove Sediment in Jiulong River Estuary, China

Polycyclic aromatic hydrocarbons (PAHs) pollution in mangroves has drawn much attention, but knowledge of the sorption of PAHs in mangrove sediment is limited. This study investigated the particles and water-stable aggregates (WSA) of mangrove sediment in Jiulong River Estuary, China, and the characteristics of anthracene adsorption to them. The adsorption of anthracene was strongly influenced by the physicochemical and structural properties of sediment particles and WSA. The main sorbents of mangrove sediment were carbonized particles and clays. The porous structure of carbonized particles made it easy to sequestrate sequester the anthracene, and the aging allowed anthracene to move into deeper sites of the carbonized particles. Clays had high anthracene-fixing capacities, and they included organic matters and formed aggregates. The sorption contents coefficient Kf of anthracene with WSA of different sizes increased in the order 0.063 - 0.25 mm > 0.063 mm > 0.25 - 1.0 mm > 1.0 mm. The order was correlated with which due to the contents and characteristics of organic matters in the aggregates.