摘要 : The transformation of chlorophyll a by two benthic bivalves - Dreissena polymorpha and Mytilus edulis and, for comparison, by the chironomid Chironomus plumosus - was examined. D. polymorpha is a suspension-feeding, freshwater but... 展开 The transformation of chlorophyll a by two benthic bivalves - Dreissena polymorpha and Mytilus edulis and, for comparison, by the chironomid Chironomus plumosus - was examined. D. polymorpha is a suspension-feeding, freshwater but very salinity-tolerant species, M. edulis a suspension-feeding marine species, and C. plumosus a typical detritivorous freshwater species. All three are common in the Odra Estuary. Specimens of the three species were collected from this area in the period 1999-2003. The bivalves were transferred to a compartment on land and kept in tanks filled with water (filtered and unfiltered) collected simultaneously with the organisms, under light and temperature conditions similar to those obtaining in their natural environment. Pigments in the water samples, faeces and pseudofaeces from the tanks, and in the gut content from C. plumosus, were determined with HPLC. The digestion products of the three species were mainly phaeophorbides a, generally thought to originate mainly from zooplankton grazing, and pyrophaeophytin a in minor quantities. The results indicate that the main chlorophyll a derivatives in faeces and pseudofaeces and gut content of the three species were the same as those in the sediments of the Baltic Sea, including the Odra Estuary. Our previous studies have shown that the sediments in this area are richer in phaeophorbides a than sediments from other parts of the southern Baltic Sea. All this suggests that the benthos may play an important role in the transformation of chlorophyll a in the Odra Estuary area. 收起