Chitin production by crustaceans in marine ecosystems

Chitin is synthesized by numerous animal species, either unicellular organisms or metazoans, belonging mainly to zoological groups of the Coelomate Spiralia lineage. However, the produced chitin in marine ecosystems is principally by crustaceans. A comparative study of analytical data so far available allowed calculation of chitin biomass and chitin production values in some types of marine ecosystems, and thus estimation of the quantitative importance of chitin in the biogeochemical cycles of carbon and nitrogen. The main data so far available concerns mediterranean plankton in Calvi bay (Corsica), arctic and antarctic krill, lobster population on South African coasts, and infralittoral benthic communities growing on rocky substrates on Corsica coasts. In all these cases, chitin production was estimated roughly at 1g per year and per square meter of rocky substrate or sea surface. Taking into account these production values and the relative extent of the main marine ecosystems over the world, the total production of chitin due to marine crustaceans was estimated at about 2.3 billion metric tons per year.