Global patterns of macroinvertebrate production in marine benthic habitats

Using data published in 15 major marine ecology journals (from 1970 to 1999), we examined global patterns of marine benthic macroinvertebrate production and its distribution among feeding guilds and taxonomic groups and physical variables such as substratum type, water depth and temperature. Our database contains 547 production datasets, from 147 studies including 207 taxa, assessed by classical methods (cohort and size-based methods), from 170 sites (77°50'S to 69°35'N; 0 to 930 m depth). In general, higher values of production to biomass (P/B) ratios were observed in the Northern Hemisphere than in the Southern Hemisphere. High values of P/B ratios were observed in mid-latitudinal zones while low values of P/B ratios were observed in high (80 to 60°S) and low latitudinal zones (40°S to 20°N). Highest production was observed on hard substrata, for filter feeders and for mollusc (e.g. bivalves) species. Highest P/B ratios were observed on algae (or high organic substrata), omnivores and predators, and arthropods (e.g. amphipods). Regression models explained a significant percentage of the amount of variance of benthic production (92%) and P/B ratios (50 to 86%). Production and P/B ratios were negatively related to water depth and positively related to water temperature, but these abiotic variables did not greatly improve the predictability of production by biotic variables (e.g. life span, mean body mass). Biotic variables were more important than environmental variables in explaining observed variations in production and P/B ratios. For the latter, life span explained most (45 to 83%) of the variation of the models.