Distribution and community structure of the benthic macroinfauna at the coast of northern Chile

The community structure of the intertidal and subtidal macroinfauna was stu died at the littoral of northern Chile, a coast characterized by the freque ncy of upwelling. Thus, samplings were carried out at the coast of Antofaga sta, Caldera and La Serena - Coquimbo. The community structure of the inter tidal macroinfauna of sandy beaches showed relations with the morphodynamic beach characteristics; at beaches with reflective characteristics (coarser grains, steeper slopes) occurred the lowest number and abundance of taxa. The opposite was found at beaches with finer grains and gentler slopes (int ermediate beaches). Ir was also found a latitudinal replacement of species, primarily at the upper intertidal levels. At the subtidal bottoms, the var iability of sedimentological characteristics, species richness, abundance, biomass and secondary production of the macroinfauna allowed to diferenciat e bays and specially between deep (50 - 65 In) and shallow bottoms (15 - 20 m). While the first ones were characterized by finer sediments and polycha etous dominance, the second ones had coarser sediments with a higher repres entation of crustaceans and molluscs. The estimated Values of secondary pro duction were relatively low, considering that this region is subjected to c oastal upwellings which are inducing high levels of primary productivity.