MACROLNFAUNAL COMMUNITIES OF SHALLOW TROPICAL SOFT BOTTOMS (COLOMBIAN CARIBBEAN)

Abstract

With the aim to charactenze the soft-bottom macrofauna and its spatial and tomporal distnbution patterns in the Santa Marta area, a two years sampling program was performed at depths between 7 to 60m Density, biomass and diversity of tho community woro dotorminod. Tho BIOENV method was applied in order to relate the distnbution of the associations and the environmental vanables (depth, turbidity, organic matter, organic carbon, organic nitrogen, organic phosphorus and median particle diamotor). A density of 1499 indiv * m, and 10.9 g * m* wot biomass woro obtainod. Tho collected organisms belonged to six taxa; polychaetes. crustaceans, sipunculids, molluscs, bryozoans, and ccfunoderms; the first ono was tho most important in terms ol abundance and biomass. Four Ousters were obtained following a depth gradient, but no clear temporal pattom became evident. Due to a targe number ol generalist gonora among the dusters, a sole community conformed by several zones with diffuse boundanos was defined Depth is the vanable which better oxpiams tho distribution of the community; the correspondng correlation coefficient was high in companson with othermacrobenthos studies earned oul *1 the Canbbean as well as m temperate, unpoilutod areas. In the Caribbean. depth alone, or with other variables, exhibits the best relationship with tho biological structural paneros.