THE ARTHROPOD COMMUNITY, ESPECIALLY CRUSTACEA, AS A BIOINDICATOR IN ALGECIRAS BAY (SOUTHERN SPAIN) BASED ON A SPATIAL-DISTRIBUTION

Spatial variation of the arthropod communities of the alga Halopteris scoparia in relation to the influence of environmental factors in the Algeciras Bay (Southern Spain) was investigated by means of multivaria te analyses. We have been able to determine a clear separation in comp osition of communities between external and internal areas of the bay, with hydrodynamism and algal morphology being the most determinant fa ctors. In the external zone a greater number of species appear, whose quantitative dominances are more even than among the species of the in ternal zone, where some clearly dominate over the others, e.g., the am phipods Corophium acutum and Jassa marmorata. Crustaceans show in a cl ear way the differences among the localities and are useful in charact erization studies of environmental quality of coastal waters because o f the abundance, high species richness and the wide environmental spec trum in the epiphytic communities.