Effect of Lessonia Trabeculata algae extraction, Villouta and Santelices 1986, on the macrobenthos in Marcona, Peru

Abstract

Macroalgae are dominant organisms in cover and biomass in cold and temperate seas of the rocky shores worldwide. The overexploitation of the resource endangers two important aspects: 1) it is allowing no proper renewal of natural pastures and 2) be affecting macrobenthic communities. The aim of this work was determined the effect of the removal Lessonia trabeculata on the richness and abundance of macrobenthos associated to algae in Marcona. Sampling in 02 sectors (Lobo Fino and Basural), in each 03 transects with 03 stations distributed in depth intervals were located was performed: 5-10 m, 10-15 m and 15-20 m, obtaining a total of 18 holdfasts as samples and 9 between disk. A total of 5399 organisms grouped in 71 different species were recorded, identifying 5369, corresponding to 31 species of Phylum Annelida, 17 to Mollusca, 15 to Crustacea, 4 to Equinodermata, 1 to Tunicata, 1 to Nemertea, 1 to the Pycnogonida and 1 to the ichthyofauna of the sector. The species richness (S) on the discs varied between 13 and 37 being the P.3.2 and P.3.3 substations of Lobo Fino with higher values, while among the S evidenced between disks varies from 8 to 24, with higher registration of I.4 station of Basural. The cluster analysis performed with PRIMER 6.0 gives us the result that between the substations of Basural exists a similarity of 61% being B.4.3 substation which differs in one group the highest species richness of polychaetes and between substations of Lobo Fino to 62% L.1.1 and L.1.2 substations are separated by differences in diversity of molluscs and crustaceans.