Effects of shrimp trawling on the structure of macrobenthic communities of Paraná's inner shelf
Data de publicação: 30/10/2007
The objective of present contribution was analyzes disturbances caused by shrimp trawling on macrobenthic communities of soft bottom on two areas: one located within a currently trawled area and the other impacted in the past by trawling activity, but where supposingdly there is no trawling in the present. Samples were taken using an iron core of 0.05 m² with a 500µm mesh attached to one of the core ends received the collected material by SCUBA diving. Bi-factorial analysis of variance (MANOVA) was performed to compare ecological descriptors for both areas. To analyze and compare the communities’ structure was performed a MDS and similarity analyses (ANOSIM). It is not found significant difference for anything ecological descriptor, nor to the total of polychaetes, bivalves and crustaceans between areas. However, significant differences were found among months, except to the total of bivalves and Shannon & Wiener diversity index, indicating that differences were more related to temporal variation than to area variation.