Submarine outfall and new sewage treatment plant modulate the response of intertidal benthic communities in a SW Atlantic area

JAUBET, MARÍA LOURDES; GARAFFO VALERIA GRISELDA; CUELLO VERONICA GRACIELA; HINES, EMILIANO; ELIAS RODOLFO; LLANOS, ELIZABETH NOEMI

MARINE POLLUTION BULLETIN

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2024

0025-326X

Spatio-temporal responses of the intertidal macrobenthic community to the effects of a submarine outfall (SO)and a new sewage treatment plant (EDAR) were evaluated, analyzing changes in macrofaunal assemblages andcommunity structure. Study was conducted in a SW Atlantic coastal area in 4 stages: BSO (Before the SO), Du(During the construction of the SO), ASO (After the SO start-up) and AEDAR (After the treatment plant start-up).Boccardia proboscidea and Brachidontes rodriguezii contributed most to the differences between all stages at thesite nearest to the discharge point. Number of individuals was highest at BSO and Du. Richness and diversity werelowest at the BSO and highest at the Du. Furthermore, the richness decreased slightly, and the diversity increasedat AEDAR. Evenness was highest at the BSO and AEDAR. The nestedness was the dominant process driving thedifferences between the BSO stage community and the rest of the stages. SO affects the composition and structureof the intertidal macrobenthic community near the outfall area, as organic matter discharge further offshorefavour the development of a more diverse intertidal community, including species sensitive to organicenrichment.