Effects of sewage pollution on the structure of rocky shore macroinvertebrate assemblages

Abstract

The urgency to find efficient indices and indicators to prevent further deterioration of coastal areas is one of the hot topics in today's scientific publication. However, a detailed knowledge of community responses to anthropogenic impacts is essential to sustain those indices. The studies on the response of benthic community to sewage pollution on intertidal rocky shores are generally based on visual census and do not take into account the tidal levels. In order to fulfil this gap in this study: (i) the sampling was performed by destructive sampling, with all individuals identified to the species level; (ii) the sampling was done at all levels of the intertidal (sublittoral fringe, eulittoral, and littoral fringe). Sewage pollution changed the environmental variables and the abundance of macroinvertebrates, being Mytilus galloprovincialis, Melarhaphe neritoides, and Chthamalus montagui the species most responsible for the dissimilarities observed. Effects were different on the three intertidal zones: community structure changed in the sublittoral fringe; suspensionfeeders abundances and species richness increased in the eulittoral; no differences were detected in the littoral fringe. Moreover, the results confirm that the presence of sewage discharges tended to benefit suspension feeders, and that the sensitive species were replaced by opportunistic ones.

Ability of invertebrate indices to assess ecological condition on intertidal rocky shores

“…Also, this dominance of filter-feeders, which are ecological engineers, can increase the habitat availability and some increased richness could take place. This was reflected in the communities found at this time which, like other European intertidal rocky shores, are composed of a high number of species and richness (in number of species) was in some cases positively influenced by intermediate disturbance (e.g., Archambault et al, 2001;Magurran and McGill, 2010;Bustamante et al, 2012;Díez et al, 2012;O'Connor 2013;Cabral-Oliveira et al, 2014;Vinagre et al, 2016). Despite such high richness, communities along such rocky shores are usually dominated by few species, namely barnacles and mussels (both filter-feeders and space occupiers), which appear naturally in dense assemblages and account mostly for the densities and biomass found there (e.g., Boaventura et al, 2002;Araújo et al, 2005;Pereira et al, 2006;Vinagre et al, 2016).These might be the reasons for the higher agreement observed between composition indices and the MarMAT, when compared to indices based on abundance/diversity data, and the better performance shown by indices calculated using biomass data, compared to those calculated using density.…”

Arsenic accumulation in intertidal macroalgae exposed to sewage discharges

“…Although there are no statistically significant differences, other parameters (seawater temperature, pH) revealed changes (Cabral-Oliveira et al 2014). This occurs due to the dilution in the marine water and because the discharges are not continuous.…”

Distinguishing globally-driven changes from regional- and local-scale impacts: The case for long-term and broad-scale studies of recovery from pollution

“…India, Africa) remain slow. -Oliveira et al, 2014;Corcoran et al, 2010;Costanzo et al, 2001;Costello and Read, 1994;Hawkins et al, 1999;Islam and Tanaka, 2004;Kennish, 2002;Littler and Murray, 1975 Oil spills     Accidents on rigs and ships.…”