The impact of sewage on environmental quality and the mesozooplankton community in a highly eutrophic estuary in Argentina

Abstract

Dutto, M. S., López Abbate, M. C., Biancalana, F., Berasategui, A. A., and Hoffmeyer, M. S. 2012. The impact of sewage on environmental quality and the mesozooplankton community in a highly eutrophic estuary in Argentina. – ICES Journal of Marine Science, 69: 399–409. Eutrophication caused by human sewage is a growing phenomenon along coasts. Mesozooplankton abundance, community structure, and environmental quality were compared at two sites in the inner Bahía Blanca Estuary (BBE), Argentina, one receiving regional sewage discharge (Canal Vieja), and the other a non-impacted area (Bahía del Medio). Comparisons of mean abundance and multivariate analyses were performed to detect spatial and temporal variations in both environmental and biotic variables. Significantly higher amounts of nitrogen and phosphorus and lower oxygen and pH were recorded at Canal Vieja. Larvae of the detritivorous crab Neohelice granulata were more abundant at Canal Vieja, whereas the common estuarine copepod species Acartia tonsa was more abundant at Bahía del Medio, where the mesozooplankton community was typical for the estuary. Although mesozooplankton is likely to be adapted to the high organic matter content in the BBE, the environmental conditions at Canal Vieja appear to favour Neohelice granulata, and this species should be considered as a potential indicator of the impact of sewage in future monitoring programmes. Particulate organic carbon and chlorophyll a were not influenced by organic loading in this naturally eutrophic estuary.

Tidal effects on short-term mesozooplankton distribution in small channels of a temperate-turbid estuary, Southwestern Atlantic

“…It also receives most of the direct effect of continental run-off, regional sewage discharge and freshwater flow from the Napostá Grande creek, probably explaining the lower salinity observed there than that in BM. The pH values found at both sites were consistent with data from other research carried out in the inner zone of the estuary POPOVICH et al, 2008;DUTTO et al, 2012, SPETTER et al, 2014.…”

“…It is considered unpolluted (HOFFMEYER; BARRÍA, 2007), has no direct connection to the main channel and is part of a system of channels forming a loop completely surrounded by a large extension of marsh (GINSBERG; ALIOTTA, 2011). A number of studies carried out in recent years have provided considerable background information and data on environmental features such as temperature, salinity, pH, oxygen, particulate organic matter and on the zooplankton characteristics of both channels (BALDINI et al, 1999;TOMBESI et al, 2000;BARRIA, 2007;MARCOVECCHIO et al, 2008;DUTTO et al, 2012).…”

“…Tides, winds and estuarine circulation influence the composition and abundance of estuarine zooplankton, also affecting zooplankton assemblage composition and therefore their spatial (vertical and horizontal) distribution (HILL, 1991;WIAFE;FRID, 1996;DAUVIN et al, 1998;KIMMERER et al, 1998KIMMERER et al, , 2002PEITSCH et al, 2000;ROMAN et al, 2001;MOUNY;DAUVIN, 2002;NAYLOR, 2006;THORISSON, 2006;DEVREKER et al, 2008DEVREKER et al, , 2010HSIEH et al, 2010;UEDA et al, 2010;SCHMITT et al, 2011;MENENDEZ et al, 2011MENENDEZ et al, , 2012GONÇALVES et al, 2012;DA COSTA et al, 2013). The temporal variation in environmental conditions is another main factor strongly affecting the occurrence, features and distribution of zooplankton assemblages (DAUVIN et al, 1998;MARQUES et al, 2009;DUTTO et al, 2012). The vertical distribution of plankton is particularly affected by the speed and direction of currents (HILL, 1991).…”

Environmental modulation of the plankton community composition and size-structure along the eutrophic intertidal coast of the Río de la Plata estuary, Argentina

“…For example, anthropogenic perturbations strongly modulate the phytoplankton-community biomass and composition (Paerl et al, 2010), because of its direct link and sensitivity to nutrient loading (Borja et al, 2012). On the other hand, in other estuaries, zooplankton response is predicting to environmental changes like salinity, water temperature, and turbidity (Marques et al, 2008), and some zooplanktonic species should be considered as a potential indicator of the impact of sewage (Dutto et al, 2012).…”

Effect of treated sewage effluents on plant cover and soil at Wadi Al Rummah, Qassim Region, Saudi Arabia

“…Inadequately treated sewage effluent will result in a significant negative impact on the environment (Dutto et al 2012) and public health (Vrijheid 2000;Akpor & Munchie 2011).…”