The bivalves Amarilladesma mactroides and Donax hanleyanus as bioindicators of the impact of vehicles on Cassino Beach, southern Brazil.

Sandy beaches are the main recreational ecosystems of the world, enabling high ecological impacts, especially on the benthic macrofauna, which inhabit the sandy matrix and have a low capacity of locomotion. Cassino Beach, located in southern Brazil, has intense vehicle traffic during the summer, so the purpose of this study was to evaluate the impact of vehicles on the key species Amarilladesma mactroides and Donax hanleyanus. For this purpose, samplings were performed in three sectors of this beach (High Impact, Moderate Impact and Control) during six periods of the year.

Determination of trace elements in Sergio mirim: an evaluation of sample preparation methods and detection techniques.

In this work, some trace elements (As, Cd, Cr, Cu, and Pb) were determined for the first time in the crustacean Sergio mirim (Decapoda: Thalassinidea: Callianassidae) from Southern Coast (Rio Grande, RS) of Brazil. The trace element determination was carried out by graphite furnace atomic absorption spectrometry (GF AAS) and inductively coupled plasma mass spectrometry (ICP-MS). Different microwave radiation-based sample digestion methods were evaluated.

The impact of short-term depositions of macroalgal blooms on widgeon-grass meadows in a river-dominated estuary.

Macroalgal blooms can trigger adverse biogeochemical conditions at the sediment-water interface of shallow coastal areas, hence threatening critical habitats such as seagrasses meadows. The direction and magnitude of macroalgal blooms impacts on the aquatic ecosystem can be context-dependent, varying according to the local hydrodynamic conditions. Thus, studies investigating the impacts of stagnant algal depositions on the benthos may fail to address realistic situations and interactions which are common in well-flushed systems.