Spatio-temporal variations of trace elements in sea urchins in Corsica

An assessment of classical and emerging trace element contamination was conducted on gonads of the sea urchin Paracentrotus lividus (Lamarck, 1819), in Corsica (Western Mediterranean). The aim of this study was to evaluate the contamination levels at different sites by following the seasonal variation of 22 trace elements. The sea urchins analyzed were taken in 2017 from reference and more impacted sites in four Corsican areas. The results obtained shown the importance of biotic factors such as gender, reproduction and the way of life. Variations have been highlighted with lower trace element concentrations during the summer season. This is mainly due to a dilution phenomenon resulting from gametogenesis. Moreover, trace elements concentrations varied considerably depending on the location of the sampling stations. This work could provide additional support for other tools for the diagnosis and monitoring of coastal water quality. It provides useful new data to enable managers to act at the source and reduce degradation in order to improve the ecological quality of marine waters.<br />
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Observing strategy: <br />
Sea urchin samples were collected in each season in four Corsican coastal areas between 1 and 5 m depth. In each area, two sites were defined, diverging by their ecological characteristics and their degree of anthropization: a reference site and a site close to identified anthropogenic sources, supposedly impacted. The height, weight, gender and gonadosomatic index of each individual were determined. The trace elements concentrations were then measured.