Evaluation of the sea water quality of Mostaganem bay through the sea urchin Paracentrotus lividus (Lmk) bioindicator

Abstract

Since the last decade, the use of biological indicators in assessing the quality of the environment has become one of the latest methods in the history of environmental science. Indeed, any human activity (industrial, agricultural or tourism development) cause a very important environmental pressure on coastal marine species assemblage. For this, we chose to test the quality of sea waters off the coast of Mostaganem, using the test of larval development of the purple sea urchin Paracentrotus lividus (Lamarck, 1816), species widely used for this type of analysis. In fact, the sensitive phase of embryonic and larval development of the sea urchin is used as a bioindicator of the health of the marine environment. Two sites situated in the Mostaganem coastline (Stidia and Kharouba) were selected. This choice is based on their exposure to different sources of pollution. The use of the echinoid P. lividus revealed a higher degree of disturbance at the site of Kharouba marked by a relatively low rate of normal larvae (71.2%) against the highest rate (84.1 %) obtained at Stidia station. The analysis was thorough two years later, by studying the ability of the sea urchins to normal and viable larvae (tests of fertilization and larval development), at the site of Kharouba. Also, the temporal comparison of the obtained results during the two years (2011-2013) confirmed that the site of Kharouba is in state of continuous disturbance; caused by the pressure originating from various anthropogenic activities.