Claire et Katja représentent le Luxembourg

avec leur travail:
“Etude de l’influence du pH de l’eau sur la croissance de Chlorella vulgaris”

European Union Contest for Young Scientists Lisboa, 24 – 29 Sept. 2010
Claire Schelinsky and Katja Michalski

Anthropogenic carbon dioxide emissions have increased steadily since the Industrial Revolution, causing not only high levels of atmospheric green house gas but also a significant change in the chemistry of ocean and surface waters. Scientific research is focused on its effects on the biodiversity of seawater as well as freshwater organisms. Compared to the pre-industrial era, the pH of water has already decreased by 0.1 units, which seems to have an impact on the aquatic ecosystems. A further reduction of 0.3 to 0.4 units is expected until the end of this century. It is believed that numerous organisms won’t be able to adapt in time to the fast change of pH and hence will simply disappear, causing an unprecedented shift in microorganism populations. In the present report, the authors would like to present their study of the effect of freshwater pH on Chlorella vulgaris, a single-celled algae acting as a key organism in the foodchain of aquatic systems.