Résumé
Biological diversity (first used by J. A. Harris, 1916), or biodiversity for short, is the variety of life and its processes and it includes the variety of living organisms, the genetic differences among them and the communities and ecosystems in which they occur. Studying and understanding the effects of human and non-human actors on biodiversity remains crucial since they could imply significant effects on essential ecosystem services to humans. For example, environmental change (a disturbance of the environment, often resulting from human activities, natural phenomena and ecological processes) can result in modification of species traits that can result in the entire loss of that species.In this PhD research, we developed analytical tools to study the effect of temperature (an aspect of environmental change) on the sustenance of two closely related cyanobacteria strains that are important for oxygen production. We achieved this using data from laboratory experiments designed under three different temperature conditions. Only at the highest temperature level $(22^\circ C)$ did increasing cell size (trait) over time reduces the growth of these cyanobacteria. The consequences of this effect were important, as it implies the loss of coexistence, that is one of the cyanobacteria dies off. We conclude that effects of temperature on cyanobacteria traits are likely to predict effects on growth with far-reaching implications. It remains crucial to perform further experiments using other cyanobacteria strains and species to confirm these results, and also to potentially identify strains or species whose traits are robust to temperature change.
| la date de réponse | 31 janv. 2023 |
|---|---|
| langue originale | Anglais |
| L'institution diplômante |
|
| Superviseur | Frederik De Laender (Promoteur), Marc Aerts (Copromoteur), Patrick Kestemont (Président), Thomas Neyens (Jury), Christel Faes (Jury), Annick Wilmotte (Jury), O. Thas (Jury) & Simone Fontana (Jury) |