Effects of diurnal temperature fluctuations and episodic temperature extremes on marine nematodes: a multi-level approach
Although changes in average environmental conditions can have serious consequences, the main impacts of global climate change on populations and communities may well result from changes in short-term climate variability. Those may affect different levels of ecological organization: from the individual to the ecosystem, including changes in reproductive success, population dynamics, species interactions, community structure and functioning. This thesis work aims to investigate the response of marine nematodes to such temperature stress conditions with focus on different levels of organization (from individuals to populations/communities) and complexity (including single species/species interactions) . The main research questions are whether: i) short-term temperature fluctuations affect individual performance and ii) medium-term temperature fluctuations affect population dynamics of marine nematodes and their species interactions. Microcosm experiments on closely related marine nematode species are performed under different thermal regimes to examine their plasticity, population fitness, feeding behavior and species interactions. We expect that changes in amplitude of diurnal temperature fluctuations may be very important determinants of the effects of temperature change on species interactions, affecting also assemblage structure and ecosystem functioning. The accurate measurement of nematodes’ response to stress will thus allow us to make proper predictions of how species and communities respond to climate change effects.