Significance of intraspecific variation for decomposition processes

Over the last decades, communities and ecosystems globally have undergone dramatic changes, accompanied by rapid declines and changes in biodiversity at all levels, from biotopes to species and genetic variation within species. Consequently, considerable effort has been invested in ecological research to understand the functional importance of biodiversity as a regulator of ecosystem processes, dynamics and functioning. However, intraspecific (phenotypic) variation has been considered rarely in this context. With the proposed project, we aim at studying how intraspecific variation in ecological and physiological traits affect ecosystem processes and, respectively, is affected by environmental extremes. We will study decomposition as a fundamental ecosystem process, being controlled by macro-detritivores, such as terrestrial isopods. We hypothesize that (I) populations with variable digestive phenotypes are more efficient in consuming and breaking down diverse litter mixtures, and the relevance of intraspecific variation increases with increasing litter diversity; (II) variable populations are more resistant and tolerant against environmental fluctuations and extremes; (III) extreme (weather) events select for phenotypes that are able to cope with such extreme conditions, and populations from naturally fluctuating environments exhibit higher variation, as well as higher resistance and tolerance against environmental extremes. To test these, we will (I) experimentally increase intraspecific variation of detritivores and study its significance for decomposition processes; (II) experimentally breed different levels of intraspecific variation within populations, expose them to different environmental conditions and study their contributions to decomposition processes; (III) expose populations from different habitats that differ in the extent of environmental fluctuations to extreme events.

No additional funding sources recorded.