Spring Semester 2022

A year of leaf litter dynamics in headwater catchments.
Eva Cereghetti

Leaf litter in a tributary of Lake Constance © Eva Cereghetti

Leaf fall is often a symbol of seasonal change, a sign that the growing season has come to an end and winter is just around the corner. For small streams, leaf fall represents a fundamental input: nutrients. Especially within forests, where algal growth in streams is limited due to the lack of direct sunlight, streams and their communities rely heavily on leaf litter to provide carbon, nitrogen, phosphorous and other nutrients necessary for growth and survival. Within the Altermatt Lab, Eva Cereghetti is researching the dynamics of leaf litter in freshwater streams. She is investigating how this dead organic material enters the aquatic system and is (re)cycled through the shredding activity of amphipods, small crustaceans with a central role in freshwater habitats. The focus of the research aims to expand the temporal scale at which these processes are investigated. Rather than concentrating on the autumn season (i.e. the peak input period), empirical data to describe leaf litter dynamics is being collected throughout a full year, to ultimately shed light on the importance of this material and energetic flow across the different seasons.