Abstract
The aim of this project is to be able to understand how climate change may affect the timing and duration of the clear water phase in eutrophic lakes and how this, in turn, affect the potential for macrophytes to get re-established each spring. Lakes with abundant macrophytes support a high diversity of both plants and animals, and have a good resistance against increasing nutrient loads and climate change; changes that may otherwise turn the lake into being turbid, having low biodiversity and being dominated by phytoplankton. How shallow north temperate coastal lakes will respond to global warming has been debated in recent years. I will concentrate on the key role of grazing zooplankton in initiating a clear water period in spring, a period during which vegetation may expand. The objectives of my project are: 1) through a three-year field study determine the effect of timing on zoo- and phytoplankton spring dynamics in the edge zone between vegetation and open water, 2) experimentally determine the timing of events including both consumptive and behavioural interactions between young-of-the-year fish and zooplankton, 3) experimentally determine how cascading behavioural and consumptive interactions (involving piscivores, planktivores, zooplankton) affect the distribution of zooplankton close to the vegetation edge at different times during spring, 4) through modelling evaluate the ability to predict zooplankton spring dynamics using long-term abiotic and biotic data.
Sweden