Abstract
The aim of my project is to evaluate the effect of among-year climate variation on the recruitment of planktonic herbivores in lakes and the resulting effects on annual water clearing events during late spring known as "clear water phases" (CWP). The rapid growth of crustacean herbivores and the resulting depression of their algal food is considered the main mechanism leading to a CWP. Using a structured population model and laboratory experiments together with field sampling data and evaluation of historical data from two large North American lakes, I will test the hypothesis that climate during late winter and early spring influences the timing, magnitude and duration of CWP:s through its effects on the recruitment of planktonic herbivores from diapausing eggs. My studies will be a part of a larger three year project at the host department aimed at establishing and relating conflicting theories on factors influencing occurrence, timing, duration, and magnitude of CWP:s. The development and evaluation of theoretical models describing and predicting herbivore-plant interactions with effects at the ecosystem scale will benefit fundamental science. Knowledge of the ecological mechanisms through which climate conditions during winter may affect water clarity and quality during late spring and summer in lakes gained in the project will be of great importance for water quality management in the face of climate change.
Sweden