Project 3

Sensitivity of lake types and their phytoplankton to environmental disturbance

Based in: Estonian University of Life Sciences, Estonia

A hydro-meteorological disturbance is a temporary change in environmental conditions that causes a pronounced change in an ecosystem. In lakes such disturbances can be caused by, for example, sudden changes in wind (both storms and longer calm periods), air temperature (affecting the ice regime and stratification) or precipitation (causing flushing effects, changing water levels, and driving nutrient loads from the catchment). The aims of this project are to: 1. establish an index or a set of indices for quantifying potential environmental disturbance based on day-to-day changes in meteorological and hydrological forcing and map the index levels retrospectively at a regional/European scale; 2. identify how sensitive lake metabolism and the equilibrium state of phytoplankton are to potential environmental disturbance depending on (a) lake type parameters and (b) lake status parameters; and 3. assess the influence of phytoplankton dominant taxa on lake metabolism. To accomplish this, the doctoral student will (a) develop a conceptual framework for selecting hydro-meteorological disturbance factors for lakes and create an algorithm for combining them into an index or set of indices; (b) estimate lake metabolism based on high frequency dissolved oxygen measurements and analyse the dominance structure of phytoplankton in a number of lakes of different types (c) run enclosure experiments measuring metabolism of phytoplankton communities dominated by different taxa, (d) apply statistical analysis and use modelling tools for identifying episodic events, testing relationships between disturbance levels and episodic events, and between phytoplankton community structure and metabolism.


This student will be primarily based in Estonian University of Life Science, supervised by Prof. Peeter Nõges and Dr Fabien Cremona, and co-supervised by and spend study time with Dr Biel Obrador, University of Barcelona, Spain. The PhD will receive a double award given by Estonian University of Life Sciences (EE) and University of Barcelona (ES).