Climate change is expected to increase the future occurrence of extreme events, such as severe rainstorms and droughts, with potentially devastating effects on ecosystems, yet to date most research effort has centered on the impacts of gradually shifting ‘average’ conditions, not extremes. In freshwaters, shifts in precipitation patterns will modify water supply to freshwaters, altering hydrology. Extreme events are difficult to study in natural waters because they are, by definition, rare and unpredictable. Experiments have been advocated recently as useful alternative to surveys that are often confounded by long-term change in environmental conditions, and will be used here discern causal relationships among the many underlying stressors associated with extreme events. 

Mesocosm facility at UoB


This project offers the flexibility to combine research from archived data with new experiments conducted by the student in our new mesocosm facility to determine the effect of weather extremes on community structure and functioning (studying algae, invertebrates and fish) and food web

structure in replicate freshwater mesocosms located in the new Environmental Change Outdoor Laboratory (ECO-LAB) on the University of Birmingham campus. This project also benefits from being closely linked with a NERC grant investigating drought impacts on stream ecosystems. The successful candidate will also benefit from being part of a large, interdisciplinary, research team based at the University of Birmingham.

Training and Skills

CENTA students are required to complete 45 days training throughout their PhD including a 10 day placement. In the first year, students will be trained as a single cohort on environmental science, research methods and core skills. Throughout the PhD, training will progress from core skills sets to master classes specific to the student's projects and themes.  The student will acquire skills in the application of applying experiments to address key ecological questions


Year 1 establishment of experimental mesocosms and communities; refining methodologies and design of experiments; implementation of experiments.

Year 2: Further experimentation; sampling and data processing.

Year 3: Data analysis, reporting and write-up.

Partners and collaboration (including CASE)

The project will benefit from links with a NERC project testing drought impacts on food webs, and from a £700k investment in experimental facilities at UoB.

Further Details

Dr Mark Ledger http://www.birmingham.ac.uk/schools/gees/people/profile.aspx?ReferenceId=10622

Prof Alexander Milner