Introducing the MARS river and lake experiments

NIVA experimental flumes for studying extreme flows in Nordic Rivers. Image: Susi Schneider

In previous posts, we have written about how freshwater ecosystems around the world are subject to multiple stresses on their health and diversity – for example, pollution, water abstraction and river fragmentation through dam building.

Researchers from the MARS project are interested in understanding the causes and impacts of these multiple stresses, and – crucially – how they make interact and multiply any potential negative impacts on the environment.  Similarly, there is a need for research to simulate how multiple stresses might affect freshwaters under future climate change – how will changes to rainfall, temperature and storm frequency (amongst other factors) affect multiple stresses on freshwater ecosystems?

In order to explore some of these questions, MARS researchers have set up seven experimental sites across Europe as part of Work Package 3, where the effects of multiple stresses under different possible climate scenarios will be simulated.  Three lake experiments will take place in the UK, Denmark and Germany using mesocosms.  Four river experiments will take place in experimental flumes and channels in Portugal, Austria, Denmark and Norway.

Each experiment will focus on different aspects of how a freshwater ecosystem might respond to different stresses and changes to climate.  By carrying out the river experiments in artificial channels and flumes, the MARS researchers can control and monitor all the factors affecting the experimental ecosystems, and closely monitor the results.  Similarly, the mesocosms used in the lake experiment create closed conditions which closely simulate the natural environment, and again can be controlled and monitored.  The experiment methods will be harmonised across all sites, which means that the data produced will give excellent coverage of different European environments under a range of potential climate conditions.

Over the coming months, we’ll write about each experiment in more depth:

• Low Flows in Nordic Rivers
• Extreme Flows in Nordic Rivers
• Peak Flows in Alpine Rivers
• Water Scarcity in Mediterranean Rivers
• UK Lake Mesocosm Experiments