Peatland Lakes

The lowland peat landscape of Northern Europe is dotted with lakes, ranging from small ponds to vast expanses of water. These lakes are often dug out of the peat, and are hydrologically linked to the surrounding peatlands. Therefore their preservation and maintenance is co-dependent with supporting the fens and bogs in their catchments.

In the North Sea Region many of the shallow lakes are Eutrophic and turbid - meaning that their water is cloudy. Within living memory these waters were clear, and it was normal to be able to see to the bottom of these lakes, which were full of plant and fish life. Today many of them are a dull brown colour, with limited plant life. Some studies have suggested that an increase in temperature for Eutrophic lakes results in a greater release of carbon, therefore our lakes are at risk of releasing substantial amounts of carbon into the atmosphere as the planet warms. Improving the water quality is therefore an important action in protecting our long term environment, and preventing our region from causing further damage to the climate.

Eutrophic lakes are also more susceptible to blue-green algae blooms, posing dangers to animal and human health, and restricting recreation activities in those areas. 

Blue Green algae leeching into a river

Blue Green Algae spilling into a river in the Broads National Park - Photo Copyright Mike Page


There are 4 lakes within the CANAPE project - Hickling Broad (UK), Zuidlaardermeer (NL), De Leijan (NL), Holter Meer (DE). Each of these lakes, to varying degrees, suffers from turbidity and has a poor level of biodiversity. The project will support a range of interventions and investigations to raise water quality level. For more information on the lakes, see the "Our Sites" page. 


PCLake provides a model of the relationships between different environmental factors that lead to a lake being either turbid or clear. Using the model allows environmental management organisations to better design their interventions. The shallow lakes (often less than 1m in depth even when they are several kilometres wide) are referred to as "stable state shallow lakes," meaning that they will either be clear or turbid, and will remain in one state unless they "flip" into the other state. Moving to clear water means an increase in macrophytes (submerged plants), and a greater diversity of fish and invertebrate species. 

Within CANAPE we are aiming to develop knowledge of this methodology around the North Sea Region, and use the method to improve the management of lakes managed by the partner organisations, including in the Broads National Park in the UK, at Zuidlaardermeer in the Netherlands, and Holter Meer in Germany. 

Fish Tracking 

Understanding the behaviour of fish within the lakes, and the surrounding network of rivers is a vital part of recognising the impact of water quality on local wildlife. CANAPE partner VHL is engaging in an innovative study to compare the movement of fish within a water system around Lake de Leijan, and spatial water quality analysis gathered throughout the lake. A large number of fish will be tracked in cooperation with local fishermen, and via a network of receivers positioned around the lake. 

Buoys holding receivers on lake surface

Part of the tracking apparatus at Lake de Leijan

For information on how to get involved with fish tracking, visit our citizen science page. 

Further Reading 

Davidson et al, Synergy between nutrients and warming enhances methane ebullition from experimental lakes - Nature Climate Change, January 2018.