Water quality and the legacy of historical ditching: Is wetland restoration amd ditch-cleaning a sustainable way forward?

Peatland drainage the last century has created about 1 million km of artificial streams, making it one of the most widespread human-induced environmental disturbances in Sweden. This large scale modification has largely unknown, but potentially enormous legacy effects on water quality.

Further, it is currently unclear whether restoration of drained peatlands, ditch-cleaning to maintain forest growth, or leaving legacy ditches alone for free development is the best strategy for avoiding negative water quality aspects in the future.

To close the gap between science and management, we will use a unique collection of field observations and modelling to address the question of whether i) restoration, ii) ditch-cleaning or iii) free development is the most effective way to avoid further water quality degeneration.

To do this, we will take full advantage of one of the most advanced field research infrastructures, the Krycklan Catchment Study (www.slu.se/Krycklan) in combination with fully replicated and controlled experimental catchments.

We will measure both natural and anthropogenic metals and trace elements, as well as nutrients, and suspended sediments to evaluate both the short and long-term effects on water quality in a way that has never previously been done.

Through these efforts, we will advance knowledge about different management options for historical peatland drainage, in to better our position to communicate science-based recommendations to land managers.