Standing water and sparse Scots pines. Photo.
RESEARCH PROJECT

Long-term evaluation of wetland restoration - effects on hydrology, biodiversity, water quality, and green-house gas balance

KEY POINTS
  • How does rewetting affect hydrology, water quality, biodiversity, and greenhouse gas balance over time?
  • • How can we increase the knowledge of rewetting effects through improved monitoring?
Updated: December 2025

Global goals

  • 3. Good health and well-being
  • 6. Clean water and sanitation
  • 13. Climate action
  • 14. Life below water

Short summary

This project reviews the current state of knowledge on effects of rewetting of drained wetlands including how quickly undesired side effects diminish. It also evaluates current practices for monitoring rewetting effects and provides recommendations for improving this monitoring.

Background

Extensive drainage of wetlands by ditching in Sweden has increased the amount of productive forest land but also negatively affected wetland function and ecosystem services such as water holding capacity, biodiversity and carbon retention. As a result, rewetting drained wetlands is encouraged from a political level to restore these ecosystem services. However, the question is whether it is possible to fully recover the many ecosystem services that natural wetlands contribute to, how long such recovery may take, and whether rewetting may lead to unintended side effects. 

Aim

The aim of this project is to compile the state of knowledge regarding how effects of rewetting on hydrology, water quality, biodiversity, and greenhouse gas balance develop over time. The study aim to answer the questions: (1) how long it takes before the desired effects of rewetting are achieved, and (2) how long any potential negative or positive side effects persist after rewetting. We will also evaluate how rewetting efforts are currently monitored and provide recommendations for improving effect monitoring, including suitable methods as well as appropriate measurement frequency and duration.

Results

In the report Långsiktig uppföljning av återvätning av dränerade våtmarker (in Swedish with English summary) you can read about the key findings from this project

Participants

  • Karin Eklöf, SLU (project leader) 
  • Pia Geranmayeh, SLU
  • Peter A. Hambäck, Stockholm University
  • Kevin Bishop, SLU
  • Irena Creed, University of Toronto
  • Frauke Ecke, University of Helsinki / SLU
  • Lei Gao, SLU
  • Thomas Grabs, Uppsala University
  • Gustaf Granath, Uppsala University 
  • Jerker Jarsjö, Stockholm University
  • Järvi Järveoja, SLU
  • Simon Kärvemo, SLU
  • Hjalmar Laudon, SLU 
  • Antonia Liess, Halmstad University
  • Amelie Lindgren, University of Gothenburg
  • Josefin Nilsson, Halmstad University
  • Mats Öquist, SLU
  • Tomas Pärt, SLU 
  • Pierre Tichit, SLU 
  • Marcus Wallin, SLU 
  • David Åhlén, Stockholms University

In our research catalogue, you will find more projects