FLS trials new technique to restore sand dune habitats
A new method of restoring sand dunes to their pristine and natural condition is being trialed by Forestry and Land Scotland at Morrich More, a site near Tain in East Sutherland.
The project aims to remove trees – planted decades ago in a misguided attempt to help prevent dune erosion – and create the conditions that will allow dune vegetation to once more take hold and allow natural processes to conserve the coastline.
Suzanne Dolby, FLS Environment forester (North Region), said:
“Sand dunes are vulnerable to coastal erosion, especially in the face of rising sea levels and more frequent severe weather events.
“Decades ago, the thinking was that planting trees on dunes would help to prevent them from being eroded and that this would help protect Scotland’s coastline. However, tidal and wave action continued to drive erosion under the tree roots and actually encouraged erosion.
“These days, the awareness and understanding of the cycles that sand dunes go through – and their value as habitats in their own right - is much more prevalent so we are looking at how best we can restore sand dunes to their natural state.”
Sand dunes help to protect the coastline and are likely to be an increasingly important defence against sea level rise as a result of the Climate Emergency.
Natural and healthy dune systems change their formation in response to wave, wind and tidal action, with some sand removed only to be replaced at a later stage with deposits of new sand. This self-sustaining process can play out in the course of one storm but more often occurs over many years and, if viewed at a particular moment in the cycle, could give the impression that the dunes are disappearing.
Tree planting in previous generations attempted to stop this apparent erosion and fix the dunes in place – but it also interrupted the natural process of replenishment, as well as the colonisation of dune vegetation.
“Previous restoration attempts over the last 15 years have failed to properly restore open dunes because they did not deal with a surface layer on the dunes that had been enriched by fallen leaves or needles, conditions which favour woodland plants and that effectively prevented more sensitive dune plants from surviving.
“The method we’re trialing now involves removing the trees and scrub and scraping and burying the plant litter layer to leave a bare sand surface, which will hopefully support the rare vegetation that is special to these dunes.”
The area will be closely monitored over the next 5 years to assess the effectiveness of the restoration process.
Notes to editors
Forestry and Land Scotland (FLS) manages forests and land owned by Scottish Ministers in a way that supports and enables economically sustainable forestry; conserves and enhances the environment; delivers benefits for people and nature; and supports Scottish Ministers in their stewardship of Scotland's national forests and land.