Hulda Birna Albertsdóttir will defend her master's thesis in Natural and Environmental Sciences, Reclamation of snow avalanche protections: Planning, implementation and restoration success at the Faculty of Nature and Forest Sciences at the Agricultural University of Iceland.
Hulda Birna's supervisor is Dr Ása L. Aradóttir, Professor at the Agricultural University of Iceland, and her co-advisor is Magnea Magnúsdóttir, Environmental and Restoration Manager at ON Power.
The examiner is Dr Hafdís Hanna Ægisdóttir, Director of the Sustainability Institute at the University of Iceland
The master's defence will take place on Tuesday, May 28, 2024, at 3:00 PM in Sauðafell, on the 3rd floor in Keldnaholt, Reykjavík, and on Teams. The defence is open to everyone.
Abstract
Avalanche guards, i.e. large structures built in order to reduce the risk of avalanches reaching populated areas, are essential to protect urban areas under threat of such natural disasters. These guards are often enormous earthen structures that can cause severe damage to natural ecosystems, often reducing the biological diversity essential for ecosystem function and services. The goal of this project was to assess the process of revegetation of avalanche guard construction sites in the Westfjords, i.e. preparation, implementation, results, and follow-up, with the main aim of identifying factors that could negatively influence the revegetation process. Of the eight avalanche guard projects assessed, two projects or sites were evaluated for their impact on ecosystems and restoration of native vegetation eight years post-construction, i.e., guards in Bolungarvík and below Kubbi in Ísafjörður. Each site was divided into three parts where vegetation assessments were carried out. This includes areas in the front of the guard structures, on the mountain behind the guards and undisturbed reference areas. Results were put into the context of international standards for ecological restoration, particularly focusing on the principles and standards published by the Society for Ecological Restoration (SER).
The assessed avalanche guard projects in the Westfjords varied in size and were in all cases, sown with grasses, sometimes mixed with white clover or birch seed. In most cases, additional goals included restoring native vegetation, however, this was not stated as main goal of the reclamation. The original goals of the revegetation process were in many ways clear and ambitious. However, the results revealed issues at most stages, including: 1) reclamation targets were poorly introduced or not included in implementation phase; 2) the reclamation aims and objectives were not strictly followed; and 3) monitoring and evaluation was not used as a bases for corrective actions. Originals plans to follow-up, intervene and monitor, in order to achieve the goals set in the revegetation plans, were not followed, and it seems that nothing was done to stop the spread of invasive species. The involvement of stakeholders seems to have been lacking in all project processes as well.
The species composition on the avalanche guard structures (guard, behind guard) at the Ísafjörður and in Bolungarvík site eight years after revegetation varied greatly and was generally very different from the reference areas. Species richness of vascular plants was the highest in the reference areas and lowest on the guards. Of the species groups, the cover of grasses, especially the seeded grass species, was high, while the cover of native grasses was very low. Mosses had started to colonize the construction areas but, neither shrubs, trees nor bushes were found in any location, except those who were planted in Ísafjörður. The coverage of forbs was relatively high, with lupin being very widespread, especially in the Bolungarvík site. Other species groups had very low cover. These results therefore indicate limited restoration of natural vegetation in the construction areas and a high abundance of seeded grasses. This poor recovery may be attributed to the relatively short time since sowing (eight years), the choice of revegetation methods, as well as a lack of intervention to prevent the spread of invasive species.
The result of this study show that revegetation in the construction areas in Bolungarvík and Ísafjörður had not contributed to the recovery of biological diversity, as Icelandic laws of natural conservation stipulate (law no. 60/2013). It is highly likely that monitoring and evaluation could have yielded better result in terms of revegetation and, may have been instrumental in preventing the spread of invasive species. Setting clear goals regarding the restoration of natural vegetation and other revegetation and monitoring is essential and should take place during the planning and the goals, are kept strongly in mind and revisited often during the preparation, implementation and monitoring process.
