Effects of Implemented Restoration Measures

Fire has historically been a key natural disturbance in boreal forests, creating habitats vital for biodiversity. During the last 150 years, effective suppression and land-use change have drastically reduced fire frequency, leading to declines of fire-dependent species. To counteract these losses, prescribed burning has been widely applied in Sweden since the 1990s. Although effective, it is costly and cannot be used everywhere. This has recently spurred the development of complementary fire-mimicking methods at the tree level, aiming to create fire scars and resin-impregnated wood that develop into long-lived kelo pines – habitats of high conservation value.

The project will evaluate two such methods: stem-base burning, where small controlled fires are lit at the base of standing pines, and bark-stripping methods, including “katning,” girdling, and topping. Three central questions will be addressed: (1) Does landscape context influence colonisation by fire-dependent beetles on stem-base burned pines? (2) Does seasonal timing of burns affect resin flow and kelo formation? (3) Which bark-stripping methods are most efficient in producing resin-rich wood?

The work is organised in three packages. A large-scale field study (25–30 sites across Sweden) will assess beetle colonisation on stem-base burned pines in relation to local and landscape conditions. A replicated experiment will compare early summer and winter burns, with detailed analysis of resin chemistry and distribution. Finally, a unique long-term bark-stripping experiment (est. 2020) will be evaluated for efficiency in producing resin rich wood.

By combining ecological experiments with collaboration with authorities and forest companies, the project will deliver robust and practically relevant guidelines. The results will help the Swedish EPA, county boards, and companies apply “the right measure in the right place,” supporting fire-dependent biodiversity and habitats in boreal pine forests.

Project Manager: Mattias Edman, Mid Sweden University 

Funding: 3,594,315 SEK

Wetland restoration and rewetting of previously drained land are important parts of environmental policies in many countries, including Sweden. This is in line with solid scientific evidence on the multiple ecosystem services of wetlands, including flood protection, drought mitigation, carbon sequestration, nutrient retention and biodiversity support. However, a key challenge that this project addresses is that the ecosystem services of restored wetlands can vary considerably across the landscape. Wetland restoration success therefore depends on where measures are taken and how they are designed and managed, particularly regarding the outlet conditions that govern post-restoration water levels. RemWat will use the unique data potential of Sweden’s unprecedented rewetting efforts to address the challenge. This e.g. regards data from 16 sites where we are active through parallel projects, with multi-year, highfrequency water level data from 70 wells in the wetlands and the adjacent groundwaters. Considering also complementing hydrogeological, vegetation and water quality data, we will synthesize and produce scientific evidence on how hydrological water level management can be used in wetland planning to control restoration results. Through (i) statistical, numerical, and AI-based analyses, together with (ii) a series of knowledge cogeneration (KC G) seminars with actors from multiple societal sectors and different administrative levels, we also expect to develop simplified predictors for restoration outcomes. These can be used to assess which wetland restoration goals are likely to be achievable at which sites. Predictive tools including Hype that supports user services of SMHI and SGU will also be adopted to assess long-term wetland functioning in future climates. Besides scientific publishing, the project results will be presented in the form of policy briefs and reports containing recommendations for rewetting work, as well as at stakeholder meetings.

Project Manager: Jerker Jarsjö, Stockholm University

Funding: 3,999,406 SEK

The project will study how wetland restoration in agricultural landscapes can be optimized in relation to the goals of reducing climate impact and promoting biodiversity. The need for rewetting is motivated by two EU directives (LULUC F and the Nature Restoration Law). In Sweden, priority is given to rewetting previously drained peatlands on agricultural land, which release significant amounts of C O₂ from decomposed material. Wetlands are also restored to benefit biodiversity, but environmental factors that favor biodiversity risk leading to higher methane emissions, which complicates efforts to meet climate goals.

The project will quantify effects on greenhouse gas emissions and biodiversity during rewetting projects using a BAC I (before–after control–impact) design, by following rewetting projects planned for 2026. The measures are distributed across three regions (Östergötland, Skåne & Västra Götaland), enabling evaluation of both local and regional variation. In each region, five sites will be rewetted along with an equal number of control sites. At some sites, greenhouse gases will be quantified with specially designed drones that measure carbon dioxide, methane and nitrous oxide. Effects on biodiversity will be studied using traps and direct observations. The biodiversity focus is on arthropods, but bird and bat activity will also be studied. To understand underlying mechanisms, hydrological dynamics (water levels and extent of flooding), soil chemistry, and other management factors (e.g., presence of grazing animals) will be quantified.

Through these studies, we aim to develop evidence-based guidelines for balancing reduced greenhouse gas emissions with conservation of biodiversity. By studying complex relationships between emissions, biodiversity and e.g. soil type, water levels, and grazing animals, the project’s ambition is to increase knowledge about the management and restoration of wetlands to meet both climate and biodiversity conservation goals.

Project Manager: Peter Hambäck, Stockholm University

Funding: 4,000,000 SEK

There is an urgent need for restoration in Sweden’s coastal and marine areas, where currently no habitat type has favorable conservation status. The restoration challenge is complex, as many areas are affected by widescale pressures acting in concert with local impacts. Although some restoration measures are underway, a national strategy for optimising marine restoration efforts is lacking. C urrent efforts are often fragmented, spatially limited and time-consuming, which may cause costly delays in reaching restoration objectives. The purpose of the Restore-C project is to support effective strategic planning for coastal marine restoration. Our aim is to develop key performance indicators (KPIs) to assess and evaluate the effectiveness of coastal restoration measures in relation to ecological, social and economic sustainability aspects. We will develop the indicators based on scientific studies, stakeholder dialogues and analyses of spatial data, and apply the KPIs to identify coastal areas with potential for high underwater nature values where restoration measures can provide the greatest ecological, social and economic benefits. One key deliverable is an online toolbox enabling stakeholders to make informed decisions about which restoration methods are relevant and effective for their particular site and situation. Maps of nature values will contribute essential knowledge for sustainable marine coastal planning, and hotspot maps will highlight where restoration measures would have the greatest cost-effectiveness relevant to the ecological goals. The results will inform restoration measures at local and national scales, contributing to Sweden’s obligations under the Nature Restoration Regulation. Scientifically, Restore-C will advance our understanding of how spatially explicit measures and spatial optimisation can influence restoration effectiveness and about processes for including knowledge from multiple sources in management actions.

Project Manager: Carolyn Faithfull, Swedish University of Agricultural Sciences

Funding: 3,999,834 SEK

This project will evaluate the responses of riparian vegetation and aquatic and riparian insect communities to ecological restoration of (1) river reaches affected by timber floating, and (2) dam removal. Ecological restoration of rivers and streams is increasingly common, but whether restoration succeeds in enhancing biodiversity and reinstating ecosystem services is poorly known. Our project will answer whether recovery occurs, which aspects of the ecosystems that recover and at what spatial scale, and how long it takes. This will enable giving recommendations on how to best perform restoration, which sites to prioritize, and how to best evaluate restoration success. We ask how the area, abundance and species richness of riparian vegetation, and the abundance and species richness of aquatic and riparian insect communities have responded to restoration. We also address how recovery varies depending on spatial scale, and which metrics are best to use to evaluate restoration success. This is done by surveying river reaches representing different times since restoration (up to more than 30 years ago). For the dam removal study each dam removal reach is compared with a control reach, which is complemented by before/after studies, and in the timber floating study, we also survey pristine and unrestored control reaches. The EU Water Framework Directive and the EU Nature Restoration Law make decisions on dam removals and timber floating restoration increasingly common, making it important for county boards, water authorities, the Swedish Agency for Marine and Water Management, the Swedish Environmental Protection Agency, and representatives of the Land and Environment Court to have knowledge of to which degree target ecosystems recover and at what speed. This will enable them to provide recommendations on the best locations for restoration, how to design the restoration actions, and how the actions are to be followed up to assess success. 

Project Manager: Roland Jansson, Umeå University

Funding: 4,000,000 SEK

Centuries of human modification have simplified Swedish rivers, disrupting the water and sediment processes that sustain ecosystems. Large-scale restoration is underway, but efforts have largely targeted channel form and physical complexity, with limited evaluation of whether hydromorphic processes are restored. Consequently, despite high costs, outcomes for biodiversity, resilience and Swedens goal for thriving rivers, remain uncertain.

This project will quantify how restoration affects hydrological and geomorphological processes and their links to habitat and resilience. We will address three questions: (1) how restoration alters water and sediment storage, transport, and spatial variability; (2) how outcomes vary with landscape setting (paraglacial vs. alluvial) and restoration technique (channel reconfiguration, low-tech additions, process reset); and (3) how restored processes influence habitat diversity and resilience to floods. We will monitor 18 study reaches, combining continuous measurements of hydromorphic processes with assessments of habitat and flood resilience using insitu monitoring, remote sensing and sediment modelling.

The project is co-designed with restoration practitioners (C ounty Administration Board Västerbotten, Rewilding Sweden, Sportfiskarna) to ensure direct application. Outputs will include: (i) a report guiding process-based restoration in Sweden, and (ii) a low-cost monitoring protocol enabling practitioners to implement coordinated, comparable evaluations. Scientifically, the project will advance understanding of how restored processes support river resilience - knowledge that is increasingly critical under climate change..

Project Manager: Richard Mason, Umeå University 

Funding: 3,984,832 SEK