From past to future – Discover the opportunities within the experimental forests

“100 years of field-based forest research” has been our slogan since 2021, but our roots run even deeper. Our portfolio contains field trials that are over 120 years old. The Unit for Field-based Forest Research was established in 2003 and tasked with managing and developing the Faculty of Forest Sciences' experimental forests and long-term field trials. Many of the older trials focused on forest production, but our focus is moving away from research on forests to research in forests.

The unit’s eight experimental forests were established between 1921 and 1988, and are evenly distributed across the country. Four of them have permanent staff who manage the faculty’s over 1,800 field trials, and provide assistance to researchers in the form of planning, establishment, and data collection from new projects.

Climate and the environment have long been important topics at the experimental forests, and the unit has positioned itself as one of the nation’s great resources in climate research. Our climate reference program was standardised across all experimental forests in 1980, with the goal of delivering high-quality climate data from our meteorological stations. The Unit is also the base for SLU’s stewardship of the Swedish phenology network, which collects phenological data from both professionals and the Swedish public. In 2012, we joined the Swedish Research Council (VR) initiative ICOS (Integrated Carbon Observation System), which among other things led to the installation of a 150-meter-tall mast in the Svartberget experimental forest. This has been our path to becoming an important node for global climate research.

Hydrological measurements have also played a big part at several experimental forests. Run-off and water chemistry have been measured under different management regimes at the Svartberget catchment since the 1970s. This has become the foundation of the Krycklan Catchment Study, a globally well known infrastructure. Krycklan attracts researchers from across the world, and produces around 50,000 chemical measurements per year, in addition to continuous measurements of temperature, run-off and water level in several streams.

In 2013, the Unit became part of yet another VR initiative: SITES (Swedish Infrastructure for Ecosystem Science). We entered with our entire portfolio of field trials, and expanded our activities with more hydrological measurements in Asa and in lakes. SITES has brought with it infrastructure for multispectral measurements with drones, aircraft, and static installations, as well as the installation of floating mesocosms at the Asa and Svartberget experimental forests for controlled experiments in aquatic environments.

Still, it doesn’t end there. The Unit also participates in other infrastructure initiatives, among others: eLTER Sweden, which is a network of Swedish fielstations who do environmental research and monitoring, the EU initiative INTERACT (International Network for Terrestrial Research and Monitoring in the Arctic), and most recently ACTRIS (Aerosols, Clouds and Trace Gases Research Infrastructure) which is co-located with ICOS and intends to measure aerosols and short-lived pollutants in the atmosphere. There is also talk of us becoming a Living Lab.

Taken together, this means that our experimental forests can not only provide exceptionally good background data, but also that our technical staff and engineers can aid with planning and management within a broad variety of subjects.

An English-speaking colleague of mine once commented on our English name, and told me that putting ’The’ in front of ’Unit’ implies that we are the one and only Unit for Field-based Forest Research (and that the name was pretty long-winded). At that occasion, I jokingly told her that we really were ’The’ Unit for Field-based Forest Research, a clear global leader. Perhaps there is some truth to that.

Kim Lindgren, writing for the leadership team