About us

We explore nature and the control of ecosystem processes in the forest landscape, including those of different forest types, wetlands, streams and lakes as well as the links between these systems. This fundamental understanding will enable us to design, monitor and evaluate the outcome of new ecosystem management approaches.

Exploring the influence of silvicultural systems and forest management operations on the output of ecosystem services is an essential part of our mission and our studies, therefore, encompass both managed and unmanaged systems.

We aim to deliver scientifically founded decision support and knowledge to the surrounding society. In addition to scientific communication; teaching undergraduate and graduate students and taking part in the public discourse are indispensable activities to maintain our role as knowledge providers.

Our work involves an extensive collaborative network both locally and internationally. This enables us to integrate studies of biospheric interactions as well as the interactions between the biosphere, the pedosphere, the hydrosphere and the atmosphere.

Forest ecophysiology includes nitrogen nutrition of plants in general and of forest plants in particular and its key role in boreal forest ecosystems.

Our research deals with the nitrogen nutrition of plants in general and of forest plants in particular. Nitrogen, being the mineral element needed in the largest amounts by plants is also, in most terrestrial ecosystems, limiting for plant growth. In Boreal forest ecosystems, this limitation is in spite of large stocks of organic nitrogen in the soil. Thus, the production of plant-available nitrogen sources is a key process in these forests.

But which are the plant-available nitrogen sources? What sources of nitrogen do plants actually use?

Using a broad array of techniques, we are trying to answer this question. With the help of dual (C-13, N-15) labelled amino acids we have quantified the uptake of intact amino acids in various plants directly in the field. Many researchers in various ecosystems now use this technique. We have characterized the mechanisms enabling plants to absorb amino acids. These findings enable us to produce plants with drastically altered capacities for amino acid uptake, plants that can be used to study the importance of amino acids as nitrogen sources in various soils. 

Our research deals also with carbon-nitrogen interactions in plants and the role of nitrogen for root: shoot allocation. It is well known that nitrogen availability is a strong determinant of root: shoot allocation of plants. But what roles do the different nitrogen compounds in the soil play in the allocation of carbon between above- and below-ground compartments and in shaping plant structures? These questions are targeted at new projects within the ecophysiology competence area. 

Because of the strong nitrogen limitation of forests in our part of the world, nitrogen fertilization usually results in substantial growth increases. The practice of adding nitrogen to forests has received increased attention recently, an interest driven by the strong demand for biomass from different sectors. Our research will provide the basic knowledge for understanding how trees react to increased nitrogen availability and help develop new fertilizers and new forests' nitrogen management practices.

Research group leaders

Torgny Näsholm

Professor in Tree Ecophysiology

In the Forest History research group, we focus on understanding how forest ecosystems have developed in Northern Scandinavia by exploring people and forests historically from a long-term perspective. 

Forest landscape biogeochemistry includes the hydrology and biogeochemistry of forested watersheds and the speciation, mobility and bioavailability of trace metals. Our major research objectives are to understand the biogeochemical transformation and cycling of energy, water, carbon, nitrogen and other elements in the boreal landscape. Much of our research is focused on the exchange processes between ecosystems and the atmosphere and hydrosphere respectively. A critical tool in our research is close access to a number of intensively instrumented research field sites. We work across spatial scales from the molecular level to the landscape level. 

Research group leaders

Hjalmar Laudon

Professor and Chair of forest landscape biogeochemistry

This subject area includes studies on the effects of natural disturbances, climate change and forest management on ecological processes underlying forest regeneration in boreal forests. The key factors of interest are the responses of understory vegetation (ericaceous dwarf shrubs and mosses) and soils controlling early seedling establishment and growth. We also study the interactive effects of management, wildfire and climate warming on the early development of conifer and broadleaved forest stands, and how these interactions impact the biotic and abiotic environment in the vicinity of the tree seedling.

Research group leaders Forest regeneration

Marie-Charlotte Hegethorn

Professor and Faculty chair in Forest Regeneration

Forest soils include plant-soil relations, geochemistry and pedology. 

This field encompasses several subdisciplines; in our case especially plant-soil relations, geochemistry and pedology. A major focal area is interactions among soils, microbes and plants, and their implications for forest nutrition management, long-term productivity and the carbon balance. 

Another major focal area is the biogeochemistry of mercury in soils, especially the effects of forest activities and restoration of wetlands. Our studies are based on detailed analysis in the laboratory, e.g. involving X-ray absorption spectroscopy to reveal the chemical speciation and linkage between mercury, sulfur and iron geochemistry, and very intensive pulse-chase isotope labelling experiments to study the cycles of nitrogen and carbon directly in the field. 

Research group leaders

Peter Högberg 

Professor of Forest Soil Science

Ulf Skyllberg

Professor

Our research aims to integrate these themes as much as possible, to provide an understanding of how forest community structure interacts with ecosystem processes.  We aim for our research to contribute to solving issues important to society, including preservation of biodiversity and ecosystem functioning, forest resilience in response to climate change, and sustainable use of forest resources.   

Research group leaders Forest vegetation ecology

Michael Gundale

Silviculture includes silvicultural systems and forest management operations, with focus on the boreal and tropical region.

The aim of silvicultural research is to evaluate the effects of forestry practices, like regeneration, pre-commercial thinning, thinning, fertilization, and felling, on the future development of forests. The research is based on long-term field experiments, survey-studies, laboratory experiments, and simulations. The department is responsible for the development of knowledge for forming silvicultural practices and systems, which enable a sustainable use of the forest resource. The topic is central to the department's education, at both undergraduate and graduate level.