Since the middle ages large forest areas in Europe have been converted into managed forests and agricultural land and fragmented by infrastructure and human settlements. Today one third of Europe’s land surface is covered by forests, in Austria it is almost 50 %. Forests play a major role in the current climate change debate, since they are directly affected by changing climatic conditions but also mitigate climate change effects. Without forests, the global CO2 concentration would be 30 % higher than it is today. European forests sequester every year about 700 Million tons of CO2 by storing carbon in pools with a long residence time, not only in aboveground compartments of trees but also in roots, dead wood, soil and wood products. Storage in such pools is, however, temporary and the carbon cycle is closed when carbon is released back into the atmosphere, irrespective whether forests are natural or managed.
Natural (left) and anthropogenic (right) forests carbon cycle. Carbon dioxide (CO2) is removed from the atmosphere by photosynthesis and fixed in biomass. After tree death or plant harvest, C and O2 are converted into CO2 through respiration of decomposers or burning of biomass.
The Department of Forest and Soil Sciences at the University of Natural Resources and Life Sciences works along the whole carbon cycle from carbon uptake via photosynthesis to carbon release to the atmosphere and the confounding processes and drivers. The Department of Forest and Soil Sciences is a central hub for conceptual understanding and managing of carbon processes and thus a “Center for Carbon Management”, nationally and worldwide.
The most important input of carbon into forest ecosystems is photosynthesis; green plants convert atmospheric CO2 into biomass. Depending on the allocation of carbon into carbohydrates, its life cycle and residence time is very diverse. More than one third of the forest carbon is found in the above and below-ground biomass. The forest floor contains about 10% of carbon in deadwood or litter pools with highly variable residence times. More than half of the carbon is located in the forest soils and may stay there for thousands of years. However, climatic conditions, edaphic factors and forest management practices change the tree species composition and carbon allocation. The current condition of the forests is the result of complex interactions among many drivers (e.g. mortality, disturbance regimes), thus a transdisciplinary conceptual approach is needed to better understand forest ecosystems and to provide decision support to society and stakeholders.
The Department of Forest and Soil Sciences, University of Natural Resources and Life Sciences, has a long tradition in forest management including carbon management. The six research institutes within the department are working on the following topics:
- The Institute of Forest Growth develops models for the stem form and allometry of forest trees, provides sampling-based approaches for the estimation of biomass and carbon stocks and for the prognoses of their development in future periods, and quantifies the effects of tree species mixture and stand structure on the productivity and carbon sequestration of forest landscapes.
- The Institute of Forest Engineering develops concepts to optimize tree harvest, to mitigate disturbances of forest stands and soil and to maintain site fertility for ensuring a sustainable resource supply for the wood processing industry in order to replace fossil-based products.
- The Institute Forest Entomology, Forest Pathology and Forest Protection focuses on monitoring and assessing biotic forest threats such as insect pests and pathogens and develops tools in order to mitigate the extent and severity of disturbances to minimize negative effects on forest carbon stock.
- The Institute of Silviculture develops and applies modelling concepts for carbon uptake and release by forest ecosystems considering effects of forest management and quantifying effect of climate change on provisioning of ecosystem services.
- The Institute of Soil Research works on quantifying carbon stocks and uptake by forest soil and on assessing the impacts of extreme climatic events such as drought or intensive rainfall on greenhouse gas emissions.
- The Institute of Forest Ecology explores the interactions of disturbances and the carbon cycle, the role of roots and mycorrhiza on carbon sequestration and formation of stable humus systems.