1) Not biotic.
2) Non-living, e.g.: abiotic damage = damage caused by non-living agents (snow, storms, etc.) (MCPFE, 2003).
Forest damages caused by severe weather events like storm, wind, drought, snow but also avalanches, mudflows resulting in a loss of timber yield, land-scape quality, forest ecosystems and wildlife habitat. (Forest fire is a separate category)
The biomass of all living plant species from the ground and everything above it; includes stems, branches, foliage, bark, fruits and seeds and understorey vegetation (IUFRO, n.d.).
or
The mass, expressed as oven-dry weight (‘dry-matter’) of the woody parts (stem, bark, branches and twigs) of all living trees excluding stump and roots (based on ESA, 2024a).
In natural systems, the process of adjustment to actual climate and its effects; human intervention may facilitate adjustment to expected climate and its effects (IPCC, 2022).
AFM practices in OptFor-EU comprise modifications of existing management practices, management previously not used in the target region, but used in another region or completely new management practices. Development and implementation of AFM aim to address shortcomings of other management practices and/or anticipate expected adverse consequences due to current management and climate change.
Establishment of forest through planting and/or deliberate seeding on land that, until then, was under a different land use, implies a transformation of land use form non-forest to forest (FRA, 2025).
Any interval into which the age range of trees, forests, stands, or forest types is divided for classification, e.g. 1, 5, 10 or 20 years old age classes, as used in inventory or management (IUFRO, n.d.)
The area and/or proportionate representation of different age classes in a forest (MCPFE, 2003)
The gaseous envelope surrounding the Earth, divided into five layers: the troposphere, which contains half of the Earth’s atmosphere, the stratosphere, the mesosphere, the thermosphere and the exosphere, which is the outer limit of the atmosphere. The dry atmosphere consists almost entirely of nitrogen (78.1% volume mixing ratio) and oxygen (20.9% volume mixing ratio), together with a number of trace gases such as argon (0.93% volume mixing ratio), helium and radiatively active greenhouse gases (GHGs) such as carbon dioxide (CO2) (0.04% volume mixing ratio) methane (CH4), nitrous oxide (N2O) and ozone (O3). In addition, the atmosphere contains the GHG water vapour (H2O), whose concentrations are highly variable (0–5% volume mixing ratio) as the sources (evapotranspiration) and sinks (precipitation) of water vapour show large spatio-temporal variations, and atmospheric temperature exerts a strong constraint on the amount of water vapour an air parcel can hold. The atmosphere also contains clouds and aerosols (IPCC, 2022).
All living biomass of live roots beneath the ground surface. Fine roots of less than two mm diameter are often excluded because these often cannot be distinguished empirically from soil organic matter or litter (Carbon finance lexicon, n.d.).
The variability among living organisms from all sources including, inter alia, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part; this includes diversity within species, between species and of ecosystems (CBD, 1992).
Biomass is the total mass of living organisms in a given area or volume; dead plant material can be included as biomass (Carbon finance lexicon, n.d.).
The part of the Earth system comprising all ecosystems and living organisms, in the atmosphere, on land (terrestrial biosphere) or in the oceans (marine biosphere), including derived dead organic matter, such as litter, soil organic matter and oceanic detritus (IPCC, 2022).
Living; sustaining or having sustained life, often describing the biological components of an ecosystem (IUFRO, n.d.)Living; sustaining or having sustained life, often describing the biological components of an ecosystem (IUFRO, n.d.)
Forest damages caused by insects, diseases, wildlife and grazing resulting in a loss of timber yield, landscape quality, forest ecosystems and wildlife habitat.
BAU is the current typical forest management done in a particular OptFor-EU case study area. BAU implies that human interventions are done, such as removing or planting trees.
A naturally occurring gas, CO2 is also a by-product of burning fossil fuels (such as oil, gas and coal), of burning biomass, of land-use changes (LUC) and of industrial processes (e.g., cement production). It is the principal anthropogenic greenhouse gas (GHG) that affects the Earth’s radiative balance. It is the reference gas against which other GHGs are measured and therefore has a global warming potential (GWP) of 1 (IPCC, 2022).
A Carbon Pool is a reservoir of carbon. A system that has the capacity to accumulate or release carbon. Carbon pools are measured in terms of mass (e.g., metric tons of carbon). The seven major carbon pools associated with agriculture, forestry, and land-use projects are: above-ground non-tree biomass, above-ground tree biomass, below-ground biomass, litter, soil carbon, wood products, and dead wood (Carbon finance lexicon, n.d.).
The uptake (withdrawal from the atmosphere) and storage of carbon from the atmosphere in a carbon pool. Trees and plants, for example, absorb carbon dioxide, release the oxygen and store the carbon.
Retention of carbon in ways that prevent or delay its emission to the atmosphere as carbon dioxide. Silvicultural practices that encourage rapid, long term tree growth are an example. Crop residue retention practices designed to prevent erosion and improve the productivity of soil, such as conservation tillage, also retain larger amounts of carbon compared to many traditional cultivation practices.
Net removal of CO2 from the atmosphere into long-lived pools of carbon. The pools can be living, aboveground biomass (e.g. trees), products with a long, useful life created from biomass (e.g. lumber), living biomass in soils (e.g. roots and microorganisms), or recalcitrant organic and inorganic carbon in soils and deeper subsurface environments. (IUFRO, n.d.)
Carbon sink is any process, activity, or mechanism that results in the net removal of greenhouse gas from the atmosphere (Carbon finance lexicon, n.d.).
The quantity of carbon in a carbon pool (IPCC, 2022).
The eight OptFor-EU CSAs are located in Norway, Lithuania, UK, Germany, Austria, Romania, Spain and Italy, and cover the main forest ecosystem and all forest types of Europe. The CSAs were selected based on a list of criteria, including the application of a forest certification system and socio-economic analyses to improve the forest-based mitigation strategies and the existence of local studies about carbon sequestration, and provision of other FES and data availability. Within the OptFor-EU project we will validate the model outputs in the CSA for use in the OptFor-EU DSS.
A change in the state of the climate that can be identified (e.g., by using statistical tests) by changes in the mean and/or the variability of its properties and that persists for an extended period, typically decades or longer. Climate change may be due to natural internal processes or external forcings such as modulations of the solar cycles, volcanic eruptions and persistent anthropogenic changes in the composition of the atmosphere or in land use. Note that the United Nations Framework Convention on Climate Change (UNFCCC), in its Article 1, defines climate change as: ‘a change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods’. The UNFCCC thus makes a distinction between climate change attributable to human activities altering the atmospheric composition and climate variability attributable to natural causes (IPCC, 2022).
A plausible description of how the future may develop based on a coherent and internally consistent set of assumptions about key driving forces (e.g., rate of technological change, prices) and relationships. Note that scenarios are neither predictions nor forecasts, but are used to provide a view of the implications of developments and actions. (IPCC)
CSF is an emerging branch of sustainable forest management that aims to manage forests in response to climate change (Bowditch et al., 2020).
A collaborative process where an organization and external stakeholders – such as customers, employees, partners, and experts – work together to create new products, services, ideas, or solutions. Relates to user adoption and stakeholder engagement.
Non-living woody biomass either standing or lying on the ground. Excludes woody biomass contained in the litter, stumps or dead roots (FRA, 2025).
Human actions to reduce carbon dioxide emissions from human activities (IPCC, 2022)
computer-based tools which provide support to solve ill-structured decision problems by integrating database management systems with analytical and operational research models, graphic display, tabular reporting capabilities, and the expert knowledge of scientists, managers, and decision makers.
For the OptFor-EU DSS we will use a toolbox approach, where the different decision support tools will be designed to assist decision making in the various case studies.
Any of the intervals into which the range of stem diameters of trees or logs is divided for classification and use. Also the trees or logs falling into such an interval (IUFRO, n.d.).
The manner in which the trees in a stand are distributed over diameter classes (IUFRO, n.d.)
An exceptional period of water shortage for existing ecosystems and the human population (due to low rainfall, high temperature and/or wind (IPCC, 2022).
A complex of plant, animal and micro-organism communities and their non-living environment interacting as a functional unit (CBD, 1992).
Ecosystem health is a metaphor used to describe the condition of an ecosystem, by analogy with human health. Note that there is no universally accepted benchmark for a healthy ecosystem. Rather, the apparent health status of an ecosystem is judged on the ecosystem’s resilience to change, with details depending upon which metrics are employed in judging it and which societal aspirations are driving the assessment (IPCC, 2022).
Ecological processes or functions having monetary or non-monetary value to individuals or society at large. These are frequently classified as (1) supporting services such biodiversity maintenance, (2) provisioning services such as biomass, (3) regulating services such as climate regulation or carbon sequestration and (4) cultural services such as tourism or spiritual and aesthetic appreciation (IPCC, 2022).
The agricultural European Innovation Partnership (EIP-AGRI), which works to foster competitive and sustainable farming and forestry that ‘achieves more and better from less’.
An iterative process of actively soliciting the knowledge, experience, judgement and values of individuals selected to represent a broad range of direct interests in a particular issue, for the dual purposes of: creating a shared understanding; making relevant, transparent and effective decisions.
A novel set of indicators that will help characterise the potential for forest decarbonisation across all scales. They can be used to guide mitigation and adaptation measures, and to quantify the role of FMP for enhancing the capacity to mitigate climate change. The EFMIs can provide evidence on the impacts of FMP and associated NBS on FES, including decarbonisation potential. The concept is inspired by the World Meteorological Organisation’s Essential Climate Variables.
The New EU Forest Strategy for 2030 is one of the flagship initiatives of the European Green Deal and builds on the EU biodiversity strategy for 2030. The strategy will contribute to achieving the EU’s biodiversity objectives as well as greenhouse gas emission reduction target of at least 55% by 2030 and climate neutrality by 2050. It recognises the central and multifunctional role of forests, and the contribution of foresters and the entire forest-based value chain for achieving a sustainable and climate neutral economy by 2050 and preserving lively and prosperous rural areas.
The EFT is a nomenclature, enabling comparison throughout Europe of forests growing in similar ecological conditions and levels of anthropogenic modification, independent of national borders; it provides a harmonised classification for pan‑European‑level assessments of sustainable forest management (SFM), by offering ecologically meaningful units to reference and report national data on SFM indicators.
The European Forest Types are organised according to a hierarchical classification system structured into 14 first level classes (categories) and 78 second level classes (specific types). based on dominant tree species and ecological characteristics Europe (EEA website).
The EGD it is a package of policy initiatives, which aims to set the EU on the path to a green transition, with the ultimate goal of reaching climate neutrality by 2050. It supports the transformation of the EU into a fair and prosperous society with a modern and competitive economy.
The combined processes through which water is transferred to the atmosphere from open water and ice surfaces, bare soil and vegetation (as evaporation or transpiration) that make up the Earth’s surface (based on IPCC, 2022).
A stand, in which no or relatively small age differences exist among individual trees within it (usually less than 20% of rotation length), and defining average stand age is meaningful (IUFRO, n.d.).
Expansion of forest on land that, until then, was under a different land use, implies a transformation of land use from non-forest to forest (FRA, 2025).
Interactions and interdependencies between forests and climate, including physical, ecological, social, economic and political systems, taking into account the role of forests in mitigating – adapting to climate and environmental change.
Average annual standing volume of all trees, living or dead, measured overbark to a minimum diameter of 0 cm (d.b.h.) that are felled during the given reference period, including the volume of trees or parts of trees that are not removed from the forest, other wooded land or other felling site.
Includes: silvicultural and pre-commercial thinnings and cleanings left in the forest; and natural losses that are recovered (harvested) (TBFRA, 2000).
Land spanning more than 0.5 hectares with trees higher than 5 meters and a canopy cover of more than 10 percent, or trees able to reach these thresholds in situ. It does not include land that is predominantly under agricultural or urban land use (FRA, 2025).
Forests where there are no environmental, social or economic restrictions that could have a significant impact on the current or potential supply of wood. These restrictions could be based on legal acts, managerial owners’ decisions or other reasons (FRA, 2025).
Damage to the chemical, biological and/or physical structure of a soil (soil degradation) and to the forest itself (forest degradation), as a result of incorrect use or management, and which, if not ameliorated, will reduce or destroy the production potential of a forest ecosystem (in perpetuity) (IUFRO, n.d.).
A forest ecosystem is a dynamic complex of plant, animal, and micro-organism communities, and their abiotic environment interacting as a functional unit, where the presence of trees is essential. Humans, with their cultural, economic, and environmental needs are an integral part of many forest ecosystems (CBD, 2001).
Forest ecosystem services (FES) are a subset of the broader category of ecosystem services (ES). Ecosystem services encompass all the benefits that natural ecosystems provide to humans, while forest ecosystem services specifically refer to those benefits derived from forest ecosystems (Brockerhoff et al., 2017). They include:
(A) Supporting services that maintain the conditions for life on Earth, e.g., biodiversity, and genetic diversity,
(B) Provisioning services, e.g., preservation and enhancement of carbon stocks and sinks, renewable resources for a circular and sustainable bioeconomy,
(C) Regulating and maintenance services, e.g., regulation of climate, soil quality and hydrological processes and
(D) Cultural services, e.g., spiritual, recreational and cultural benefits.
An entry point for sharing information with the forest community on Europe’s forest environment, its state and development. FISE brings together data, information and knowledge gathered or derived through key forest-related policy drivers.
“a planned process that aims to regain ecological integrity and enhance human wellbeing in deforested or degraded landscapes”
(WWF and IUCN, 2000).
The practical application of biological, physical, quantitative, managerial, economic, social and policy principles to the regeneration, utilization, and conservation of forests to meet specified goals and objectives while maintaining the productivity of the forest (IUFRO, n.d.).
All the information (in the form of text, maps, tables and graphs) collected during (periodic) forest inventories and condensed into a written scheme of management aiming at continuity of policy and action and controlling the treatment of a forest (IUFRO, n.d.).
They are all the specific actions that are taken in forest management, to achieve specific goals, such as promoting environmental sustainability, enhancing economic viability, or supporting local communities. These actions can vary from light to heavy interventions and utilize different methods and tools according to the type of forest (natural or planted forest systems).
A defined area of land that forms the basic area for planning and management purposes. Usually, management units are the basis of detailed plans and actions. They may be further divided into smaller divisions, such as compartments or sub-compartments, and may themselves be part of a larger planning unit or similar designation (IUFRO, n.d.).
A forest species is defined as a species that is dependent on a forest for part or all of its daily living requirements, or for its reproductive needs. Therefore, an animal species may be considered a forest species even if it does not live most of its life in a forest (based on MCPFE, 2003).
“A forest stand is a contiguous community of trees sufficiently uniform in composition, structure, age, size, class, distribution, spatial arrangement, site quality, condition, or location to distinguish it from adjacent communities. A forest is a “collection of stands” also utilizing the practices of forestry.”
(Sources: Nyland, Ralph D. (2007). Silviculture: concepts and applications (2nd ed.). Prospect Heights: Waveland Press. And Nyland, Ralph D. (2007). Silviculture: concepts and applications (2nd ed.). Prospect Heights: Waveland Press. p. 5.)
A category of forest defined by its composition, and/or site factors (locality), as categorised in a given area (e.g. continents, nation, region), in a system suitable to its situation (The Montreal Process, 1998).
The sum, by number, basal area or volume, of all living trees, generally over a minimum diameter, in a forest or a specified part of it, indexed in various way but usually in terms of total stem volume or mass (IUFRO, n.d.).
The component of the climate system comprising liquid surface and subterranean water, such as in oceans, seas, rivers, freshwater lakes, underground water, wetlands, etc. (IPCC, 2021).
Community representatives who act as full partners with researchers to design, implement and evaluate research for the benefit of the community.
Land cover datasets define the spatial distribution of land surface characteristics, which determine land-atmosphere exchange processes (Hoffmann et al. 2023).
The category of the greenhouse gas inventories where emissions and removals occurring on land and not included in any other sector, are captured.
A key vegetation structural variable measuring leaf surface area relative to ground area, reflecting canopy density and foliage extent (based on ECV website).
A human intervention to reduce emissions or enhance the sinks of greenhouse gases (IPCC, 2022).
Indigenous species of animals or plants that naturally occur in a given region or ecosystem. Under climate change, many species colonise new areas where they may become native over time (IPBES, 2019).
Re-establishment of a forest stand by natural means, i.e. by natural seeding or vegetative regeneration. It may be assisted by human intervention, e.g. by preparatory cutting, scarification or fencing to protect against wildlife damage or domestic animal grazing (TBFRA, 2000; FRA, 2025).
Actions to protect, sustainably manage and restore natural or modified ecosystems that address societal challenges effectively and adaptively, simultaneously providing human well-being and biodiversity benefits. (IUCN, 2016).
Actions to protect, sustainably manage and restore natural or modified ecosystems that address societal challenges effectively and adaptively, simultaneously providing human well-being and biodiversity benefits (IUCN, 2016).
The net ecosystem exchange (NEE) rate of CO2 represents the balance of CO2 absorbed by plants during photosynthesis and CO2 released during respiration, a process with occurs in both plants and soils (NASA, 2022).
Forest management practice where no harvesting is conducted.
A forest stand or area consisting of native tree species that have developed, predominantly through natural processes, structures and dynamics normally associated with late seral development a l phases in primary or undisturbed forests of the same type. Signs of former human activities may be visible, but they are gradually disappearing or too limited to significantly disturb natural processes (DG Env, 2023).
Water condensing from the clouds and falling as rain, hail, snow, sleet. This precipitation does not necessarily reach the Earth’s surface as a certain amount evaporates into the atmosphere as it falls (ESA, 2024).
Generation of biomass through photosynthesis.
Conversion to forest of land that has previously contained forests but that has been converted to other uses (IPCC, 2022).
Establishment of forest through planting and/or deliberate seeding on land that, until then, was under a different land use, implies a transformation of land use form non-forest to forest (TBFRA, 2000; FRA 2025).
The act of re-establishing a forest stand by artificial means, either by planting of seedlings or by scattering seed on land already in forest land use. The material used may be of indigenous or introduced origin (FRA, 2025).
A regional climate model is similar to a global climate model in that it simulates the physical processes in the climate system. Regional climate models cover a limited area of the globe and are run at much finer spatial resolution – 1-50 km grid spacing as opposed to 100-300 km grid spacing in a global model – thus they can simulate the interactions between largescale weather patterns and the local terrain.
The relative humidity specifies the ratio of actual water vapour pressure to that at saturation with respect to liquid water or ice at the same temperature (IPCC, 2022).
Datasets in raster layers providing a range of values that represent the probability to find a forest tree species within a pixel.
The capacity of interconnected social, economic and ecological systems to cope with a hazardous event, trend or disturbance, responding or reorganising in ways that maintain their essential function, identity and structure. Resilience is a positive attribute when it maintains capacity for adaptation, learning and/or transformation (Arctic Council, 2016).
Restoration involves human interventions to assist the recovery of an ecosystem that has been previously degraded, damaged or destroyed (IPSS, 2022).
All roundwood felled or otherwise harvested and removed. It comprises all wood obtained from removals, i.e. the quantities removed from forests and from trees outside the forest, including wood recovered from natural, felling and logging losses during the period, calendar year or forest year. It includes all wood removed with or without bark, including wood removed in its round form, or split, roughly squared or in other form (e.g. branches, roots, stumps and burls (where these are harvested) and wood that is roughly shaped or pointed. It is an aggregate comprising wood fuel (including wood for charcoal) and industrial roundwood (wood in the rough) (FRA, 2025).
The flow of water over the surface or through the subsurface, which typically originates from the part of liquid precipitation and/or snow/ ice melt that does not evaporate, transpire or refreeze, and returns to water bodies (IPCC, 2022).
The displacement of the soil by the action of water or wind. Soil erosion is a major process of land degradation (IPCC, 2022).
Water stored in the soil in liquid or frozen form. Root-zone soil moisture is of most relevance for plant activity (IPCC, 2022).
Carbon contained in soil organic matter (IPCC, 2022).
The specific humidity specifies the ratio of the mass of water vapour to the total mass of moist air (IPCC, 2021).
Individuals, organizations or communities that have a direct interest in the process and outcomes of a project, research or policy endeavor.
Stakeholder interactions done within the context of the project (i.e. consult, listen, understand, communicate, influence, negotiate, etc.) with the broader objective of satisfying the needs of the project.
A community of trees possessing sufficient uniformity in composition, age, arrangement or condition to be distinguishable from the forest or other growth on adjoining areas, thus forming a temporary silvicultural or management entity (IUFRO n.d.).
Number of trees per unit area in a forest.
Act of taking care of or managing something.
The stewardship and use of forests and forest lands in a way, and at a rate, that maintains their biodiversity, productivity, regeneration capacity, vitality and potential to fulfil, now and in the future, relevant ecological, economic and social functions, at local, national and global levels, and that does not cause damage to other ecosystems (MCPFE, 1993).
Tree cover density represents the vertical projection of tree crowns onto the horizontal surface of the Earth and provides information on the proportional crown coverage per pixel (EEA website).
Tree species diversity refers to the variety and abundance of different tree species within a given area.
The lowest part of the atmosphere, below the tropopause, where clouds and weather phenomena occur. In the troposphere, temperatures generally decrease with height (IPCC, 2021).
A stand or forest type, consisting of trees of a range of age classes, with age differences which are significant in relation to the stand structure management and rotation length. Defining average stand age is not meaningful. Practised or expected stand management, if any, is continuous forest cover management – selective cuttings, shelter tree cutting, regeneration with small openings etc. (FRA, 2025).
Upper air refers to the earth’s atmosphere above about 1.500 m.
The process by which a user becomes proficient with and integrates a new product, service, or technology into their daily routine or workflow, ultimately leading to long-term, committed use. User adoption relies on stakeholder engagement.
Water vapour is the gaseous phase of water. It is one state of water within the hydrosphere.
Average annual standing volume of all trees, living or dead, measured overbark to a minimum diameter of 0 cm (d.b.h.) that are felled during the given reference period, including the volume of trees or parts of trees that are not removed from the forest, other wooded land or other felling site.
Includes: silvicultural and pre-commercial thinnings and cleanings left in the forest; and natural losses that are recovered (harvested) (TBFRA, 2000).
The mass of the woody parts (wood, bark, branches, twigs, stumps and roots) of trees, alive and dead, shrubs and bushes, measured to a minimum diameter of 0 mm (d.b.h.). Includes: Above-stump woody biomass, and stumps and roots. Excludes: Foliage (TBFRA, 2000).