Building on modelling efforts and experimental sites, in the next months and years MOUNTFOR provides forecasts of specific changes across Europe and overseas, which in turn provides the scientific basis for developing descriptions of future ecosystem conditions in mountain environments.
This derives from the necessity to emphasize the local and regional vulnerabilities of ecosystem components or processes to climate variability and change, thresholds at which specific forest or hydrologic ecosystems may experience state changes, and uncertainties associated with the forecasts. These outcomes provide scenarios of future ecosystem conditions, which help identifying adaptation options. Research infrastructures are incorporated in a range of tools and strategies for adapting to climate change and its effects, driven by the goal of maintaining critical ecosystem structures and functions, along with associated native biodiversity.
MOUNTFOR applies an integrated ecosystem approach to research how mountain ecosystems respond, now and in the future, to climate variability and change. Understanding how mountain forests respond to climate change is essential to natural resource management, and including climate change effects in management planning and implementation might reduce damage to water resources. Climate change requires resource managers to adapt how they think about forest ecosystems. Broad-scale climate drivers can induce region-wide responses, but directional changes in systems must be distinguished from sources of variability related to normal climate variation and other factors. Long-term studies identifying regional responses in disturbance patterns, vegetation dynamics, and catchment hydrology caused by the combination of climate patterns, topographic complexity, and landscape controls need to be complemented for mountain regions. The investigation of spatial and temporal aspects of ecosystem dynamics, with emphasis on understanding and distinguishing processes controlled by climate versus processes modulated by local or regional characteristics, need to be directed to develop and synthesize empirical and modelled results to infer the resilience of mountain forests to climate change, establishing hub for a worldwide mountain forest partnership, within the strategy of EFI.
While a relatively small proportion of Europeans actually lives in the mountains, they are of vital importance to the continent’s population in many ways. Perhaps most important is the role of mountains as water towers, intercepting water from air masses and storing it either as snow or in lakes and reservoirs. Mountain forests strongly influence both the quantity and quality of water supplies to mountain and lowland communities and industries. European mountains see changes in ecosystem processes primarily from climate-forced changes in water dynamics. With earlier snowmelt and increasing proportions of rain versus snow, drought stress increases. Cascading effects include increasing vegetation mortality, dieback of entire forest stands, longer and more intense fire seasons, and increasing susceptibility to insects and pathogens. Climate model projections suggest more pronounced phenomena in coming years. Climate-forced changes in hydrology at high elevations are caused by temperature-driven changes in winter precipitation form and snowmelt and by direct summer warming. Permanent snow and glaciers are retreating rapidly. Water chemistry is changing as weathering rates increase and new sediments are exposed. Increased stream temperature and decreased summer flow are strongly affecting mountain aquatic ecosystems.
As forests have the highest carbon density of all terrestrial ecosystems and as the forest cover on managed land increases with altitude, the carbon pool of mountain forests, both below and above ground, is high.
Natural forest dynamics are driven particularly by climate factors. Under increasingly favourable climate conditions, the major constraints to forest growth at high altitudes – short growing seasons and low temperatures – are being alleviated and the timberline is moving upwards, at least where the soil and precipitation conditions are suitable and there is little grazing or cutting. Superimposed on this tendency are changes in land use practices. While rising temperatures benefit the growth of trees, they also facilitate the more rapid growth and expansion of populations of pests and disease-causing organisms.
The role of mountain forests in the mitigation of climate change is rather passive. To avoid the release of large amounts of CO2 into the atmosphere, their protection, conservation and management are important.
Another important field of mitigation is the substitution of fossil fuels with renewable forms of energy. Given growing energy demands, all efforts to increase the efficient use of energy are important, so that key needs are to ensure that traditional fuel-wood and sources of bio-fuel are used more efficiently. Reactive adaptation to climate change includes changes in harvesting levels and schedules, the management of downed trees after storms and deadwood, and the development of socioeconomic support programmes for communities experiencing negative impacts. Planned adaptation implies the redefinition of agro-forestry goals and practices, taking into consideration the risks and uncertainties associated with climate change.