Mountain regions occupy about one-fifth of the Earth’s surface and provide goods and services to about half of humanity. Accordingly, they received particular attention in the United Nations system, lastly by the UN Declaration for the year 2002 to be the "International Year of Mountains".
The strong altitudinal gradients in mountain regions provide unique and sometimes the best opportunities to detect and analyse global change processes and phenomena because
meteorological, hydrological, cryospheric and ecological conditions change strongly over relatively short distances; thus biodiversity tends to be high, and characteristic sequences of ecosystems and cryospheric systems are found along mountain slopes. The boundaries between these systems experience shifts due to environmental change and thus may be used as indicators of such changes.
the higher parts of many mountain ranges are not affected by direct human activities. These areas include many national parks and other protected environments. They may serve as locations where the environmental impacts of climate change alone, including changes in atmospheric chemistry, can be studied directly.
mountain regions are distributed all over the globe, from the Equator almost to the poles and from oceanic to highly continental climates. This global distribution allows us to perform comparative regional studies and to analyse the regional differentiation of environmental change processes as characterized above.
Therefore, within the IGBP an Initiative for Collaborative Research on Global Change and Mountain Regions was developed, which strives to achieve an integrated approach for observing, modelling and investigating global change phenomena and processes in mountain regions, including their impacts on ecosystems and socio-economic systems.
The ultimate objectives of the Initiative are
to develop a strategy for detecting signals of global environmental change in mountain environments;
to define the consequences of global environmental change for mountain regions as well as lowland systems dependent on mountain resources (highland-lowland interactions); and
to make proposals towards sustainable land, water, and resource management for mountain regions at local to regional scales.
To achieve the above objectives, the research under the Mountain Initiative will be structured around four Activities, each of which is divided into a small number of specific Tasks:
Activity 1: Long-term monitoring and analysis of indicators of environmental change in mountain regions
This Activity will be accomplished through the coordination of ongoing research and, where required, the initiation of new projects in mountain regions around the world. A set of four mountain-specific indicator groups of environmental change is considered:
Cryospheric indicators related to snow conditions, glaciers, permafrost and solifluction processes (Task 1.1);
Terrestrial ecosystems, particularly mountain plant communities and soils (Task 1.2);
Freshwater ecosystems, in particular high mountain streams and lakes (Task 1.3);
Watershed hydrology, i.e. water balance components of high mountain waterhsheds/headwater basins (Task 1.4).
Contemporary monitoring will be arranged within the context of reconstructions of longer-term past trends and variability, provided through close collaboration with relevant aspects of the IGBP core project PAGES.
Activity 2: Integrated model-based studies of environmental change in different mountain regions
To achieve the overall goals of the Initiative, it is necessary to develop a framework that permits to analyse and predict hydrological and ecological characteristics and their linkages with land use and climate at various spatial and temporal scales. Accordingly, this Activity is organized in the following four research themes:
Development of coupled ecological, hydrological and land use models for the simulation of land cover and land surface processes in complex mountain landscapes and river basins under current and changing atmospheric and socio-economic conditions (Task 2.1);
Development of regional scale atmospheric models for mountain regions capable of providing high resolution areal distribution patterns of atmospheric driving forces, in particular precipitation, for the study of land surface processes (Task 2.2);
Integrated analysis of environmental change in mountain regions by means of fully coupled land surface-atmosphere models, where feasible and appropriate, or by qualitative assessments (Task 2.3);
Regional scale mountain land surface experiment to support the development, application and validation of the above models (Task 2.4).
Activity 3: Process studies along altitudinal gradients and in associated headwater basins
Ecological and hydrological field studies and experiments, including manipulative ones, along altitudinal gradients and at sensitive sites can provide invaluable data on potential responses of mountain ecosystems to anthropogenically induced environmental change as well as increasing understanding of the associated biotic feedbacks. They are also required to support modelling (Activity 2) and for the identification of indicators of global change. Research themes to be addressed within this Activity include:
Development of indicators of mountain ecosystem response to environmental forcing factors, based on an improved process understanding of these unique systems insofar as they are sensitive to global change forcings and for a process-related interpretation of historical and paleorecords (Task 3.1);
Assessment of runoff generation and flowpath dynamics on steep hillslopes and in headwater catchments, including the examination of the role of biogeochemical ‘hot spots’, for instance for N transformation in mountain areas (Task 3.2);
The relationship between diversity and ecosystem function, taking advantage of the strong changes of diversity along altitudinal gradients and an assessment of the associated changes in ecosystem functions (Task 3.3).
Paleo-archives will be used to explore system responses to both natural variability and anthropogenic impacts.
Activity 4: Sustainable land use and natural resources management
The overall objective of this Initiative is to evaluate and enhance sustainable land, water, and resource management strategies for mountain regions. Three priority areas are suggested for assessment:
Changes in forest resources, with potential implications for agriculture, rates of erosion and magnitude of floods, and biodiversity (Task 4.1);
Intensification and/or extensification of agriculture (including grazing), with potential implications for food security, rates of erosion and magnitude of floods, and biodiversity (Task 4.2);
Changes in water resources due to factors such as changing agricultural practices, increasing temporary or permanent population, and/or increasing energy generation, with implications for downstream water supply, energy availability, flooding, and sediment transfer (Task 4.3).
Work on these linked themes will include paleo-research, local knowledge and scientific investigation, e.g. with respect to evaluating optimal combinations of traditional and innovative land use and resource management systems.
