Mountain forests

Posted: 9 May 2008

Mountain forests play many vital roles for people. Among the most critical, in these water towers of the world, is their role in capturing and storing rainfall, maintaining water quality, regulating river flow, and reducing erosion and downstream sedimentation.

The endangered Monkey Puzzle tree of Chile.
The endangered Monkey Puzzle tree of Chile.
The endangered monkey puzzle tree (Araucaria araucana) of Chile. A. araucana forests have been rapidly destroyed and degraded due to logging, fire and grazing. The declaration of the monkey puzzle tree as a Natural Monument in Chile means that logging of the species is now forbidden. ©Global Trees Campaign/Cristian Echeverria
Mountain forests are, also, important sources of wood and other forest products, reflecting their high biodiversity. They also provide many environmental services, including protection against natural hazards and landscapes for tourism and recreation, and absorption of greenhouse gases from the atmosphere.
  • Mountain forests cover just over 9 million sq. km: 28 per cent of the world's closed forest area. Over 4 million sq. km. of mountain forests are coniferous needle-leaf forests, and the remainder is broadleaved, including about 2 million sq. km. of moist tropical forest. Just over 5 million sq. km. of mountain forest are below 1000 m. The global distribution of different types of mountain forests is shown in the maps provided by the World Conservation Monitoring Centre's Mountain Programme.

  • Globally, the fastest rate of loss of any forest type is for tropical montane (mountain) forests, at 1.1 per cent per year. While forests in the mountains of developing countries are generally decreasing in area, those in industrial nations are expanding: Switzerland's forest area has increased by 60 per cent since the main period of deforestation ended in the 1860s.

  • Tropical montane cloud forests are one of the world's most threatened ecosystems. Most of the 600 sites that remain globally are fragments. They are particularly important for 'stripping' water from cloud, adding about 15 per cent to rainfall in humid climates, and up to 100 per cent in areas with low rainfall. They have high levels of biodiversity, with very high proportions of endemic species, including tree ferns (Cyatheaceae), bromeliads (Bromeliaceae), and orchids (Orchidaceae). Local people use them for fuelwood, building materials, food and medicine. Because of their dependence on the stable position of clouds, they are particularly threatened by climate change.

  • Forests cover over 60 per cent of Bhutan, changing with increasing altitude from subtropical forests at the lowest altitudes to open juniper and rhododendron scrub at 4,000-4,500 m. They support much of the country's biodiversity: 160 species of mammals, 770 of birds, and 5,400 of vascular plants.

  • The environmental services provided by mountain forests to society are recognised by legislation in many countries. In Costa Rica, where forests cover 40 per cent of the country's area, and 60 per cent of these are private, the 1996 Forestry Law requires hydroelectricity corporations to pay forest landowners for reforestation and forest management and conservation, valued at US$5 to US$70 per hectare per year. Different companies pay US$ 10 to 40 per hectare per year.

    The Qomolangma Nature Preserve, Tibet.
    The Qomolangma Nature Preserve, Tibet.
    The Qomolangma Nature Preserve in Tibet extends from the lush valleys of the Himalaya bordering Nepal to the high, cold dry alpine plateau regions. © The Mountain Institute

  • In 1997, US$ 14 million was paid for environmental services, resulting in the reforestation of 6,500 ha, the sustainable management of 10,000 ha, and the preservation of 79,000 ha of private natural forest. In Switzerland, where 80 per cent of forests are in mountains, the government pays forest owners US$ 25-30 million per year for managing their forests, mainly for protection against natural hazards such as avalanches and landslides.

  • The highest-growing tree in the world is the quenual (Polylepis spp.), which grows up to an altitude of nearly 5,000 m in the Peruvian Andes. Only 2 per cent of the area once covered by these trees is still forested, due to human-induced fires, the domestication of grazing animals such as llama and alpaca, and major climatic events.

  • Confucius said that "Man can live without meat but cannot live without bamboo". Seven million hectares of bamboo grow in China's mountains. In 1997, the bamboo sector generated US$ 2.2 billion, including exports worth over US$ 320 million, 25 per cent of China's forest exports. 5.6 million people, including 4.5 million farmers, work in this sector. Bamboo is used for furniture, paper, ply-bamboo, food, medicine, and handicrafts.

  • After centuries of exploitation, the walnut-fruit forests of southern Kyrgyzstan have been reduced from 1.5 million to less than 30,000 hectares.

  • Around 90 per cent of mountain forests have disappeared from the northern Andes.

Sources:

M.F. Price and N. Butt (editors) (2000) Forests in Sustainable Mountain Development, CABI, Wallingford.

Mountain Agenda (2000) Mountains of the World: Mountain Forests and Sustainable Development, Mountain Agenda, Bern.

Compiled by Dr Martin Price, Director of the Centre for Mountain Studies at Perth College, within Scotland's UHI Millennium Institute, 'creating the University of the Highlands and Islands'.