A subalpine lake in the Goms district of the Swiss Alps.

Montane ecology is the branch of ecology that studies life systems on mountains or other high elevation regions on the Earth. The ecosystems on mountains is strongly affected by climate, which gets colder as elevation increases. Because of this, mountain ecosystems form life zones, which are stratified according to elevation. Dense forests are common at moderate elevations. However, as the elevation increases, the climate becomes harsher, and the plant community transitions to grasslands or tundra.

Life zones[link]

As elevation increases, the climate becomes cooler and wetter, due to the lower air pressure. Due to the harsher climate, the dominant lifeforms on mountains is different from that of surrounding lowlands. The characteristic flora and fauna in the mountains tend to strongly depend on elevation. This dependency causes life zones to form: bands of similar ecosystems at similar altitude.

One of the typical life zones on mountains is the montane forest: at moderate elevations, the rainfall and temperate climate encourages dense forests to grow. Holdridge defines the climate of montane forest as having a biotemperature of between 6 and 12 °C (43 and 54 °F), where biotemperature is the mean temperature considering temperatures below 0 °C (32 °F) to be 0 °C (32 °F).^[1] Above the elevation of the montane forest, the trees thin out in the subalpine zone, become twisted krummholz, and eventually fail to grow. The elevation where trees fail to grow is called the treeline. The biotemperature of the subalpine zone is between 3 and 6 °C (37 and 43 °F).^[1]

A stand of mountain birch at around 750 m in Trollheimen, typical of Scandinavian subalpine forests

Above the treeline the ecosystem is called the alpine zone or alpine tundra, dominated by grasses and low-growing shrubs. The biotemperature of the alpine zone is between 1.5 and 3 °C (35 and 37 °F). Alpine zones around the globe share some common characteristics. Many different plant species live in the alpine environment. These include perennial grasses, sedges, forbs, cushion plants, mosses, and lichens.^[2] Alpine plants must adapt to the harsh conditions of the alpine environment, which include low temperatures, dryness, ultraviolet radiation, and a short growing season. Because of the common characteristics of these zones, the World Wildlife Fund groups a set of related ecoregions into the "montane grassland and shrubland" biome.

Climates with biotemperatures below 1.5 °C (35 °F) tend to consist purely of rock and ice.^[1]

Montane forests[link]

Tropical montane forest at around 2,000 m in Malaysia

Montane forests occur between the submontane zone and the subalpine zone. The exact elevations at which one habitat changes to another vary across the globe, particularly by latitude. The upper limit of montane forests is often marked by a change to hardier species, which occur in less dense stands. The transition to open forest is known as the timberline.^[3] For example, in the Sierra Nevada of California, the montane forest has dense stands of Lodgepole pine and Red fir, while the Sierra Nevada subalpine zone contains sparse stands of whitebark pine.^[4]

The upper limit of the montane forest often tracks the elevation of the treeline itself. There may also be a "lower timberline", which separates the montane zone from drier steppe or desert region.^[3] In tropical regions of Southeast Asia the tree line may be above 4,000 m (13,000 ft),^[5] whereas in Scotland it may be as low as 450 m (1,480 ft).^[6]

The climate of montane forests is colder than lowland climate at the same latitude, so the montane forests often have species typical of higher-latitude lowland forests.^[7] Montane forests differ from lowland forests in the same area.^[8] Humans can disturb montane forests through forestry and agriculture.^[8] On isolated mountains, montane forests surrounded by treeless dry regions are typical "sky island" ecosystems.^[9]

One example of a montane forest is a cloud forest, which gains its moisture from clouds and fog.^[10] Cloud forests are typically tropical or subtropical evergreen forests. They often exhibit an abundance of mosses covering the ground and vegetation, in which case they are also referred to as mossy forests. Mossy forests usually develop on the saddles of mountains, where moisture introduced by settling clouds is more effectively retained.^[11]

Montane forests often contain tree indicator species: common species whose range boundaries matches the boundaries of the zone. These indicator species include:

This list is incomplete; you can help by expanding it.

• Lodgepole pine
• Red fir
• Pacific silver fir^[12]
• Grand fir^[13]

Subalpine zone[link]

Subalpine Fir in Mount Rainier National Park, Washington, United States

The subalpine zone is the biotic zone immediately below tree line around the world. Species that occur in this zone depend on the location of the zone on the Earth, for example, Snow Gum in Australia, or Subalpine Larch, Mountain Hemlock and Subalpine Fir in western North America.

Trees in the subalpine zone often become krummholz, that is, crooked wood, stunted and twisted in form. At treeline, tree seedlings may germinate on the lee side of rocks and grow only as high as the rock provides wind protection. Further growth is more horizontal than vertical, and additional rooting may occur where branches contact the soil. Snow cover may protect krummholz trees during the winter, but branches higher than wind-shelters or snow cover are usually destroyed. Well-established krummholz trees may be several hundred to a thousand years old.^[14]

Montane grasslands and shrublands may be found in the subalpine zone. Tuolumne Meadows in the Sierra Nevada of California, USA, is an example of a subalpine meadow.

Example subalpine zones around the world include the French Prealps in Europe, the Sierra Nevada and Rocky Mountain subalpine zones in North America, and subalpine forests in the eastern Himalaya, western Himalaya, and Hengduan mountains of Asia.

Alpine grasslands and tundra[link]

Flora of an alpine environment

Alpine grasslands and tundra lie above the treeline, in a world of intense radiation, wind, cold, snow, and ice. As a consequence, alpine vegetation is close to the ground and consists mainly of perennial grasses, sedges, and forbs. Annual plants are rare in this ecosystem and usually are only a few inches tall, with weak root systems.^[15] Other common plant life-forms include prostrate shrubs, graminoids forming tussocks, and cryptogams, such as bryophytes and lichens.^[2]

Plants have adapted to the harsh alpine environment. Cushion plants, looking like ground-hugging clumps of moss, escape the strong winds blowing a few inches above them. Many flowering plants of the alpine tundra have dense hairs on stems and leaves to provide wind protection or red-colored pigments capable of converting the sun's light rays into heat. Some plants take two or more years to form flower buds, which survive the winter below the surface and then open and produce fruit with seeds in the few weeks of summer.^[16]

Alpine meadows form where sediments from the weathering of rocks has produced soils well-developed enough to support grasses and sedges. Non-flowering lichens cling to rocks and soil. Their enclosed algal cells can photosynthesize at any temperature above 0 °C (32 °F), and the outer fungal layers can absorb more than their own weight in water. The adaptations for survival of drying winds and cold may make tundra vegetation seem very hardy, but in some respects the tundra is very fragile. Repeated footsteps often destroy tundra plants, leaving exposed soil to blow away, and recovery may take hundreds of years.^[16]

An alpine mire in the Swiss Alps

Alpine grasslands are common enough around the world to be categorized as a biome by the World Wildlife Fund. The biome, called "Montane grasslands and shrublands," often evolved as virtual islands, separated from other montane regions by warmer, lower elevation regions, and are frequently home to many distinctive and endemic plants which evolved in response to the cool, wet climate and abundant sunlight.

The most extensive montane grasslands and shrublands occur in the Neotropic Paramo of the Andes Mountains. This biome also occurs in the mountains of east and central Africa, Mount Kinabalu of Borneo, highest elevations of the Western Ghats in South India and the Central Highlands of New Guinea. A unique feature of many wet tropical montane regions is the presence of giant rosette plants from a variety of plant families, such as Lobelia (Afrotropic), Puya (Neotropic), Cyathea (New Guinea), and Argyroxiphium (Hawaii).

Where conditions are drier, one finds montane grasslands, savannas, and woodlands, like the Ethiopian Highlands, and montane steppes, like the steppes of the Tibetan Plateau.

See also[link]

Wikimedia Commons has media related to: Montane ecoregions

• Mountain
• Temperate coniferous forests
• Sierra Nevada lower montane forest
• East African montane forests
• Afromontane, a series or high-elevation regions in Africa
• California montane chaparral and woodlands, an ecoregion.
• Angolan montane forest-grassland mosaic, an ecoregion.
• Australian Alps montane grasslands, an ecoregion.
• South Western Ghats montane rain forests, an ecoregion

References[link]

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Sub Focus
Background information
Birth name	Nick Douwma
Origin	Guildford, England
Genres	Drum and bass, dubstep, house, electro
Occupations	Songwriter, musician, audio mixing, record producer, DJ
Years active	2003–present
Labels	Ram Records
Associated acts	Pendulum, TC, Danny Wheeler, Coco Sumner, The Prodigy, Chase & Status
Website	subfocus.com

Nick Douwma, better known by his stage name Sub Focus, is an English Electronic Music record producer. He has been releasing records since 2003.^[1] On 12 October 2009, he released his self-titled debut album. He plans to release a second album in 2012.^[2]

Chart success[link]

In March 2005 he had a number one single on the UK Dance Chart with "X-Ray / Scarecrow". The single reached number 60 on the UK Singles Chart.^[3] In June 2008, he hit number one on the UK Dance Chart again with "Timewarp / Join the Dots". In August 2009, he cracked the UK Top 40 for the first time with "Rock It / Follow the Light", which reached number 38.^[4] "Rock It / Follow the Light" also got him a third UK Dance Chart #1, as well as reaching the B-List of BBC Radio 1's playlist.

Sub Focus has also remixed selected works of The Prodigy, Deadmau5, Rusko, Dr. Octagon, Empire of the Sun and Dizzee Rascal.

On 6 October 2009, Sub Focus released "Smooth" which was free to download.

In 2010, Sub Focus was a support act for Australian drum & bass band Pendulum on their UK tour to promote their third album Immersion.^[5] Later that year, he produced the Example track "Kickstarts" for his second album, Won't Go Quietly. The track was successful in the UK Singles Chart, peaking at #3.^[6] This makes it Sub Focus' most commercially successful production to date.

Discography[link]

Albums[link]

Singles[link]

[A] "Falling Down will be re-released. It will consist of the original version, VIP Mix, xKore Remix & Nick Thayer Remix.

Remixes[link]

Guest appearances and collaborations[link]

VIP mixes[link]

References[link]

External links[link]

• Sub Focus on Myspace
• Sub Focus on Facebook
• Sub Focus on Twitter
• Sub Focus discography at Discogs