A cloud forest, also called a water forest, primas forest, or tropical montane cloud forest, is a generally tropical or subtropical, evergreen, montane, moist forest characterized by a persistent, frequent or seasonal low-level cloud cover, usually at the canopy level, formally described in the International Cloud Atlas (2017) as silvagenitus. Cloud forests 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.
Tree ferns in a cloud forest on Mount Kinabalu, Borneo
Stratus silvagenitus clouds in Uva Province, Sri Lanka
One of the hanging bridges of the Sky walk at the Monteverde Cloud Forest Reserve in Monteverde, Costa Rica disappearing into the clouds
Bryophyte-covered mossy forest at Mount Dulang-dulang, Philippines
Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures fall as elevation increases, causing the ecosystem to stratify. This stratification is a crucial factor in shaping plant community, biodiversity, metabolic processes and ecosystem dynamics for montane ecosystems. Dense montane forests are common at moderate elevations, due to moderate temperatures and high rainfall. At higher elevations, the climate is harsher, with lower temperatures and higher winds, preventing the growth of trees and causing the plant community to transition to montane grasslands and shrublands or alpine tundra. Due to the unique climate conditions of montane ecosystems, they contain increased numbers of endemic species. Montane ecosystems also exhibit variation in ecosystem services, which include carbon storage and water supply.
A subalpine lake in the Cascade Range, Washington, United States
A stand of mountain birch at around 750 m in Trollheimen, typical of Scandinavian subalpine forests
Waimea Canyon, Hawaii, is known for its montane vegetation.
Temperate montane forest in Bavaria, Germany