Environment

What Is A Cloud Forest?

Cloud forests are forests where cloud cover persists permanently or temporarily at low levels, usually at the canopy level of the forest.

Description Of A Cloud Forest

A cloud forest is subtropical or tropical evergreen montane moist forest with high levels of mist or cloud cover mostly at the canopy level of vegetation. All year cloud forests have almost 100 percent humidity according to the University of Illinois study. In the humid tropics, montane cloud forests are found at an altitude of between 500 and 3,500 meters, according to a United Nations University report. But there are cloud forests in altitudes of 5,005 metres, according to a 2010 Hydrological Processes study by the Cambridge University.

In eastern Panama, cloud forests are at an altitude of 750 meters, and 2200 meters on higher mountains in western Panama, according to a study by the American Museum of Natural History. Cloud forest climates vary depending on location, but their average temperature is 17.7 °C, and average annual rainfall is estimated at 2,200mm, according to the 2010 Hydrological Processes study by Cambridge University.

Hydrological Processes

In cloud forests, vegetation is covered by clouds seasonally or year round. The cloud cover enables the vegetation to capture moisture and retain it in a process called horizontal precipitation. This process enables cloud forests to flourish even in the dry seasons, according to La Hesperia biological station. Cloud forests also trap water from wind-blown mist and clouds (which would not have fallen as rain) in a process called lateral cloud filtering. In some instances this cloud filtration accounts for half the annual precipitation that occurs in cloud forests according to Community Cloud Forest Conservation.

Importance Of Cloud Forests

Cloud forests are natural water towers that provide billions of people with fresh and clean water. The cloud filtration that happens in them increases ground and surface water. The La Tigra National Park cloud forest in the mountains above Tegucigalpa, Honduras is only 18km by 16km in area. Yet this forest provides 40 percent of water used in capital city of Tegucigalpa with 1.25 million people according to Community Cloud Forest Conservation study.

Cloud forests are also inhabited by the indigenous people who depend on the forest for their livelihood. In Ecuador, cloud forests provide habitat to the jaguar, sloth, howler monkey, puma and the spectacled bear. In tropical montane cloud forests, the horizontal rain provides up to 50 percent of water that humans, animals, and vegetation rely on. They also provide food for birds; an estimated 35 and 45 percent of birds feed on fruits in cloud forests.

Vegetation Of Cloud Forests

Cloud forests have abundant vegetation and at least 80 percent of has not been documented according to National Geographic. These forests have abundant mosses covering the ground and are thus often called mossy forests. This moss develops due to moisture being retained by the cloud forests according to the Rainforests study. Cloud forests also have high number of epiphyte plants like lichens, orchids, ferns, bromeliads, as well as the woody climbing plant species. The epiphytes grow on tree trunks and branches, They serve microhabitats for invertebrates and amphibians.

Endemism In Cloud Forests

There are epiphyte plants and animal species in cloud forests that are highly endemic. Research done in Guatemala cloud forests led to the discovery of the horned passalus beetle (Coleoptera: Passalidae) unique to that habitat, according to Community Cloud Forest Conservation report. There are also endemic birds in Central American cloud forests. These birds are vital for seed dispersal. Studies done in cloud forests report 30 to 50 percent of tree and woody species there depend on birds for seed dispersal according to Community Cloud Forest Conservation.

Some endemic bird species in Central American cloud forests are ocellated quail, bearded screech owl, belted flycatcher, pink-headed warbler, and the black-capped siskin. These birds are among the 38 endemic species found in the Americas' cloud forests according to a UNEP study. Studies also show 10 percent of the world’s 2609 restricted range bird species with a range of lesser than 50,000 kilometers are found in cloud forests. There also are tiny animals like olinguito raccoon endemic to Colombia and Ecuador cloud forests, golden toad endemic to Monteverde cloud forests, the Blue-capped Motmot bird and tree frog found only in Veracruz Mexico and Honduras cloud forests. In the US, the El Yunque National Forest, a cloud forest has endemic plant species like the Roble de Sierra, Spanish lime, Guayabota De Sierra, and the Camasey.

Worldwide Occurrence Of Cloud Forests

Cloud forests worldwide make up less than 2.5 percent of the world’s tropical forests according to a study by UNEP. Tropical and subtropical cloud forests are present in countries like Australia, Bolivia, Brunei, Pakistan, Brazil, Burundi, Colombia, Cambodia, Cameroon, Costa Rica, Dominican Republic, DR Congo, El Salvador, Ecuador, Fiji, Guatemala, Gabon, Guyana, Honduras, India, Indonesia, Jamaica, Kenya, Malaysia, Mexico Madagascar, Micronesia, Myanmar, Mozambique, Nicaragua, Panama, Oman, Papua New Guinea, Peru, Rwanda, Philippines, Sri Lanka, Tanzania, Trinidad and Tobago, US, Vietnam and Venezuela.

Threats To Cloud Forests

Besides changes in climate, cloud forests worldwide face threats. With rapidly growing populations worldwide, the need to grow more food is resulting in encroachment of these forests by people for subsistence farming. Wood harvesting for fuel and commercial logging are other threats to cloud forests. There is also the exploitation of non-wood forest products which interfere with the forests’ delicate biosphere. The introduction of non-native species is also interfering with cloud forests' ecological balance. Industrialization, drug cultivation, tourism, construction of media and telecommunication facilities are also contributing to cloud forest destruction.

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