is the branch of forestry (London Jobs) concerned with the overall administrative, economic, legal, and social aspects and with the essentially scientific and technical aspects, especially silviculture, protection, and forest (London Jobs) regulation. This includes management for aesthetics, fish, recreation, urban values, water, wilderness, wildlife, wood products, forest (London Jobs) genetic resources and other forest (London Jobs) resource values. Management can be based on conservation, economics, or a mixture of the two. Techniques include timber extraction, planting and replanting of various species, cutting roads and pathways through forests (London Jobs), and preventing fire.
Public input and awareness (London Jobs)
There has been an increased public awareness of natural resource policy, including forest (London Jobs) management. Public concern regarding forest (London Jobs) management may have shifted from the extraction of timber to the preservation of additional forest resources, including wildlife and old growth forest (London Jobs), protecting biodiversity, watershed management, and recreation. Increased environmental awareness may contribute to an increased public mistrust of forest (London Jobs) management professionals.
Many tools like GIS modelling have been developed to improve forest (London Jobs) inventory and management planning
Wildlife considerations (London Jobs)
The abundance and diversity of birds, mammals, amphibians and other wildlife are affected by strategies and types of forest (London Jobs) management.
A cloud forest (London Jobs), also called a fog forest (London Jobs), is a generally tropical or subtropical evergreen montane moist forest (London Jobs) characterized by a persistent, frequent or seasonal low-level cloud cover, usually at the canopy level. Cloud forests (London Jobs) often exhibit an abundance of mosses covering the ground and vegetation, in which case they are also referred to as mossy forests (London Jobs). Mossy forests (London Jobs) usually develop on the saddles of mountains, where moisture introduced by settling clouds is more effectively retained.
Distribution and climate (London Jobs)
Dependent on local climate, which is affected by the distance to the sea, the exposition and the latitude, the altitude varies from 500 m to 4000 m above sea level. Typically, there is a relatively small band of altitude in which the atmospheric environment is suitable for cloud forest (London Jobs) development. This is characterized by persistent mist or clouds at the vegetation level, resulting in the reduction of direct sunlight and thus of evapotranspiration. Within cloud forests (London Jobs), much of the precipitation is in the form of fog drip, where fog condenses on tree leaves and then drips onto the ground below.
Tropical cloud forests (London Jobs) extend from 23°N to 25°S latitudes and occur in a relatively narrow altitudinal zone with a special atmospheric environment which is characterized by at the vegetation level. Annual rainfall can range from 500 to 10000 mm/year and mean temperature between 8 to 20°C.
While cloud forest (London Jobs) today is the most widely used term, in some regions these ecosystems or special types of cloud forests (London Jobs) are called mossy forest (London Jobs), elfin forest (London Jobs), montane thicket, dwarf cloud forest (London Jobs), nuboselva, bosque montano nebuloso, selva de neblina, bosque nuboso, bosque de ceja, selva sublada, nebelwald, wolkenwald, forêt (London Jobs) néphéliphile, forêt (London Jobs) de nuage, unmu-rin, bosque anao, foresta (London Jobs) nebular, mata nebular, matinha nebular, floresta (London Jobs) fe neblina, floresta (London Jobs) nuvigena, mata de neblina, matinha de altitude, floresta (London Jobs) nublada, and floresta (London Jobs) pluvial montana e/ou alto montana.
The definition of cloud forest (London Jobs) can be ambiguous, with many countries not using the term (preferring such terms as Afromontane forest (London Jobs) and upper montane rain forest (London Jobs), or more localised terms such as the Bolivian yungas, and the laurisilva of the Atlantic Islands), and occasionally subtropical and even temperate forests (London Jobs) in which similar meteorological conditions occur are considered to be cloud forests (London Jobs).
Only 1% of the global woodland is covered by cloud forests (London Jobs).
Important areas of cloud forest (London Jobs) are in Central- and South America, East- and Central Africa, Indonesia, Malaysia, at the Philippines, Papua-New Guinea and in the Caribbean.
Temperate cloud forests (London Jobs)
Although far from being universally accepted as true cloud forests (London Jobs), several forests (London Jobs) in temperate regions have strong similarities with tropical cloud forests (London Jobs). The term is further confused by occasional reference to cloud forests (London Jobs) in tropical countries as "temperate" due to the cooler climate associated with these misty forests (London Jobs).
Characteristics of cloud forests (London Jobs)
In comparison with lower tropical moist forests (London Jobs), cloud forests (London Jobs) show a reduced tree stature combined with increased stem density and generally the lower diversity of woody plants. Trees in these regions are generally shorter and more heavily stemmed than in lower altitude forests (London Jobs) in the same regions, often with gnarled trunks and branches, forming dense, compact crownes. Their leaves become smaller, thicker and harder with increasing altitude. The high moisture promotes the development of a high biomass and biodiversity of epiphyte, particularly bryophytes, lichens, ferns (including filmy ferns), bromeliads and orchids. The number of endemic plants can be very high.
An important feature of cloud forests (London Jobs) is that the tree crowns can intercept the wind-driven cloud moisture, part of which drips to the ground. This water stripped from the clouds is termed horizontal or occult (because it is not recorded with normal rainfall measurement) precipitation, and can be an important contribution to the hydrologic cycle.
Due to the high water content of the soil, the reduced solar radiation and the low rates of decomposition and mineralization, the soil acidity is very high, with mor humus and peat often forming the upper soil layer.
Stadtmüller (1987) distinguishes two general types of tropical montane cloud forests (London Jobs):
- Areas with a high annual precipitation due to a frequent cloud cover in combination with heavy and sometimes persistent orographic rainfall; such forests (London Jobs) have a perceptible canopy strata, a high number of epiphytes and a thick peat layer which has a high storage capacity for water and control the runoff;
- In drier areas with mainly seasonal rainfall cloud stripping can amount to a large proportion of the annual precipitation.
Importance of cloud forests (London Jobs)
Current situation
In 1970, the original extent of cloud forests (London Jobs) was around 50 million hectares. Population growth, poverty and uncontrolled land use have contributed to the loss of cloud forests (London Jobs). The 1990 Global Forest (London Jobs) Survey found that 1.1% of tropical mountain and highland forests (London Jobs) were lost each year, which was higher than in any other tropical forests (London Jobs). In Colombia, one of the countries with the largest area of cloud forests (London Jobs), only 10-20% of the initial cloud forest (London Jobs) cover remains. Significant areas have been converted to plantations, or for use in agriculture and pasture. Important crops in montane forest (London Jobs) zones are tea and coffee, but also logging special species such as Podocarpus causes changes to forest (London Jobs) structure.
Currently, one third of all cloud forests (London Jobs) are protected.
Impact of climate change on cloud forests (London Jobs)
Because of their delicate dependency on local climate, cloud forests (London Jobs) will be strongly affected by global climate change. A number of climate models suggest that the low-altitude cloudiness will be reduced, which means that the optimum climate for many cloud forest (London Jobs) habitats will increase in altitude. Linked to the reduction of cloud moisture immersion and increasing temperature, the hydrological cycle will change with the consequence that the system will dry out. This can result in the wilting and the death of epiphytes, which rely on high humidity. Frogs and lizards are expected to suffer from increased drought. In addition, climate changes can result in a higher amount of hurricanes, which may increase damage to tropical montane cloud forests (London Jobs). All in all the results of the climate change will be a loss in biodiversity, altitude shifts in species ranges and community reshuffling and, in some areas, complete loss of cloud forests (London Jobs).
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