Threats To Forests. A conifer forest in the Swiss Alps Essay Example for Free

Threats To Forests. A conifer woodland in the Swiss Alps EssayMixed broad-leafed plant in Stara Planina, SerbiaA wood, likewise referred to as a wood or the woods, is an commonswealth with a high density of trees. As with cities, depending on various cultural definitions, what is considered a timber may vary squarely in size and gravel variant classifications according to how and what of the quality is imperturbable. These plant communities secrecy approximately 9.4 sh atomic number 18 of the Earths surface (or 30 percent of get land sector), though they once covered much to a greater extent (about 50 percent of total land argona), in numerous different regions and function as habitats for organisms, hydrologic devolve modulators, and soil conservers, constituting one of the nigh of the essence(p) aspects of the biosphere. Although timbers are classified primarily by trees, the concept of a quality ecosystem includes additional species (such as smaller p lants, fungi, bacteria, and animals) as well as physical and chemical processes such as energy flow and alimental cycling.A typical wood is still of the overstory ( disregardopy or upper tree layer) and the understory. The understory is further subdivided into the crotch hair layer, herb layer, and in any case the moss layer and soil microbes. In few hard woodlands, there is as well a well-defined lower tree layer. Forests are central to all human life because they provide a diverse range of resources they store carbon, aid in regulating the planetary climate, purify water and alleviate natural hazards such as floods. Forests also run roughly 90 percent of the worlds terrestrial biodiversity. circumscribe * 1 Etymology * 2 Distri entirelyion * 3 Classification * 3.1 TemperateA typical woods is composed of the overstory (canopy or upper tree layer) and the understory. The understory is further subdivided into the shrub layer, herb layer, and also the moss layer and soil microbes. In some complex woodlands, there is also a well-defined lower tree layer. Forests are central to all human life because they provide a diverse range of resources they store carbon, aid in regulating the planetary climate, purify water and mitigate natural hazards such as floods. Forests also contain roughly 90 percent of the worlds terrestrial biodiversity.EtymologyThe countersignature tone comes from Middle English forest, from Old french forest (also fors) forest, vast expanse covered by trees first introduced in English as the term for wild land set aside for hunting without the necessity in definition for the existence of trees (James 1981Muir 2000,2008). mayhap a borrowing (probably via Frankish or Old High German) of the Medieval Latin word foresta pass on wood, foresta was first used by Carolingian scribes in the Capitularies of Charlemagne to refer specifically to the kings royal hunting institutes. The line was non endemic to Romance languages (e.g. native words for forest in the Romance languages evolved out of the Latin word silva forest, wood (English sylvan) cf. Italian, Spanish, Portuguese selva Romanian silv Old French selve) and cognates in Romance languages, such as Italian foresta, Spanish and Portuguese floresta, etcetera are all at last borrowings of the French word. The exact origin of Medieval Latin foresta is obscure. Some authorities claim the word derives from the latterly Latin phrase forestam silvam, meaning the outer wood former(a)(a)s claim the term is a latinisation of the Frankish word *forhist forest, wooded country, assimilated to forestam silvam (a common practise among Frankish scribes). Frankish *forhist is attested by Old High German forst forest, Middle Low German vorst forest, Old English fyrh forest, woodland, game preserve, hunting ground, and Old Norse fri coniferous forest, all of which derive from Proto-Germanic *fursa-, *furja- a fir-wood, coniferous forest, from Proto-Indo-European *perkwu- a coniferous or mountain forest, wooded h eighter. Uses of the word forest in English to denote any uninhabited area of non-enclosure are now considered archaic. The word was introduced by the Norman rulers of England as a legal term (appearing in Latin texts like the Magna Carta) denoting an uncultivated area legally set aside for hunting by feudalistic nobility (see Royal Forest). These hunting forests were not necessarily wooded much, if at all. However, as hunting forests did oftentimes include considerable areas of woodland, the word forest eventually came to mean wooded land more chiefly. By the start of the fourteenth century the word appeared inEnglish texts, indicating all three senses the most common one, the legal term and the archaic usage. Forest near Rajgir, Bihar, IndiaOther hurt used to mean an area with a high density of trees are wood, woodland, wold, weald, holt, frith and firth. Unlike forest, these are all derived from Old English and were not borrowed from an other language. Some classifications now reserve the term woodland for an area with more centripetal musculus quadriceps femoris amidst trees and distinguish among woodlands, open forests, and closed forests tie-upd on crown cover. DistributionAmazon pelting forest in BrazilTemperate rainforest in Tasmanias Hellyer GorgeForests can be found in all regions capable of sustaining tree growth, at altitudes up to the tree line, except where natural fire frequence or other disturbance is too high, or where the environment has been altered by human activity. The latitudes 10 north and south of the Equator are mostly covered in tropical rainforest, and the latitudes amidst 53N and 67N have boreal forest. As a general rule, forests dominated by angiosperms (broadleaf forests) are more species-rich than those dominated by gymnosperms (conifer, montane, or needleleaf forests), although exceptions exist. Forests sometimes contain some tree species only at bottom a small area (as in tr opical rain and temperate broad-leaved forests), or comparatively fewer species over large areas (e.g., taiga and arid montane coniferous forests). Forests are often home to many a(prenominal) animal and plant species, and biomass per unit area is high compared to other vegetation communities. a lot of this biomass sinks at a lower place ground in the root systems and as partially decomposed plant detritus. The woody component of a forest contains lignin, which is relatively slow to decompose compared with other organic materials such as cellulose or carbohydrate. Forests are differentiated from woodlands by the extent of canopy coverage in a forest, the branches and the foliage of separate trees often meet or interlock, although there can be gaps of varying sizes inwardly an area referred to as forest. A woodland has a more day-and-nightly open canopy, with trees spaced farther apart, which allows more sunlight to penetrate to the ground between them (also see savanna). Am ong the major forested biomes are* rain forest (tropical and temperate)* taiga* temperate hardwood forest* tropical juice slight forestClassificationBiogradska forest in MontenegroSpiny forest at Ifaty, Madagascar, featuring various Adansonia (baobab) species, Alluaudia procera (Madagascar ocotillo) and other vegetationEven, dense old-growth stand of beech trees (Fagus sylvatica) prepared to be regenerated by their saplings in the understory, in the capital of Belgium part of the Sonian Forest.Trees on a mountain in northern Utah during early autumn.Forests can be classified in different ways and to different degrees of specificity. One such way is in terms of the biome in which they exist, combined with leaf longevity of the dominant species (whether they are semi-evergreen or deciduous). Another banknote is whether the forests are composed predominantly of broadleaf trees, coniferous (needle-leaved) trees, or fuse. * Boreal forests occupy the subarctic regularise and are gene rally evergreen and coniferous. * Temperate partitions support both broadleaf deciduous forests (e.g., temperate deciduous forest) and evergreen coniferous forests (e.g., temperate coniferous forests and temperate rainforests).Warm temperate zones support broadleaf evergreen forests, including laurel forests. * Tropical and subtropical forests include tropical and subtropical wet forests, tropical and subtropical dry forests, and tropical and subtropical coniferous forests. * Physiognomy classifies forests based on their overall physical structure or findmental stage (e.g. old growth vs. second growth). * Forests can also be classified more specifically based on the climate and the dominant tree species present, resulting in numerous different forest types (e.g., ponderosa pine/Douglas-fir forest). A number of globose forest classification systems have been proposed, but none has gained universal acceptance. UNEP-WCMCs forest category classification system is a simplification of other more complex systems (e.g. UNESCOs forest and woodland subformations). This system divides the worlds forests into 26 major types, which reflect climatic zones as well as the principal types of trees. These 26 major types can be reclassified into 6 broader categories temperate needleleaf temperate broadleaf and manifold tropical moist tropical dry sparse trees and parkland and forest groves. Each category is draw as a separate section below. Temperate needleleafTemperate needleleaf forests mostly occupy the higher latitude regions of the northern hemisphere, as well as high altitude zones and some warm temperate areas, oddly on nutrient-poor or otherwise unfavourable soils. These forests are composed entirely, or nearly so, of coniferous species (Coniferophyta). In the Northern Hemisphere pines Pinus, spruces Picea, larches Larix, silver firs Abies, Douglas firs Pseudotsuga and hemlocks Tsuga, make up the canopy, but other taxa are also important. In the Southern Hemisphe re, most coniferous trees (members of the Araucariaceae and Podocarpaceae) occur in concoctions with broadleaf species that are classed as broadleaf and mixed forests. Temperate broadleaf and mixedTemperate broadleaf and mixed forests include a substantial component of trees in the Anthophyta. They are generally characteristic of the warmer temperate latitudes, but exceed to cool temperate ones, particularly in the Confederate hemisphere. They include such forest types as the mixed deciduous forests of the United States and their counterparts in mainland China and Japan, the broadleaf evergreen rainforests of Japan, Chile and Tasmania, the sclerophyllous forests of Australia, central Chile, the Mediterranean and atomic number 20, and the southern beech Nothofagus forests of Chile and New Zealand. Tropical moistThere are many different types of tropical moist forests,although most extensive are the lowland evergreen broadleaf rainforests, for example vrzea and igap forests and th e terra firma forests of the Amazon Basin the peat sop forests, dipterocarp forests of Southeast Asia and the high forests of the Congo Basin. Forests located on mountains are also included in this category, divided largely into upper and lower montane formations on the basis of the pas seul of physiognomy corresponding to changes in altitude. Tropical dryTropical dry forests are characteristic of areas in the tropics affected by seasonal drought. The seasonality of rainfall is usually reflected in the deciduousness of the forest canopy, with most trees world leafless for several months of the year. However, under some conditions, e.g. less fertile soils or less predictable drought regimes, the proportion of evergreen species increases and the forests are characterised as sclerophyllous. Thorn forest, a dense forest of low peak with a high relative frequency of thorny or spiny species, is found where drought is prolonged, and especially where skimming animals are plentiful. O n very poor soils, and especially where fire is a recurrent phenomenon, woody savannas develop (see sparse trees and parkland). tenuous trees and parklandTaiga forest near Saranpaul in the northeast Ural Mountains, KhantyMansia, Russia. Trees include Picea obovata (dominant on right bank), Larix sibirica, Pinus sibirica, and Betula pendula. Sparse trees and parkland are forests with open canopies of 10-30% crown cover. They occur principally in areas of transition from forested to non-forested landscapes. The two major zones in which these ecosystems occur are in the boreal region and in the seasonally dry tropics. At high latitudes, north of the main zone of boreal forest or taiga, growing conditions are not adequate to maintain a continuous closed forest cover, so tree cover is both sparse and discontinuous. This vegetation is variously called open taiga, open lichen woodland, and forest tundra. It is species-poor, has high bryophyte cover, and is frequently affected by fire. For est plantationsForest plantations, generally intended for the production of timber and pulpwood increase the total area of forest worldwide. Commonly mono-specific and/or composed of introduced tree species, these ecosystems are not generally important as habitat for native biodiversity. However, they can be managed in ways that enhance their biodiversity protection functions and they are important providers of ecosystem services such as maintaining nutrient capital, protecting watersheds and soil structure as well as storing carbon. They may also play an important role in alleviating pressure on natural forests for timber and fuelwood production. Forest categoriesA temperate deciduous broadleaf forest, the Hasenholz, southeast of Kirchheim unter Teck, Baden-Wrttemberg, Germany redwoods in old growth forest in Muir Woods National Monument, Marin County, California 28 forest categories are used to enable the translation of forest types from national and regional classification syste ms to a harmonised global one.Temperate and boreal forest types1. Evergreen needleleaf forest inhering forest with 30% canopy cover, in which the canopy is predominantly ( 75%) needleleaf and evergreen.2. Deciduous needleleaf forests Natural forests with 30% canopy cover, in which the canopy is predominantly ( 75%) needleleaf and deciduous.3. Mixed broadleaf/needleleaf forest Natural forest with 30% canopy cover, in which the canopy is composed of a more or less even mixture of needleleaf and broadleaf crowns (between 5050% and 2575%).4. Broadleaf evergreen forest Natural forests with 30% canopy cover, the canopy being 75% evergreen and broadleaf.5. Deciduous broadleaf forest Natural forests with 30% canopy cover, in which 75% of the canopy is deciduous and broadleaves prevailing ( 75% of canopy cover).6. freshwater swamp forest Natural forests with 30% canopy cover, composed of trees with any mixture of leaf type and seasonality, but in which the predominant enviro nmental characteristic is a waterlogged soil.7. Sclerophyllous dry forest Natural forest with 30% canopy cover, in which the canopy is generally composed of sclerophyllous broadleaves and is 75% evergreen.8. Disturbed natural forest Any forest type above that has in its interior significant areas of disturbance by people, including clearing, felling for wood extraction, anthropogenic fires, road construction, etc.9. Sparse trees and parkland Natural forests in which the tree canopy cover is between 10-30%, such as in the steppe regions of the world. Trees of any type (e.g., needleleaf, broadleaf,palms).10. Exotic species plantation Intensively managed forests with 30% canopy cover, which have been position by people with species not naturally occurring in that country.11. Native species plantation Intensively managed forests with 30% canopy cover, which have been planted by people with species that occur naturally in that country.12. *Unspecified forest plantation Forest plantations exhibit extent only with no further randomness about their type, This data currently only refers to the Ukraine.13. *Unclassified forest data Forest data showing forest extent only with no further information about their type. Those marked * have been created as a result of data holdings which do not specify the forest type, hence 26 categories are quoted, not 28 shown here. Tropical forest typesThe Fatu Hiva rainforest in Polynesia.1. Lowland evergreen broadleaf rain forest Natural forests with 30% canopy cover, below 1,200 m (3,937 ft) altitude that display little or no seasonality, the canopy being 75% evergreen broadleaf.2. Lower montane forest Natural forests with 30% canopy cover, between 12001800 m altitude, with any seasonality regime and leaf type mixture.3. Upper montane forest Natural forests with 30% canopy cover, above 1,800 m (5,906 ft) altitude, with any seasonality regime and leaf type mixture.4. Freshwater swamp forest Natural forests with 30% canopy cover, below 1,200 m (3,937 ft) altitude, composed of trees with any mixture of leaf type and seasonality, but in which the predominant environmental characteristic is a waterlogged soil.5. Semi-evergreen moist broadleaf forest Natural forests with 30% canopy cover, below 1,200 m (3,937 ft) altitude in which between 50-75% of the canopy is evergreen, 75% are broadleaves, and the trees display seasonality of flowering and fruiting.6. Mixed broadleaf/needleleaf forest Natural forests with 30% canopy cover, below 1,200 m (3,937 ft) altitude, in which the canopy is composed of a more or less even mixture of needleleaf and broadleaf crowns (between 5050% and 2575%).7. Needleleaf forest Natural forest with 30% canopy cover, below 1,200 m (3,937 ft) altitude, in which the canopy is predominantly ( 75%) needleleaf.8. Mangroves Natural forests with 30% canopy cover, composed of speciesof mangrove tree, generally along coasts in or near brackish or seawater.9. Disturbed natur al forest Any forest type above that has in its interior significant areas of disturbance by people, including clearing, felling for wood extraction, anthropogenic fires, road construction, etc.10. Deciduous/semi-deciduous broadleaf forest Natural forests with 30% canopy cover, below 1,200 m (3,937 ft) altitude in which between 50-100% of the canopy is deciduous and broadleaves predominate ( 75% of canopy cover).11. Sclerophyllous dry forest Natural forests with 30% canopy cover, below 1,200 m (3,937 ft) altitude, in which the canopy is mainly composed of sclerophyllous broadleaves and is 75% evergreen.12. Thorn forest Natural forests with 30% canopy cover, below 1,200 m (3,937 ft) altitude, in which the canopy is mainly composed of deciduous trees with thorns and succulent phanerophytes with thorns may be frequent.13. Sparse trees and parkland Natural forests in which the tree canopy cover is between 10-30%, such as in the savannah regions of the world. Trees of any type ( e.g., needleleaf, broadleaf, palms).14. Exotic species plantation Intensively managed forests with 30% canopy cover, which have been planted by people with species not naturally occurring in that country.15. Native species plantation Intensively managed forests with 30% canopy cover, which have been planted by people with species that occur naturally in that country. Forest loss and wayMain articles Forestry, Logging and DeforestationCoastal Douglas fir woodland in northwest OregonRedwood tree in northern California redwood forest, where many redwood trees are managed for preservation and longevity, sort of than being harvested for wood production The scientific study of forest species and their interaction with the environment is referred to as forest ecology, while the management of forests is often referred to as forestry. Forest management has changed considerably over the last few centuries, with rapid changes from the 1980s onwards culminating in a practice now referred to as sustainable forest management.Forest ecologists concentrate on forest patterns and processes, usually with the aim of elucidating cause and effect relationships. Foresters who practice sustainable forest management focus on the integration of ecological, social and economic values, often in citation with local communities and other stakeholders. Anthropogenic factors that can affect forests include logging, urban sprawl, human-caused forest fires, acid rain, invasive species, and the slash and burn practices of swidden agriculture or shifting cultivation. The loss and re-growth of forest leads to a distinction between two broad types of forest, primary or old-growth forest and secondary forest. There are also many natural factors that can cause changes in forests over time including forest fires, insects, diseases, weather, competition between species, etc.In 1997, the World Resources Institute recorded that only 20% of the worlds original forests remained in large inbuilt tracts of undisturbed forest. More than 75% of these intact forests lie in three countries the Boreal forests of Russia and Canada and the rainforest of Brazil. In 2006 this information on intact forests was updated using latest available satellite imagery. Canada has about 4,020,000 square kilometres (1,550,000 sq mi) of forest land. More than 90% of forest land is publicly owned and about 50% of the total forest area is allocated for harvesting. These allocated areas are managed using the principles of sustainable forest management, which includes extensive consultation with local stakeholders. About eight percent of Canadas forest is legally protected from resource development (Global Forest Watch Canada)(Natural Resources Canada).Much more forest land about 40 percent of the total forest land base is subject to varying degrees of protection through processes such as integrated land use be after or defined management areas such as certified forests (Natural Resources Canada) . These single-valued functions represent only virgin forest lost. Some regrowth has occurred but not to the age, size or extent of 1620 due to population increases and food cultivation. From William B. Greeleys, The proportion of Geography to Timber Supply, Economic Geography, 1925, vol. 1, p. 1-11. Source of Today map compiled by George Draffan from roadless area map in The Big Outside A Descriptive Inventory of the Big Wilderness Areas of the United States, by Dave Foreman and Howie Wolke (Harmony Books, 1992). By December 2006, over 1,237,000 square kilometers of forest land in Canada (about half(prenominal) the global total) had been certified as being sustainably managed (Canadian Sustainable Forestry Certification Coalition). Clear stabbing, first used in the latter half of the 20th century, is less expensive, but devastating to the environment and companies are required by law to run across that harvested areas are adequately regenerated. Most Canadian provinces have reg ulations limiting the size of clearcuts, although some older clearcuts can range upwards of 110 square kilometres (27,000 acres) in size which were cut over several years. China instituted a ban on logging, beginning in 1998, due to the destruction caused by clearcutting. Selective cutting avoids the erosion, and flooding, that result from clearcutting. In the United States, most forests have historically been affected by humans to some degree, though in recent years improved forestry practices has helped regulate or moderate large scale leaf or severe impacts.However, the United States Forest Service estimates a net loss of about 2 million hectares (4,942,000 acres) between 1997 and 2020 this estimate includes conversion of forest land to other uses, including urban and suburban development, as well as afforestation and natural reversion of abandoned crop and pasture land to forest. However, in many areas of the United States, the area of forest is stable or increasing, particular ly in many northern states. The diametrical problem from flooding has plagued national forests, with loggers complaining that a lack of thinning and proper forest management has resulted in large forest fires. Old-growth forest contains mainly natural patterns of biodiversity in established seral patterns, and they contain mainly species native to the region and habitat.The natural formations and processes have not been affected by humans with a frequency or intensity to change the natural structure and components of the habitat. Secondary forest contains significant elements of species which were originally from other regions or habitats. Smaller areas of woodland in cities may be managed as Urban forestry, sometimes within public parks. These are often created for human benefits Attention Restoration Theory argues that spending time in nature reduces stress and improves health, while forest schools and kindergartens help young people to develop social as well as scientific skills in forests. These typically need to be close to where the children live, for practical logistics.