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125-630: The South-east Tasmania Important Bird Area encompasses much of the land retaining forest and woodland habitats, suitable for breeding swift parrots and forty-spotted pardalotes , from Orford to Recherche Bay in south-eastern Tasmania , Australia . This large 335,777-hectare (829,720-acre) Important Bird Area (IBA) comprises wet and dry eucalypt forests containing old growth Tasmanian blue gums or black gums , and grassy manna gum woodlands, as well as suburban residential centres and farmland where they retain large flowering, and adjacent hollow -bearing, trees. Key tracts of forest within

250-570: A Latinate word denoting a woodland, may be admitted; in a specific technical sense it is restricted to denoting the species of trees that comprise the woodlands of a region, as in its sense in the subject of silviculture . The resorting to sylva in English indicates more precisely the denotation that the use of forest intends. The first known forests on Earth arose in the Middle Devonian (approximately 390 million years ago ), with

375-464: A combination of measures aimed at increasing forest carbon stocks, andsustainable timber offtake will generate the largest carbon sequestration benefit. The term forest-dependent people is used to describe any of a wide variety of livelihoods that are dependent on access to forests, products harvested from forests, or ecosystem services provided by forests, including those of Indigenous peoples dependent on forests. In India , approximately 22 percent of

500-405: A different classification of forest vegetation is often used: tree, shrub, herb, and moss layers (see stratification (vegetation) ). Forests are classified differently and to different degrees of specificity. One such classification is in terms of the biomes in which they exist, combined with leaf longevity of the dominant species (whether they are evergreen or deciduous ). Another distinction

625-437: A few main pathways, including increase in commercial tree plantations, adoption of agroforestry techniques by small farmers, or spontaneous regeneration when former agricultural land is abandoned. It can be motivated by the economic benefits of forests, the ecosystem services forests provide, or cultural changes where people increasingly appreciate forests for their spiritual, aesthetic, or otherwise intrinsic value. According to

750-412: A fire regime to burn an area equivalent to the total area of an ecosystem is its fire rotation (Heinselman 1973) or fire cycle (Van Wagner 1978). However, as Heinselman (1981) noted, each physiographic site tends to have its own return interval, so that some areas are skipped for long periods, while others might burn two-times or more often during a nominal fire rotation. The dominant fire regime in

875-511: A forest as, "Land spanning more than 0.5 hectares with trees higher than 5 meters and a canopy cover of more than 10 percent, or trees able to reach these thresholds in situ . It does not include land that is predominantly under agricultural or urban use." Using this definition, Global Forest Resources Assessment 2020 found that forests covered 4.06 billion hectares (10.0 billion acres; 40.6 million square kilometres; 15.7 million square miles), or approximately 31 percent of

1000-409: A forest may be of a great variety of species (as in tropical rainforests and temperate deciduous forests ), or relatively few species over large areas (e.g., taiga and arid montane coniferous forests). The biodiversity of forests also encompasses shrubs , herbaceous plants, mosses , ferns , lichens , fungi , and a variety of animals . Trees rising up to 35 meters (115 ft) in height add

1125-550: A forested area by cutting or burning, either to harvest timber or to make way for farming. Most deforestation today occurs in tropical forests. The vast majority of this deforestation is because of the production of four commodities: wood , beef , soy , and palm oil . Over the past 2,000 years, the area of land covered by forest in Europe has been reduced from 80% to 34%. Large areas of forest have also been cleared in China and in

1250-452: A legal term, as seen in Latin texts such as Magna Carta , to denote uncultivated land that was legally designated for hunting by feudal nobility (see royal forest ). These hunting forests did not necessarily contain any trees. Because that often included significant areas of woodland, "forest" eventually came to connote woodland in general, regardless of tree density. By the beginning of

1375-403: A locale with more open space between trees, and distinguish kinds of woodlands as open forests and closed forests , premised on their crown covers . Finally, sylva (plural sylvae or, less classically, sylvas ) is a peculiar English spelling of the Latin silva , denoting a "woodland", and has precedent in English, including its plural forms. While its use as a synonym of forest , and as

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1500-454: A number of adaptations specifically for survival in harsh taiga winters, although larch, which is extremely cold-tolerant, is deciduous . Taiga trees tend to have shallow roots to take advantage of the thin soils, while many of them seasonally alter their biochemistry to make them more resistant to freezing, called "hardening". The narrow conical shape of northern conifers, and their downward-drooping limbs, also help them shed snow. Because

1625-484: A patch of sun; mosses and lichens thrive on the damp ground and on the sides of tree trunks. In comparison with other biomes, however, the taiga has low botanical diversity. Coniferous trees are the dominant plants of the taiga biome. Very few species, in four main genera, are found: the evergreen spruce, fir and pine, and the deciduous larch. In North America, one or two species of fir, and one or two species of spruce, are dominant. Across Scandinavia and western Russia,

1750-560: A polar species, some southern herds of muskoxen reside in the taiga of Russia's Far East and North America. The Amur -Kamchatka region of far eastern Russia also supports the snow sheep , the Russian relative of the American bighorn sheep , wild boar , and long-tailed goral . The largest animal in the taiga is the wood bison of northern Canada/Alaska; additionally, some numbers of the American plains bison have been introduced into

1875-583: A region, releasing water from their leaves in anticipation of seasonal rains to trigger the wet season early. Because of this, seasonal rainfall in the Amazon begins two to three months earlier than the climate would otherwise allow. Deforestation in the Amazon and anthropogenic climate change hold the potential to interfere with this process, causing the forest to pass a threshold where it transitions into savanna. Deforestation threatens many forest ecosystems. Deforestation occurs when humans remove trees from

2000-408: A relatively small variety of highly specialized and adapted animals, due to the harshness of the climate. Canada's boreal forest includes 85 species of mammals , 130 species of fish, and an estimated 32,000 species of insects . Insects play a critical role as pollinators , decomposers , and as a part of the food web. Many nesting birds, rodents, and small carnivorous mammals rely on them for food in

2125-722: A vertical dimension to the area of land that can support plant and animal species, opening up numerous ecological niches for arboreal animal species, epiphytes , and various species that thrive under the regulated microclimate created under the canopy. Forests have intricate three-dimensional structures that increase in complexity with lower levels of disturbance and greater variety of tree species. The biodiversity of forests varies considerably according to factors such as forest type, geography, climate, and soils – in addition to human use. Most forest habitats in temperate regions support relatively few animal and plant species, and species that tend to have large geographical distributions, while

2250-412: A warmer climate. The mature boreal forest pattern in the south shows balsam fir dominant on well-drained sites in eastern Canada changing centrally and westward to a prominence of white spruce , with black spruce and tamarack forming the forests on peats, and with jack pine usually present on dry sites except in the extreme east, where it is absent. The effects of fires are inextricably woven into

2375-412: A wide range of characteristics. Generally, richer households derive more cash value from forest resources, whereas among poorer households, forest resources are more important for home consumption and increase community resilience. Forests are fundamental to the culture and livelihood of indigenous people groups that live in and depend on forests, many of which have been removed from and denied access to

2500-400: Is a stub . You can help Misplaced Pages by expanding it . Forest A forest is an ecosystem characterized by a dense community of trees . Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' Food and Agriculture Organization (FAO) defines

2625-581: Is a threat to taiga, and how the carbon dioxide absorbed or emitted should be treated by carbon accounting is controversial. Taiga covers 17 million square kilometres (6.6 million square miles) or 11.5% of the Earth's land area, second only to deserts and xeric shrublands . The largest areas are located in Russia and Canada. In Sweden taiga is associated with the Norrland terrain . After

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2750-401: Is based on tree densities measured on over 400,000 plots. It remains subject to a wide margin of error, not least because the samples are mainly from Europe and North America. Forests can also be classified according to the amount of human alteration. Old-growth forest contains mainly natural patterns of biodiversity in established seral patterns, and they contain mainly species native to

2875-409: Is found in the smaller areas with oceanic influences; in coastal areas of Scandinavia and Finland, the growing season of the closed boreal forest can be 145–180 days. The shortest growing season is found at the northern taiga–tundra ecotone , where the northern taiga forest no longer can grow and the tundra dominates the landscape when the growing season is down to 50–70 days, and the 24-hr average of

3000-427: Is further evidence pointing to a long and intimate association with fire. Seven of the ten most common trees in the boreal forest— jack pine , lodgepole pine , aspen , balsam poplar ( Populus balsamifera ), paper birch , tamarack , black spruce – can be classed as pioneers in their adaptations for rapid invasion of open areas. White spruce shows some pioneering abilities, too, but is less able than black spruce and

3125-630: Is high compared to other vegetation communities. Much of this biomass occurs below 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. The world's forests contain about 606 gigatonnes of living biomass (above- and below-ground) and 59 gigatonnes of dead wood. The total biomass has decreased slightly since 1990, but biomass per unit area has increased. Forest ecosystems broadly differ based on climate ; latitudes 10° north and south of

3250-554: Is home to many types of berries . Some species are confined to the southern and middle closed-boreal forest (such as wild strawberry and partridgeberry ); others grow in most areas of the taiga (such as cranberry and cloudberry ). Some berries can grow in both the taiga and the lower arctic (southern regions) tundra, such as bilberry , bunchberry and lingonberry . The forests of the taiga are largely coniferous , dominated by larch , spruce , fir and pine . The woodland mix varies according to geography and climate; for example,

3375-412: Is legally protected from resource development. 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 planning or defined management areas, such as certified forests. Boreal forest The principal tree species, depending on the length of the growing season and summer temperatures, vary across

3500-416: Is not a limiting factor, the ground freezes during the winter months and plant roots are unable to absorb water, so desiccation can be a severe problem in late winter for evergreens. Although the taiga is dominated by coniferous forests, some broadleaf trees also occur, including birch , aspen , willow , and rowan . Many smaller herbaceous plants, such as ferns and occasionally ramps grow closer to

3625-543: Is not on track to meet the target of the United Nations Strategic Plan for Forests to increase forest area by 3 percent by 2030. While deforestation is taking place in some areas, new forests are being established through natural expansion or deliberate efforts in other areas. As a result, the net loss of forest area is less than the rate of deforestation; and it, too, is decreasing: from 7.8 million hectares (19 million acres) per year in

3750-564: Is not used consistently by all cultures. In the English language, "boreal forest" is used in the United States and Canada in referring to more southerly regions, while "taiga" is used to describe the more northern, barren areas approaching the tree line and the tundra . Hoffman (1958) discusses the origin of this differential use in North America and how this differentiation distorts established Russian usage. Climate change

3875-428: Is that forests can turn from a carbon sink to a carbon source if plant diversity, density or forest area decreases, as has been observed in different tropical forests The typical tropical forest may become a carbon source by the 2060s. An assessment of European forests found early signs of carbon sink saturation, after decades of increasing strength. The Intergovernmental Panel on Climate Change (IPCC) concluded that

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4000-416: Is whether the forests are composed predominantly of broadleaf trees, coniferous (needle-leaved) trees, or mixed. The number of trees in the world, according to a 2015 estimate, is 3 trillion, of which 1.4 trillion are in the tropics or sub-tropics, 0.6 trillion in the temperate zones, and 0.7 trillion in the coniferous boreal forests. The 2015 estimate is about eight times higher than previous estimates, and

4125-547: The Bering land bridge , a number of animal and plant species , more animals than plants, were able to colonize both land masses, and are globally-distributed throughout the taiga biome (see Circumboreal Region ). Others differ regionally, typically with each genus having several distinct species, each occupying different regions of the taiga. Taigas also have some small-leaved deciduous trees, like birch , alder , willow , and poplar . These grow mostly in areas further south of

4250-485: The Dfd and Dwd climate zones continuous permafrost occurs and restricts growth to very shallow-rooted trees like Siberian larch . The growing season , when the vegetation in the taiga comes alive, is usually slightly longer than the climatic definition of summer as the plants of the boreal biome have a lower temperature threshold to trigger growth than other plants. Some sources claim 130 days growing season as typical for

4375-699: The Eastern Canadian forests ecoregion (of the higher elevations of the Laurentian Mountains and the northern Appalachian Mountains ) in Canada is dominated by balsam fir Abies balsamea , while further north, the Eastern Canadian Shield taiga (of northern Quebec and Labrador ) is mostly black spruce Picea mariana and tamarack larch Larix laricina . Evergreen species in the taiga (spruce, fir, and pine) have

4500-554: The Equator , and temperate forests at the middle latitudes . Forests form in areas of the Earth with high rainfall, while drier conditions produce a transition to savanna . However, in areas with intermediate rainfall levels, forest transitions to savanna rapidly when the percentage of land that is covered by trees drops below 40 to 45 percent. Research conducted in the Amazon rainforest shows that trees can alter rainfall rates across

4625-722: The Holocene epoch, covering land that had been mammoth steppe or under the Scandinavian Ice Sheet in Eurasia and under the Laurentide Ice Sheet in North America during the Late Pleistocene . Although at high elevations taiga grades into alpine tundra through Krummholz , it is not exclusively an alpine biome, and unlike subalpine forest , much of taiga is lowlands. The term "taiga"

4750-498: The Köppen climate classification scheme, meaning that the short summers (24 h average 10 °C (50 °F) or more), although generally warm and humid, only last 1–3 months, while winters, with average temperatures below freezing, last 5–7 months. In Siberian taiga the average temperature of the coldest month is between −6 °C (21 °F) and −50 °C (−58 °F). There are also some much smaller areas grading towards

4875-651: The Medieval Latin foresta , denoting "open wood", Carolingian scribes first used foresta in the capitularies of Charlemagne , specifically to denote the royal hunting grounds of the king. The word was not endemic to the Romance languages , e.g., native words for forest in the Romance languages derived from the Latin silva , which denoted "forest" and " wood(land) " ( cf. the English sylva and sylvan ;

5000-592: The Proto-Germanic * furhísa- , * furhíþija- , denoting "a fir-wood , coniferous forest", from the Proto-Indo-European * perk u- , denoting "a coniferous or mountain forest , wooded height" all attest to the Frankish * forhist . Uses of forest in English to denote any uninhabited and unenclosed area are presently considered archaic. The Norman rulers of England introduced the word as

5125-680: The Scots pine is a common component of the taiga, while taiga of the Russian Far East and Mongolia is dominated by larch . Rich in spruce and Scots pine (in the western Siberian plain), the taiga is dominated by larch in Eastern Siberia, before returning to its original floristic richness on the Pacific shores. Two deciduous trees mingle throughout southern Siberia: birch and Populus tremula . The boreal forest/taiga supports

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5250-554: The Special Report on Global Warming of 1.5 °C of the Intergovernmental Panel on Climate Change , to avoid temperature rise by more than 1.5 degrees above pre-industrial levels, there will need to be an increase in global forest cover equal to the land area of Canada (10 million square kilometres (3.9 million square miles)) by 2050. China instituted a ban on logging, beginning in 1998, due to

5375-592: The World Resources Institute recorded that only 20% of the world's original forests remained in large intact 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. According to Food and Agriculture Organization 's (FAO) Global Forest Resources Assessment 2020 , an estimated 420 million hectares (1.0 billion acres) of forest have been lost worldwide through deforestation since 1990, but

5500-418: The boreal region and in the seasonally dry tropics. At high latitudes, north of the main zone of boreal forestland, growing conditions are not adequate to maintain a continuously closed forest cover , so tree cover is both sparse and discontinuous. This vegetation is variously called open taiga , open lichen woodland, and forest tundra. A savanna is a mixed woodland – grassland ecosystem characterized by

5625-407: The equator are mostly covered in tropical rainforest , and the latitudes between 53°N and 67°N 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. The trees that form the principal structural and defining component of

5750-419: The golden eagle , rough-legged buzzard (also known as the rough-legged hawk), Steller's sea eagle (in coastal northeastern Russia-Japan), great gray owl , snowy owl , barred owl , great horned owl , crow and raven . The only other viable adaptation is seed-eating birds, which include several species of grouse , capercaillie and crossbills . Fire has been one of the most important factors shaping

5875-517: The lowest reliably recorded temperatures in the Northern Hemisphere were recorded in the taiga of northeastern Russia. Taiga has a subarctic climate with very large temperature range between seasons. −20 °C (−4 °F) would be a typical winter day temperature and 18 °C (64 °F) an average summer day, but the long, cold winter is the dominant feature. This climate is classified as Dfc , Dwc , Dsc , Dfd and Dwd in

6000-445: The middle boreal (closed forest), and the southern boreal , a closed-canopy, boreal forest with some scattered temperate, deciduous trees among the conifers. Commonly seen are species such as maple, elm and oak. This southern boreal forest experiences the longest and warmest growing season of the biome. In some regions, including Scandinavia and western Russia, this subzone is commonly used for agricultural purposes. The boreal forest

6125-498: The peatlands . During the last quarter of the twentieth century, the zone of latitude occupied by the boreal forest experienced some of the greatest temperature increases on Earth. Winter temperatures have increased more than summer temperatures. In summer, the daily low temperature has increased more than the daily high temperature. The number of days with extremely cold temperatures (e.g., −20 to −40 °C; −4 to −40 °F) has decreased irregularly but systematically in nearly all

6250-408: The slash and burn practices of swidden agriculture or shifting cultivation . The loss and re-growth of forests lead 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,

6375-429: The 1990s to 4.7 million hectares (12 million acres) per year during 2010–2020. In absolute terms, the global forest area decreased by 178 million hectares (440 million acres; 1,780,000 square kilometres; 690,000 square miles) between 1990 and 2020, which is an area about the size of Libya. Forests provide a diversity of ecosystem services including: The main ecosystem services can be summarized in

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6500-521: The 1990s. In 2015, a study for Nature Climate Change showed that the trend has recently been reversed, leading to an "overall gain" in global biomass and forests. This gain is due especially to reforestation in China and Russia. New forests are not equivalent to old growth forests in terms of species diversity, resilience, and carbon capture. On 7 September 2015, the FAO released a new study stating that over

6625-466: The Cordilleran region, fire is most frequent in the valley bottoms, decreasing upward, as shown by a mosaic of young pioneer pine and broadleaf stands below, and older spruce–fir on the slopes above. Without fire, the boreal forest would become more and more homogeneous, with the long-lived white spruce gradually replacing pine, aspen, balsam poplar, and birch, and perhaps even black spruce, except on

6750-459: The Earth's plant biomass . Net primary production is estimated at 21.9 gigatonnes of biomass per year for tropical forests , 8.1 for temperate forests , and 2.6 for boreal forests . Forests form distinctly different biomes at different latitudes and elevations, and with different precipitation and evapotranspiration rates. These biomes include boreal forests in subarctic climates, tropical moist forests and tropical dry forests around

6875-590: The Hudson Bay area), chum salmon , Siberian taimen , lenok and lake chub . The taiga is mainly home to a number of large herbivorous mammals , such as Alces alces ( moose ), and a few subspecies of Rangifer tarandus ( reindeer in Eurasia; caribou in North America). Some areas of the more southern closed boreal forest have populations of other Cervidae species, such as the maral , elk , Sitka black-tailed deer , and roe deer . While normally

7000-861: The IBA include Wielangta , the Meehan and Wellington Ranges , and the Tasman Peninsula . The area has been identified by BirdLife International as an IBA because it contains almost all the breeding habitat of the endangered swift parrot on the Tasmanian mainland, several populations of the endangered forty-spotted pardalote, as well as good numbers of flame and pink robins , striated fieldwrens and populations of all of Tasmania's endemic bird species. 42°59′35″S 147°25′56″E  /  42.99306°S 147.43222°E  / -42.99306; 147.43222 This Tasmania geography article

7125-725: The Italian, Spanish, and Portuguese selva ; the Romanian silvă ; the Old French selve ). Cognates of forest in Romance languages—e.g., the Italian foresta , Spanish and Portuguese floresta , etc.—are all ultimately derivations of the French word. The precise origin of Medieval Latin foresta is obscure. Some authorities claim the word derives from the Late Latin phrase forestam silvam , denoting "the outer wood"; others claim

7250-441: The Russian far-east, as part of the taiga regeneration project called Pleistocene Park , in addition to Przewalski's horse . Small mammals of the taiga biome include rodent species such as the beaver , squirrel , chipmunk , marmot , lemming , North American porcupine and vole , as well as a small number of lagomorph species, such as the pika , snowshoe hare and mountain hare . These species have adapted to survive

7375-452: The U.S. state of Wisconsin , forests managed by indigenous people have more plant diversity, fewer invasive species, higher tree regeneration rates, and higher volume of trees. Forest management has changed considerably over the last few centuries, with rapid changes from the 1980s onward, culminating in a practice now referred to as sustainable forest management . Forest ecologists concentrate on forest patterns and processes, usually with

7500-460: 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 consultation with local communities and other stakeholders . Humans have generally decreased the amount of forest worldwide. Anthropogenic factors that can affect forests include logging, urban sprawl , human-caused forest fires , acid rain , invasive species , and

7625-420: The basis of the variation of physiognomy corresponding to changes in altitude. Tropical 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 being leafless for several months of the year. Under some conditions, such as less fertile soils or less predictable drought regimes,

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7750-440: The boreal forest is high-intensity crown fires or severe surface fires of very large size, often more than 10,000 ha (100 km ), and sometimes more than 400,000 ha (4000 km ). Such fires kill entire stands. Fire rotations in the drier regions of western Canada and Alaska average 50–100 years, shorter than in the moister climates of eastern Canada, where they may average 200 years or more. Fire cycles also tend to be long near

7875-471: The boreal forest, typically with abrupt, irregular boundaries circumscribing homogenous stands, is indirect but compelling testimony to the role of fire in shaping the forest. The fact is that most boreal forest stands are less than 100 years old, and only in the rather few areas that have escaped burning are there stands of white spruce older than 250 years. The prevalence of fire-adaptive morphologic and reproductive characteristics of many boreal plant species

8000-527: The boreal region, allowing better survival for tree-damaging insects. In Fairbanks, Alaska , the length of the frost-free season has increased from 60 to 90 days in the early twentieth century to about 120 days a century later. It has been hypothesized that the boreal environments have only a few states which are stable in the long term - a treeless tundra/steppe, a forest with >75% tree cover and an open woodland with ~20% and ~45% tree cover. Thus, continued climate change would be able to force at least some of

8125-590: The canopy; but other taxa are also important. In the Southern Hemisphere , most coniferous trees (members of Araucariaceae and Podocarpaceae ) occur mixed with broadleaf species, and are classed as broadleaf-and-mixed forests. Temperate broadleaf and mixed forests include a substantial component of trees of the Anthophyta group. They are generally characteristic of the warmer temperate latitudes, but extend to cool temperate ones, particularly in

8250-423: The children live. Canada has about 4 million square kilometres (1.5 million square miles) 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 include extensive consultation with local stakeholders. About eight percent of Canada's forest

8375-526: The composition and development of boreal forest stands; it is the dominant stand-renewing disturbance through much of the Canadian boreal forest. The fire history that characterizes an ecosystem is its fire regime , which has 3 elements: (1) fire type and intensity (e.g., crown fires, severe surface fires, and light surface fires), (2) size of typical fires of significance, and (3) frequency or return intervals for specific land units. The average time within

8500-517: The cutoff points are between a forest, woodland , and savanna . Under some definitions, to be considered a forest requires very high levels of tree canopy cover, from 60% to 100%, which excludes woodlands and savannas, which have a lower canopy cover . Other definitions consider savannas to be a type of forest, and include all areas with tree canopies over 10%. Some areas covered with trees are legally defined as agricultural areas, for example Norway spruce plantations, under Austrian forest law, when

8625-487: The dark winters, depending on latitude. The areas of the taiga inside the Arctic Circle have midnight sun in mid-summer and polar night in mid-winter. The taiga experiences relatively low precipitation throughout the year (generally 200–750 mm (7.9–29.5 in) annually, 1,000 mm (39 in) in some areas), primarily as rain during the summer months, but also as snow or fog . Snow may remain on

8750-539: The dense vegetation growth including large trees. This explains the striking difference in biomass per square metre between the Taiga and the Steppe biomes, (in warmer climates), where evapotranspiration exceeds precipitation, restricting vegetation to mostly grasses. In general, taiga grows to the south of the 10 °C (50 °F) July isotherm , occasionally as far north as the 9 °C (48 °F) July isotherm, with

8875-418: The density of trees, area of tree canopy cover, or area of the land occupied by the cross-section of tree trunks ( basal area ) meeting a particular threshold. This type of definition depends upon the presence of trees sufficient to meet the threshold, or at least of immature trees that are expected to meet the threshold once they mature. Under land-cover definitions, there is considerable variation on where

9000-459: The ease with which plants can use its nutrients. The relative lack of deciduous trees, which drop huge volumes of leaves annually, and grazing animals, which contribute significant manure, are also factors. The diversity of soil organisms in the boreal forest is high, comparable to the tropical rainforest . Fallen leaves and moss can remain on the forest floor for a long time in the cool, moist climate, which limits their organic contribution to

9125-411: The eastern United States , in which only 0.1% of land was left undisturbed. Almost half of Earth's forest area (49 percent) is relatively intact, while 9 percent is found in fragments with little or no connectivity. Tropical rainforests and boreal coniferous forests are the least fragmented, whereas subtropical dry forests and temperate oceanic forests are among the most fragmented. Roughly 80 percent of

9250-522: The erosion and flooding that it caused. In addition, ambitious tree-planting programmes in countries such as China, India, the United States, and Vietnam – combined with natural expansion of forests in some regions – have added more than 7 million hectares (17 million acres) of new forests annually. As a result, the net loss of forest area was reduced to 5.2 million hectares (13 million acres) per year between 2000 and 2010, down from 8.3 million hectares (21 million acres) annually in

9375-465: The evolution of cladoxylopsid plants like Calamophyton . Appeared in the Late Devonian , Archaeopteris was both tree-like and fern -like plant, growing to 20 metres (66 ft) in height or more. It quickly spread throughout the world, from the equator to subpolar latitudes. It is the first species known to cast shade due to its fronds and forming soil from its roots. Archaeopteris

9500-417: The forest ecosystem. Since 2002, the amount of land that is legally owned by or designated for indigenous peoples has broadly increased, but land acquisition in lower-income countries by multinational corporations, often with little or no consultation of indigenous peoples, has also increased. Research in the Amazon rainforest suggests that indigenous methods of agroforestry form reservoirs of biodiversity. In

9625-459: The forest history of an area 280 km north of the then-current tree line at Ennadai Lake, District Keewatin, Northwest Territories. Two lines of evidence support the thesis that fire has always been an integral factor in the boreal forest: (1) direct, eye-witness accounts and forest-fire statistics, and (2) indirect, circumstantial evidence based on the effects of fire, as well as on persisting indicators. The patchwork mosaic of forest stands in

9750-415: The fourteenth century, English texts used the word in all three of its senses: common, legal, and archaic. Other English words used to denote "an area with a high density of trees" are firth , frith , holt , weald , wold , wood , and woodland . Unlike forest , these are all derived from Old English and were not borrowed from another language. Some present classifications reserve woodland for denoting

9875-404: The ground for as long as nine months in the northernmost extensions of the taiga biome. The fog, especially predominant in low-lying areas during and after the thawing of frozen Arctic seas, stops sunshine from getting through to plants even during the long summer days. As evaporation is consequently low for most of the year, annual precipitation exceeds evaporation, and is sufficient to sustain

10000-519: The ground. Periodic stand-replacing wildfires (with return times of between 20 and 200 years) clear out the tree canopies, allowing sunlight to invigorate new growth on the forest floor. For some species, wildfires are a necessary part of the life cycle in the taiga; some, e.g. jack pine have cones which only open to release their seed after a fire, dispersing their seeds onto the newly cleared ground; certain species of fungi (such as morels ) are also known to do this. Grasses grow wherever they can find

10125-493: The harsh winters in their native ranges. Some larger mammals, such as bears , eat heartily during the summer in order to gain weight, and then go into hibernation during the winter. Other animals have adapted layers of fur or feathers to insulate them from the cold. Predatory mammals of the taiga must be adapted to travel long distances in search of scattered prey, or be able to supplement their diet with vegetation or other forms of food (such as raccoons ). Mammalian predators of

10250-472: The higher latitudes of the Northern Hemisphere , as well as some warm temperate areas, especially 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 , firs Abies , Douglas firs Pseudotsuga , and hemlocks Tsuga make up

10375-486: The interior of the continents, with the driest climates, the boreal forests might grade into temperate grassland . There are two major types of taiga. The southern part is the closed canopy forest , consisting of many closely-spaced trees and mossy groundcover. In clearings in the forest, shrubs and wildflowers are common, such as the fireweed and lupine . The other type is the lichen woodland or sparse taiga , with trees that are farther-spaced and lichen groundcover;

10500-469: The lands on which they lived as part of global colonialism . Indigenous lands contain 36% or more of intact forest worldwide, host more biodiversity, and experience less deforestation. Indigenous activists have argued that degradation of forests and indigenous peoples' marginalization and land dispossession are interconnected. Other concerns among indigenous peoples include lack of Indigenous involvement in forest management and loss of knowledge related for

10625-493: The last 25 years the global deforestation rate has decreased by 50% due to improved management of forests and greater government protection. There is an estimated 726 million hectares (1.79 billion acres) of forest in protected areas worldwide. Of the six major world regions, South America has the highest share of forests in protected areas, at 31 percent. The area of such areas globally has increased by 191 million hectares (470 million acres) since 1990, but

10750-425: The latter is common in the northernmost taiga. In the northernmost taiga, the forest cover is not only more sparse, but often stunted in growth form; moreover, ice-pruned , asymmetric black spruce (in North America) are often seen, with diminished foliage on the windward side. In Canada, Scandinavia and Finland, the boreal forest is usually divided into three subzones: The high boreal (northern boreal/taiga zone),

10875-991: The montane forests of Africa, South America, Southeast Asia, and lowland forests of Australia, coastal Brazil, the Caribbean islands, Central America, and insular Southeast Asia have many species with small geographical distributions. Areas with dense human populations and intense agricultural land use, such as Europe, parts of Bangladesh, China, India, and North America, are less intact in terms of their biodiversity. Northern Africa, southern Australia, coastal Brazil, Madagascar, and South Africa are also identified as areas with striking losses in biodiversity intactness. A forest consists of many components that can be broadly divided into two categories: biotic (living) and abiotic (non-living). The living parts include trees , shrubs , vines , grasses and other herbaceous (non-woody) plants, mosses , algae , fungi , insects , mammals , birds , reptiles , amphibians , and microorganisms living on

11000-403: The most extreme winter weather. The Dahurian larch tolerates the coldest winters of the Northern Hemisphere, in eastern Siberia. The very southernmost parts of the taiga may have trees such as oak , maple , elm and lime scattered among the conifers, and there is usually a gradual transition into a temperate, mixed forest, such as the eastern forest-boreal transition of eastern Canada. In

11125-530: The next table: Some researchers state that forests do not only provide benefits, but can in certain cases also incur costs to humans. Forests may impose an economic burden, diminish the enjoyment of natural areas, reduce the food-producing capacity of grazing land and cultivated land, reduce biodiversity, reduce available water for humans and wildlife, harbour dangerous or destructive wildlife, and act as reservoirs of human and livestock disease. An important consideration regarding carbon sequestration

11250-491: The oceanic Cfc climate with milder winters, whilst the extreme south and (in Eurasia) west of the taiga reaches into humid continental climates ( Dfb , Dwb ) with longer summers. According to some sources, the boreal forest grades into a temperate mixed forest when mean annual temperature reaches about 3 °C (37 °F). Discontinuous permafrost is found in areas with mean annual temperature below freezing, whilst in

11375-406: The patterns of vegetation on the landscape, which in the east favour black spruce, paper birch, and jack pine over balsam fir, and in the west give the advantage to aspen, jack pine, black spruce, and birch over white spruce. Many investigators have reported the ubiquity of charcoal under the forest floor and in the upper soil profile. Charcoal in soils provided Bryson et al. (1965) with clues about

11500-446: The permanent ice caps and tundra , taiga is the terrestrial biome with the lowest annual average temperatures, with mean annual temperature generally varying from −5 to 5 °C (23 to 41 °F). Extreme winter minimums in the northern taiga are typically lower than those of the tundra. There are taiga areas of eastern Siberia and interior Alaska- Yukon where the mean annual temperature reaches down to −10 °C (14 °F), and

11625-471: The pines to disperse seed at all seasons. Only balsam fir and alpine fir seem to be poorly adapted to reproduce after fire, as their cones disintegrate at maturity, leaving no seed in the crowns. The oldest forests in the northwest boreal region, some older than 300 years, are of white spruce occurring as pure stands on moist floodplains . Here, the frequency of fire is much less than on adjacent uplands dominated by pine, black spruce and aspen. In contrast, in

11750-411: The plants and animals and in the soil, connected by mycorrhizal networks . The main layers of all forest types are the forest floor , the understory, and the canopy. The emergent layer, above the canopy, exists in tropical rainforests. Each layer has a different set of plants and animals, depending upon the availability of sunlight, moisture, and food. In botany and countries like Germany and Poland,

11875-512: The population belongs to forest-dependent communities, which live in close proximity to forests and practice agroforestry as a principal part of their livelihood. People of Ghana who rely on timber and bushmeat harvested from forests and Indigenous peoples of the Amazon rainforest are also examples of forest-dependent people. Though forest-dependence by more common definitions is statistically associated with poverty and rural livelihoods, elements of forest-dependence exist in communities with

12000-423: The presently existing taiga forests into one of the two woodland states or even into a treeless steppe - but it could also shift tundra areas into woodland or forest states as they warm and become more suitable for tree growth. In keeping with this hypothesis, several studies published in the early 2010s found that there was already a substantial drought-induced tree loss in the western Canadian boreal forests since

12125-615: The proportion of evergreen species increases and the forests are characterised as " sclerophyllous ". Thorn forest , a dense forest of low stature with a high frequency of thorny or spiny species, is found where drought is prolonged, and especially where grazing animals are plentiful. On very poor soils, and especially where fire or herbivory are recurrent phenomena, savannas develop. Sparse trees and savanna are forests with sparse tree- canopy 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

12250-428: The rate of forest loss has declined substantially. In the most recent five-year period (2015–2020), the annual rate of deforestation was estimated at 10 million hectares (25 million acres), down from 12 million hectares (30 million acres) annually in 2010–2015. The transition of a region from forest loss to net gain in forested land is referred to as the forest transition. This change occurs through

12375-465: The rate of annual increase slowed in 2010–2020. 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

12500-460: The region and habitat. In contrast, secondary forest is forest regrowing following timber harvest and may contain species originally from other regions or habitats. Different global forest classification systems have been proposed, but none has gained universal acceptance. UNEP - WCMC 's forest category classification system is a simplification of other, more complex systems (e.g. UNESCO 's forest and woodland 'subformations'). This system divides

12625-416: The soil. Acids from evergreen needles further leach the soil, creating spodosol , also known as podzol , and the acidic forest floor often has only lichens and some mosses growing on it. In clearings in the forest and in areas with more boreal deciduous trees, there are more herbs and berries growing, and soils are consequently deeper. Since North America and Eurasia were originally connected by

12750-616: The southern hemisphere. They include such forest types as the mixed deciduous forests of the United States and their counterparts in China and Japan; the broadleaf evergreen rainforests of Japan, Chile , and Tasmania ; the sclerophyllous forests of Australia, central Chile, the Mediterranean , and California; and the southern beech Nothofagus forests of Chile and New Zealand. There are many different types of tropical moist forests , with lowland evergreen broad-leaf tropical rainforests : for example várzea and igapó forests and

12875-434: The southern limit more variable. Depending on rainfall, and taiga may be replaced by forest steppe south of the 15 °C (59 °F) July isotherm where rainfall is very low, but more typically extends south to the 18 °C (64 °F) July isotherm, and locally where rainfall is higher, such as in eastern Siberia and adjacent Outer Manchuria , south to the 20 °C (68 °F) July isotherm. In these warmer areas

13000-542: The summer months. The cold winters and short summers make the taiga a challenging biome for reptiles and amphibians , which depend on environmental conditions to regulate their body temperatures. There are only a few species in the boreal forest, including red-sided garter snake , common European adder , blue-spotted salamander , northern two-lined salamander , Siberian salamander , wood frog , northern leopard frog , boreal chorus frog , American toad , and Canadian toad . Most hibernate underground in winter. Fish of

13125-512: The sun is low in the horizon for most of the year, it is difficult for plants to generate energy from photosynthesis . Pine, spruce and fir do not lose their leaves seasonally and are able to photosynthesize with their older leaves in late winter and spring when light is good but temperatures are still too low for new growth to commence. The adaptation of evergreen needles limits the water lost due to transpiration and their dark green color increases their absorption of sunlight. Although precipitation

13250-580: The taiga has higher species diversity, with more warmth-loving species such as Korean pine , Jezo spruce , and Manchurian fir , and merges gradually into mixed temperate forest or, more locally (on the Pacific Ocean coasts of North America and Asia), into coniferous temperate rainforests where oak and hornbeam appear and join the conifers, birch and Populus tremula . The area currently classified as taiga in Europe and North America (except Alaska)

13375-531: The taiga include Canada lynx , Eurasian lynx , stoat , Siberian weasel , least weasel , sable , American marten , North American river otter , European otter , American mink , wolverine , Asian badger , fisher , timber wolf , Mongolian wolf , coyote , red fox , Arctic fox , grizzly bear , American black bear , Asiatic black bear , Ussuri brown bear , polar bear (only small areas of northern taiga), Siberian tiger , and Amur leopard . More than 300 species of birds have their nesting grounds in

13500-401: The taiga must be able to withstand cold water conditions and be able to adapt to life under ice-covered water. Species in the taiga include Alaska blackfish , northern pike , walleye , longnose sucker , white sucker , various species of cisco , lake whitefish , round whitefish , pygmy whitefish , Arctic lamprey , various grayling species, brook trout (including sea-run brook trout in

13625-809: The taiga. In Canada and Scandinavia, the growing season is often estimated by using the period of the year when the 24-hour average temperature is +5 °C (41 °F) or more. For the Taiga Plains in Canada, growing season varies from 80 to 150 days, and in the Taiga Shield from 100 to 140 days. Other sources define growing season by frost-free days. Data for locations in southwest Yukon gives 80–120 frost-free days. The closed canopy boreal forest in Kenozersky National Park near Plesetsk , Arkhangelsk Province , Russia, on average has 108 frost-free days. The longest growing season

13750-408: The taiga. Siberian thrush , white-throated sparrow , and black-throated green warbler migrate to this habitat to take advantage of the long summer days and abundance of insects found around the numerous bogs and lakes. Of the 300 species of birds that summer in the taiga, only 30 stay for the winter. These are either carrion -feeding or large raptors that can take live mammal prey, such as

13875-690: The terra firme forests of the Amazon Basin ; the peat swamp forests ; dipterocarp forests of Southeast Asia ; and the high forests of the Congo Basin . Seasonal tropical forests , perhaps the best description for the colloquial term " jungle ", typically range from the rainforest zone 10 degrees north or south of the equator , to the Tropic of Cancer and Tropic of Capricorn . Forests located on mountains are also included in this category, divided largely into upper and lower montane formations, on

14000-467: The tree line in the subarctic spruce-lichen woodlands. The longest cycles, possibly 300 years, probably occur in the western boreal in floodplain white spruce. Amiro et al. (2001) calculated the mean fire cycle for the period 1980 to 1999 in the Canadian boreal forest (including taiga) at 126 years. Increased fire activity has been predicted for western Canada, but parts of eastern Canada may experience less fire in future because of greater precipitation in

14125-476: The trees are being grown as Christmas trees and are below a certain height. The word forest derives from the Old French forest (also forès ), denoting "forest, vast expanse covered by trees"; forest was first introduced into English as the word denoting wild land set aside for hunting without necessarily having trees on the land. Possibly a borrowing, probably via Frankish or Old High German , of

14250-425: The trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer that consists primarily of grasses. Savannas maintain an open canopy despite a high tree density. Forest plantations are generally intended for the production of timber and pulpwood . Commonly mono-specific, planted with even spacing between

14375-403: The trees, and intensively managed, these forests are generally important as habitat for native biodiversity . Some are managed in ways that enhance their biodiversity protection functions and can provide ecosystem services such as nutrient capital maintenance, watershed and soil structure protection and carbon storage. The annual net loss of forest area has decreased since 1990, but the world

14500-505: The type of vegetation that grows upon the land; an area can be legally designated "forest" even if no trees grow on it. Land-use definitions are based on the primary purpose the land is used for. Under a land-use definition, any area used primarily for harvesting timber, including areas that have been cleared by harvesting, disease, fire, or for the construction of roads and infrastructure, are still defined as forests, even if they contain no trees. Land-cover definitions define forests based upon

14625-404: The warmest month of the year usually is 10 °C (50 °F) or less. High latitudes mean that the sun does not rise far above the horizon, and less solar energy is received than further south. But the high latitude also ensures very long summer days, as the sun stays above the horizon nearly 20 hours each day, or up to 24 hours, with only around 6 hours of daylight, or none, occurring in

14750-626: The word forest is commonly used, there is no universally recognised precise definition, with more than 800 definitions of forest used around the world. Although a forest is usually defined by the presence of trees, under many definitions an area completely lacking trees may still be considered a forest if it grew trees in the past, will grow trees in the future, or was legally designated as a forest regardless of vegetation type. There are three broad categories of definitions of forest in use: administrative, land use , and land cover . Administrative definitions are legal designations, and may not reflect

14875-461: The word is a Latinisation of the Frankish * forhist , denoting "forest, wooded country", and was assimilated to forestam silvam , pursuant to the common practice of Frankish scribes. The Old High German forst denoting "forest"; Middle Low German vorst denoting "forest"; Old English fyrhþ denoting "forest, woodland, game preserve, hunting ground" (English frith ); and Old Norse fýri , denoting " coniferous forest "; all of which derive from

15000-579: The world's forest area is found in patches larger than 1 million hectares (2.5 million acres). The remaining 20 percent is located in more than 34 million patches around the world – the vast majority less than 1,000 hectares (2,500 acres) in size. Human society and forests can affect one another positively or negatively. Forests provide ecosystem services to humans and serve as tourist attractions. Forests can also affect people's health. Human activities, including unsustainable use of forest resources, can negatively affect forest ecosystems. Although

15125-416: The world's 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 mixed, tropical moist, tropical dry, sparse trees and parkland, and forest plantations. Each category is described in a separate section below. Temperate needleleaf forests mostly occupy

15250-420: The world's land area in 2020. Forests are the largest terrestrial ecosystems of Earth by area, and are found around the globe. 45 percent of forest land is in the tropical latitudes . The next largest share of forests are found in subarctic climates , followed by temperate , and subtropical zones. Forests account for 75% of the gross primary production of the Earth's biosphere , and contain 80% of

15375-466: The world. The taiga of North America is mostly spruce; Scandinavian and Finnish taiga consists of a mix of spruce , pines and birch ; Russian taiga has spruces, pines and larches depending on the region; and the Eastern Siberian taiga is a vast larch forest. Taiga in its current form is a relatively recent phenomenon, having only existed for the last 12,000 years since the beginning of

15500-436: Was deciduous , dropping its fronds onto the forest floor, the shade, soil, and forest duff from the dropped fronds creating the early forest. The shed organic matter altered the freshwater environment, slowing its flow and providing food. This promoted freshwater fish. Forests account for 75% of the gross primary productivity of the Earth's biosphere , and contain 80% of the Earth's plant biomass. Biomass per unit area

15625-407: Was recently glaciated . As the glaciers receded they left depressions in the topography that have since filled with water, creating lakes and bogs (especially muskeg soil) found throughout the taiga. Taiga soil tends to be young and poor in nutrients, lacking the deep, organically enriched profile present in temperate deciduous forests. The colder climate hinders development of soil, and

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