Taiga (; rus, тайга́, p=tɐjˈɡa; relates to Mongolic and Turkic languages), generally referred to in
North America
North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...
as a boreal forest or snow forest, is a
biome
A biome () is a biogeographical unit consisting of a biological community that has formed in response to the physical environment in which they are found and a shared regional climate. Biomes may span more than one continent. Biome is a broader ...
forest
A forest is an area of land dominated by 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' ...
s consisting mostly of
pine
A pine is any conifer tree or shrub in the genus ''Pinus'' () of the family Pinaceae. ''Pinus'' is the sole genus in the subfamily Pinoideae. The World Flora Online created by the Royal Botanic Gardens, Kew and Missouri Botanical Garden accep ...
s,
spruce
A spruce is a tree of the genus ''Picea'' (), a genus of about 35 species of coniferous evergreen trees in the family Pinaceae, found in the northern temperate and boreal (taiga) regions of the Earth. ''Picea'' is the sole genus in the subfami ...
s, and
larch
Larches are deciduous conifers in the genus ''Larix'', of the family Pinaceae (subfamily Laricoideae). Growing from tall, they are native to much of the cooler temperate northern hemisphere, on lowlands in the north and high on mountains furt ...
es.
The taiga or boreal forest has been called the world's largest land
biome
A biome () is a biogeographical unit consisting of a biological community that has formed in response to the physical environment in which they are found and a shared regional climate. Biomes may span more than one continent. Biome is a broader ...
. In North America, it covers most of inland
Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...
,
Alaska
Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S., ...
, and parts of the northern contiguous United States. In
Eurasia
Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelago a ...
, it covers most of
Sweden
Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is the Kingdom of SwedenUNGEGN World Geographical Names, Sweden./ref> is a Nordic country located on ...
,
Finland
Finland ( fi, Suomi ; sv, Finland ), officially the Republic of Finland (; ), is a Nordic country in Northern Europe. It shares land borders with Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of B ...
, much of
Russia
Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...
Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...
(including much of
Siberia
Siberia ( ; rus, Сибирь, r=Sibir', p=sʲɪˈbʲirʲ, a=Ru-Сибирь.ogg) is an extensive geographical region, constituting all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has been a part of ...
), much of
Norway
Norway, officially the Kingdom of Norway, is a Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of Jan Mayen and t ...
and
Estonia
Estonia, formally the Republic of Estonia, is a country by the Baltic Sea in Northern Europe. It is bordered to the north by the Gulf of Finland across from Finland, to the west by the sea across from Sweden, to the south by Latvia, a ...
, some of the
Scottish Highlands
The Highlands ( sco, the Hielands; gd, a’ Ghàidhealtachd , 'the place of the Gaels') is a historical region of Scotland. Culturally, the Highlands and the Lowlands diverged from the Late Middle Ages into the modern period, when Lowland Sco ...
, some lowland/coastal areas of
Iceland
Iceland ( is, Ísland; ) is a Nordic island country in the North Atlantic Ocean and in the Arctic Ocean. Iceland is the most sparsely populated country in Europe. Iceland's capital and largest city is Reykjavík, which (along with its s ...
, and areas of northern
Kazakhstan
Kazakhstan, officially the Republic of Kazakhstan, is a transcontinental country located mainly in Central Asia and partly in Eastern Europe. It borders Russia to the north and west, China to the east, Kyrgyzstan to the southeast, Uzbeki ...
, northern
Mongolia
Mongolia; Mongolian script: , , ; lit. "Mongol Nation" or "State of Mongolia" () is a landlocked country in East Asia, bordered by Russia to the north and China to the south. It covers an area of , with a population of just 3.3 million, ...
, and northern
Japan
Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...
(on the island of
Hokkaidō
is Japan's second largest island and comprises the largest and northernmost prefecture, making up its own region. The Tsugaru Strait separates Hokkaidō from Honshu; the two islands are connected by the undersea railway Seikan Tunnel.
The la ...
).
The main tree species, depending on the length of the growing season and summer temperatures, vary across the world. The taiga of North America is mostly spruce,
Scandinavia
Scandinavia; Sámi languages: /. ( ) is a subregion#Europe, subregion in Northern Europe, with strong historical, cultural, and linguistic ties between its constituent peoples. In English usage, ''Scandinavia'' most commonly refers to Denmark, ...
n and
Finnish
Finnish may refer to:
* Something or someone from, or related to Finland
* Culture of Finland
* Finnish people or Finns, the primary ethnic group in Finland
* Finnish language, the national language of the Finnish people
* Finnish cuisine
See also ...
taiga consists of a mix of
spruce
A spruce is a tree of the genus ''Picea'' (), a genus of about 35 species of coniferous evergreen trees in the family Pinaceae, found in the northern temperate and boreal (taiga) regions of the Earth. ''Picea'' is the sole genus in the subfami ...
, pines and
birch
A birch is a thin-leaved deciduous hardwood tree of the genus ''Betula'' (), in the family Betulaceae, which also includes alders, hazels, and hornbeams. It is closely related to the beech-oak family Fagaceae. The genus ''Betula'' contains 30 ...
, Russian taiga has spruces, pines and larches depending on the region, while 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 the
Holocene
The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene togethe ...
epoch, covering land that had been
mammoth steppe
During the Last Glacial Maximum, the mammoth steppe, also known as steppe-tundra, was the Earth's most extensive biome. It spanned from Spain eastward across Eurasia to Canada and from the List of islands in the Arctic Ocean, arctic islands sout ...
Laurentide Ice Sheet
The Laurentide Ice Sheet was a massive sheet of ice that covered millions of square miles, including most of Canada and a large portion of the Northern United States, multiple times during the Quaternary glacial epochs, from 2.58 million years a ...
in North America during the
Late Pleistocene
The Late Pleistocene is an unofficial Age (geology), age in the international geologic timescale in chronostratigraphy, also known as Upper Pleistocene from a Stratigraphy, stratigraphic perspective. It is intended to be the fourth division of ...
.
Although at high elevations taiga grades into
alpine tundra
Alpine tundra is a type of natural region or biome that does not contain trees because it is at high elevation, with an associated alpine climate, harsh climate. As the latitude of a location approaches the poles, the threshold elevation for alp ...
through
Krummholz
''Krummholz'' (german: krumm, "crooked, bent, twisted" and ''Holz'', "wood") — also called ''knieholz'' ("knee timber") — is a type of stunted, deformed vegetation encountered in the subarctic and subalpine
Montane ecosystems are fou ...
, it is not exclusively an alpine biome, and unlike
subalpine forest
Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures fall as elevation increases, causing the ecosystem to stratify. This stratification is a crucial f ...
, much of taiga is lowlands.
The term "taiga" is not used consistently by all cultures. In the English language, "boreal forest" is used in the United States and
Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...
in referring to more southerly regions, while "taiga" is used to describe the more northern, barren areas approaching the
tree line
The tree line is the edge of the habitat at which trees are capable of growing. It is found at high elevations and high latitudes. Beyond the tree line, trees cannot tolerate the environmental conditions (usually cold temperatures, extreme snowp ...
and the
tundra
In physical geography, tundra () is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. The term ''tundra'' comes through Russian (') from the Kildin Sámi word (') meaning "uplands", "treeless moun ...
. Hoffman (1958) discusses the origin of this differential use in North America and how this differentiation distorts established Russian usage.
Climate change
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to E ...
carbon accounting
Greenhouse gas accounting or Carbon accounting is a framework of methods to measure and track how much greenhouse gas (GHG) an organization emits or takes actions to reduce. Corporations, cities and other groups use these techniques to help limi ...
is controversial.
Climate and geography
Taiga covers or 11.5% of the Earth's land area, second only to
deserts and xeric shrublands
Deserts and xeric shrublands are a biome defined by the World Wide Fund for Nature. Deserts and xeric (ancient Greek xērós, “dry") shrublands form the largest terrestrial biome, covering 19% of Earth's land surface area. Ecoregions in this ...
. The largest areas are located in Russia and Canada. In
Sweden
Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is the Kingdom of SwedenUNGEGN World Geographical Names, Sweden./ref> is a Nordic country located on ...
taiga is associated with the
Norrland terrain
Norrland terrain ( sv, link=no, Norrlandsterräng) is a geomorphic unit covering the bulk of Norrland and the northwestern half of Svealand. Except for The High Coast the coastal areas of Norrland do not belong to the Norrland terrain. The sou ...
.
Temperature
After the permanent ice caps and
tundra
In physical geography, tundra () is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. The term ''tundra'' comes through Russian (') from the Kildin Sámi word (') meaning "uplands", "treeless moun ...
, taiga is the terrestrial
biome
A biome () is a biogeographical unit consisting of a biological community that has formed in response to the physical environment in which they are found and a shared regional climate. Biomes may span more than one continent. Biome is a broader ...
with the lowest annual average temperatures, with mean annual temperature generally varying from . 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
Yukon (; ; formerly called Yukon Territory and also referred to as the Yukon) is the smallest and westernmost of Canada's three territories. It also is the second-least populated province or territory in Canada, with a population of 43,964 as ...
Northern Hemisphere
The Northern Hemisphere is the half of Earth that is north of the Equator. For other planets in the Solar System, north is defined as being in the same celestial hemisphere relative to the invariable plane of the solar system as Earth's Nort ...
were recorded in the taiga of northeastern Russia.
Taiga has a
subarctic climate
The subarctic climate (also called subpolar climate, or boreal climate) is a climate with long, cold (often very cold) winters, and short, warm to cool summers. It is found on large landmasses, often away from the moderating effects of an ocean, ge ...
with very large temperature range between seasons. would be a typical winter day temperature and 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 the
Köppen climate classification
The Köppen climate classification is one of the most widely used climate classification systems. It was first published by German-Russian climatologist Wladimir Köppen (1846–1940) in 1884, with several later modifications by Köppen, notabl ...
scheme, meaning that the short summers (24 h average or more), although generally warm and humid, only last 1–4 months, while winters, with average temperatures below freezing, last 5–7 months.
In Siberian taiga the average temperature of the coldest month is between and .''Encyclopedia Universalis'' édition 1976 Vol. 2 ASIE – Géographie physique, p. 568 There are also some much smaller areas grading towards the oceanic ''Cfc'' climate with milder winters, whilst the extreme south and (in Eurasia) west of the taiga reaches into
humid continental climate
A humid continental climate is a climatic region defined by Russo-German climatologist Wladimir Köppen in 1900, typified by four distinct seasons and large seasonal temperature differences, with warm to hot (and often humid) summers and freezing ...
s (''Dfb'', ''Dwb'') with longer summers.
According to some sources, the boreal forest grades into a temperate mixed forest when mean annual temperature reaches about .
Discontinuous permafrost
Permafrost is ground that continuously remains below 0 °C (32 °F) for two or more years, located on land or under the ocean. Most common in the Northern Hemisphere, around 15% of the Northern Hemisphere or 11% of the global surface ...
is found in areas with mean annual temperature below freezing, whilst in the ''Dfd'' and ''Dwd'' climate zones
continuous permafrost
Permafrost is ground that continuously remains below 0 °C (32 °F) for two or more years, located on land or under the ocean. Most common in the Northern Hemisphere, around 15% of the Northern Hemisphere or 11% of the global surface ...
occurs and restricts growth to very shallow-rooted trees like
Siberian larch
''Larix sibirica'', the Siberian larch or Russian larch, is a frost-hardy tree native to western Russia, from close to the Finnish border east to the Yenisei valley in central Siberia, where it hybridises with the Dahurian larch ''L. gmelinii' ...
.
Growing season
The
growing season
A season is a division of the year marked by changes in weather, ecology, and the amount of daylight. The growing season is that portion of the year in which local conditions (i.e. rainfall, temperature, daylight) permit normal plant growth. Whil ...
, 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 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 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
Kenozersky National Park (russian: Кенозерский национальный парк) is a national park in the north of Russia, located in Kargopolsky and Plesetsky Districts of Arkhangelsk Oblast. It was established December 28, 1 ...
near
Plesetsk
Plesetsk (russian: Плесе́цк) is an urban locality (a work settlement) and the administrative center of Plesetsky District, Arkhangelsk Oblast, Russia, situated about northeast of Moscow and south of Arkhangelsk. Municipally, it is ...
, Arkhangelsk Province, Russia, on average has 108 frost-free days.
The longest growing season 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
An ecotone is a transition area between two biological communities, where two communities meet and integrate. It may be narrow or wide, and it may be local (the zone between a field and forest) or regional (the transition between forest and gras ...
, 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 the warmest month of the year usually is or less.
High
latitude
In geography, latitude is a coordinate that specifies the north– south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from –90° at the south pole to 90° at the north pol ...
s mean that the
sun
The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...
does not rise far above the horizon, and less
solar energy
Solar energy is radiant light and heat from the Sun that is harnessed using a range of technologies such as solar power to generate electricity, solar thermal energy (including solar water heating), and solar architecture. It is an essenti ...
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 the dark winters, depending on latitude. The areas of the taiga inside the
Arctic Circle
The Arctic Circle is one of the two polar circles, and the most northerly of the five major circles of latitude as shown on maps of Earth. Its southern equivalent is the Antarctic Circle.
The Arctic Circle marks the southernmost latitude at w ...
have
midnight sun
The midnight sun is a natural phenomenon that occurs in the summer months in places north of the Arctic Circle or south of the Antarctic Circle, when the Sun remains visible at the local midnight. When the midnight sun is seen in the Arctic, t ...
in mid-summer and
polar night
The polar night is a phenomenon where the nighttime lasts for more than 24 hours that occurs in the northernmost and southernmost regions of Earth. This occurs only inside the polar circles. The opposite phenomenon, the polar day, or midnig ...
in mid-winter.
Precipitation
The taiga experiences relatively low
precipitation
In meteorology, precipitation is any product of the condensation of atmospheric water vapor that falls under gravitational pull from clouds. The main forms of precipitation include drizzle, rain, sleet, snow, ice pellets, graupel and hail. ...
throughout the year (generally annually, in some areas), primarily as
rain
Rain is water droplets that have condensed from atmospheric water vapor and then fall under gravity. Rain is a major component of the water cycle and is responsible for depositing most of the fresh water on the Earth. It provides water f ...
during the summer months, but also as
snow
Snow comprises individual ice crystals that grow while suspended in the atmosphere—usually within clouds—and then fall, accumulating on the ground where they undergo further changes.
It consists of frozen crystalline water throughout ...
or
fog
Fog is a visible aerosol consisting of tiny water droplets or ice crystals suspended in the air at or near the Earth's surface. Reprint from Fog can be considered a type of low-lying cloud usually resembling stratus, and is heavily influ ...
. Snow may remain on 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
Evaporation is a type of vaporization that occurs on the surface of a liquid as it changes into the gas phase. High concentration of the evaporating substance in the surrounding gas significantly slows down evaporation, such as when humidi ...
is consequently low for most of the year, annual precipitation exceeds evaporation, and is sufficient to sustain the dense vegetation growth including large trees. This explains the striking difference in biomass per square metre between the Taiga and the
Steppe
In physical geography, a steppe () is an ecoregion characterized by grassland plains without trees apart from those near rivers and lakes.
Steppe biomes may include:
* the montane grasslands and shrublands biome
* the temperate grasslands, ...
biomes, (in warmer climates), where evapotranspiration exceeds precipitation, restricting vegetation to mostly grasses.
In general, taiga grows to the south of the July isotherm, occasionally as far north as the July isotherm, with the southern limit more variable. Depending on rainfall, and taiga may be replaced by
forest steppe
A forest steppe is a temperate-climate ecotone and habitat type composed of grassland interspersed with areas of woodland or forest.
Locations
Forest steppe primarily occurs in a belt of forest steppes across northern Eurasia from the eastern ...
south of the July isotherm where rainfall is very low, but more typically extends south to the July isotherm, and locally where rainfall is higher, such as in eastern
Siberia
Siberia ( ; rus, Сибирь, r=Sibir', p=sʲɪˈbʲirʲ, a=Ru-Сибирь.ogg) is an extensive geographical region, constituting all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has been a part of ...
and adjacent
Outer Manchuria
Outer Manchuria (russian: Приаму́рье, translit=Priamurye; zh, s=外满洲, t=外滿洲, p=Wài Mǎnzhōu), or Outer Northeast China ( zh, s=外东北, t=外東北, p=Wài Dōngběi), refers to a territory in Northeast Asia that is now ...
, south to the July isotherm. In these warmer areas the taiga has higher species diversity, with more warmth-loving species such as
Korean pine
''Pinus koraiensis'' is a species of pine known commonly as the Korean pine. It is native to eastern Asia: Korea, northeastern China, Mongolia, the temperate rainforests of the Russian Far East, and central Japan. In the north of its range, it g ...
,
Jezo spruce
''Picea jezoensis'' (sometimes misspelled ''Picea yezoensis''), the dark-bark spruce, Ezo spruce, Yezo spruce, or Jezo spruce, is a large evergreen tree growing to 30–50 m tall and with a trunk diameter of up to 2 m. It is native to northeast ...
, and
Manchurian fir
''Abies holophylla'', also called needle fir or Manchurian fir, is a species of fir native to mountainous regions of northern Korea, southern Ussuriland, and China in the provinces of Heilongjiang, Jilin, and Liaoning.
It is an evergreen conif ...
Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...
coasts of North America and Asia), into coniferous
temperate rainforest
Temperate rainforests are coniferous or broadleaf forests that occur in the temperate zone and receive heavy rain.
Temperate rain forests occur in oceanic moist regions around the world: the Pacific temperate rain forests of North American ...
s where oak and hornbeam appear and join the conifers, birch and
Populus tremula
''Populus tremula'' (commonly called aspen, common aspen, Eurasian aspen, European aspen, or quaking aspen) is a species of poplar native to cool temperate regions of Europe and Asia, from Iceland and the British IslesJames KilkellIrish native ...
.
Glaciation
The area currently classified as taiga in Europe and North America (except Alaska) was recently glaciated. As the glaciers receded they left depressions in the topography that have since filled with water, creating
lake
A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much large ...
muskeg
Muskeg (Ojibwe: mashkiig; cr, maskīk; french: fondrière de mousse, lit. ''moss bog'') is a peat-forming ecosystem found in several northern climates, most commonly in Arctic and boreal areas. Muskeg is approximately synonymous with bog or ...
soil) found throughout the taiga.
Soils
Taiga
soil
Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former te ...
tends to be young and poor in nutrients, lacking the deep, organically enriched
profile
Profile or profiles may refer to:
Art, entertainment and media Music
* ''Profile'' (Jan Akkerman album), 1973
* ''Profile'' (Githead album), 2005
* ''Profile'' (Pat Donohue album), 2005
* ''Profile'' (Duke Pearson album), 1959
* '' ''Profi ...
present in temperate deciduous forests.Sayre, 19. The colder climate hinders development of soil, and 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
Tropical rainforests are rainforests that occur in areas of tropical rainforest climate in which there is no dry season – all months have an average precipitation of at least 60 mm – and may also be referred to as ''lowland equatori ...
.
Fallen leaves and
moss
Mosses are small, non-vascular flowerless plants in the taxonomic division Bryophyta (, ) '' sensu stricto''. Bryophyta (''sensu lato'', Schimp. 1879) may also refer to the parent group bryophytes, which comprise liverworts, mosses, and hor ...
can remain on the
forest floor
The forest floor, also called detritus, duff and the O horizon, is one of the most distinctive features of a forest ecosystem. It mainly consists of shed vegetative parts, such as leaves, branches, bark, and stems, existing in various stages ...
for a long time in the cool, moist climate, which limits their organic contribution to the soil.
Acid
In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a sequ ...
s from
evergreen
In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, which ...
spodosol
In soil science, podzols are the typical soils of coniferous or boreal forests and also the typical soils of eucalypt forests and heathlands in southern Australia. In Western Europe, podzols develop on heathland, which is often a construct of huma ...
, also known as
podzol
In soil science, podzols are the typical soils of coniferous or boreal forests and also the typical soils of eucalypt forests and heathlands in southern Australia. In Western Europe, podzols develop on heathland, which is often a construct of ...
, and the acidic forest floor often has only
lichens
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among hypha, filaments of multiple fungus, fungi species in a mutualism (biology), mutualistic relationship.
Since
North America
North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...
and
Eurasia
Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelago a ...
were originally connected by the
Bering land bridge
Beringia is defined today as the land and maritime area bounded on the west by the Lena River in Russia; on the east by the Mackenzie River in Canada; on the north by 72 degrees north latitude in the Chukchi Sea; and on the south by the tip of ...
, a number of animal and plant
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
(more animals than plants) were able to colonize both land masses, and are globally-distributed throughout the taiga biome (see
Circumboreal Region
The Circumboreal Region in phytogeography is a floristic region within the Holarctic Kingdom in Eurasia and North America, as delineated by such geobotanists as Josias Braun-Blanquet and Armen Takhtajan.
It is the largest floristic region i ...
). Others differ regionally (typically with each
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
having several distinct species), each occupying different regions of the taiga. Taigas also have some small-leaved
deciduous
In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, aft ...
trees, like
birch
A birch is a thin-leaved deciduous hardwood tree of the genus ''Betula'' (), in the family Betulaceae, which also includes alders, hazels, and hornbeams. It is closely related to the beech-oak family Fagaceae. The genus ''Betula'' contains 30 ...
,
alder
Alders are trees comprising the genus ''Alnus'' in the birch family Betulaceae. The genus comprises about 35 species of monoecious trees and shrubs, a few reaching a large size, distributed throughout the north temperate zone with a few sp ...
,
willow
Willows, also called sallows and osiers, from the genus ''Salix'', comprise around 400 speciesMabberley, D.J. 1997. The Plant Book, Cambridge University Press #2: Cambridge. of typically deciduous trees and shrubs, found primarily on moist s ...
, and poplar; these grow mostly in areas further south of the most extreme winter weather. However, the
Dahurian larch
''Larix gmelinii'', the Dahurian larch or Gmelin larch, is a species of larch native to eastern Siberia and adjacent northeastern Mongolia, northeastern China (Heilongjiang), South Korea and North Korea.
Description
''Larix gmelinii'' is a m ...
tolerates the coldest winters of the Northern Hemisphere, in eastern Siberia. The very southernmost parts of the taiga may have trees such as
oak
An oak is a tree or shrub in the genus ''Quercus'' (; Latin "oak tree") of the beech family, Fagaceae. There are approximately 500 extant species of oaks. The common name "oak" also appears in the names of species in related genera, notably ''L ...
,
maple
''Acer'' () is a genus of trees and shrubs commonly known as maples. The genus is placed in the family Sapindaceae.Stevens, P. F. (2001 onwards). Angiosperm Phylogeny Website. Version 9, June 2008 nd more or less continuously updated since http ...
,
elm
Elms are deciduous and semi-deciduous trees comprising the flowering plant genus ''Ulmus'' in the plant family Ulmaceae. They are distributed over most of the Northern Hemisphere, inhabiting the temperate and tropical-montane regions of North ...
and
lime
Lime commonly refers to:
* Lime (fruit), a green citrus fruit
* Lime (material), inorganic materials containing calcium, usually calcium oxide or calcium hydroxide
* Lime (color), a color between yellow and green
Lime may also refer to:
Botany ...
scattered among the conifers, and there is usually a gradual transition into a temperate, mixed forest, such as the
eastern forest-boreal transition
Eastern may refer to:
Transportation
*China Eastern Airlines, a current Chinese airline based in Shanghai
*Eastern Air, former name of Zambia Skyways
*Eastern Air Lines, a defunct American airline that operated from 1926 to 1991
*Eastern Air Li ...
of eastern Canada. In the interior of the continents, with the driest climates, the boreal forests might grade into temperate
grassland
A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur natur ...
.
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
''Chamaenerion angustifolium'' is a perennial herbaceous flowering plant in the willowherb family Onagraceae. It is known in North America as fireweed, in some parts of Canada as great willowherb, in Britain and Ireland as rosebay willowherb. ...
and lupine. The other type is the lichen woodland or sparse taiga, with trees that are farther-spaced and
lichen
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.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), 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 is home to many types of
berries
A berry is a small, pulpy, and often edible fruit. Typically, berries are juicy, rounded, brightly colored, sweet, sour or tart, and do not have a stone or pit, although many pips or seeds may be present. Common examples are strawberries, rasp ...
. 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
Cranberries are a group of evergreen dwarf shrubs or trailing vines in the subgenus ''Oxycoccus'' of the genus ''Vaccinium''. In Britain, cranberry may refer to the native species ''Vaccinium oxycoccos'', while in North America, cranberry ...
and
cloudberry
''Rubus chamaemorus'' is a species of flowering plant in the rose family Rosaceae, native to cool temperate regions, alpine and arctic tundra and boreal forest. This herbaceous perennial produces amber-colored edible fruit similar to the blackbe ...
). Some berries can grow in both the taiga and the lower arctic (southern regions) tundra, such as
bilberry
Bilberries (), or sometimes European blueberries, are a primarily Eurasian species of low-growing shrubs in the genus ''Vaccinium'' (family Ericaceae), bearing edible, dark blue berries. The species most often referred to is '' Vaccinium myrtill ...
lingonberry
''Vaccinium vitis-idaea'', the lingonberry, partridgeberry, mountain cranberry or cowberry, is a small evergreen shrub in the heath family Ericaceae, that bears edible fruit. It is native to boreal forest and Arctic tundra throughout the Norther ...
.
The forests of the taiga are largely coniferous, dominated by
larch
Larches are deciduous conifers in the genus ''Larix'', of the family Pinaceae (subfamily Laricoideae). Growing from tall, they are native to much of the cooler temperate northern hemisphere, on lowlands in the north and high on mountains furt ...
,
spruce
A spruce is a tree of the genus ''Picea'' (), a genus of about 35 species of coniferous evergreen trees in the family Pinaceae, found in the northern temperate and boreal (taiga) regions of the Earth. ''Picea'' is the sole genus in the subfami ...
pine
A pine is any conifer tree or shrub in the genus ''Pinus'' () of the family Pinaceae. ''Pinus'' is the sole genus in the subfamily Pinoideae. The World Flora Online created by the Royal Botanic Gardens, Kew and Missouri Botanical Garden accep ...
. The woodland mix varies according to geography and climate; for example, the
Eastern Canadian forests
The Eastern Canadian forests is a taiga ecoregion in Eastern Canada, as defined by the World Wildlife Fund (WWF) categorization system.
Setting
This ecoregion contains a number of mountainous areas on the east coast of Canada and along the Saint ...
ecoregion (of the higher elevations of the
Laurentian Mountains
The Laurentian Mountains (French: ''Laurentides'') are a mountain range in southern Quebec, Canada, north of the St. Lawrence River and Ottawa River, rising to a highest point of at Mont Raoul Blanchard, northeast of Quebec City in the Laurentid ...
and the northern
Appalachian Mountains
The Appalachian Mountains, often called the Appalachians, (french: Appalaches), are a system of mountains in eastern to northeastern North America. The Appalachians first formed roughly 480 million years ago during the Ordovician Period. They ...
) in Canada is dominated by balsam fir ''
Abies balsamea
''Abies balsamea'' or balsam fir is a North American fir, native to most of eastern and central Canada ( Newfoundland west to central Alberta) and the northeastern United States (Minnesota east to Maine, and south in the Appalachian Mountains to ...
'', while further north, the
Eastern Canadian Shield taiga
The Eastern Canadian Shield taiga is an ecoregion of Canada as defined by the World Wildlife Fund (WWF) categorization system.
Setting
Located in northeastern Canada, this ecoregion covers a large part of northern Quebec and most of Labrador, re ...
(of northern
Quebec
Quebec ( ; )According to the Canadian government, ''Québec'' (with the acute accent) is the official name in Canadian French and ''Quebec'' (without the accent) is the province's official name in Canadian English is one of the thirtee ...
and
Labrador
, nickname = "The Big Land"
, etymology =
, subdivision_type = Country
, subdivision_name = Canada
, subdivision_type1 = Province
, subdivision_name1 ...
) is mostly black spruce ''
Picea mariana
''Picea mariana'', the black spruce, is a North American species of spruce tree in the pine family. It is widespread across Canada, found in all 10 provinces and all 3 territories. It is the official tree of the province of Newfoundland and Labr ...
Evergreen
In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, which ...
species in the taiga (spruce, fir, and pine) have a number of adaptations specifically for survival in harsh taiga winters, although larch, which is extremely cold-tolerant, is
deciduous
In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, aft ...
. Taiga trees tend to have shallow roots to take advantage of the thin soils, while many of them seasonally alter their
biochemistry
Biochemistry or biological chemistry is the study of chemical processes within and relating to living organisms. A sub-discipline of both chemistry and biology, biochemistry may be divided into three fields: structural biology, enzymology and ...
to make them more resistant to freezing, called "hardening".Sayre, 23. The narrow conical shape of northern conifers, and their downward-drooping limbs, also help them shed snow.
Because the sun is low in the horizon for most of the year, it is difficult for plants to generate energy from
photosynthesis
Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities. Some of this chemical energy is stored i ...
. 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
Transpiration is the process of water movement through a plant and its evaporation from aerial parts, such as leaves, stems and flowers. Water is necessary for plants but only a small amount of water taken up by the roots is used for growth a ...
and their dark green color increases their absorption of sunlight. Although precipitation 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
A birch is a thin-leaved deciduous hardwood tree of the genus ''Betula'' (), in the family Betulaceae, which also includes alders, hazels, and hornbeams. It is closely related to the beech-oak family Fagaceae. The genus ''Betula'' contains 30 ...
,
aspen
Aspen is a common name for certain tree species; some, but not all, are classified by botanists in the section ''Populus'', of the '' Populus'' genus.
Species
These species are called aspens:
*'' Populus adenopoda'' – Chinese aspen (Chin ...
,
willow
Willows, also called sallows and osiers, from the genus ''Salix'', comprise around 400 speciesMabberley, D.J. 1997. The Plant Book, Cambridge University Press #2: Cambridge. of typically deciduous trees and shrubs, found primarily on moist s ...
, and
rowan
The rowans ( or ) or mountain-ashes are shrubs or trees in the genus ''Sorbus
''Sorbus'' is a genus of over 100 species of trees and shrubs in the rose family, Rosaceae. Species of ''Sorbus'' (''s.l.'') are commonly known as whitebeam, r ...
. Many smaller
herbaceous
Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials.
Definitions of "herb" and "herbaceous"
The fourth edition of t ...
plants, such as
fern
A fern (Polypodiopsida or Polypodiophyta ) is a member of a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. The polypodiophytes include all living pteridophytes except t ...
s and occasionally
ramps
An inclined plane, also known as a ramp, is a flat supporting surface tilted at an angle from the vertical direction, with one end higher than the other, used as an aid for raising or lowering a load. The inclined plane is one of the six clas ...
grow closer to the ground. Periodic stand-replacing
wildfire
A wildfire, forest fire, bushfire, wildland fire or rural fire is an unplanned, uncontrolled and unpredictable fire in an area of Combustibility and flammability, combustible vegetation. Depending on the type of vegetation present, a wildfire ...
s (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
Jack pine (''Pinus banksiana'') is an eastern North American pine. Its native range in Canada is east of the Rocky Mountains from the Mackenzie River in the Northwest Territories to Cape Breton Island in Nova Scotia, and the north-central and ...
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
''Morchella'', the true morels, is a genus of edible sac fungi closely related to anatomically simpler cup fungi in the order Pezizales (division Ascomycota). These distinctive fungi have a honeycomb appearance due to the network of ridges ...
) are also known to do this.
Grass
Poaceae () or Gramineae () is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos and the grasses of natural grassland and species cultivated in lawns an ...
es grow wherever they can find a patch of sun;
moss
Mosses are small, non-vascular flowerless plants in the taxonomic division Bryophyta (, ) '' sensu stricto''. Bryophyta (''sensu lato'', Schimp. 1879) may also refer to the parent group bryophytes, which comprise liverworts, mosses, and hor ...
Scots pine
''Pinus sylvestris'', the Scots pine (UK), Scotch pine (US) or Baltic pine, is a species of tree in the pine family Pinaceae that is native to Eurasia. It can readily be identified by its combination of fairly short, blue-green leaves and orang ...
is a common component of the taiga, while taiga of the
Russian Far East
The Russian Far East (russian: Дальний Восток России, r=Dal'niy Vostok Rossii, p=ˈdalʲnʲɪj vɐˈstok rɐˈsʲiɪ) is a region in Northeast Asia. It is the easternmost part of Russia and the Asian continent; and is admini ...
and
Mongolia
Mongolia; Mongolian script: , , ; lit. "Mongol Nation" or "State of Mongolia" () is a landlocked country in East Asia, bordered by Russia to the north and China to the south. It covers an area of , with a population of just 3.3 million, ...
is dominated by
larch
Larches are deciduous conifers in the genus ''Larix'', of the family Pinaceae (subfamily Laricoideae). Growing from tall, they are native to much of the cooler temperate northern hemisphere, on lowlands in the north and high on mountains furt ...
. 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
''Populus tremula'' (commonly called aspen, common aspen, Eurasian aspen, European aspen, or quaking aspen) is a species of poplar native to cool temperate regions of Europe and Asia, from Iceland and the British IslesJames KilkellIrish native ...
''.
Fauna
The boreal forest/taiga supports 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
Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...
, 130 species of fish, and an estimated 32,000 species of
insect
Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pairs ...
s. Insects play a critical role as
pollinator
A pollinator is an animal that moves pollen from the male anther of a flower to the female stigma of a flower. This helps to bring about fertilization of the ovules in the flower by the male gametes from the pollen grains.
Insects are the maj ...
s,
decompose
Decomposition or rot is the process by which dead organic substances are broken down into simpler organic or inorganic matter such as carbon dioxide, water, simple sugars and mineral salts. The process is a part of the nutrient cycle and is ...
rs, and as a part of the food web. Many nesting birds, rodents, and small carnivorous mammals rely on them for food in the summer months. The cold winters (and short summers) make the taiga a challenging biome for
reptile
Reptiles, as most commonly defined are the animals in the class Reptilia ( ), a paraphyletic grouping comprising all sauropsids except birds. Living reptiles comprise turtles, crocodilians, squamates (lizards and snakes) and rhynchocephalians ( ...
s and
amphibian
Amphibians are tetrapod, four-limbed and ectothermic vertebrates of the Class (biology), class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terres ...
s, 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
The red-sided garter snake (''Thamnophis sirtalis parietalis'') is a subspecies of the common garter snake, in the subfamily Natricinae of the family Colubridae. This slender subspecies of natricine snake is indigenous to North America and i ...
,
common European adder
''Vipera berus'', the common European adderMallow D, Ludwig D, Nilson G. (2003). ''True Vipers: Natural History and Toxinology of Old World Vipers''. Malabar, Florida: Krieger Publishing Company. . or common European viper,Stidworthy J. (1974). ...
,
blue-spotted salamander
The blue-spotted salamander (''Ambystoma laterale'') is a mole salamander native to the Great Lakes states and northeastern United States, and parts of Ontario and Quebec in Canada. Their range is known to extend to James Bay to the north, an ...
Siberian salamander
''Salamandrella keyserlingii'', the Siberian salamander, is a species of salamander found in Northeast Asia. It lives in Wet woodland, wet woods and riparian groves.
Distribution
It is found primarily in Siberia east of the Sosva River and t ...
,
wood frog
''Lithobates sylvaticus'' or ''Rana sylvatica'', commonly known as the wood frog, is a frog species that has a broad distribution over North America, extending from the boreal forest of the north to the southern Appalachians, with several nota ...
,
northern leopard frog
''Lithobates pipiens''Integrated Taxonomic Information System nternet2012''Lithobates pipiens'' pdated 2012 Sept; cited 2012 Dec 26Available from: www.itis.gov/ or ''Rana pipiens'', commonly known as the northern leopard frog, is a species of le ...
American toad
The American toad (''Anaxyrus americanus'') is a common species of toad found throughout Canada and the eastern United States. It is divided into three subspecies: the eastern American toad (''A. a. americanus''), the dwarf American toad (''A. a ...
, and Canadian toad. Most hibernate underground in winter. Fish of 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
The Alaska blackfish (''Dallia pectoralis'') is a species of freshwater fish in the esocid family ( Esocidae) of order Esociformes. It inhabits Arctic regions of Alaska as well as Siberia and the Bering Sea islands.
Description
Alaska blackfish ...
,
northern pike
The northern pike (''Esox lucius'') is a species of carnivorous fish of the genus '' Esox'' (the pikes). They are typical of brackish and fresh waters of the Northern Hemisphere (''i.e.'' holarctic in distribution). They are known simply as a ...
,
walleye
The walleye (''Sander vitreus'', synonym ''Stizostedion vitreum''), also called the yellow pike or yellow pickerel, is a freshwater perciform fish native to most of Canada and to the Northern United States. It is a North American close relat ...
,
longnose sucker
The longnose sucker (''Catostomus catostomus'') is a species of cypriniform freshwater fish in the family Catostomidae. It is native to North America from the northern United States to the top of the continent. It is also found in Russia in ri ...
,
white sucker
The white sucker (''Catostomus commersonii)'' is a species of freshwater cypriniform fish inhabiting the upper Midwest and Northeast in North America, but it is also found as far south as Georgia and as far west as New Mexico. The fish is common ...
, various species of
cisco
Cisco Systems, Inc., commonly known as Cisco, is an American-based multinational digital communications technology conglomerate corporation headquartered in San Jose, California. Cisco develops, manufactures, and sells networking hardware, ...
,
lake whitefish
The lake whitefish (''Coregonus clupeaformis'') is a species of freshwater whitefish from North America. Lake whitefish are found throughout much of Canada and parts of the northern United States, including all of the Great Lakes. The lake white ...
,
round whitefish
The round whitefish (''Prosopium cylindraceum'') is a freshwater species of fish that is found in lakes from Alaska to New England, including the Great Lakes. It has an olive-brown back with light silvery sides and underside and its length is ge ...
,
pygmy whitefish
The pygmy whitefish (''Prosopium coulterii'') is a freshwater whitefish of the genus ''Prosopium'' in the family Salmonidae. Found in the mountain streams and lakes in western North America, it also has isolated populations in Lake Superior and i ...
brook trout
The brook trout (''Salvelinus fontinalis'') is a species of freshwater fish in the char genus ''Salvelinus'' of the salmon family Salmonidae. It is native to Eastern North America in the United States and Canada, but has been introduced elsewhere ...
(including sea-run brook trout in the Hudson Bay area),
chum salmon
The chum salmon (''Oncorhynchus keta''), also known as dog salmon or keta salmon, is a species of anadromous salmonid fish from the genus '' Oncorhynchus'' (Pacific salmon) native to the coastal rivers of the North Pacific and the Beringian A ...
lenok
Lenoks, otherwise known as Asiatic trout or Manchurian trout,James Card: Fly fishing in South Korea.' Retrieved 22 June 2015. are salmonid fish of the genus ''Brachymystax'', native to rivers and lakes in Mongolia, Kazakhstan, wider Siberia (incl ...
and
lake chub
The lake chub (''Couesius plumbeus'') is a freshwater cyprinid fish found in Canada and in parts of the United States. Of all North American minnows, it is the one with the northernmost distribution. Its genus, ''Couesius'' is considered mono ...
.
The taiga is mainly home to a number of large
herbivorous
A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpart ...
mammal
Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...
s, such as ''Alces alces'' (
moose
The moose (in North America) or elk (in Eurasia) (''Alces alces'') is a member of the New World deer subfamily and is the only species in the genus ''Alces''. It is the largest and heaviest extant species in the deer family. Most adult ma ...
), and a few subspecies of ''Rangifer tarandus'' (
reindeer
Reindeer (in North American English, known as caribou if wild and ''reindeer'' if domesticated) are deer in the genus ''Rangifer''. For the last few decades, reindeer were assigned to one species, ''Rangifer tarandus'', with about 10 subspe ...
in Eurasia);
caribou
Reindeer (in North American English, known as caribou if wild and ''reindeer'' if domesticated) are deer in the genus ''Rangifer''. For the last few decades, reindeer were assigned to one species, ''Rangifer tarandus'', with about 10 subspe ...
in North America). Some areas of the more southern closed boreal forest have populations of other
Cervidae
Deer or true deer are hoofed ruminant mammals forming the family Cervidae. The two main groups of deer are the Cervinae, including the muntjac, the elk (wapiti), the red deer, and the fallow deer; and the Capreolinae, including the reindeer ...
elk
The elk (''Cervus canadensis''), also known as the wapiti, is one of the largest species within the deer family, Cervidae, and one of the largest terrestrial mammals in its native range of North America and Central and East Asia. The common ...
,
Sitka black-tailed deer
The Sitka deer or Sitka black-tailed deer (''Odocoileus hemionus sitkensis'') is a subspecies of mule deer (''Odocoileus hemionus''), similar to the Columbian black-tailed subspecies (''O. h. colombianus''). Their name originates from Sitka, ...
, and
roe deer
The roe deer (''Capreolus capreolus''), also known as the roe, western roe deer, or European roe, is a species of deer. The male of the species is sometimes referred to as a roebuck. The roe is a small deer, reddish and grey-brown, and well-adapt ...
. While normally a polar species, some southern herds of
muskoxen
The muskox (''Ovibos moschatus'', in Latin "musky sheep-ox"), also spelled musk ox and musk-ox, plural muskoxen or musk oxen (in iu, ᐅᒥᖕᒪᒃ, umingmak; in Woods Cree: ), is a hoofed mammal of the family Bovidae. Native to the Arctic, i ...
reside in the taiga of Russia's Far East and North America. The
Amur
The Amur (russian: река́ Аму́р, ), or Heilong Jiang (, "Black Dragon River", ), is the world's List of longest rivers, tenth longest river, forming the border between the Russian Far East and Northeast China, Northeastern China (Inne ...
-Kamchatka region of far eastern Russia also supports the
snow sheep
The snow sheep (''Ovis nivicola''), or Siberian bighorn sheep, is a species of sheep from the mountainous areas in the northeast of Siberia. One subspecies, the Putorana snow sheep ''(Ovis nivicola borealis)'', lives isolated from the other forms ...
, the Russian relative of the American
bighorn sheep
The bighorn sheep (''Ovis canadensis'') is a species of sheep native to North America. It is named for its large horns. A pair of horns might weigh up to ; the sheep typically weigh up to . Recent genetic testing indicates three distinct subspec ...
,
wild boar
The wild boar (''Sus scrofa''), also known as the wild swine, common wild pig, Eurasian wild pig, or simply wild pig, is a suid native to much of Eurasia and North Africa, and has been introduced to the Americas and Oceania. The species is ...
, and
long-tailed goral
The long-tailed goral or Amur goral (''Naemorhedus caudatus'') is a species of ungulate of the family Bovidae found in the mountains of eastern and northern Asia, including Russia, China, and Korea. A population of this species exists in the Kore ...
. The largest animal in the taiga is the
wood bison
The wood bison (''Bison bison athabascae'') or mountain bison (often called the wood buffalo or mountain buffalo), is a distinct northern subspecies or ecotype of the American bison. Its original range included much of the boreal forest regions ...
of northern Canada/Alaska; additionally, some numbers of the American
plains bison
The Plains bison (''Bison bison bison'') is one of two subspecies/ecotypes of the American bison, the other being the wood bison (''B. b. athabascae''). A natural population of Plains bison survives in Yellowstone National Park (the Yellowstone ...
have been introduced into the Russian far-east, as part of the taiga regeneration project called ''
Pleistocene Park
Pleistocene Park (russian: Плейстоценовый парк, Pleystotsenovyy park) is a nature reserve on the Kolyma River south of Chersky in the Sakha Republic, Russia, in northeastern Siberia, where an attempt is being made to re-crea ...
'', in addition to Przsewalski's horse. Small mammals of the taiga biome include
rodent
Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are na ...
species such as the
beaver
Beavers are large, semiaquatic rodents in the genus ''Castor'' native to the temperate Northern Hemisphere. There are two extant species: the North American beaver (''Castor canadensis'') and the Eurasian beaver (''C. fiber''). Beavers ar ...
chipmunk
Chipmunks are small, striped rodents of the family Sciuridae. Chipmunks are found in North America, with the exception of the Siberian chipmunk which is found primarily in Asia.
Taxonomy and systematics
Chipmunks may be classified either as ...
,
marmot
Marmots are large ground squirrels in the genus ''Marmota'', with 15 species living in Asia, Europe, and North America. These herbivores are active during the summer, when they can often be found in groups, but are not seen during the winter, ...
,
lemming
A lemming is a small rodent, usually found in or near the Arctic in tundra biomes. Lemmings form the subfamily Arvicolinae (also known as Microtinae) together with voles and muskrats, which form part of the superfamily Muroidea, which also includ ...
,
North American porcupine
The North American porcupine (''Erethizon dorsatum''), also known as the Canadian porcupine, is a large quill-covered rodent in the New World porcupine family. It is the second largest rodent in North America, after the North American beaver ('' ...
and
vole
Voles are small rodents that are relatives of lemmings and hamsters, but with a stouter body; a longer, hairy tail; a slightly rounder head; smaller eyes and ears; and differently formed molars (high-crowned with angular cusps instead of low-c ...
; as well as a small number of
lagomorph
The lagomorphs are the members of the taxonomic order Lagomorpha, of which there are two living families: the Leporidae (hares and rabbits) and the Ochotonidae (pikas). The name of the order is derived from the Ancient Greek ''lagos'' (λαγ ...
species, such as the
pika
A pika ( or ; archaically spelled pica) is a small, mountain-dwelling mammal found in Asia and North America. With short limbs, very round body, an even coat of fur, and no external tail, they resemble their close relative, the rabbit, but wi ...
,
snowshoe hare
The snowshoe hare (''Lepus americanus''), also called the varying hare or snowshoe rabbit, is a species of hare found in North America. It has the name "snowshoe" because of the large size of its hind feet. The animal's feet prevent it from sin ...
and
mountain hare
The mountain hare (''Lepus timidus''), also known as blue hare, tundra hare, variable hare, white hare, snow hare, alpine hare, and Irish hare, is a Palearctic hare that is largely adapted to polar and mountainous habitats.
Evolution
The mount ...
. These species have adapted to survive the harsh winters in their native ranges. Some larger mammals, such as
bear
Bears are carnivoran mammals of the family Ursidae. They are classified as caniforms, or doglike carnivorans. Although only eight species of bears are extant, they are widespread, appearing in a wide variety of habitats throughout the Nor ...
s, eat heartily during the summer in order to gain weight, and then go into
hibernation
Hibernation is a state of minimal activity and metabolic depression undergone by some animal species. Hibernation is a seasonal heterothermy characterized by low body-temperature, slow breathing and heart-rate, and low metabolic rate. It most ...
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
raccoon
The raccoon ( or , ''Procyon lotor''), sometimes called the common raccoon to distinguish it from other species, is a mammal native to North America. It is the largest of the procyonid family, having a body length of , and a body weight of ...
s). Mammalian predators of the taiga include
Canada lynx
The Canada lynx (''Lynx canadensis''), or Canadian lynx, is a medium-sized North American lynx that ranges across Alaska, Canada, and northern areas of the contiguous United States. It is characterized by its long, dense fur, triangular ears ...
,
Eurasian lynx
The Eurasian lynx (''Lynx lynx'') is a medium-sized wild cat widely distributed from Northern, Central and Eastern Europe to Central Asia and Siberia, the Tibetan Plateau and the Himalayas. It inhabits temperate and boreal forests up to an eleva ...
,
stoat
The stoat (''Mustela erminea''), also known as the Eurasian ermine, Beringian ermine and ermine, is a mustelid native to Eurasia and the northern portions of North America. Because of its wide circumpolar distribution, it is listed as Least Conc ...
,
Siberian weasel
The Siberian weasel or kolonok (''Mustela sibirica''), is a medium-sized weasel native to Asia, where it is widely distributed and inhabits various forest habitats and open areas. It is therefore listed as Least Concern on the IUCN Red List.
Desc ...
sable
The sable (''Martes zibellina'') is a species of marten, a small omnivorous mammal primarily inhabiting the forest environments of Russia, from the Ural Mountains throughout Siberia, and northern Mongolia. Its habitat also borders eastern Kaza ...
North American river otter
The North American river otter (''Lontra canadensis''), also known as the northern river otter and river otter, is a semiaquatic mammal that only lives on the North American continent, along its waterways and coasts. An adult North American rive ...
,
European otter
The Eurasian otter (''Lutra lutra''), also known as the European otter, Eurasian river otter, common otter, and Old World otter, is a semiaquatic mammal native to Eurasia. The most widely distributed member of the otter subfamily (Lutrinae) of th ...
,
American mink
The American mink (''Neogale vison'') is a semiaquatic species of mustelid native to North America, though human intervention has expanded its range to many parts of Europe, Asia and South America. Because of range expansion, the American mink i ...
,
wolverine
The wolverine (), (''Gulo gulo''; ''Gulo'' is Latin for " glutton"), also referred to as the glutton, carcajou, or quickhatch (from East Cree, ''kwiihkwahaacheew''), is the largest land-dwelling species of the family Mustelidae. It is a muscul ...
,
Asian badger
The Asian badger (''Meles leucurus''), also known as the sand badger, is a species of badger native to Mongolia, China, Kazakhstan, Kyrgyzstan, the Korean Peninsula and Russia.
Characteristics
The Asian badger is mostly lighter in colour than ...
,
fisher
Fisher is an archaic term for a fisherman, revived as gender-neutral.
Fisher, Fishers or The Fisher may also refer to:
Places
Australia
*Division of Fisher, an electoral district in the Australian House of Representatives, in Queensland
*Elect ...
Mongolian wolf
The Mongolian wolf (''Canis lupus chanco'') is a subspecies of gray wolf which is native to Mongolia, northern and central China, Korea, and the Ussuri region of Russia.
Taxonomy
''Canis chanco'' was the scientific name proposed by John Edward ...
,
coyote
The coyote (''Canis latrans'') is a species of canis, canine native to North America. It is smaller than its close relative, the wolf, and slightly smaller than the closely related eastern wolf and red wolf. It fills much of the same ecologica ...
,
red fox
The red fox (''Vulpes vulpes'') is the largest of the true foxes and one of the most widely distributed members of the Order (biology), order Carnivora, being present across the entire Northern Hemisphere including most of North America, Europe ...
,
Arctic fox
The Arctic fox (''Vulpes lagopus''), also known as the white fox, polar fox, or snow fox, is a small fox native to the Arctic regions of the Northern Hemisphere and common throughout the Arctic tundra biome. It is well adapted to living in ...
,
grizzly bear
The grizzly bear (''Ursus arctos horribilis''), also known as the North American brown bear or simply grizzly, is a population or subspecies of the brown bear inhabiting North America.
In addition to the mainland grizzly (''Ursus arctos horri ...
,
American black bear
The American black bear (''Ursus americanus''), also called simply a black bear or sometimes a baribal, is a medium-sized bear endemic to North America. It is the continent's smallest and most widely distributed bear species. American black bear ...
,
Asiatic black bear
The Asian black bear (''Ursus thibetanus''), also known as the Asiatic black bear, moon bear and white-chested bear, is a medium-sized bear species
In biology, a species is the basic unit of classification and a taxonomic rank of an or ...
,
Ussuri brown bear
The Ussuri brown bear (''Ursus arctos lasiotus''), also known as the Ezo brown bear, Russian bear, or the black grizzly bear, is a subspecies of the brown bear or a population of the Eurasian brown bear (''U. a. arctos''). One of the largest b ...
,
polar bear
The polar bear (''Ursus maritimus'') is a hypercarnivorous bear whose native range lies largely within the Arctic Circle, encompassing the Arctic Ocean, its surrounding seas and surrounding land masses. It is the largest extant bear specie ...
(only small areas of northern taiga),
Siberian tiger
The Siberian tiger or Amur tiger is a population of the tiger subspecies ''Panthera tigris tigris'' native to the Russian Far East, Northeast China and possibly North Korea. It once ranged throughout the Korean Peninsula, but currently inhabit ...
, and Amur leopard.
More than 300 species of birds have their nesting grounds in the taiga. Siberian thrush, white-throated sparrow, and black-throated green warbler bird migration, migrate to this Habitat (ecology), habitat to take advantage of the long summer days and abundance of
insect
Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pairs ...
s 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 Bird of prey, raptors that can take live mammal prey, such as 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
Wildfire, Fire has been one of the most important factors shaping 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 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 the boreal forest is high-intensity crown fires or severe surface fires of very large size, often more than 10,000 ha (100 km2), and sometimes more than 400,000 ha (4000 km2). 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 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 a warmer climate.
The mature boreal forest pattern in the south shows Abies balsamea, balsam fir dominant on well-drained sites in eastern Canada changing centrally and westward to a prominence of Picea engelmannii, white spruce, with Picea mariana, black spruce and Larix laricina, tamarack forming the forests on peats, and with jack pine usually present on dry sites except in the extreme east, where it is absent. [E3680, Coates et al. 1994] The effects of fires are inextricably woven into 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
soil
Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former te ...
s provided Bryson et al. (1965) with clues about 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 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 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
Jack pine (''Pinus banksiana'') is an eastern North American pine. Its native range in Canada is east of the Rocky Mountains from the Mackenzie River in the Northwest Territories to Cape Breton Island in Nova Scotia, and the north-central and ...
, Pinus contorta, lodgepole pine,
aspen
Aspen is a common name for certain tree species; some, but not all, are classified by botanists in the section ''Populus'', of the '' Populus'' genus.
Species
These species are called aspens:
*'' Populus adenopoda'' – Chinese aspen (Chin ...
, Populus balsamifera, balsam poplar (''Populus balsamifera''), Betula papyrifera, paper birch, Larix laricina, tamarack, Picea mariana, 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 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 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 the peatlands.
Climate change
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 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 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 the 1960s: although this trend was weak or even non-existent in the eastern forests, it was particularly pronounced in the western coniferous forests. However, in 2016, a study found no overall Canadian boreal forest trend between 1950 and 2012: while it also found improved growth in some southern boreal forests and dampened growth in the north (contrary to what the hypothesis would suggest), those patterns were statistically weak. A 2018 Landsat reanalysis confirmed that there was a drying trend and a loss of forest in western Canadian forests and some greening in the wetter east, but it had also concluded that most of the forest loss attributed to climate change in the earlier studies had instead constituted a delayed response to anthropogenic disturbance. Subsequent research found that even in the forests where biomass trends did not change, there was a substantial shift towards the deciduous broad-leaved trees with higher drought tolerance over the past 65 years, and another Landsat analysis of 100,000 undisturbed sites found that the areas with low tree cover became greener in response to warming, but tree mortality (browning) became the dominant response as the proportion of existing tree cover increased.
While the majority of studies on boreal forest transitions have been done in Canada, similar trends have been detected in the other countries. Summer warming has been shown to increase water stress and reduce tree growth in dry areas of the southern boreal forest in central Alaska and portions of far eastern Russia.In Siberia, the taiga is converting from predominantly needle-shedding larch trees to evergreen conifers in response to a warming climate. This is likely to further accelerate warming, as the evergreen trees will absorb more of the sun's rays. Given the vast size of the area, such a change has the potential to affect areas well outside of the region. In much of the boreal forest in Alaska, the growth of white spruce trees are stunted by unusually warm summers, while trees on some of the coldest fringes of the forest are experiencing faster growth than previously. Lack of moisture in the warmer summers are also stressing the birch trees of central Alaska.
In addition to these observations, there has also been work on projecting future forest trends. A 2018 study of the seven tree species dominant in the Eastern Canadian forests found that while 2°C warming alone increases their growth by around 13% on average, water availability is much more important than temperature and further warming of up to 4°C would result in substantial declines unless matched by increases in precipitation. A 2019 study suggested that the forest plots commonly used to evaluate boreal forest response to climate change tend to have less evolutionary competition between trees than the typical forest, and that with strong competition, there was little net growth in response to warming. Climatic change only stimulated growth for trees under weak competition in central boreal forests. A 2021 paper had confirmed that the boreal forests are much more strongly affected by climate change than the other forest types in Canada and projected that most of the eastern Canadian boreal forests would reach a tipping point around 2080 under the Representative Concentration Pathway, RCP 8.5 scenario which represents the largest potential increase in anthropogenic emissions. Another 2021 study projected that under the "moderate" Shared Socioeconomic Pathways, SSP2-4.5 scenario, boreal forests would experience a 15% worldwide increase in biomass by the end of the century, but this would be more than offset by the 41% biomass decline in the tropics. In 2022, the results of a 5-year warming experiment in North America had shown that the juveniles of tree species which currently dominate the southern margins of the boreal forests fare the worst in response to even 1.5°C or +3.1 °C of warming and the associated reductions in precipitation. While the temperate species which would benefit from such conditions are also present in the southern boreal forests, they are both rare and have slower growth rates.
A 2022 assessment of tipping points in the climate system designated two inter-related tipping points associated with climate change - the die-off of taiga at its southern edge and the area's consequent reversion to
grassland
A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur natur ...
(similar to the Amazon rainforest dieback) and the opposite process to the north, where the rapid warming of the adjacent
tundra
In physical geography, tundra () is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. The term ''tundra'' comes through Russian (') from the Kildin Sámi word (') meaning "uplands", "treeless moun ...
areas converts them to taiga. While both of these processes can already be observed today, the assessment believes that they would likely not become unstoppable (and thus meet the definition of a tipping point) until global warming of around 4 °C. However, the certainty level is still limited and it is possible that 1.5 °C would be sufficient for either tipping point; on the other hand, the southern die-off may not be inevitable until 5 °C, while the replacement of tundra with taiga may require 7.2°C. Once the "right" level of warming is met, either process would take at least 40-50 years to finish, and is more likely to unfold over a century or more. While the southern die-off would involve the loss of around 52 billion tons of carbon, the net result is ''cooling'' of around 0.18°C globally and between 0.5°C to 2°C regionally. Likewise, boreal forest expansion into tundra has a net global warming effect of around 0.14°C globally and 0.5°C to 1°C regionally, even though new forest growth captures around 6 billion tons of carbon. In both cases, this is due to the snow-covered ground having a much greater albedo than the forests.
Other threats
Human activities
Some of the larger cities situated in this biome are Murmansk, Arkhangelsk, Yakutsk, Anchorage, Alaska, Anchorage, Yellowknife, Tromsø, Luleå, and Oulu.
Large areas of
Siberia
Siberia ( ; rus, Сибирь, r=Sibir', p=sʲɪˈbʲirʲ, a=Ru-Сибирь.ogg) is an extensive geographical region, constituting all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has been a part of ...
's taiga have been harvested for lumber since the collapse of the Soviet Union. Previously, the forest was protected by the restrictions of the Soviet Forest Ministry, but with the collapse of the Union, the restrictions regarding trade with Western nations have vanished. Trees are easy to harvest and sell well, so loggers have begun harvesting Russian taiga evergreen trees for sale to nations previously forbidden by Soviet law.
In
Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...
, only eight percent of the taiga is protected from development, and the provincial governments allows clearcutting to occur on Crown land, which destroys the forest in large blocks. The blocks are replanted with monocrop seedlings in the following season, but the trees do not grow back for many years, and the forest ecosystem is radically changed for hundreds of years. Products from logged boreal forests include toilet paper, copy paper, newsprint, and lumber. More than 90% of boreal forest products from Canada are exported for consumption and processing in the United States.
Most companies that harvest in Canadian forests use some certification by agencies such as the Forest Stewardship Council (FSC), Sustainable Forests Initiative (SFI), or the Canadian Standards Association (CSA), in their marketing. While the certification process differs between these groups, all of them include some mention of undefined "forest stewardship", "respect for aboriginal peoples", and compliance with local, provincial or national environmental laws, forest worker safety, education and training, and other issues. The certification is largely about tracking, to ensure traceability, and does not de-certify lumber obtained from clearcuts, or taken without the consent of aboriginal peoples.
Insects
Recent years have seen outbreaks of insect pests in forest-destroying plagues: the spruce-bark beetle (''Dendroctonus rufipennis'') in
Yukon
Yukon (; ; formerly called Yukon Territory and also referred to as the Yukon) is the smallest and westernmost of Canada's three territories. It also is the second-least populated province or territory in Canada, with a population of 43,964 as ...
and Alaska; the mountain pine beetle in British Columbia; the
aspen
Aspen is a common name for certain tree species; some, but not all, are classified by botanists in the section ''Populus'', of the '' Populus'' genus.
Species
These species are called aspens:
*'' Populus adenopoda'' – Chinese aspen (Chin ...
-leaf miner; the larch sawfly; the spruce budworm (''Choristoneura fumiferana''); the spruce coneworm.
Pollution
The effect of Sulfur dioxide, sulphur dioxide on woody boreal forest species was investigated by Addison et al. (1984),Addison, P.A.; Malhotra, S.S.; Khan, A.A. 1984. "Effect of sulfur dioxide on woody boreal forest species grown on native soils and tailings". ''J. Environ. Qual.'' 13(3):333–36. who exposed plants growing on native soils and tailings to 15.2 μmol/m3 (0.34 ppm) of SO2 on CO2 assimilation rate (NAR). The Canadian maximum acceptable limit for atmospheric SO2 is 0.34 ppm. Fumigation with SO2 significantly reduced NAR in all species and produced visible symptoms of injury in 2–20 days. The decrease in NAR of deciduous species (trembling aspen [''Populus tremuloides''], willow [''Salix''], green alder [''Alnus viridis''], and white birch [''Betula papyrifera'']) was significantly more rapid than of Pinophyta, conifers (white spruce, black spruce [''Picea mariana''], and jack pine [''Pinus banksiana'']) or an evergreen angiosperm (Labrador tea) growing on a fertilized Brunisol. These metabolic and visible injury responses seemed to be related to the differences in S uptake owing in part to higher gas exchange rates for
deciduous
In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, aft ...
species than for Pinophyta, conifers. Conifers growing in oil sands tailings responded to SO2 with a significantly more rapid decrease in NAR compared with those growing in the Brunisol, perhaps because of predisposing toxic material in the tailings. However, Sulfur, sulphur uptake and visible symptom development did not differ between conifers growing on the 2 substrates.
Acidification of precipitation by anthropogenic, acid-forming emissions has been associated with damage to vegetation and reduced forest productivity, but 2-year-old white spruce that were subjected to simulated acid rain (at PH indicator, pH 4.6, 3.6, and 2.6) applied weekly for 7 weeks incurred no statistically significant (P 0.05) reduction in growth during the experiment compared with the background control (pH 5.6) (Abouguendia and Baschak 1987).Abouguendia, Z.M.; Baschak, L.A. 1987. "Response of two western Canadian conifers to simulated acidic precipitation". ''Water, Air and Soil Pollution'' 33:15–22. However, symptoms of injury were observed in all treatments, the number of plants and the number of needles affected increased with increasing rain acidity and with time. Scherbatskoy and Klein (1983)Scherbatskoy, T.; Klein, R.M. 1983. "Response of spruce Picea glauca and birch Betula alleghaniensis foliage to leaching by acidic mists". ''J. Environ. Qual.'' 12:189–95. found no significant effect of chlorophyll concentration in white spruce at pH 4.3 and 2.8, but Abouguendia and Baschak (1987) found a significant reduction in white spruce at pH 2.6, while the foliar sulphur content significantly greater at pH 2.6 than any of the other treatments.
Protection
The taiga stores enormous quantities of carbon, more than the world's temperate and tropical forests combined, much of it in wetlands and peatland. In fact, current estimates place boreal forests as storing twice as much carbon per unit area as tropical forests. Wildfires could use up a significant part of the global carbon budget, so fire management at about 12 dollars per tonne of carbon not released is very cheap compared to the social cost of carbon.
Some nations are discussing protecting areas of the taiga by prohibiting logging, mining, fossil fuel exploration, oil and gas production, and other forms of development. Responding to a letter signed by 1,500 scientists calling on political leaders to protect at least half of the boreal forest, two Canadian provincial governments, Ontario and Quebec, offered election promises to discuss measures in 2008 that might eventually classify at least half of their northern boreal forest as "protected". Although both provinces admitted it would take decades to plan, working with Aboriginal and local communities and ultimately mapping out precise boundaries of the areas off-limits to development, the measures were touted to create some of the largest protected areas networks in the world once completed. Since then, however, very little action has been taken.
For instance, in February 2010 the Canadian government established limited protection for 13,000 square kilometres of boreal forest by creating a new 10,700-square-kilometre park reserve in the Mealy Mountains area of eastern Canada and a 3,000-square-kilometre waterway provincial park that follows alongside the Eagle River from headwaters to sea.
Natural disturbance
One of the biggest areas of research and a topic still full of unsolved questions is the recurring disturbance of fire and the role it plays in propagating the lichen woodland.Kurkowski, 1911. The phenomenon of wildfire by lightning strike is the primary determinant of understory vegetation, and because of this, it is considered to be the predominant force behind community and ecosystem properties in the lichen woodland.Nilsson, 421. The significance of fire is clearly evident when one considers that understory vegetation influences tree seedling germination in the short term and decomposition of biomass and nutrient availability in the long term. The recurrent cycle of large, damaging fire occurs approximately every 70 to 100 years. Understanding the dynamics of this ecosystem is entangled with discovering the successional paths that the vegetation exhibits after a fire. Trees, shrubs, and lichens all recover from fire-induced damage through vegetative reproduction as well as invasion by propagules.Johnson, 200 Seeds that have fallen and become buried provide little help in re-establishment of a species. The reappearance of lichens is reasoned to occur because of varying conditions and light/nutrient availability in each different microstate. Several different studies have been done that have led to the formation of the theory that post-fire development can be propagated by any of four pathways: self replacement, species-dominance relay, species replacement, or gap-phase self replacement. Self-replacement is simply the re-establishment of the pre-fire dominant species. Species-dominance relay is a sequential attempt of tree species to establish dominance in the canopy. Species replacement is when fires occur in sufficient frequency to interrupt species dominance relay. Gap-Phase Self-Replacement is the least common and so far has only been documented in Western Canada. It is a self replacement of the surviving species into the canopy gaps after a fire kills another species. The particular pathway taken after fire disturbance depends on how the landscape is able to support trees as well as fire frequency. Fire frequency has a large role in shaping the original inception of the lower forest line of the lichen woodland taiga.
It has been hypothesized by Serge Payette that the spruce-moss forest ecosystem was changed into the lichen woodland biome due to the initiation of two compounded strong disturbances: large fire and the appearance and attack of the spruce budworm.Payette, 289. The spruce budworm is a deadly insect to the spruce populations in the southern regions of the taiga. J.P. Jasinski confirmed this theory five years later stating, "Their [lichen woodlands] persistence, along with their previous moss forest histories and current occurrence adjacent to closed moss forests, indicate that they are an alternative stable state to the spruce–moss forests".Jasinski, 561.
Taiga ecoregions
See also
*Birds of North American boreal forests
*Boreal Forest Conservation Framework
*Drunken treeseffect of global warming on the taiga
*Intact forest landscape
*Agafia Lykov
*Scandinavian and Russian taiga
*Success of fire suppression in northern forests
*Taiga Rescue Network, Taiga Rescue Network (TRN)