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89-591: The area is bounded on the north by the forests of Siberia , on the east by mountains along the Pacific coast, on the southeast by a small area of agricultural China , on the south by the Tibetan plateau and on the west by the mountains along the former Sino-Soviet border . Between these mountains and Siberia the so-called Dzungarian Gate opens out onto the vast Kazakh steppe to the west. The area has three parts: Manchuria , Mongolia and Dzungaria . The core of

178-574: A Russian population. There was a massive migration of Han Chinese into Manchuria and Inner Mongolia which socially removed these areas from the steppe and attached them to China. When the Manchu dynasty fell in 1912 the Mongols claimed that they had been subject to the Manchus rather than China and were therefore now independent. This Russian-backed independence may have prevented Chinese immigration into

267-615: A discussion regarding the accuracy and resolution of dates for events of the 2nd millennium BC in the Near East. Spending much of their energies in trying to recuperate from the chaotic situation that existed at the turn of the millennium, the most powerful civilizations of the time, Egypt and Mesopotamia , turned their attention to more modest goals. The Pharaohs of the Middle Kingdom of Egypt and their contemporary Kings of Babylon , of Amorite origin, brought governance that

356-412: A fire regime to burn an area equivalent to the total area of an ecosystem is its fire rotation (Heinselman 1973) or fire cycle (Van Wagner 1978). However, as Heinselman (1981) noted, each physiographic site tends to have its own return interval, so that some areas are skipped for long periods, while others might burn two-times or more often during a nominal fire rotation. The dominant fire regime in

445-454: A number of adaptations specifically for survival in harsh taiga winters, although larch, which is extremely cold-tolerant, is deciduous . Taiga trees tend to have shallow roots to take advantage of the thin soils, while many of them seasonally alter their biochemistry to make them more resistant to freezing, called "hardening". The narrow conical shape of northern conifers, and their downward-drooping limbs, also help them shed snow. Because

534-484: A patch of sun; mosses and lichens thrive on the damp ground and on the sides of tree trunks. In comparison with other biomes, however, the taiga has low botanical diversity. Coniferous trees are the dominant plants of the taiga biome. Very few species, in four main genera, are found: the evergreen spruce, fir and pine, and the deciduous larch. In North America, one or two species of fir, and one or two species of spruce, are dominant. Across Scandinavia and western Russia,

623-560: A polar species, some southern herds of muskoxen reside in the taiga of Russia's Far East and North America. The Amur -Kamchatka region of far eastern Russia also supports the snow sheep , the Russian relative of the American bighorn sheep , wild boar , and long-tailed goral . The largest animal in the taiga is the wood bison of northern Canada/Alaska; additionally, some numbers of the American plains bison have been introduced into

712-408: A relatively small variety of highly specialized and adapted animals, due to the harshness of the climate. Canada's boreal forest includes 85 species of mammals , 130 species of fish, and an estimated 32,000 species of insects . Insects play a critical role as pollinators , decomposers , and as a part of the food web. Many nesting birds, rodents, and small carnivorous mammals rely on them for food in

801-522: A transition from Old Egyptian to Middle Egyptian . As the most used written form of the Ancient Egyptian language, it is frequently (incorrectly) referred to simply as " Hieroglyphics ". The earliest attested Indo-European language , the Hittite language , first appears in cuneiform in the 16th century BC ( Anitta text ), before disappearing from records in the 13th century BC. Hittite is

890-412: A warmer climate. The mature boreal forest pattern in the south shows balsam fir dominant on well-drained sites in eastern Canada changing centrally and westward to a prominence of white spruce , with black spruce and tamarack forming the forests on peats, and with jack pine usually present on dry sites except in the extreme east, where it is absent. The effects of fires are inextricably woven into

979-857: Is a relatively recent phenomenon, having only existed for the last 12,000 years since the beginning of the Holocene epoch, covering land that had been mammoth steppe or under the Scandinavian Ice Sheet in Eurasia and under the Laurentide Ice Sheet in North America during the Late Pleistocene . Although at high elevations taiga grades into alpine tundra through Krummholz , it is not exclusively an alpine biome, and unlike subalpine forest , much of taiga

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1068-581: Is a threat to taiga, and how the carbon dioxide absorbed or emitted should be treated by carbon accounting is controversial. Taiga covers 17 million square kilometres (6.6 million square miles) or 11.5% of the Earth's land area, second only to deserts and xeric shrublands . The largest areas are located in Russia and Canada. In Sweden taiga is associated with the Norrland terrain . After

1157-409: Is found in the smaller areas with oceanic influences; in coastal areas of Scandinavia and Finland, the growing season of the closed boreal forest can be 145–180 days. The shortest growing season is found at the northern taiga–tundra ecotone , where the northern taiga forest no longer can grow and the tundra dominates the landscape when the growing season is down to 50–70 days, and the 24-hr average of

1246-427: Is further evidence pointing to a long and intimate association with fire. Seven of the ten most common trees in the boreal forest— jack pine , lodgepole pine , aspen , balsam poplar ( Populus balsamifera ), paper birch , tamarack , black spruce – can be classed as pioneers in their adaptations for rapid invasion of open areas. White spruce shows some pioneering abilities, too, but is less able than black spruce and

1335-554: Is home to many types of berries . Some species are confined to the southern and middle closed-boreal forest (such as wild strawberry and partridgeberry ); others grow in most areas of the taiga (such as cranberry and cloudberry ). Some berries can grow in both the taiga and the lower arctic (southern regions) tundra, such as bilberry , bunchberry and lingonberry . The forests of the taiga are largely coniferous , dominated by larch , spruce , fir and pine . The woodland mix varies according to geography and climate; for example,

1424-588: 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 in referring to more southerly regions, while "taiga" is used to describe the more northern, barren areas approaching the tree line and the tundra . Hoffman (1958) discusses the origin of this differential use in North America and how this differentiation distorts established Russian usage. Climate change

1513-416: Is not a limiting factor, the ground freezes during the winter months and plant roots are unable to absorb water, so desiccation can be a severe problem in late winter for evergreens. Although the taiga is dominated by coniferous forests, some broadleaf trees also occur, including birch , aspen , willow , and rowan . Many smaller herbaceous plants, such as ferns and occasionally ramps grow closer to

1602-835: The Aegean and the rise of the Hittite Empire . The end of the millennium sees the Bronze Age collapse and the transition to the Iron Age . Other regions of the world are still in the prehistoric period. In Europe, the Beaker culture introduces the Bronze Age , presumably associated with Indo-European expansion . The Indo-Iranian expansion reaches the Iranian plateau and onto the Indian subcontinent ( Vedic India ), propagating

1691-547: The Bering land bridge , a number of animal and plant species , more animals than plants, were able to colonize both land masses, and are globally-distributed throughout the taiga biome (see Circumboreal Region ). Others differ regionally, typically with each genus having several distinct species, each occupying different regions of the taiga. Taigas also have some small-leaved deciduous trees, like birch , alder , willow , and poplar . These grow mostly in areas further south of

1780-558: The Bronze Age early in the 2nd millennium. The desiccation of the Sahara is complete. Neolithisation of Sub-Saharan Africa is initiated via expansion from the dried Sahara, reaching West and East Africa. Later in the 2nd millennium, pastoralism and iron metallurgy spread to Central Africa via the Bantu migration . In the history of the Egyptian language , the early 2nd millennium saw

1869-485: The Dfd and Dwd climate zones continuous permafrost occurs and restricts growth to very shallow-rooted trees like Siberian larch . The growing season , when the vegetation in the taiga comes alive, is usually slightly longer than the climatic definition of summer as the plants of the boreal biome have a lower temperature threshold to trigger growth than other plants. Some sources claim 130 days growing season as typical for

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1958-699: The Eastern Canadian forests ecoregion (of the higher elevations of the Laurentian Mountains and the northern Appalachian Mountains ) in Canada is dominated by balsam fir Abies balsamea , while further north, the Eastern Canadian Shield taiga (of northern Quebec and Labrador ) is mostly black spruce Picea mariana and tamarack larch Larix laricina . Evergreen species in the taiga (spruce, fir, and pine) have

2047-498: The Köppen climate classification scheme, meaning that the short summers (24 h average 10 °C (50 °F) or more), although generally warm and humid, only last 1–3 months, while winters, with average temperatures below freezing, last 5–7 months. In Siberian taiga the average temperature of the coldest month is between −6 °C (21 °F) and −50 °C (−58 °F). There are also some much smaller areas grading towards

2136-472: The Minusinsk Basin . A note on ethnonyms: Most of steppe history consists of statements like "in a certain year people A replaced people B." These "peoples" are usually some dynasty, clan or tribe that gained control over its neighbors and became militarily or politically significant. Borders were ill-defined and fluctuated, as did the ruler's power. Daily life went on without much regard to whoever

2225-680: The Scots pine is a common component of the taiga, while taiga of the Russian Far East and Mongolia is dominated by larch . Rich in spruce and Scots pine (in the western Siberian plain), the taiga is dominated by larch in Eastern Siberia, before returning to its original floristic richness on the Pacific shores. Two deciduous trees mingle throughout southern Siberia: birch and Populus tremula . The boreal forest/taiga supports

2314-419: The golden eagle , rough-legged buzzard (also known as the rough-legged hawk), Steller's sea eagle (in coastal northeastern Russia-Japan), great gray owl , snowy owl , barred owl , great horned owl , crow and raven . The only other viable adaptation is seed-eating birds, which include several species of grouse , capercaillie and crossbills . Fire has been one of the most important factors shaping

2403-517: The lowest reliably recorded temperatures in the Northern Hemisphere were recorded in the taiga of northeastern Russia. Taiga has a subarctic climate with very large temperature range between seasons. −20 °C (−4 °F) would be a typical winter day temperature and 18 °C (64 °F) an average summer day, but the long, cold winter is the dominant feature. This climate is classified as Dfc , Dwc , Dsc , Dfd and Dwd in

2492-445: The middle boreal (closed forest), and the southern boreal , a closed-canopy, boreal forest with some scattered temperate, deciduous trees among the conifers. Commonly seen are species such as maple, elm and oak. This southern boreal forest experiences the longest and warmest growing season of the biome. In some regions, including Scandinavia and western Russia, this subzone is commonly used for agricultural purposes. The boreal forest

2581-498: The peatlands . During the last quarter of the twentieth century, the zone of latitude occupied by the boreal forest experienced some of the greatest temperature increases on Earth. Winter temperatures have increased more than summer temperatures. In summer, the daily low temperature has increased more than the daily high temperature. The number of days with extremely cold temperatures (e.g., −20 to −40 °C; −4 to −40 °F) has decreased irregularly but systematically in nearly all

2670-503: 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. Second millennium BC The 2nd millennium BC spanned

2759-517: The 2nd millennium BC several regional powers competed relentlessly for hegemony, many developments occurred: there was new emphasis on grandiose architecture, new clothing fashions, vivid diplomatic correspondence on clay tablets , renewed economic exchanges, and the New Kingdom of Egypt played the role of the main superpower . Among the great states of the time, only Babylon refrained from taking part in battles, mainly due to its new position as

History of the eastern steppe - Misplaced Pages Continue

2848-620: The Chinese called Rong (west), Beidi (north), Donghu (east) and other names. In 221 BC, China proper was unified by the Qin dynasty and after a brief civil war, more permanently by the Han dynasty (206 BC – 220 AD). About 209 BC the steppe tribes were united by the Xiongnu . The two unifications were connected in that the nomads had to unite to protect themselves from the powerful Han dynasty and

2937-466: The Cordilleran region, fire is most frequent in the valley bottoms, decreasing upward, as shown by a mosaic of young pioneer pine and broadleaf stands below, and older spruce–fir on the slopes above. Without fire, the boreal forest would become more and more homogeneous, with the long-lived white spruce gradually replacing pine, aspen, balsam poplar, and birch, and perhaps even black spruce, except on

3026-685: The Gansu corridor into the Tarim Basin. When the nomads were strong they would try to control, tax or loot the Gansu-Tarim region. On the northern edge can be noted the forest-steppe of north Manchuria and west of that the thinly-populated mountains of Transbaikalia . Around Lake Baikal the forest and steppe peoples have tended to blend, producing the modern Buryats . West of that is the Altai-Sayan region noted for its metalwork, especially

3115-590: The Hudson Bay area), chum salmon , Siberian taimen , lenok and lake chub . The taiga is mainly home to a number of large herbivorous mammals , such as Alces alces ( moose ), and a few subspecies of Rangifer tarandus ( reindeer in Eurasia; caribou in North America). Some areas of the more southern closed boreal forest have populations of other Cervidae species, such as the maral , elk , Sitka black-tailed deer , and roe deer . While normally

3204-465: The Pacific. The Manchurian steppe merges northward to a deciduous forest-steppe and then the coniferous forest of Siberia. To the south it merges into agricultural China. In the west Dzungaria or northern Xinjiang is a westward extension of Mongolia. To the west of that the Dzungarian Gate leads to the extensive steppes of Kazakhstan, particularly the region of Jetysu . In the southeast is

3293-541: The Roman Empire. As the Han dynasty declined, the Tarim Basin experienced complex shifts of power between the Han, Xiongnu remnants and local rulers. In the 19th century Western imperialism and industrialism began to impact eastern Asia. Steppe nomadism and many traditional Chinese institutions gradually became obsolete, both economically and militarily. In 1860 Russia annexed north and east Manchuria which soon acquired

3382-441: The Russian far-east, as part of the taiga regeneration project called Pleistocene Park , in addition to Przewalski's horse . Small mammals of the taiga biome include rodent species such as the beaver , squirrel , chipmunk , marmot , lemming , North American porcupine and vole , as well as a small number of lagomorph species, such as the pika , snowshoe hare and mountain hare . These species have adapted to survive

3471-839: The Xiongnu ruler could strengthen himself with Han tribute. In the east, the Xiongnu conquered the Donghu in Manchuria and in the west they drove the Wusun and Yuezhi westward. The Wusun soon disappeared, but the Yuezhi later had a great career as the Kushans of Afghanistan. After about 75 years of internal consolidation and external tribute, the Emperor Wu of Han adopted a forward policy . Zhang Qian went west (138-125 BC) and returned with

3560-721: The agricultural area of the North China Plain , roughly around Beijing and southward. West of that are the mountains of Shanxi (the name means "western mountains"). West of the mountains is the Ordos Loop of the Yellow River . On the southern side of the Ordos country is the Wei River valley which was long a center of Chinese civilization. The northern Ordos region is semi-desert and part of Inner Mongolia. The area

3649-557: The area is Mongolia, not only the Outer Mongolia that is seen on maps but also Inner Mongolia and much of Gansu which are now part of China. The Gobi Desert or semi-desert separates Outer and Inner Mongolia. The best grazing lands are in the north around such places as the Orkhon River and Onon Rivers . To the east the steppe extends into "Manchuria" but does not reach the coast because of mountains and moisture from

History of the eastern steppe - Misplaced Pages Continue

3738-401: The area. In recent decades there has been a significant Han migration into Xinjiang. Taiga Taiga or tayga ( / ˈ t aɪ ɡ ə / TY -gə ; Russian : тайга́ , IPA: [tɐjˈɡa] ), also known as boreal forest or snow forest , is a biome characterized by coniferous forests consisting mostly of pines , spruces , and larches . The taiga or boreal forest is

3827-564: The best known and the most studied language of the extinct Anatolian branch of Indo-European languages. The first Northwest Semitic language , Ugaritic , is attested in the 14th century BC. The first fully phonemic script Proto-Canaanite developed from Egyptian hieroglyphs, becoming the Phoenician alphabet by 1200 BC. The Phoenician alphabet was spread throughout the Mediterranean by Phoenician maritime traders and became one of

3916-440: The boreal forest is high-intensity crown fires or severe surface fires of very large size, often more than 10,000 ha (100 km ), and sometimes more than 400,000 ha (4000 km ). Such fires kill entire stands. Fire rotations in the drier regions of western Canada and Alaska average 50–100 years, shorter than in the moister climates of eastern Canada, where they may average 200 years or more. Fire cycles also tend to be long near

4005-471: The boreal forest, typically with abrupt, irregular boundaries circumscribing homogenous stands, is indirect but compelling testimony to the role of fire in shaping the forest. The fact is that most boreal forest stands are less than 100 years old, and only in the rather few areas that have escaped burning are there stands of white spruce older than 250 years. The prevalence of fire-adaptive morphologic and reproductive characteristics of many boreal plant species

4094-527: The boreal region, allowing better survival for tree-damaging insects. In Fairbanks, Alaska , the length of the frost-free season has increased from 60 to 90 days in the early twentieth century to about 120 days a century later. It has been hypothesized that the boreal environments have only a few states which are stable in the long term - a treeless tundra/steppe, a forest with >75% tree cover and an open woodland with ~20% and ~45% tree cover. Thus, continued climate change would be able to force at least some of

4183-526: The composition and development of boreal forest stands; it is the dominant stand-renewing disturbance through much of the Canadian boreal forest. The fire history that characterizes an ecosystem is its fire regime , which has 3 elements: (1) fire type and intensity (e.g., crown fires, severe surface fires, and light surface fires), (2) size of typical fires of significance, and (3) frequency or return intervals for specific land units. The average time within

4272-487: The dark winters, depending on latitude. The areas of the taiga inside the Arctic Circle have midnight sun in mid-summer and polar night in mid-winter. The taiga experiences relatively low precipitation throughout the year (generally 200–750 mm (7.9–29.5 in) annually, 1,000 mm (39 in) in some areas), primarily as rain during the summer months, but also as snow or fog . Snow may remain on

4361-539: The dense vegetation growth including large trees. This explains the striking difference in biomass per square metre between the Taiga and the Steppe biomes, (in warmer climates), where evapotranspiration exceeds precipitation, restricting vegetation to mostly grasses. In general, taiga grows to the south of the 10 °C (50 °F) July isotherm , occasionally as far north as the 9 °C (48 °F) July isotherm, with

4450-459: The ease with which plants can use its nutrients. The relative lack of deciduous trees, which drop huge volumes of leaves annually, and grazing animals, which contribute significant manure, are also factors. The diversity of soil organisms in the boreal forest is high, comparable to the tropical rainforest . Fallen leaves and moss can remain on the forest floor for a long time in the cool, moist climate, which limits their organic contribution to

4539-478: The edges. The Tarim is desert rather than steppe but interacted with the steppe in various ways. At the west end of the Tarim Basin passes lead over the mountains south to India and west to central Asia , Persia and Europe . The Gansu-Tarim route was the main axis of the Silk Road that connected China with the rest of the world. When Chinese dynasties were strong they would often extend a finger of power along

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4628-521: The end of the 2nd millennium BC, new waves of barbarians , this time riding on horseback, wholly destroyed the Bronze Age world, and were to be followed by waves of social changes that marked the beginning of different times. Also contributing to the changes were the Sea Peoples , ship-faring raiders of the Mediterranean. Europe is still entirely within the prehistoric era; much of Europe enters

4717-657: The first good reports of the Western Regions . During the Han-Xiongnu Wars the southern Xiongnu in Inner Mongolia were subjugated and the northern Xiongnu were driven to northern Mongolia where they were broken up around 89 AD. The Han gained control of the Gansu Corridor and the Tarim Basin with some influence westward. This opened the Silk Road and led to the appearance of Chinese silk in

4806-459: The forest history of an area 280 km north of the then-current tree line at Ennadai Lake, District Keewatin, Northwest Territories. Two lines of evidence support the thesis that fire has always been an integral factor in the boreal forest: (1) direct, eye-witness accounts and forest-fire statistics, and (2) indirect, circumstantial evidence based on the effects of fire, as well as on persisting indicators. The patchwork mosaic of forest stands in

4895-404: The ground for as long as nine months in the northernmost extensions of the taiga biome. The fog, especially predominant in low-lying areas during and after the thawing of frozen Arctic seas, stops sunshine from getting through to plants even during the long summer days. As evaporation is consequently low for most of the year, annual precipitation exceeds evaporation, and is sufficient to sustain

4984-519: The ground. Periodic stand-replacing wildfires (with return times of between 20 and 200 years) clear out the tree canopies, allowing sunlight to invigorate new growth on the forest floor. For some species, wildfires are a necessary part of the life cycle in the taiga; some, e.g. jack pine have cones which only open to release their seed after a fire, dispersing their seeds onto the newly cleared ground; certain species of fungi (such as morels ) are also known to do this. Grasses grow wherever they can find

5073-493: The harsh winters in their native ranges. Some larger mammals, such as bears , eat heartily during the summer in order to gain weight, and then go into hibernation during the winter. Other animals have adapted layers of fur or feathers to insulate them from the cold. Predatory mammals of the taiga must be adapted to travel long distances in search of scattered prey, or be able to supplement their diet with vegetation or other forms of food (such as raccoons ). Mammalian predators of

5162-486: The interior of the continents, with the driest climates, the boreal forests might grade into temperate grassland . There are two major types of taiga. The southern part is the closed canopy forest , consisting of many closely-spaced trees and mossy groundcover. In clearings in the forest, shrubs and wildflowers are common, such as the fireweed and lupine . The other type is the lichen woodland or sparse taiga , with trees that are farther-spaced and lichen groundcover;

5251-503: The island of Hokkaidō ). The principal 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; Scandinavian and Finnish taiga consists of a mix of spruce , pines and birch ; Russian taiga has spruces, pines and larches depending on the region; and the Eastern Siberian taiga is a vast larch forest. Taiga in its current form

5340-425: The latter is common in the northernmost taiga. In the northernmost taiga, the forest cover is not only more sparse, but often stunted in growth form; moreover, ice-pruned , asymmetric black spruce (in North America) are often seen, with diminished foliage on the windward side. In Canada, Scandinavia and Finland, the boreal forest is usually divided into three subzones: The high boreal (northern boreal/taiga zone),

5429-474: The most extreme winter weather. The Dahurian larch tolerates the coldest winters of the Northern Hemisphere, in eastern Siberia. The very southernmost parts of the taiga may have trees such as oak , maple , elm and lime scattered among the conifers, and there is usually a gradual transition into a temperate, mixed forest, such as the eastern forest-boreal transition of eastern Canada. In

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5518-578: The most widely used writing systems in the world, and the parent of virtually all alphabetic writing systems. The Phoenician language is also the first Canaanite language , the Northwest Semitic languages spoken by the ancient peoples of the Canaan region: the Israelites , Phoenicians , Amorites , Ammonites , Moabites and Edomites . Mycenaean Greek , the most ancient attested form of

5607-491: The oceanic Cfc climate with milder winters, whilst the extreme south and (in Eurasia) west of the taiga reaches into humid continental climates ( Dfb , Dwb ) with longer summers. According to some sources, the boreal forest grades into a temperate mixed forest when mean annual temperature reaches about 3 °C (37 °F). Discontinuous permafrost is found in areas with mean annual temperature below freezing, whilst in

5696-406: The patterns of vegetation on the landscape, which in the east favour black spruce, paper birch, and jack pine over balsam fir, and in the west give the advantage to aspen, jack pine, black spruce, and birch over white spruce. Many investigators have reported the ubiquity of charcoal under the forest floor and in the upper soil profile. Charcoal in soils provided Bryson et al. (1965) with clues about

5785-446: The permanent ice caps and tundra , taiga is the terrestrial biome with the lowest annual average temperatures, with mean annual temperature generally varying from −5 to 5 °C (23 to 41 °F). Extreme winter minimums in the northern taiga are typically lower than those of the tundra. There are taiga areas of eastern Siberia and interior Alaska- Yukon where the mean annual temperature reaches down to −10 °C (14 °F), and

5874-471: The pines to disperse seed at all seasons. Only balsam fir and alpine fir seem to be poorly adapted to reproduce after fire, as their cones disintegrate at maturity, leaving no seed in the crowns. The oldest forests in the northwest boreal region, some older than 300 years, are of white spruce occurring as pure stands on moist floodplains . Here, the frequency of fire is much less than on adjacent uplands dominated by pine, black spruce and aspen. In contrast, in

5963-423: The presently existing taiga forests into one of the two woodland states or even into a treeless steppe - but it could also shift tundra areas into woodland or forest states as they warm and become more suitable for tree growth. In keeping with this hypothesis, several studies published in the early 2010s found that there was already a substantial drought-induced tree loss in the western Canadian boreal forests since

6052-416: The soil. Acids from evergreen needles further leach the soil, creating spodosol , also known as podzol , and the acidic forest floor often has only lichens and some mosses growing on it. In clearings in the forest and in areas with more boreal deciduous trees, there are more herbs and berries growing, and soils are consequently deeper. Since North America and Eurasia were originally connected by

6141-434: The southern limit more variable. Depending on rainfall, and taiga may be replaced by forest steppe south of the 15 °C (59 °F) July isotherm where rainfall is very low, but more typically extends south to the 18 °C (64 °F) July isotherm, and locally where rainfall is higher, such as in eastern Siberia and adjacent Outer Manchuria , south to the 20 °C (68 °F) July isotherm. In these warmer areas

6230-542: The summer months. The cold winters and short summers make the taiga a challenging biome for reptiles and amphibians , which depend on environmental conditions to regulate their body temperatures. There are only a few species in the boreal forest, including red-sided garter snake , common European adder , blue-spotted salamander , northern two-lined salamander , Siberian salamander , wood frog , northern leopard frog , boreal chorus frog , American toad , and Canadian toad . Most hibernate underground in winter. Fish of

6319-512: The sun is low in the horizon for most of the year, it is difficult for plants to generate energy from photosynthesis . Pine, spruce and fir do not lose their leaves seasonally and are able to photosynthesize with their older leaves in late winter and spring when light is good but temperatures are still too low for new growth to commence. The adaptation of evergreen needles limits the water lost due to transpiration and their dark green color increases their absorption of sunlight. Although precipitation

6408-580: The taiga has higher species diversity, with more warmth-loving species such as Korean pine , Jezo spruce , and Manchurian fir , and merges gradually into mixed temperate forest or, more locally (on the Pacific Ocean coasts of North America and Asia), into coniferous temperate rainforests where oak and hornbeam appear and join the conifers, birch and Populus tremula . The area currently classified as taiga in Europe and North America (except Alaska)

6497-531: The taiga include Canada lynx , Eurasian lynx , stoat , Siberian weasel , least weasel , sable , American marten , North American river otter , European otter , American mink , wolverine , Asian badger , fisher , timber wolf , Mongolian wolf , coyote , red fox , Arctic fox , grizzly bear , American black bear , Asiatic black bear , Ussuri brown bear , polar bear (only small areas of northern taiga), Siberian tiger , and Amur leopard . More than 300 species of birds have their nesting grounds in

6586-401: The taiga must be able to withstand cold water conditions and be able to adapt to life under ice-covered water. Species in the taiga include Alaska blackfish , northern pike , walleye , longnose sucker , white sucker , various species of cisco , lake whitefish , round whitefish , pygmy whitefish , Arctic lamprey , various grayling species, brook trout (including sea-run brook trout in

6675-809: The taiga. In Canada and Scandinavia, the growing season is often estimated by using the period of the year when the 24-hour average temperature is +5 °C (41 °F) or more. For the Taiga Plains in Canada, growing season varies from 80 to 150 days, and in the Taiga Shield from 100 to 140 days. Other sources define growing season by frost-free days. Data for locations in southwest Yukon gives 80–120 frost-free days. The closed canopy boreal forest in Kenozersky National Park near Plesetsk , Arkhangelsk Province , Russia, on average has 108 frost-free days. The longest growing season

6764-408: The taiga. Siberian thrush , white-throated sparrow , and black-throated green warbler migrate to this habitat to take advantage of the long summer days and abundance of insects found around the numerous bogs and lakes. Of the 300 species of birds that summer in the taiga, only 30 stay for the winter. These are either carrion -feeding or large raptors that can take live mammal prey, such as

6853-467: The tree line in the subarctic spruce-lichen woodlands. The longest cycles, possibly 300 years, probably occur in the western boreal in floodplain white spruce. Amiro et al. (2001) calculated the mean fire cycle for the period 1980 to 1999 in the Canadian boreal forest (including taiga) at 126 years. Increased fire activity has been predicted for western Canada, but parts of eastern Canada may experience less fire in future because of greater precipitation in

6942-541: The use of the chariot . Mesoamerica enters the Pre-Classic ( Olmec ) period. North America is in the late Archaic stage . In Maritime Southeast Asia, the Austronesian expansion reaches Micronesia . In Sub-Saharan Africa , the Bantu expansion begins. World population rose steadily, possibly surpassing the 100 million mark for the first time. See the article on chronology of the ancient Near East for

7031-404: The warmest month of the year usually is 10 °C (50 °F) or less. High latitudes mean that the sun does not rise far above the horizon, and less solar energy is received than further south. But the high latitude also ensures very long summer days, as the sun stays above the horizon nearly 20 hours each day, or up to 24 hours, with only around 6 hours of daylight, or none, occurring in

7120-559: The world's largest land biome . In North America, it covers most of inland Canada , Alaska , and parts of the northern contiguous United States. In Eurasia , it covers most of Sweden , Finland , much of Russia from Karelia in the west to the Pacific Ocean (including much of Siberia ), much of Norway and Estonia , some of the Scottish Highlands , some lowland/coastal areas of Iceland , and areas of northern Kazakhstan , northern Mongolia , and northern Japan (on

7209-470: The world's religious and intellectual capital. The Bronze Age civilization at its final period of time, displayed all its characteristic social traits: low level of urbanization, small cities centered on temples or royal palaces, strict separation of classes between an illiterate mass of peasants and craftsmen, and a powerful military elite , knowledge of writing and education reserved to a tiny minority of scribes , and pronounced aristocratic life. Near

7298-590: The years 2000 BC to 1001 BC. In the Ancient Near East , it marks the transition from the Middle to the Late Bronze Age . The Ancient Near Eastern cultures are well within the historical era: The first half of the millennium is dominated by the Middle Kingdom of Egypt and Babylonia . The alphabet develops. At the center of the millennium, a new order emerges with Mycenaean Greek dominance of

7387-407: Was recently glaciated . As the glaciers receded they left depressions in the topography that have since filled with water, creating lakes and bogs (especially muskeg soil) found throughout the taiga. Taiga soil tends to be young and poor in nutrients, lacking the deep, organically enriched profile present in temperate deciduous forests. The colder climate hinders development of soil, and

7476-499: Was a fragile situation that crumbled under the pressure of external forces they could not oppose. About a century before the middle of the millennium, bands of Indo-European invaders came from the Central Asian plains and swept through Western Asia and Northeast Africa . They were riding fast two-wheeled chariots powered by horses , a system of weaponry developed earlier in the context of plains warfare. This tool of war

7565-408: Was in power. "Replacement" usually means a mere change of ruling group, but sometimes involved a genuine folk migration or change in language or religion. Since historical records depend on scattered reports from neighboring literate societies, there is substantial uncertainty especially in the early period. Civilization emerged in north China in the second millennium BC . At this time the Tarim Basin

7654-461: Was inhabited by people of European appearance who probably spoke an Indo-European language ( Tocharian ). They may have introduced the chariot and bronze-working into China. The later Yuezhi in the Gansu corridor may have also been Tocharian. The origin of steppe pastoral nomadism is not well understood. Mounted archery began in the west and reached east Asia some time before 307 BC . The steppes were inhabited by various disunited tribes that

7743-474: Was largely popular and approved of among their subjects, and favoured elegant art and architecture. Farther east, the Indus Valley civilization was in a period of decline, possibly as a result of intense, ruinous flooding. Egypt and Babylonia's military tactics were still based on foot soldiers transporting their equipment on donkeys . Combined with a weak economy and difficulty in maintaining order, this

7832-440: Was often disputed between agricultural China and the steppe nomads. West of that is the long and narrow Gansu Corridor . It is bounded on the south by the high and desolate Tibetan plateau and on the north by the grasslands of Mongolia. Along it is a chain of oases which form a natural caravan route from China westward. At the west end of the Gansu corridor is the oval Tarim Basin with its central desert and ring of oases around

7921-569: Was unknown among the classical civilizations. Egypt and Babylonia's foot soldiers were unable to defend against the invaders: in 1630 BC , the Hyksos swept into the Nile Delta , and in 1595 BC , the Hittites swept into Mesopotamia . The people in place were quick to adapt to the new tactics, and a new international situation resulted from the change. Though during most of the second half of

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