Yellow River

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Upper reach landscape, Yellow River on the Qinghai Plateau. CC-3.0

The Yellow River rises in the Bayan Har and Kunlun Mountains, drains a portion of the Tibetan Plateau and the Ordos Desert, flows across the North China and Huang He Plains, and discharges to the Bohai Sea. At a length of 5465 kilometres, it is the world's sixth longest river. Also known as Huang He, the Yellow River is the locus of much of ancient Chinese civilisation, and a major basin containing the western termini of the famous Silk Road trading routes that provided the first connection to Europe.

Liujiaxia-damyellowrivervmenkov.jpg Liujaxia Dam, Yellow River, Gansu. Source: V.Menkov Beginning in the 1960s numerous hydroelectric dams have been constructed on the Yellow River, leading to massive ecological damage; most of the dam construction began after the Great Leap Forward program of the Communist government, and many of the projects were characterised by massive dislocation of native people, high reservoir siltation and in many cases dam failures. Even earlier, the instinct to control flooding on the North China Plain has led to widespread levee construction, which activity has often resulted in exacerbation of larger flood events, and also to major changes in the lower reach course. The lower basin ecoregion has been heavily degraded by centuries of deforestation and intensive human use.

Headwaters and upper reaches

Yellow-river---andr---holdrinet.jpg Upper reach of the Yellow River near Xunhua, China. Source: André Holdrinet The mainstem of the Yellow River rises in the Bayan Har Mountains; furthermore, the chief tributary, the Wei River, also rises in the Bayan Har Range.

Much of the upper reach of the Yellow River is defined by the Tibetan Plateau, treeless except in the southeastern river valleys, supporting a gamut of alpine vegetation involving alpine meadow, steppe, cold desert and sub-nival cushion plant communities at altitudes ranging from 3500 to almost 6000 metres. The vast arid Tibetan Plateau possesses an alpine landscape of complex zonation with a range of alpine scrub to steppe vegetation to high, cold desert along a transect from southeast to northwest. Trees are present mostly in the riparian areas of the southeastern sector of this Central Tibetan Plateau alpine steppe ecoregion. The city of Xining is the most populated settlement in the upper Yellow River Basin, and was a key trading hub three millennia earlier along the Northern Silk Road.

Cushion plants like Flycatcher Sandwort (Arenaria bryophylla) and Golden Alpine Sandwort (Thylacospermum caespitosa) form dense mats on the high elevation gravels and rocky substrate. While at higher elevations in the more northwestern part of the headwaters, grass cover in these alpine steppe areas is dominated by such taxa as Purple Feathergrass (Stipa purpurea), while hardy tuft forming flora such as Gao Shan Song Cao (Kobresia pygmaea) are in widespread evidence. At somewhat higher elevations Carex moorcroftii replaces the Stipa species, although at the expense of providing the good forage for alpine ungulates as the Stipa. Cushion forbs like Krascheninnikovia compacta also populate the higher elevation locales of the headwaters.

Chiru.jpg Chiru grazing on the Tibetan Plateau. Source: 中国物种信息系统 EOL China Regional Center Several ungulate taxa occur in the alpine steppes of the central Tibetan Plateau. These bovids include Tibetan antelope or Chiru (Pantholops hodgsoni), the only endemic genus of large mammal found in the Tibetan Plateau, a species adapted to moving quickly across expanses of flat to rolling steppe. The rare Tibetan Argali (Ovis ammon hodgsoni) is the largest of the wild sheep in the upper Yellow River Basin.

Wild Yak (Bos grunniens, VU), were historically widespread in the Upper Yellow Basin, but have been exploited to near local extirpation due to hunting by indigenous peoples; they can now only be found in the extreme north of the basin well into the Kunlun Mountains. White-lipped Deer (Cervus albirostris), endemic to the Tibetan Plateau, are found in the alpine steppes including the eastern part of the Changtang eastward into Qinghai.

Xizangalpinetoadtoddpiersoneol.jpg Xizang Alpine Toad, Qinghai. Source: Todd Pierson/CalPhotos/EOL Amphibians found in the upper Yellow River Basin include the Xizang Alpine Toad (Scutiger boulengeri); the High Himalaya Toad (Nanorana parkeri) that occurs in the western headwaters area between 2850 and 5000 metres in altitude.

Reptiles occurring in the Upper Yellow Basin include the limited distribution Ching Hai Toadhead Agama (Phrynocephalus vlangalii). Strauch's Pitviper (Gloydius strauchi) is endemic to the Tibetan Plateau and holds the world altitude record of occurrence among pitvipers, by being found at elevations abover 4000 metres, along with the Mexican taxon Crotalus triseriatus.

Ordos Loop

Yellowriverbasinwithordosloophighlighted.jpg Yellow River Basin, with Ordos Loop in yellow green. Source: Creative Commons The middle reaches of the Yellow River are defined by a geographic region known as the Ordos Loop. The upper part of the loop is defined by the course of the Yellow River Mainstem, initially flowing northeast in the Ordos Loop, thence east, thence south. The upper region within the Ordos Loop consists of the Ordos Desert of Inner Mongolia; The Great Wall of China and Silk Road generally bisect the Ordos Loop with an east-west transect.The lower part of the loop is framed by the Wei River, chief tributary of the Yellow River; The generally east flowing Wei rises in Gansu Province, and is a very important centre of ancient Chinese civilisation.

Redpanda.jpg Red Panda, west-central China @ C.Michael Hogan Notable mammals of the Ordos plateau steppe ecoregion include the Chinese Forest Musk Deer (Moschus berezovskii), an endangered cervid, due to poaching for alleged medicinal musk extract. The Daurian Hedgehog (Mesechinus dauuricus) is also found on the steppe here ranging northeast to the upper Amur Basin. The Near Threatened Groove-toothed Flying Squirrel (Aeretes melanopterus) is endemic to Gansu, Sichuan, Gansu, Hebei and Beijing. The Vulnerable Red Panda (Ailurus fulgens) occurs in the Yellow Basin and ranges from Nepal's Annapurana Mountains to the east in the Qing Ling Mountains of Shaanxi Province. The Vulnerable Marbled Polecat (Vormela peregusna) occurs in the Yellow River Basin and as far west as the Middle East and southeast Europe.

Chinesegiantsalamander.jpg Chinese Giant Salamander. Source: Qijun Wang/Salamanders of China. ed Y.Wu/EoL Amphibians present in the Ordos plateau steppe ecoregion include the Yellow River Basin endemic Endangered Yellow River Frog (Pelophylax tenggerensis), which is found only on the banks of the Yellow River at the edge of the Tengger Desert. Another very restricted range anuran is the Liupan Lazy Toad (Scutiger liupanensis), which has only been found at Liupanshan, Jinyuan County, Ningxia Huizu Zizhiqu Autonomous Region at elevations of 1900 to 2500 metres. Also found in the Ordos is the wider ranging Black-spotted frog (Pelophylax nigromaculatus). The Critically Endangered Chinese Giant Salamander (Andrias davidianus), which is the world's largest salamander at 180 centimetres, is also found here; this amphibian is prized for its meat and its alleged Chinese medicinal properties, so that is continues to be overexploited for its highly prized meat and extracts. The Asiatic Toad (Bufo gargarizans) is also found in the Ordos. A somewhat limited range anuran here is the Gansu Toad (Bufo minshanicus), which is endemic to Gansu, Ningxia, Qinghai and Sichuan provinces at elevation 1700 to 3700 metres.

Reptiles found in the Ordos region include the Caspian Straight-fingered Gecko (Alsophylax pipiens), the Central Asian Pitviper (Gloydius intermedius). The Vulnerable Chinese Soft Shell Turtle (Pelodiscus sinensis) is found here, but is heavily exploited by indigenous peoples for meat. The China endemic Vulnerable Peking Gecko (Gekko swinhonis) occurs in the Yellow Basin west to the Loess Plateau and also in the northern part of the Yangtze Basin.

Wormwoodartemesialeonel-velasquez.jpg Wormwood Sagewort. Source: Leonel Velasquez/EoL Notable birds found in the region are the Near Threatened Cinereous Vulture (Aegypius monachus), the wide-ranging Vulnerable Pallas's Fish Eagle (Haliaeetus leucoryphus) and the Vulnerable Great Bustard (Otis tarda).

Vegetation in the Ordos includes such native vascular plants as the prominent Asian Licorice (Glycyrrhiza uralensis), Wormwood Artemesia (Artemisia campestris). The desiccated streambeds and side channels of the Ordos region often have numerous small mounds of the Nitre-bush (Nitraria roborowskii). White Melilot (Melilotus albus) is an important nectar producer to support honey-bees and other pollinators of the basin.

Huang He Plain

The Huang He Plain is the expansive lowland plain of the Yellow River prior to discharge to the Bohai Sea. Extensive portions of the plain, even those farther inland, manifest soil salinisation. Low hill topography and mountains are evident at the south of the Yellow River, as well as the rocky Shandong Peninsula, which is part of the Huang He Plain. Moreover, the course of the Yellow River has changed dramatically over the last three millennia, partially due to catastrophic flooding, and partly due to human modification of channels, levees and dams.

In the eastern part of the plain, the hills are generally less than 300 meters high. In the western part of the plain, Taishan Peak, at 1524 metres is the point of highest elevation in the lower basin; however, the mountain landforms are here are considerably older than their counterparts in western China, containing metamorphic rocks of the Cambrian Period. This region was densely forested by deciduous broadleaf taxa in prehistoric time, but has long since been greatly degraded, by the burgeoning expansion of the Chinese people during the last several centuries.

Original dominant trees in the lower Yellow River Basin were Sawtooth Oak (Quercus acutissima), Chinese Cork Oak (Quercus variabilis), and Chinese Pistachio (Pistacia chinensis) have been largely removed and have been replaced by secondary forest stands of Japanese Red Pine (Pinus densiflora). The Shandong Peninsula also holds some small populations of Mongolian Oak (Quercus mongolica).

Notable mammals found in this lower part of the Yellow River Basin are the Sika Deer (Cervus nippon), which is also distributed across the Ordos region. Other mammals that occur in the ecoregion are the Near Threatened Birdlike Noctule (Nyctalus aviator); the Vulnerable Chinese Water Deer (Hydropotes inermis); the Endangered Dhole (Cuon alpinus), the Endangered Golden Snub-nosed Monkey (Pygathrix roxellana), although the main range is in the upper basin.

Amphibians occurring in the Huang He Plain mixed forests ecoregion include the Boie's Wart Frog (Fejervarya limnocharis); the Taiwanese Frog (Hoplobatrachus rugulosus); the Swelled Vent Frog (Nanorana quadranus); Manchurian Narrowmouth Toad (Kaloula borealis); Gold-spotted Pond Frog (Pelophylax plancyi). Most of the anuranAn amphibian that has limbs but no tail (includes all frogs and toads)s surviving in this greatly human-modified ecoregion are those taxa that can adapt to breeding in ditches, man made ponds and rice paddies.

Redcrwonedcranechinagroup2-233.jpg Red-crowned Crane, eastern China. @ C.Michael Hogan Reptiles found on the Huang He Plain include the Assam Green Trinket Snake (Gonyosoma frenatum), Cantor's Rat Snake (Ptyas dhumnades), Red Banded Snake (Dinodon rufozonatum), and Shanxi Gecko (Gekko auriverrucosus). In the mouth region of the Yellow River is found the widespread Yellow-bellied Sea Snake (Pelamis platura).

Significant birdlife occurring in the lower Yellow Basin include the Endangered Chinese Merganser (Mergus squamatus), who has been recorded wintering here. The rare and Endangered Red-crowned Crane (Grus japonensis) has a Chinese wintering population, which utilises the Amur Basin and also the Huang He Plain and Korea; there is a separate Japanese population centred in Hokkaido.

Fish species

Chinesepaddlefishcafseol.jpg Juvenile Chinese Paddlefish. Source: Chinese Academy of Fisheries Science/Fishbase/EoL There are very few demersalAn organism living at the bottom of a surface water system. fish taxa in the Yellow River, with most of the fish being benthopelagicOrganisms inhabiting the lower portion of the water column in surface waters.. The Yellow River has only a single near-endemic fish species, the Chinese Paddlefish (Psephurus gladius); this demersal taxon can realise a length of three metres and is found only in the Yellow and Yangtze basins in eastern China. This Critically Endangered species is classified as potamodromousFish that migrate within a river system, and can migrate up to 100 kilometres upstream to spawn; however, it has been observed to occasionally venture into the Bohai Sea as well.

One of the larger demersal fish species found in the upper Yellow Basin is Silurus lanzhouensis, a species considered to have low resilience to population declines. Another native demersal taxon occurring in the Yellow River is the Gudgeon (Gobio rivuloides).

Native benthopelagic fish occurring in the Yellow River Basin include the 32 centimetre (cm) long Yellow River Scaleless Carp (Gymnocypris eckloni); the 16 cm Cuttail Bullhead (Pseudobagrus truncatus); and the 34 cm Northern Bronze Gudgeon (Coreius septentrionalis).

Water quality

The Yellow River has been severely degraded in respect to water pollution, especially since the Communist era, when economic activity has been advanced without corresponding progress in environmental control. Approximately one third of the Yellow River has received excessive quantities of domestic sewage, industrial chemicals, pesticides and nutrient runoff (e.g. nitrate and phosphate) from agriculture; another report filed in 2008 stated that 85 percent of the Yellow River was unsafe for drinking. Overall, it is difficult to get accurate information on water quality of surface water bodies from the present Chinese government, since the state controls media tightly, and has shown little interest in publicizing episodic pollution incidents such as the Songhua River (Amur Basin) benzene spill or the progressive pollution such as long term sediment increases in the Yangtze River from the Three Gorges Dam and related upriver sedimentation.

Wildlife disease

The first incidence of Avian Cholera (Pasteurella multocida) was found in 2007 at the in the Hongjian Nur Lake in the Ordos wetland, when eleven distinct species of wild waterfowl (Anseriformes and Charadriiformes) were discovered dead; this lake is adjacent to the Yellow River. The issue is a particular concern for the Charadriiforme species Relict Gull (Ichthyaetus relictus), a taxon classified as Vulnerable and has a very limited number of breeding grounds: one in Russia, two in Khazakstan and this one lake in China. A previous breeding ground on the Ordos Plateau at Taolimiao-Alashan Nurondha. It is possible that Avian Cholera played a role in the abandonment of the Taolimiao-Alashan Nurondha breeding grounds.

Conservation

There are several protected areas within the Yellow River Basin. In the upper reaches on the Tibetan Plateau the Tibetan Autonomous Region established the Changtang Nature Reserve, a vast region of 247,000 square kilometres; at approximately the size of Arizona, this reserve is the largest in the world outside of the polar regions. It is substantially intactThe condition of an ecological habitat being an undisturbed or natural environment due to the inhospitability to agriculture, even to nomadic pastorism.

In the lower reach lies the small Nansi Hu Nature Reserve, a relict wetland that serves wintering migratory waterfowl; however, as in other preserves in China, the site experiences ongoing degradation by allowed uses of aquaculture, agriculture and overfishing. Another small protected area in the lower Yellow basin is the Rongcheng Nature Reserve, at the eastern tip of the Shandong Peninsula, which is a resting ground for migratory waterfowl including cranes and swans.

Ancient history

Terracottawarriorsxian.jpg Terracotta Warriors lifesize sculpture work, Xi'an. @ C.Michael Hogan Ancient Chinese civilisation flourished in the lower reaches of the Wei and Yellow River Basins, due to the fertile soils that nurtured early agriculture. The Wei River Basin and lower Yellow River Basin along the western North China Plain are major loci of ancient Chinese civilisation, yielding voluminous rich archaeological records from the Bronze Age, through Warring States to Tang Dynasty artefacts. For example, Dating to 210 BC, Terracotta Warriors archaeological site at Xi'an is one of the most extensive examples of funerary art from the ancient world.

References

  • Tania Branigan. 2008. China's Mother River: the Yellow River. The Guardian, United Kingdom (25 November 2008)
  • Mark Elvin & Cuirong Liu (eds.) 1998. Studies in Environment and History: Sediments of Time: Environment and Society in Chinese History Cambridge University Press. ISBN 0-521-56381-X
  • C.Michael Hogan. 2007. Silk Road, North China. The Megalithic Portal, ed. Andy Burnham
  • Li Liu. 2005. The Chinese Neolithic. Cambridge University Press
  • R.W. McDiarmid, J.A. Campbell JA, and T. Touré. 1999. Snake Species of the World: A Taxonomic and Geographic Reference, vol. 1. Herpetologists' League. 511 pp. ISBN 1-893777-00-6
  • Malcolm Moore. 2008. Yellow River, too polluted to drink. The Telegraph, China Edition. Nov. 25, 2008
  • Chengmin Wang, Yanyun Wu, Xiaojun Xing, Guocheng Hu, Jiayin Dai and Hongxuan He. 2007.An Outbreak of Avian Cholera in Wild Waterfowl in Ordos Wetland, Inner Mongolia, China. Journal of Wildlife Diseases. vol. 45 no. 4, pp. 1194-1197

Citation

Hogan, C. (2013). Yellow River. Retrieved from http://editors.eol.org/eoearth/wiki/Yellow_River