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Rangkul Valley Important Bird Area
The Rangkul Valley Important Bird Area ( zh, 郎庫勒河谷重点鸟区) is a 1612 km2 tract of land in eastern Gorno-Badakhshan Autonomous Province in eastern Tajikistan, not far from the border with China. It contains two high altitude lakes and has been identified by BirdLife International as an Important Bird Area (IBA), as well as a Ramsar site. Description The Rangkul Valley is an inter-mountain trough in the eastern Pamir Mountains 60 km north-east of the district centre of Murghab. The central part of the IBA, at an altitude of 3600–4000 m, contains two lakes, Rangkul and Shorkul, which form an endorheic system and are connected by the Izyuk channel. Rangkul is a freshwater lake with an area of 8 km2 and a depth of 6 m. Shorkul is brackish; it has an area of 7 km2. Both lakes freeze in winter and contain no fish, but support numerous invertebrates, including amphipods, beetles and mosquito larvae. Apart from the lakes and their litt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syrrhaptes Tibetanus
The Tibetan sandgrouse (''Syrrhaptes tibetanus'') is a large bird in the sandgrouse family. The genus name ''Syrrhaptes'' is from Ancient Greek ''surrhaptos'', "sewn together" (the feathered toes of this sandgrouse are fused together) and ''tibetanus'' is from the type locality, Tibet. Description The Tibetan sandgrouse is about 30–41 cm long, with a small, pigeon-like head and neck, but sturdy compact body. It has long pointed wings and pin tail. It has an orange face, finely barred grey breast, neck and crown, white belly and black underwings. Male has unspotted buff wing while the female has barred wing coverts, upperparts and upper belly than the male. Juvenile lacks the tail pin, has narrower barrings and has less orange on the face. White belly and dark underwings are distinctions from the related Pallas's sandgrouse, with which its range overlaps. As with that species, its small feet lack a hind toe, and the three front toes are fused together. The upper surfac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The larva's appearance is generally very different from the adult form (''e.g.'' caterpillars and butterflies) including different unique structures and organs that do not occur in the adult form. Their diet may also be considerably different. Larvae are frequently adapted to different environments than adults. For example, some larvae such as tadpoles live almost exclusively in aquatic environments, but can live outside water as adult frogs. By living in a distinct environment, larvae may be given shelter from predators and reduce competition for resources with the adult population. Animals in the larval stage will consume food to fuel their transition into the adult form. In some organisms like polychaetes and barnacles, adults are immobil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saker Falcon
The saker falcon (''Falco cherrug'') is a large species of falcon. This species breeds from central Europe eastwards across the Palearctic to Manchuria. It is mainly migratory except in the southernmost parts of its range, wintering in Ethiopia, the Arabian peninsula, northern Pakistan and western China. The saker falcon is the national bird of Hungary, the United Arab Emirates, and Mongolia. Taxonomy and systematics This species belongs to the close-knit hierofalcon complex. In this group, there is ample evidence for rampant hybridization and incomplete lineage sorting which confounds analyses of DNA sequence data to a massive extent; molecular studies with small sample sizes can simply not be expected to yield reliable conclusions in the entire hierofalcon group. The radiation of the entire living diversity of hierofalcons seems to have taken place in the Eemian interglacial at the start of the Late Pleistocene, a mere 130,000–115,000 years ago; the saker falcon represents ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ruddy Shelduck
The ruddy shelduck (''Tadorna ferruginea''), known in India as the Brahminy duck, is a member of the family Anatidae. It is a distinctive waterfowl, in length with a wingspan of . It has orange-brown body plumage with a paler head, while the tail and the flight feathers in the wings are black, contrasting with the white wing-coverts. It is a migratory bird, wintering in the Indian subcontinent and breeding in southeastern Europe and central Asia, though there are small resident populations in North Africa. It has a loud honking call. The ruddy shelduck mostly inhabits inland water-bodies such as lakes, reservoirs and rivers. The male and female form a lasting pair bond and the nest may be well away from water, in a crevice or hole in a cliff, tree or similar site. A clutch of about eight eggs is laid and is incubated solely by the female for about four weeks. The young are cared for by both parents and fledge about eight weeks after hatching. In central and eastern Asia, pop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bar-headed Goose
The bar-headed goose (''Anser indicus'') is a goose that breeds in Central Asia in colonies of thousands near mountain lakes and winters in South Asia, as far south as peninsular India. It lays three to eight eggs at a time in a ground nest. It is known for the extreme altitudes it reaches when migrating across the Himalayas. Taxonomy The grey goose genus ''Anser'' has no other member indigenous to the Indian region, nor any at all to the Ethiopian, Australian, or Neotropical regions. Ludwig Reichenbach placed the bar-headed goose in the monotypic genus ''Eulabeia'' in 1852, though John Boyd's taxonomy treats both ''Eulabeia'' and the genus ''Chen'' as subgenera of ''Anser''. Description The bird is pale grey and is easily distinguished from any of the other grey geese of the genus ''Anser'' by the black bars on its head. It is also much paler than the other geese in this genus. In flight, its call is a typical goose honking. A mid-sized goose, it measures in total length and w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Himalayan Snowcock
The Himalayan snowcock (''Tetraogallus himalayensis'') is a snowcock in the pheasant family Phasianidae found across the Himalayan ranges and parts of the adjoining Pamir range of Asia. It is found on alpine pastures and on steep rocky cliffs where they will dive down the hill slopes to escape. It overlaps with the slightly smaller Tibetan snowcock in parts of its wide range. The populations from different areas show variations in the colouration and about five subspecies have been designated. They were introduced in the mountains of Nevada in the United States in the 1960s and a wild population has established in the Ruby Mountains. Description The Himalayan snowcock is a large grey partridge-like bird, in length and weighing .''CRC Handbook of Avian Body Masses'' by John B. Dunning Jr. (Editor). CRC Press (1992), . The head pattern has a resemblance to that of the smaller and well marked chukar partridge. The white throat and sides of the head are bordered by chestnut moustac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tibetan Snowcock
The Tibetan snowcock (''Tetraogallus tibetanus'') is a bird in the pheasant family Phasianidae of the order Galliformes, gallinaceous birds. This species is found in high-altitude regions of the Western Himalayas and the Tibetan Plateau, where it overlaps in part with the larger Himalayan snowcock. The head is greyish and there is a white crescent patch behind the eye and underside is white with black stripes. In flight the secondaries show a broad white trailing edge. Description Smaller than Himalayan snowcock, this species has a grey head and neck with a white patch behind the eye and above the dark cheek. Chin, throat and breast are white, with two grey bands on the breast. Grey wing coverts and tertials have a white trim. The secondaries have a broad white trailing edge that forms a wing band. Underparts are white with black streaks on flanks and belly. The tail is rufous brown and the undertail coverts are black. Legs and beaks are reddish. Sexes are similar, but female h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bird Migration
Bird migration is the regular seasonal movement, often north and south along a flyway, between breeding and wintering grounds. Many species of bird migrate. Migration carries high costs in predation and mortality, including from hunting by humans, and is driven primarily by the availability of food. It occurs mainly in the northern hemisphere, where birds are funneled onto specific routes by natural barriers such as the Mediterranean Sea or the Caribbean Sea. Migration of species such as storks, turtle doves, and swallows was recorded as many as 3,000 years ago by Ancient Greek authors, including Homer and Aristotle, and in the Book of Job. More recently, Johannes Leche began recording dates of arrivals of spring migrants in Finland in 1749, and modern scientific studies have used techniques including bird ringing and satellite tracking to trace migrants. Threats to migratory birds have grown with habitat destruction, especially of stopover and wintering sites, as wel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desertification
Desertification is a type of land degradation in drylands in which biological productivity is lost due to natural processes or induced by human activities whereby fertile areas become increasingly arid. It is the spread of arid areas caused by a variety of factors, such as climate change and overexploitation of soil as a result of human activity. Throughout geological history, the development of deserts has occurred naturally. In recent times, the potential influences of human activity, improper land management, deforestation and climate change on desertification is the subject of many scientific investigations. Definitions of words As recently as 2005, considerable controversy existed over the proper definition of the term "desertification." Helmut Geist (2005) identified more than 100 formal definitions. The most widely acceptedGeist (2005)p. 2/ref> of these was that of the Princeton University Dictionary which defined it as "the process of fertile land ''transforming into ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aeolian Processes
Aeolian processes, also spelled eolian, pertain to wind activity in the study of geology and weather and specifically to the wind's ability to shape the surface of the Earth (or other planets). Winds may erode, transport, and deposit materials and are effective agents in regions with sparse vegetation, a lack of soil moisture and a large supply of unconsolidated sediments. Although water is a much more powerful eroding force than wind, aeolian processes are important in arid environments such as deserts. The term is derived from the name of the Greek god Aeolus, the keeper of the winds. Definition and setting ''Aeolian processes'' are those processes of erosion, transport, and deposition of sediments that are caused by wind at or near the surface of the earth. Sediment deposits produced by the action of wind and the sedimentary structures characteristic of these deposits are also described as ''aeolian''. Aeolian processes are most important in areas where there is little or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Overgrazing
Overgrazing occurs when plants are exposed to intensive grazing for extended periods of time, or without sufficient recovery periods. It can be caused by either livestock in poorly managed agricultural applications, game reserves, or nature reserves. It can also be caused by immobile, travel restricted populations of native or non-native wild animals. Overgrazing reduces the usefulness, productivity, and biodiversity of the land and is one cause of desertification and erosion. Overgrazing is also seen as a cause of the spread of invasive species of non-native plants and of weeds. Degrading land, emissions from animal agriculture and reducing the biomass in a ecosystem contribute directly to climate change. Overgrazing can be reversed or prevented by removing grazers in order to give plants time to recover between grazing events. Successful planned grazing strategies have been support in the American bison of the Great Plains, or migratory Wildebeests of the African savann ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shrub
A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees by their multiple stems and shorter height, less than tall. Small shrubs, less than 2 m (6.6 ft) tall are sometimes termed as subshrubs. Many botanical groups have species that are shrubs, and others that are trees and herbaceous plants instead. Some definitions state that a shrub is less than and a tree is over 6 m. Others use as the cut-off point for classification. Many species of tree may not reach this mature height because of hostile less than ideal growing conditions, and resemble a shrub-sized plant. However, such species have the potential to grow taller under the ideal growing conditions for that plant. In terms of longevity, most shrubs fit in a class between perennials and trees; some may only last about five y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
