|
Qinling Huaihe Line
The Qinling () or Qin Mountains, formerly known as the Nanshan ("Southern Mountains"), are a major east–west mountain range in southern Shaanxi Province, China. The mountains mark the divide between the drainage basins of the Yangtze and Yellow River systems, providing a natural boundary between North and South China and support a huge variety of plant and wildlife, some of which is found nowhere else on earth. To the north is the densely populated Wei River valley, an ancient center of Chinese civilization. To the south is the Han River valley. To the west is the line of mountains along the northern edge of the Tibetan Plateau. To the east are the lower Funiu and Dabie Shan which rise out of the coastal plain. The northern side of the range is prone to hot weather, however the physical barrier of the mountains mean that the land to the North has a semi-arid climate, with the lack of rich, fertile landscape that can not support a wealth of wildlife. The mountains also acted ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Qin (state)
Qin () was an ancient Chinese state during the Zhou dynasty. Traditionally dated to 897 BC, it took its origin in a reconquest of western lands previously lost to the Rong; its position at the western edge of Chinese civilization permitted expansion and development that was unavailable to its rivals in the North China Plain. Following extensive "Legalist" reform in the fourth century BC, Qin emerged as one of the dominant powers of the Seven Warring States and unified the seven states of China in 221 BC under Qin Shi Huang. It established the Qin dynasty, which was short-lived but greatly influenced later Chinese history. History Founding According to the 2nd century BC historical text ''Records of the Grand Historian'' by Sima Qian, the Qin state traced its origin to Zhuanxu, one of the legendary Five Emperors in ancient times. One of his descendants, Boyi, was granted the family name of Yíng by Emperor Shun. During the Xia and Shang dynasties, the Yíng clan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spiral (railway)
A spiral (sometimes called a spiral loop or just loop) is a technique employed by railways to ascend steep hills. A railway spiral rises on a steady curve until it has completed a loop, passing over itself as it gains height, allowing the railway to gain vertical elevation in a relatively short horizontal distance. It is an alternative to a zig-zag, and avoids the need for the trains to stop and reverse direction while ascending. If the train is longer than the length of each loop it may be possible to view it looping above itself. The term "loop" is also often used for a railway that curves sharply and goes back on itself: if the railway crosses itself, then it forms a spiral or helix; otherwise, it forms the much more common horseshoe curve or bend. List of spirals Argentina * Two spirals between Tacuara and Meseta at and on the heritage '' Tren a las Nubes'' section of the Salta–Antofagasta railway part of the General Manuel Belgrano Railway. Australia * Spiral on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quercus Acutissima
''Quercus acutissima'', the sawtooth oak, is an Asian species of oak native to China, Tibet, Korea, Japan, Indochina (Vietnam, Thailand, Myanmar, Cambodia) and the Himalayas (Nepal, Bhutan, northeastern India). It is widely planted in many lands and has become naturalized in parts of North America. ''Quercus acutissima'' is closely related to the Turkey oak, classified with it in ''Quercus'' sect. ''Cerris'', a section of the genus characterised by shoot buds surrounded by soft bristles, bristle-tipped leaf lobes, and acorns that mature in about 18 months. Description ''Quercus acutissima'' is a medium-sized deciduous tree growing to tall with a trunk up to in diameter. The bark is dark gray and deeply furrowed. The leaves are long and wide, with 14–20 small saw-tooth-like triangular lobes on each side, with the teeth of very regular shape. The flowers are wind-pollinated catkins. The fruit is an acorn, maturing about 18 months after pollination, long and 2 cm br ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northern And Southern China
Northern China () and Southern China () are two approximate regions within China. The exact boundary between these two regions is not precisely defined and only serve to depict where there appears to be regional differences between the climates and localities of northern regions of China vs southern regions of China. Nevertheless, regional differences in culture and language have historically fostered a number of local identities. Extent Often used as the geographical dividing line between northern and southern China is the Qinling–Huaihe Line (lit. Qin Mountains– Huai River Line). This line approximates the 0 °C January isotherm and the isohyet in China. Culturally, however, the division is more ambiguous. In the eastern provinces like Jiangsu and Anhui, the Yangtze River may instead be perceived as the north–south boundary instead of the Huai River, but this is a recent development. There is an ambiguous area, the region around Nanyang, Henan, that lies in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yangtze River
The Yangtze or Yangzi ( or ; ) is the longest list of rivers of Asia, river in Asia, the list of rivers by length, third-longest in the world, and the longest in the world to flow entirely within one country. It rises at Jari Hill in the Tanggula Mountains (Tibetan Plateau) and flows in a generally easterly direction to the East China Sea. It is the List of rivers by discharge, seventh-largest river by discharge volume in the world. Its drainage basin comprises one-fifth of the land area of China, and is home to nearly one-third of the demographics of China, country's population. The Yangtze has played a major role in the history of China, history, culture of China, culture, and economy of China. For thousands of years, the river has been used for water, irrigation, sanitation, transportation, industry, boundary-marking, and war. The prosperous Yangtze Delta generates as much as 20% of historical GDP of China, China's GDP. The Three Gorges Dam on the Yangtze is the list ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drainage Divide
A drainage divide, water divide, ridgeline, watershed, water parting or height of land is elevated terrain that separates neighboring drainage basins. On rugged land, the divide lies along topographical ridges, and may be in the form of a single range of hills or mountains, known as a dividing range. On flat terrain, especially where the ground is marshy, the divide may be difficult to discern. A triple divide is a point, often a summit, where three drainage basins meet. A ''valley floor divide'' is a low drainage divide that runs across a valley, sometimes created by deposition or stream capture. Major divides separating rivers that drain to different seas or oceans are continental divides. The term ''height of land'' is used in Canada and the United States to refer to a drainage divide. It is frequently used in border descriptions, which are set according to the "doctrine of natural boundaries". In glaciated areas it often refers to a low point on a divide where it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BioScience
''BioScience'' is a monthly peer-reviewed scientific journal that is published by Oxford University Press on behalf of the American Institute of Biological Sciences. It was established in 1964 and was preceded by the ''AIBS Bulletin'' (1951–1963). The journal publishes literature reviews of current research in biology, as well as essays and discussion sections on education, public policy, history of biology, and theoretical issues. Abstracting and indexing The journal is abstracted and indexed in MEDLINE/PubMed (1973–1979), the Science Citation Index, Current Contents/Agriculture, Biology & Environmental Sciences, The Zoological Record, and BIOSIS Previews. According to the ''Journal Citation Reports'', the journal has a 2020 impact factor of 8.589. References External links * {{Official website, http://bioscience.oxfordjournals.org/ Journal pageat the American Institute of Biological Sciences The American Institute of Biological Sciences (AIBS) is a nonprofit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecoregion
An ecoregion (ecological region) or ecozone (ecological zone) is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than a biogeographic realm. Ecoregions cover relatively large areas of land or water, and contain characteristic, geographically distinct assemblages of natural communities and species. The biodiversity of flora, fauna and ecosystems that characterise an ecoregion tends to be distinct from that of other ecoregions. In theory, biodiversity or conservation ecoregions are relatively large areas of land or water where the probability of encountering different species and communities at any given point remains relatively constant, within an acceptable range of variation (largely undefined at this point). Three caveats are appropriate for all bio-geographic mapping approaches. Firstly, no single bio-geographic framework is optimal for all taxa. Ecoregions reflect the best compromise for as many taxa as possible. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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' Food and Agriculture Organization (FAO) defines a forest as, "Land spanning more than 0.5 hectares with trees higher than 5 meters and a canopy cover of more than 10 percent, or trees able to reach these thresholds ''in situ''. It does not include land that is predominantly under agricultural or urban use." Using this definition, '' Global Forest Resources Assessment 2020'' (FRA 2020) found that forests covered , or approximately 31 percent of the world's land area in 2020. Forests are the predominant terrestrial ecosystem of Earth, and are found around the globe. More than half of the world's forests are found in only five countries (Brazil, Canada, China, Russia, and the United States). The largest share of forests (45 percent) are in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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, after flowering; and to the shedding of ripe fruit. The antonym of ''deciduous'' in the botanical sense is evergreen. Generally, the term "deciduous" means "the dropping of a part that is no longer needed or useful" and the "falling away after its purpose is finished". In plants, it is the result of natural processes. "Deciduous" has a similar meaning when referring to animal parts, such as deciduous antlers in deer, deciduous teeth (baby teeth) in some mammals (including humans); or decidua, the uterine lining that sheds off after birth. Botany In botany and horticulture, deciduous plants, including trees, shrubs and herbaceous perennials, are those that lose all of their leaves for part of the year. This process is called ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Maiji
The Maijishan Grottoes (), formerly romanized as Maichishan, are a series of 194 caves cut in the side of the hill of Maijishan in Tianshui, Gansu Province, northwest China. This example of rock cut architecture contains over 7,200 Buddhist sculptures and over 1,000 square meters of murals. Construction began in the Later Qin era (384–417 CE). They were first properly explored in 1952–53 by a team of Chinese archeologists from Beijing, who devised the numbering system still in use today. Caves #1–50 are on the western cliff face; caves #51–191 on the eastern cliff face. They were later photographed by Michael Sullivan and Dominique Darbois, who subsequently published the primary English-language work on the caves noted in the footnotes below. The name Maijishan consists of three Chinese words () that literally translate as "Wheatstack Mountain", but because the term "mai" () is the generic term in Chinese used for most grains, one also sees such translations as "Corn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
