Karst

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File:Karst.jpg
South China Karst Terrain

China is one of the countries in the world with largest carbonate rock occurred, and it is in south China that the most typical and diverse karst landforms developed. Centered by Guizhou Province and covering some 600,000 square kilometers the South China Karst terrain is believed the largest single karst area in the world, including eastern Yunnan, most of Guizhou, with a major extension into parts of Chongqing, Sichuan, Hunan, Hubei and Guangdong. With high altitude plateau (average 2000-2200 meters elevation) in the northwest and low-lying plain (average 100-120 meters elevation) in the southeast, the overall topography features a giant slope declining from northwest to southeast.


South China Karst is the title of the serial application for the World Natural Heritage by Chinese Government. The nominated property (Phase 1) comprises three areas of Chongqing Wulong Karst (gorge), Guizhou Libo Karst (cone) and Yunnan Shilin Karst (pinnacle). The total area of the three sites covers core area of 476 sq.km. and the buffer zones of 984 sq.km.

Form different perspectives, the karst areas comprehensively reflect the unique natural features of the South China Karst terrain, highlighting its special and representative karst landforms, karst ecosystem and biodiversity, and exceptional natural beauty.

Geologically, the South China Karst region is located in the southwest margin of Yangtze landmass, in most Paleozoic and early Mesozoic period (Cambrian to Triassic), this region was oceanic environment with lower latitude than present. Thousands meters thick carbonate layers, particularly late Paleozoic period (Devonian, Carboniferous and Permian), deposited. Due to earth movement, this region was uplifted as land since late Triassic and started its karst landform development. Drawn by the Himalayan mountain building since late Tertiary, this region experienced a rapid tilting uplift which resulted in its today's sloping topography.

Long tern complex geological evolution gave rise to exceptional diverse karst landforms in this region, including the most typical karst landforms in the world of tower kart (Fenglin), pinnacle karst (Stone Forest), and cone karst (Fengcong), as well as some unusual karst phenomena such as Tiankeng (giant karst pit) and Difeng (deep karst fissure). Besides, there are numerous spectacular underground cave systems and rich cave sediments. All these make this region the world's "museum of continental tropic-subtopic karst" because of its unrivaled richness and uniqueness.

Within the South China Karst area, the thick carbonate layers that deposited from Cambrian to Triassjc contain some globally significant fossils such as the Fauna of keichousaurus Hui , etc. which are the important life record of the earth.

The nominated area has richest biodiversity, containing abundant rare, endangered and indigenous pant and animal species. In Chogngqing and Guizhou karst areas there are more than 6000 higher plant species, including D.involucrate, C. argyrophyll, Cycas guizhouensis, Taxus chinensis, etc. threatened and endemic species. This karst terrain is not only the home to plenty of animals ranging from beasts, birds, amphibians, fish as well as cave animals but also the home to many threatened and indigenous, species such as Presbytis francoisi, Neofelis nebulosa, Aqila chrysaetos, Moschus berezovskit, etc. i.e, the nominated area is the sanctuary to many threatened plant and animal species.

Rich and unique karst landforms contained in the nominated area display exceptional natural beauty, many areas have long been traditional Chinese scenic resorts for hundreds years, of which, the tiankengs in Chongqing, Stone Forest in Yunnan and the Guizhou waterfalls are world-renown natural wanders.


Wulong Karst

The Wulong Karst is located at Wujiang River downriver of Southeastern Chongqing, and it includes three karst systems of Sanqiao Natural Bridges, Furong Jiang karst gorge and caves round, and Houping erosion tiankengs, which are distributed in mid-north, southeast and northeast of Wulong County respectively. It consists of gorges, natural bridges, tiankengs, caves, shafts subterranean streams and resurgences, developing in the carbonate rocks of Cambrian-Ordovician systems and Permian-Triassic systems.

The macro-landform in this terrain is featured by two-leveling mountain planes with elevations of 1800-2000m and 1200-1500m and deep-cut gorges. The three karst systems lie in the bank, interfluve and headstream of Wujiang River branches respectively; and they formed an interrelated integrity for its developing successively and distributing in sequence.

Wujiang River is one of big tributaries of Yangtze River, with a section of 79km long in Wulong and an incised depth of one kilometer. It influenced intensely the development of its branches such as Furong Jiang, Yangshui He, Muzong He geomorphic systems, for its continuous river incising and vadose zone increasing since the tertiary, and it is the main dynamic genesis of Wulong Karst.

The Wulong Karst records vividly the unique characters of gorge, cave and tiankeng karst development and evolvement under the intermittence tectonic uplifting conditions in Three Gorges area since Cenozoic era for 65Ma, representing major stages of earth evolutionary history.

Big Events of Wulong Karst:

  • May 1993-Furong Dong was discovered;
  • May 1994-Furong Dong show cave was opened;
  • Since 1994-Approximately 100km long cave passages have been surveyed by cavers from over ten countries;
  • March 2001-Qingkou tiankeng as erosion tiankeng type was discovered by Prof. Zhu Xuewen;
  • October 2003-Wulong Karst was ratified National Geopark of China by Ministry of Land and Recourses;
  • January 2006-Wulong Karst, as a part of South China Karst, applied for world natural heritage.