Daba Mountains

Geography

The Daba Mountains run in the general west-northwest to east-southeast direction, along the border between, on the one side (southwest and south) Sichuan and Chongqing, and on the other side (northeast and north) Shaanxi and Hubei. The mountains of Shennongjia are often considered the easternmost section of the Daba Range.

The southern slope of the Daba Mountains drains into the Sichuan Basin or directly into the Yangtze via short streams that flow into the river in the Three Gorges area, such as the Shen Nong Stream. The northern side drains into the Han River, a major tributary of the Yangtze, which, however, does not join the Yangtze until some hundreds kilometers to the east (in Wuhan).

The Daba Mountains' highest points are in the Shennongjia massif in Shennongjia Forest District. The three tallest peaks, located west of Muyu town, are Shennong Deng ("Shennong Peak", 3105 m elevation), Da Shennongjia ("Great Shennongjia", 3052 m), and Xiao Shennongjia ("Lesser Shennongjia", 3005 m, on the district's border with Badong County). Laojun Shan, 2936 m tall, is located northeast of Muyu.

In the southeast, the Daba Mountains are joined to the Wu Mountains, which block the Yangtze's flow out of the Sichuan Basin. In the east, the small Jingshan Range (in the southern part of the Xiangyang Prefecture) can be viewed as the extreme extension of the Daba Mountains. In the northeast, the Wudang Mountains are nearby; some authors even consider them a "branch" of the Daba Mountains.{{citation

In the rural counties of southern Hanzhong, in Shaanxi Province, there is a large area of karst with some of the largest sinkholes in the world, known as the Shaanxi tiankeng cluster or "Hanzhong tiankeng group". It covers nearly 5019 square kilometers and is located in four counties, Ningqiang County, Nanzheng County, Xixiang County, and Zhenba County, with the largest sinkhole (520 meters in diameter and 320 meters deep), near Sanyuanzhen (三元镇) in Zhenba County.

Natural environment

The natural landscape of the region, the Daba Mountains evergreen forests, is listed by the World Wildlife Fund (WWF) as one of the world's 200 ecoregions that should be a priority for conservation. Dabashan National Nature Reserve is located in the Chongqing part of the Daba Mountains (Chengkou County); Shennongjia Mountain Nature Reserve (704 km2), in Hubei (Shennongjia Forestry District).

The Dawn Redwood (Metasequoia glyptostroboides) is a deciduous conifer endemic to the Daba Shan, whose nearest living relatives are the Coast Redwood and Giant Sequoia of California. Redwoods formerly ranged across the northern hemisphere, but were thought to be extinct outside California until stands of Dawn Redwood were discovered in the Daba Shan in the 1940s.

Flora of the Daba Mountains File:VM 5248 Muyu hills forest mushroom.jpg|A forest mushroom (near Muyu, Shennongjia) File:VM 5356 G209 north of Muyu - bean tree.jpg|Decaisnea insignis (at about 2000 m elevation, north of Muyu) File:VM 5262 Muyu hills forest - blue flowers.jpg|Hosta ventricosa File:VM 5352 G209 north of Muyu - mountain conifer.jpg|Cryptomeria japonica File:VM 5156 G209 Wujiaping to Baishahe (Xingshan County).jpg|Chinese red pine (Pinus tabuliformis), in Xingshan County File:VM 5083 Xiqiuwan xiang Baishawan cun fields.jpg|Cunninghamia lanceolata (center), in Badong County

Land use

Presently, terraced agriculture is expanded in the Daba Mountains. A widely planted cash crop is the Eucommia tree, a medicinal plant.{{citation

Notes

References

References

1. (1878). "Encyclopædia Britannica, ''9th ed., Vol. V''".
2. "陕西发现天坑群地质遗迹并发现少见植物和飞猫". Sohu.com Inc..
3. (25 November 2016). "时事新闻--解密汉中天坑群——改写地质历史的世界级"自然博物馆"". Hanzhong People's Municipal Government.
4. {{WWF ecoregion