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Author： Source： Updated：2019-06-24
Modern karst in China is developed on the basis of the peneplain after Yanshan movement. In the old Tertiary period, South China had tropical climate and the peak forest began to develop; North China had subtropical climate, and some watersheds in mountains of middle Shanxi and the southern section of Taihang Mountain still have hill-depression landforms. However, the north and south on the Yangtze River at that time were desert areas, which were areas with weak karst development. During the New Tertiary period, the formation of monsoon climate in China laid the foundation for today's karst zone. South China maintained hot and humid, Central China became humid, and karst development became fierce. Especially since the Quaternary period, the crust has risen fast together with rapid, complex, and diverse development of karst landform. Climatic zone changed frequently with a gradual southward shift during the alternating glacial period and interglacial period. The northern boundary of tropical peak forest in southern China reached Nanling Mountains and Miaoling Mountains, in latitude 25°40’ north at Dao County, Hunan and about latitude 26° north in Guizhou. This boundary is about 3 to 4 latitudes north compared with the current tropical boundary, so we can see that the northern boundary of peak forest is not formed under modern climatic conditions. Although the temperature and rainfall in eastern China change gradually northwards, the difference in karst zones is very obvious. This is because of the impact of the glacial and interglacial climates: the temperature and rainfall during the interglacial period were high in China, which was conducive to karst development; while it was cold with little rainfall in glacial period, which strongly inhibited karst development. However, the more tropical it goes, the smaller the impact will be. In tropical peak forest area, the conditions for intermittent development of peak forest were maintained while the influence from Central China to the northeast was increasing; the intensity of karst effect rapidly decreased to the north, causing significant changes in type. The vast northwestern region has been in a dry climate since Tertiary period and is a region where karst almost does not develop.