What is the first line of Qinling and Huaihe rivers?

The map of Qinling Huaihe River is as follows:

Geographical significance:

1, temperature: ① 10/October 1℃ isotherm (roughly passing through) ② warm temperate zone (north) subtropical zone (south) boundary.

2. Precipitation: ① Isoprecipitation Line with annual precipitation of 800mm (roughly passing through) ② Boundary between humid area (south) and semi-humid area (north) (1).

3. Climate: the dividing line between subtropical monsoon climate (south) and temperate monsoon climate and temperate continental climate (north).

4. Rivers: The rivers south of this line have large flow, small water level change, no ice age and small sediment concentration; Contrary to the north

5. Vegetation: the dividing line between temperate deciduous broad-leaved forest (north) and subtropical evergreen broad-leaved forest (south).

6. Planting: ① the dividing line between dryland agriculture (north) and paddy agriculture (south) (roughly) ② the dividing line between two crops (south) and three crops (north) a year.

Extended data

The Qinling Mountains in a broad sense is a huge east-west mountain range across the central part of China, starting from Baishi Mountain in the north of Lintan County in Gansu Province in the west and bounded by Dieshan Mountain and Kunlun Mountain.

Enter Shaanxi eastward through McKee in the south of Tianshui. At the junction of Shaanxi and Henan, it is divided into three branches, the northern branch is Xiaoshan, and the remaining veins extend eastward along the south bank of the Yellow River, commonly known as Mangshan; The middle branch is Xiong 'er Mountain; The south branch is Funiu Mountain.

A small part of the southern part of the mountain range extends from Shaanxi to Yunxian County, Hubei Province. The Qinling Mountains are 1600 km long and tens of kilometers to two or three hundred kilometers wide from north to south, covering a vast area.

Baidu Encyclopedia-Qinling-Huaihe Line