Characteristics and reasons of urban distribution along the Yangtze River?

Characteristics and reasons of urban distribution along the Yangtze River?

They are all cities near the sea and by the river

Distribution characteristics of cities along the Yangtze River

Distribution characteristics of cities along the Yangtze River
The area of Poyang Lake Plain is about 10000 square kilometers. Most of them are below 50 meters above sea level. The terrain is high in the north and low in the south. The water network is dense and the soil is fertile. In addition to the red soil hills on the edge, the flood plain in the middle of Poyang Lake Plain is mainly formed by the scouring and silting of rivers such as Gan, Fu, Xin, Po and Xiu. Among them, Ganjiang River is the main river. The area is about 20000 square kilometers, The surface is covered with red soil and river alluvium. The Yangtze River Plain in Jiangsu and Anhui Province mainly refers to the long and narrow alluvial plain distributed along both sides of the Yangtze River from hukou to Zhenjiang, including Wuhu plain and Chaohu plain. The plain is wide and narrow, and the river flows from time to time, and the flow velocity is gentle; from Datong to below, the flow velocity is slower, and the sediment deposition is strengthened, especially when the river passes through the rocky mound, There are many lakes on both sides of the river. From the estuary below Zhenjiang River, the Yangtze River delta develops. To the north of the delta is Lixiahe plain. The plain is a dish shaped depression with high, medium and low Zhou. The north edge of the depression is the old yellow river channel; the South edge is the North Bank of the Yangtze River Delta; the west edge is Hongze Lake and Yunxi dike; and the east edge is the coastal plain of Northern Jiangsu

The topography along the Yangtze River is the main central city?
There is only one central city. This is the question we got in the geography examination of grade two in Urumqi. Please help me

Yangtze River Central City: upstream: Chongqing (located in Sichuan Basin) midstream: Wuhan (located in Jianghan plain) downstream: Nanjing (located in southern Jiangsu Plain) Estuary: Shanghai (located in Taihu Plain)

Why are tropical cities mainly distributed on the plateau? Considering the climate, topography and other natural factors

Because the tropical climate is hot and humid, the temperature is high, while the plateau temperature is relatively low, because the temperature decreases with altitude
There is a plateau, the plateau is generally flat and open, so conducive to urban construction