Changsha is located in the south of the Yangtze River in south-central China and north of the east of Hunan Province. It is located in the transition zone from the southern end of Dongting Lake Plain to the hilly basin in central Hunan, bordering Yueyang, Yiyang, Loudi, Zhuzhou, Xiangtan and Pingxiang in Jiangxi. Total area 1 18 18 square kilometers, of which the urban area is 954.6 square kilometers and the built-up area is 256 square kilometers (by the end of 2009). Qixingling of Dawei Mountain is located in Liuyang, with an altitude of 16 16 meters, which is the highest point in the jurisdiction. Yunlu Peak in Yuelu Mountain is 300.8 meters above sea level, which is the highest point in the urban area. Xiangjiang River is the most important river in Changsha, which runs through the whole territory from south to north and is about 75 kilometers long. Xiangjiang River runs through Changsha from south to north, dividing the city into Hedong and Hexi. Hedong is dominated by commercial economy, while Hexi is dominated by culture and education. 20011kloc-0/0 The residence of the municipal government was moved from Zheng Fan Street in Hedong to Guanshaling in Hexi, in order to develop Hexi economy and balance the two sides of Changsha. The map coordinates are east longitude11153'-145', north latitude 27 51'-28 40', which is about 230 kilometers from east to west and 88 kilometers from north to south. The area is in an east-west belt, with mountains on the north, west and south, hills in the southeast and hills in the northeast. Mountains, hills, hills and plains each account for a quarter. There are various soil types in Changsha, which can be divided into 9 soil types, 2 1 subclass, 85 soil genera, and 22 1 soil type, with a total area of 13662 mu, in which red soil and paddy soil account for 70% and 25% of the total soil area respectively. The rest are vegetable garden soil, fluvo-aquic soil, mountain yellow soil, yellow brown soil, mountain meadow soil, lime soil and purple soil, which are suitable for the growth of various crops. Changsha has a subtropical monsoon climate with four distinct seasons. It is rainy in late spring and early summer, and dry in late summer and early autumn; Spring is wet and changeable, summer and autumn are sunny, winter is short and summer is hot. The annual frost-free period is about 275 days, and the annual average temperature is 16.8 ~ 17.2℃, the extreme maximum temperature is 40.6℃, and the extreme minimum temperature is-12℃. The annual average total precipitation is 1422.4 mm, and the water resources are mainly surface water, with abundant water, and the annual average surface runoff is 80.8 billion cubic meters. Except Xiangjiang River, there are 15 tributaries flowing into Xiangjiang River, mainly Liuyang River, Laodao River, Jinjiang River and Weishui River. The largest reservoirs are Huangcai Reservoir in Ningxiang County and Zhushuqiao Reservoir in Liuyang City.