Geographical environment of Tonghe county

Tonghe County is located in the middle of Heilongjiang Province, at the southern foot of Xiaoxing 'anling and the north bank of the middle reaches of Songhua River, with the geographical coordinates of1287' 30 "-12924' 30" and the north latitude of 45 52' 30 "-46 37' 30". It borders yilan county in the east, Mulan County in the west, Fangzheng County and Binxian County across the Songhua River in the south, and tieli city County and Qing 'an County in the north with Pingdingshan watershed as the boundary. Tonghe is about 89.7 kilometers long from east to west, 87 kilometers wide from north to south and covers an area of 5,678 kilometers. Tonghe Town, where the CPC Tonghe County Committee and Tonghe County People's Government are located, is located in the south of the county, on the north bank of Songhua River, and 0/70km east of Harbin/KLOC. It is the political, economic, cultural and transportation center of Tonghe County, and the largest water transport port between Harbin and Jiamusi City.

The northern mountainous area belongs to Xiaoxing 'anling. The highest peak elevation is 1 100 meters, with an average elevation of 400-800 meters. The maximum slope is 70, and the gullies and canyons are mostly V-shaped. Soil-forming parent materials belong to bedrock and alluvium. Its crust can reach 70 kilometers thick and is divided into upper and lower layers. The upper layer is granite, which is also called silicon-aluminum layer because it is rich in silicon and aluminum. The lower layer is basalt, which is rich in silicon and magnesium, also called silicon-magnesium layer. The surface layer of the earth's crust is influenced by the atmosphere, water and organisms, forming soil layer, weathering crust and sedimentary layer, with a thickness of 0- 10 km, accounting for 70% of the total area. There are two forestry bureaus, Qinghe and Tonghe, and the county forestry bureau forest farm located in the mountainous area.

The hilly and shallow mountainous area in the middle has gentle mountains and wide valleys. Generally, the average altitude is between 200-500m, the slope of the top of the mountain is above 40, and the slope is about 15-20. Physical weathering is strong, and soil-forming parent material belongs to residual slope accumulation. These hills belong to Zhongshan District. The south is closely connected with the piedmont and distributed in the periphery of the mountain area, which is a hilly area with an altitude of about 200 meters. The vast plains have been reclaimed as cultivated land, and hilly areas are suitable for afforestation and fruit tree production. The mountain extends south, close to the north bank of Songhua River, belonging to the piedmont plateau area. Spring is dry and windy. From early March to late May, the temperature remained stable at -6℃ for about 76 days, and the average rainfall was 16% of the whole year.

Summer is short and rainy. From late May to early September, the temperature was stable above 12.8℃ for about 109 days. High temperature concentrated rainfall accounts for 63% of the annual rainfall.

In autumn, the temperature is generally stable at 13.3℃ for about 50 days. The average temperature is 4.6 degrees Celsius.

From the first ten days of 10 in winter to the first ten days of March the following year, the average daily temperature is-17.5℃, and the duration is about 130 days. There are 430,000 mu of water surface and 27 rivers. The density of river network is 0.4 Wei/km2. Except Songhua River, there are 16 large rivers. Namely: Chalin River, Northwest River, Xiaogudong River, Dagudong River, Mihe River, Fulahun River, Wulahun River, Datong River, Shahezi River, Zhuanxinhu River, Xiaoqiao River, Toudao River, Xiaotong River, Linzi River, Xi Erdao River and Sidao River are all first-class tributaries of Songhua River. There are 275 large and small bubbles in Tonghe County, and the larger bubbles are Leaping Bubble and Hahaha Bubble, with the maximum water surface of 42.95 square kilometers, storage capacity of 762 1.000 cubic meters, normal water surface of 30.29 square kilometers and storage capacity of 46 1. 1.000 cubic meters.