Survey report on the scope, terrain, climate, agriculture, and industry of Huangnan Prefecture.
Huangnan Tibetan Autonomous Prefecture is located in the southeast of Qinghai Province, at the first bend of the Jiuqu Yellow River, and in the southeast is connected with Xiahe County, Luqu County, Maqu County of Gannan Tibetan Autonomous Prefecture in Gansu Province and Maqin, Goluo Prefecture of this province. County is adjacent to the province, and the northwest is bordered by Tongde County, Guide County, Hainan Prefecture, and Hualong and Xunhua Counties in Haidong Region. Longwu Town, where the state capital is located, is 182 kilometers away from Xining City, the provincial capital. The total area of the state is 18,800 square kilometers, accounting for 2.63% of Ching Hai Province’s area.
The terrain of the autonomous prefecture is high in the south and low in the north. Zeku and Henan counties in the south belong to the Qingnan pastoral area, with an altitude of more than 3,500 meters and a cold climate. They are the main base for the development of animal husbandry in the autonomous prefecture; in the north are Jianzha and Tongren. County, the altitude is between 1900-4118 meters.
The climate in Huangnanzhou is a plateau continental climate. Its climate characteristics: rain and heat in the same season, with obvious differences between dry and wet seasons; insufficient heat, short frost-free period, large precipitation variability, and uneven spatial and temporal distribution; long sunlight hours and strong solar radiation; long, dry and cold cold seasons, and short, moist and cool warm seasons; Disaster weather. From 2001 to 2005, the temperature in Huangnan was relatively high, with little inter-annual variation. The temperature in the north gradually decreased slightly, with an annual average temperature of 6.6°C to 8.5°C. The temperature in the south was relatively high, with an annual average temperature of -0.9°C to 0.3°C. . The annual average temperature across the state is -0.9℃~8.5℃. The spatiotemporal distribution of precipitation is uneven, with large inter-annual variability, and it gradually shows an increasing trend. Compared with the historical precipitation values, the five-year average precipitation is slightly less in Jianzha and Henan areas, and slightly more in Tongren and Zeku areas. The five-year average precipitation is 308.4 mm in Jianzha County, 549.4 mm in Henan County, 409.1 mm in Tongren County, and 492.4 mm in Zeku County. The average annual precipitation across the state is 329.0 to 505.0 mm. The number of sunshine hours across the state ranges from 2506.1 to 2688.2 hours. The frost-free period ranges from 14 to 173 days, including 147 to 173 days in the northern warm zone and 14 to 21 days in the southern low temperature zone. The annual evaporation is 1231.6~1697.0 mm.