What are the geographical field investigation sites in Huan County, Gansu Province?

Western hilly and gully region, northern hilly and gully region, southern hilly and gully region, and central river valley. According to the query of Gansu Dibao, the geographical field investigation sites of Huan County in Gansu Province are all hilly and gully areas in the west, hilly and gully areas in the north, hilly and gully areas in the southern remnant tableland, river valley around the river in the middle, Gansu, referred to as "Gan" or "Long" for short, provincial capitals Lanzhou, People's Republic of China (PRC) and provincial administrative regions. It is located in the northwest of China, bordering Shaanxi in the east, Xinjiang in the west and Sichuan and Qinghai in the south.