evidence: The Yalu River, also known as the Amnok River, is an 800-kilometer long river in northeastern Asia forming the natural boundary between northwestern Korea and northeastern China. The river arises from the Tian Lake on top of Mount Paektu in the Changbai Mountains (which form the border between the Chinese provinces of Jilin and Liaoning and North Korea), and drains into the Korea Bay between Dandong in China and Sinuiju in North Korea, occupying a basin of 31,750 square kilometers. The Tokro, Ai, Hochon, and Changjin are the major tributaries of the Yalu River. 200 islands belonging to either China or North Korea exist on the river. [...] The Yalu River not only acts as the political boundary between North Korea and China, but also serves as a cultural boundary between these two countries. The river is also an important source of hydroelectric power generation, and several dams and hydroelectric power stations, like the Sup'ung Dam, the Taipingwan Dam, and the Yunfeng Dam, have been built upon the river. The Sup'ung Dam is one of the largest hydroelectric power stations in Asia, with a capacity of generating around 7 million kilowatts of electricity. Only about 89,000 hectares of land are arable along the river basin, and most of this is used for growing rice, corn, millet, and sweet potatoes. Fishing in the Yalu River also sustains the livelihoods and helps meet the protein needs of the Chinese and Korean populations settled along the river.