Where is Amur-Heilong Basin? – This question sounds trivial, however it has rather tricky answer.
The largest portion of the Amur-Heilong River basin, about 1 million km2, lies within the Russian Federation. The river basin includes six Russian provinces: Primorsky Province, Khabarovsky Province, Amur Province, Chitinskaya Province, Aginsky-Byryatsky Autonomous Region, and Evreiskaya Autonomous Province. The latter two are the only Russian provinces that lie completely within the Amur-Heilong River basin. Vladivostok, the capital of Primorsky Province is the only provincial capital located outside the basin (see Map)
The Amur-Heilong basin area in China covers more than 0.9 million km2 in parts of three provinces: Heilongjiang, Jilin, and Inner Mongolia. It also occupies some 300 km2 in Liaoning Province. The total area of the basin within Heilongjiang Province is 447,400 km2, or over 98% of province land area. The basin in Jilin Province includes 5 cities and 30 counties, and covers an area of 134,700 km2, or nearly 72% of the province land area. In Inner Mongolia all cities of Hulunbuir (253,000 km2) and Xing'an Meng (59,806 km2) prefectures lie within the basin, which covers an area of 323,600 km2 and drains over 27% of Inner Mongolia's total land area.
The eastern part of Mongolia lies in the Amur-Heilong River basin. Here Mongolia borders the Russian Federation to the north and the People's Republic of China to the east and south-east. The total basin area in Mongolia is approximately 230,000 km2 or 14 per cent of the national territory. However, only the Onon River with a watershed of 30,000 km2 drains into the Amur-Heilong system annually, while the more southerly Kherlen and Khalkh Rivers only drain into the Amur-Heilong Basin in wet years via Dalai Lake. Mongolian Provinces in the Amur-Basin include Hentiy and Dornod aimags (provinces) and 3 soums (counties) of Tuv province (Mongonmorit, Bayandelger and Bayanjargalan) and 4 counties of Sukhbaatar aimag (Monkhkhaan, Tumentsogt, Sukhbaatar and Erdenetsagaan).
Tianchi Lake (Heaven's Pool) of Changbai Mountains is the source of Songhua River and is divided between China and Democratic People's Republic of Korea. Therefore Amur Basin includes at least 100 km2 of North Korean territory.
Population density, ethnic composition and cultural traditions differ very significantly between countries of the basin. Nevertheless constant migration of population between three basin countries has been going on for many centuries.
Amur River Mouth empties into the Sea of Japan and Sea of Okhotsk via Tatar Straights and to a large extent determines chemical composition and biological productivity of these waters so important for Japanese and other Northeast Asian fishermen. Therefore, although none of the basin area lies within the bounds of Japan or South Korea, both nations' economies heavily depend on its environmental condition. For them it has much greater economic importance than any of the many rivers crossing their own territory.
Major migratory bird flyways criss-cross the basin and connect it to remote countries of South and Southeast Asia, and even Australia. European countries also receive birds breeding in Amur Basin. Therefore, through vital ecological links Amur-Heilong is firmly connected with the half of the world in one life-supporting system. Therefore its ecological well-being is of global concern and world-wide importance.