Manchuria's vast timber reserves have been damaged by excessive cutting. Mineral resources, chiefly coal and iron, are concentrated in the southwest; there is a large colliery at Fushun and a large steel mill at Anshan. Magnesite, copper, lead, and zinc are also important, and there is a large oil field at Daqing, NW of Harbin. Uranium and gold deposits have also been found.
The great Manchurian plain (average elevation c.1,000 ft/300 m), crossed by the Liao and Songhua rivers, is the only extensively level area. Fertile and densely populated, it has been a major manufacturing and agricultural center of China. One of the few areas in the country suitable for large-scale mechanized agriculture, it has numerous collective farms. Long, severe winters limit harvests to one a year, but considerable quantities of soybeans are produced. Sweet potatoes, beans, and cereals (including rice, wheat, millet, and kaoliang) are also grown, and cotton, flax, and sugar beets are raised as industrial crops. The processing of soybeans into oil, animal feed, and fertilizer is centered in cities in or near the plain, notably Changchun, Harbin, and Shenyang. Livestock are raised in the north and the west, and fishing is important off the Yellow Sea coast.
The chief commercial port is Dalian; Lüshun, which is administratively part of Dalian, is a major naval base. All rivers are navigable, but only the Songhua has significant heavy traffic. When the rivers freeze, they are used as roadways. An extensive rail system connects the hinterland with the coastal ports; major lines are the South Liaoning RR and the Northeast RR. The building of the railroads (after 1896) spurred industrial development. Manchuria is a great industrial hub, with huge coal mines, iron- and steelworks, aluminum-reduction plants, paper mills, and factories making heavy machinery, tractors, locomotives, aircraft, and chemicals. Since the 1980s, however, the region's inefficient state-controlled companies have had trouble gearing production to an economy that is increasingly market-oriented.