Korea once had large timber resources. In the North, reforestation and conservation programs have helped reverse the effects of excessive cutting during the Japanese occupation (1910–45). Predominant trees are larch, oak, alder, pine, spruce, and fir. Forests in the South were depleted as a result of illegal cutting after 1945 and damage during the Korean War (1950–53), but reforestation programs have helped to remedy the loss.
Korea has great mineral wealth, most of it (80%–90%) concentrated in the North. Of the peninsula's five major minerals—gold, iron ore, coal, tungsten, and graphite—only tungsten and amorphous graphite are found principally in the South. South Korea has only 10% of the peninsula's rich coal and iron deposits. Its minerals are widely scattered, and mining operations are generally small scale, although tungsten is an important export item. North Korea is especially rich in iron and coal and has some 200 different minerals of economic value. Some of the other more important minerals that are produced are lead, zinc, copper, uranium, manganese, gold, silver, and tungsten.
Because of the mountainous and rocky terrain, less than 20% of Korean land is arable. Rice is the chief crop, with wet paddy fields constituting about half of the farmland. Paddies are found along the coasts, in reclaimed tidal areas, and in river valleys. Barley, wheat, corn, soybeans, and grain sorghums are also extensively cultivated, especially in the uplands; other crops include potatoes, pulses, cotton, tobacco, vegetables, fruits, and sweet potatoes. Cattle, pigs, and chickens are raised. Before the country was divided (1945), the colder and less fertile north depended heavily upon the south for food. Agricultural self-sufficiency became a major goal of the North Korean government, and mechanized methods were introduced there in and in the South. Both governments expanded irrigation facilities, constructed numerous dams, and initiated land reclamation projects; however, the North has suffered severe food shortages. Livestock previously played a minor role in Korean agriculture, especially in the North, where the steep and often barren hills are unsuitable for large-scale grazing, but since the end of the Korean War beef has become a significant component of the diet in the South.
The fishing waters off Korea are among the best in the world; the long coastline and numerous islands, inlets, and reefs provide excellent fishing grounds, and the presence of both a warm and a cold current attracts a great variety of species. Korean deep-sea fishing ships range into the Atlantic and Arctic oceans, and species are also raised in aquaculture facilities.
The Korean economy was shattered by the war of 1950 to 1953. Postwar reconstruction was abetted by enormous amounts of foreign aid (in the North from Communist countries and in the South chiefly from the United States) and intensive government economic development programs. The greatest industrial advances were made during the 1960s; in that decade the South experienced an 85% increase in productivity and a 250% rise in per capita gross national product. Economic development throughout Korea has been uneven, with the South showing significantly greater gains. The per capita gross domestic product of the South is more than 15 times that of the North. In the South such consumer goods industries as textiles, garments, and footwear have given way to heavy industry, consumer electronics, and information industries. A great variety of products are now manufactured; these include electrical and electronic equipment, automobiles, chemicals, ships, steel, and ceramic goods. South Korea exports semiconductors, wireless telecommunications equipment, motor vehicles, computers, steel, ships, and petrochemicals. Imports include machinery, electronics, oil, steel, transportation equipment, organic chemicals, and plastic. The main trading partners are China, Japan, and the United States.
The North, too, has changed from a predominantly agricultural society (in 1946) to an industrial one. With abundant mineral resources and hydropower, 70% of its national product is now derived from mining, manufacturing, and services; about 30% still comes from agriculture. Development was impeded, however, by the rigid economic system, and the economy severely affected by a loss of trading partners after the collapse of East European Communism. The amount of resources devoted to the military, one of the world's largest, has been a burden on the economy as well. In 2002 the government instituted a series of limited economic reforms, including letting markets set prices of many goods and services and permitting private traders. Major North Korean industries include mining (coal, iron ore, limestone, magnesite, graphite, copper, zinc, lead, and precious metals), food processing, and the manufacture of military products, machines, electric power, chemicals, and textiles (synthetics, wool, cotton, silk). Exports include minerals, metallurgical products, armaments, and textiles. Petroleum, coal, machinery and equipment, textiles, and grain are the main imports. The chief trading partners are China, South Korea, and Thailand.
The industrialization of both North and South has been accompanied by improved transportation. By the end of the Korean War the rail system had been destroyed, and paved highways were almost nonexistent. The railroads have been extensively rebuilt, and in the South high-speed lines connect Seoul with Daegu and Busan in the southeast and Gwangju in the southwest. The South Korean government also has completed a series of superhighways connecting Seoul with numerous major cities. There is domestic air service, and international airports are located at Seoul, Busan, and Pyongyang. The expansion of port facilities at Busan and Incheon has vastly increased their capacity.