an island in the Pacific Ocean and the second largest island in the world after Greenland. It lies 150 km north of Australia, from which it is separated by the Torres Strait. On the south it is bounded by the Arafura and Coral seas. Area, 829,000 sq km. Population, about 3.2 million (1971). The western part of the island, called Irian Jaya, is a province of Indonesia; since 1975 the southeastern part has been the state of Papua New Guinea.
Natural features. The coasts are highly indented, particularly in the west and east, forming the large bays of Sarera, Berau, and Huon. On the flat and sandy southern coast is the large Gulf of Papua. The high northern coast is steep in places and has no large protected bays.
TERRAIN. Most of New Guinea is mountainous. A high mountain chain consisting of a series of separate ranges rising to 3,000–4,000 m stretches from west to east across the central part of the country. The highest peak is Mount Djaja (5,029 m) in the Sudirman Mountains. Alpine relief forms are characteristic of the high mountains. At elevations above 4,000 m there are perennial snows and small glaciers covering 14.5 sq km. Along the northern coast stretch the middle-elevation Coastal Mountains (1,000–2,000 m), which descend abruptly to the sea on the Miklukho-Maklai Coast. There are many active volcanoes in the north. The southern part of the island is a vast low-lying plain, hilly in places, intersected by numerous rivers, and very swampy in the southwest. Landslides play an important role in the formation of terrain.
GEOLOGICAL STRUCTURE AND MINERAL RESOURCES. Australian Precambrian and Paleozoic platform structures are found in the south. The folded foundation is composed of Proterozoic metamorphic formations in the southwest and Upper Paleozoic strata breached by granitoids in the southeast. The platform mantle consists of Paleozoic, Mesozoic, and Cenozoic marine deposits. The main ophiolite belt of the Upper Cretaceous and Paleogene is in the Owen Stanley Range. North of the belt lies a Cenozoic geosynclinal zone, composed of Paleogene basalt, andesite, tuffs, and marine sediments. A pre-Miocene zone of ophiolites and a belt of recent geosynclinal strata extend along the northern coast. In the south, the Upper Cretaceous deposits contain oil and gas; the main ophiolite zone, chrome and nickel; and the Owen Stanley Range, copper-sulfide ore.
CLIMATE. The northern half of New Guinea has an equatorial climate, and the southern half a subequatorial climate. Average monthly temperatures on the plains range from 25° to 28°C. In the mountains, with increasing elevation, the climate changes from mountain tropical to nival. There is rainfall throughout the year, with the greatest amount occurring during the northwest summer monsoon (more than 4,000 mm annually; in the mountains more than 6,500 mm). Typhoons are frequent. The southeastern and to some extent the southern parts of the island are affected by the Australian winter monsoon and receive less rainfall. Port Moresby, with an annual precipitation of 1,000 mm, is the “driest” place in New Guinea.
RIVERS. The island’s rivers are notable for their length; the Fly, Mamberamo, Digul, Sepik, and Ramu are more than 500 km long. The rivers rise in the mountains, and as they enter the coastal plains, their valleys widen and currents become slower. They are navigable in their lower course.
SOILS AND FLORA. Red-yellow lateritic soils are found in the lowlands. At elevations of about 1,000 m they are replaced by mountain lateritic, more podzolized soils. Yellow, red, and yellow-brown soils appear at elevations of 2,000–3,000 m. The highest summits have mountain-meadow soils. Destruction of forest vegetation, plowing (frequently along the slopes), strong winds, and typhoon rains have eroded the soil.
The flora of New Guinea is highly diversified. The plains and mountain slopes up to 500–1,000 m are covered with tropical evergreen rain forests with admixtures of palms, bamboos, arborescent ferns, and pandanuses. At elevations of 1,000 m to 2,000 m there-are mountain tropical rain forests containing various species of Araucaria and evergreen beech. High-mountain meadows and growths of pulvinate shrubs are found on the summits. In the south there are tropical swamp forests and sparse forests of eucalyptus and acacia interspersed with savannas. Of New Guinea’s more than 6,800 species of plants, 85 percent are endemic.
FAUNA. New Guinea falls within the Papuan subregion of the Australian zoogeographic region. Among the ancient animals that have survived on the island are the oviparous echidnas and various marsupials—tree kangaroos, cuscuses, bandicoots, and dasyures. There are numerous fruit bats. New Guinea is richer in bird fauna than in any other form of animal life. The island’s 500 species include cassowaries, bower birds, birds of paradise, and parrots. There are many reptiles, particularly geckos, and skinks. Crocodiles inhabit the rivers.
Population. New Guinea is inhabited by several hundred ethnic groups belonging to the Melanesian race, mainly its Papuan branch. The majority of the population speaks the Papuan languages, which are genetically heterogeneous and fall into several groups. In certain regions various Austronesian languages are widely used. Most of the people have converted to Christianity (various Protestant denominations and Catholicism). Some of the inhabitants, however, have retained their traditional beliefs.
Historical survey. New Guinea was discovered in the first half of the 16th century by Portuguese navigators. The Russian scholar and traveler N. N. Miklukho-Maklai explored the island in the 1870’s and 1880’s. In the first half of the 19th century western New Guinea was conquered by the Dutch. (For the subsequent history of this part of the island seeWEST IRIAN.) In 1884, Great Britain established its rule over the southeastern part of the island, and in the early 20th century the area became an Australian colony and was renamed Papua. Germany proclaimed northeastern New Guinea a protectorate. In 1920–21, German New Guinea was transferred to Australia as a League of Nations mandate and renamed the Territory of New Guinea. In 1946 it became a UN trust territory, and later it was administratively united with the Papua colony by Australia. In late 1973, Papua New Guinea was granted autonomy.
Economy. A relatively small part of the island has been developed agriculturally. Yams, taro, cassava, corn, sweet potatoes, sugarcane, and bananas are raised, and the natives gather the fruit of the wild breadfruit, sago palm, and other plants. There are plantations of coconut palms, cacao and coffee trees, and rubber plants. Other economic activities include lumbering, oil drilling, fishing, and diving for pearls and trepang. The principal cities and ports are Sorong and Jayapoora in Irian Jaya and Port Moresby in Papua New Guinea.