II.

Land and Resources

Bangladesh, a low-lying country traversed by numerous rivers, has a coastline of about 580 km (360 mi) along the Bay of Bengal.

A.

Natural Regions

Most of Bangladesh lies within the broad delta formed by the Ganges (Ganga), Brahmaputra, and Meghna rivers and is subject to annual flooding. Much fertile, alluvial soil is deposited by the floodwaters. Most of the land is exceedingly flat and low-lying. The only significant area of hilly terrain, constituting less than one-tenth of the country’s territory, is the Chittagong Hill Tracts District in the narrow southeastern panhandle of the country. There, on the border with Myanmar, is Mowdok Mual (1,003 m/3,291 ft), the country’s highest point. Small, scattered hills lie along or near the eastern and northern borders with India. These areas, which receive among the heaviest rainfall in the world, provide the headwaters of the Meghna and its tributaries. The eroded remnants of two old alluvial terraces—the Madhupur Tract, in the north central part of the country, and the Barind, straddling the northwestern boundary with India—attain elevations of about 30 m (100 ft). The soil here is much less fertile than the annually replenished alluvium of the surrounding floodplain.

A huge tract of mangrove swamp, the Sundarbans (Sunderbans), lies along the coast of Bangladesh and West Bengal between the estuaries of the Meghna and Hugli (Hooghly) rivers. The Sundarbans extends about 274 km (170 mi) along the Bay of Bengal and about 100 km (62 mi) inland. It contains a vast number of tidal rivers and innumerable islands, but very little development or agriculture.

B.

Rivers

Rivers are a prominent and important feature of the landscape in Bangladesh. The country includes about 200 navigable rivers. Two of South Asia’s largest rivers, the Ganges and Brahmaputra (locally known as the Jamuna), flow into Bangladesh, where they join to form the Padma. The Padma merges with the Meghna southeast of Dhaka; the combined rivers then empty into the Bay of Bengal. In the dry season other deltaic distributaries that lace the terrain to the west of the Meghna may be several kilometers wide as they near the Bay of Bengal, whereas at the height of the summer monsoon season they coalesce into an extremely broad expanse of silt-laden water. In much of the delta, therefore, homes must be constructed on earthen platforms or embankments high enough to remain above the level of all but the highest floods. In nonmonsoon months the exposed ground is pocked with water-filled borrow pits, or tanks, from which the mud for the embankments was excavated. These tanks are a chief source of water for drinking, bathing, and small-scale irrigation.

C.

Climate

The climate of Bangladesh is of the tropical monsoon variety. In all areas about 80 percent of the annual rainfall typically occurs in the monsoon period, which lasts from late May to mid-October. Average annual precipitation ranges from about 1,400 mm (55 in) along the country’s east central border to more than 5,080 mm (200 in) in the far northeast. In addition to the normal monsoonal rainfall, Bangladesh is subject to devastating cyclones, originating over the Bay of Bengal, in the periods of April to May and September to November. Often accompanied by surging waves, these storms can cause great damage and loss of life. The cyclone of November 1970, in which about 500,000 lives were lost in Bangladesh, was one of the worst natural disasters of the 20th century. Tornadoes, which also accompany the monsoon season, can cause devastation as well.

Bangladesh has warm temperatures throughout the year, with relatively little variation from month to month. January tends to be the coolest month and May the warmest. In Dhaka the average January temperature is about 19°C (about 66°F), and the average May temperature is about 29°C (about 84°F).

D.

Plant and Animal Life

With the exception of the Chittagong Hill Tracts District, portions of the Madhupur Tract, and the Sundarbans, few extensive forests remain in Bangladesh. The forested and wooded area amounts to about one-eighth of the country’s total land area. Broadleaf evergreen species characterize the hilly regions, and deciduous trees, such as acacia and banyan, are common in the drier plains areas. Commercially valuable trees in Bangladesh include sundari (a type of mangrove for which the Sundarbans is probably named), gewa, sal (mainly growing in the Madhupur Tract), and garyan (in the Chittagong Hill Tracts District). Village groves abound in fruit trees (mango and jackfruit, for instance) and date and areca (betel) palms. The country also has many varieties of bamboo.

Bangladesh is rich in fauna, including 109 indigenous species of mammals, 295 types of birds, 119 kinds of reptiles, 19 different amphibians, and 200 varieties of marine and freshwater fish. The rhesus monkey is common, and gibbons and lemurs are also found. The Sundarbans area is one of the principal remaining domains of the endangered Bengal tiger; although the tiger is officially protected, illegal poaching is known to occur. Herds of elephants and many leopards inhabit the Chittagong Hill Tracts District. Other animals living in Bangladesh include mongoose, jackal, Bengal fox, wild boar, parakeet, kingfisher, vulture, and swamp crocodile.

E.

Natural Resources

With the exception of natural gas, the mineral endowment of Bangladesh is meager. Vast reserves of natural gas—both onshore and offshore in the Bay of Bengal—have been discovered in Bangladesh since the mid-1990s. Total proven reserves amount to 142 trillion cu m (5 trillion cu ft), but actual reserves may be much greater. Natural gas is the principal energy resource in Bangladesh and an important ingredient in the manufacture of nitrogenous fertilizers. Other natural resources include a coalfield in the northwest and large peat beds that underlie most of the delta. Limestone and pottery clays are found in the northeast.

F.

Environmental Issues

Waterborne diseases such as cholera are a serious threat to public health in Bangladesh. Until the 1970s, many of Bangladesh’s people became sick from drinking polluted water drawn from surface rivers. Aid agencies such as the United Nations Children’s Fund (UNICEF) built shallow wells throughout the country to help provide a safe source of drinking water to Bangladesh’s poor. In the 1990s, however, it was discovered that many of these wells were contaminated by arsenic, a poison that occurs naturally in Bangladesh’s alluvial soils. In 1998 the World Bank granted Bangladesh a $32.4 million credit to identify contaminated wells and develop alternative sources of safe drinking water. UNICEF, the World Health Organization (WHO), and other international agencies joined efforts with the government to address the problem. About 30 percent of the wells tested have been contaminated to some degree by arsenic. The health problems associated with arsenic poisoning are compounded by the lack of access to health care in many rural communities.