Haor

A haor (Bengali: হাওর) is a wetland ecosystem in the north eastern part of Bangladesh which physically is a bowl or saucer shaped shallow depression, also known as a backswamp. In a country where one third of all area can be termed as wetlands, the haor basin is an internationally important wetland ecosystem, which is situated in Sunamganj, Habiganj and Moulvibazar districts and Sylhet Sadar Upazila, as well as Kishoreganj and Netrokona districts outside the core haor area. It is a mosaic of wetland habitats, including rivers, streams and irrigation canals, large areas of seasonally flooded cultivated plains, and hundreds of haors and beels. This zone contains about 400 haors and beels, varying in size from a few hectares to several thousand hectares.

In Bangladesh, which lies in the floodplain of three great rivers, the Bengali language has several terms to differentiate between lakes, including baor, haor, jheel and beel. All four are types of similar freshwater wetlands. The word haor is a regional variation derived from the Bengali word sagor meaning sea. In parts of Bangladesh, people often pronounce the Bengali alphabet স (sa) as হ (ha), and sometimes গ (ga) as হ (ha). Thus, sagor has become haor.

The line of difference between an haor, a beel and a baor is usually very thin. A beel is usually a depression or topographic low generally produced by erosion or other geographical process. These are generally smaller and seen all over Bangladesh. These are marshy in character. Sometimes beels are remains of a river that has changed its course. Many of the beels dry up in the winter but during the rains expand into broad and shallow sheets of water, which may be described as fresh water lagoons. Beels are generally smaller than haors, but there also are large beels like Chalan Beel in Rajshahi Division, through which the Atrai River passes. It has shrunk over the years but still occupies an area of 26 km² in dry season. Sometimes small permanent water bodies within the haors remain after the haors dry up. These are also called beels, which occupy the lowest part of the depressions.

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