The climate, relief and soil in Bangladesh create ideal growth conditions for many crops and tropical wet and monsoon forests. Information on the forested area varies. 10.2-17% and others are given as forested in the total land area. The natural vegetation has been largely reduced with the expansion of humans. Indications that exist in the remaining vegetation, are preserved in the soil, or about which plants grow in other regions with similar environmental conditions, can be used to derive what the natural vegetation in the whole of Bangladesh could be like. Elevations over ten meters above sea level would probably be predominantly forested by tropical evergreen mixed forest.
Water hyacinths are neophytes found in Bangladesh
The Department for Forests of the Government of Bangladesh classifies the forested areas today according to the respective location or dominant type.
- Evergreen, tropical forest in the southeast of the country, in the so-called Chittagong Hill Tracts (transliterated: Pārbatya Caṭṭagrām). This applies to the districts located there as Upazila(transliterated: upajelā) called Khagrachari (transliterated: KhāgꞋṙāchaṙi), Rangamati (transliterated: Rāṅāmāṭi), Bandarban (transliterated: BāndarꞋbān) and Cox’s Bazar (transliterated: KaksꞋb. Besides these, in the north-east of the country, in Sylhet (transliterated: Sileṭ), some regions are overgrown similarly. The dominant vegetation in these areas are tropical, evergreen or deciduous plants 5-60 m high, such as various types of two-winged fruit trees (transliterated eg: garjan), camp currents(transliterated: jārul), Gmelina arborea (transliterated: gāmār) or breadfruit trees (transliterated: cāpāliś ua), to which the jackfruit tree (jackfruit transliterated: kā̃ṭhāl) belongs. In particular, two types of forests exist side by side in the areas mentioned, depending on certain relief conditions. These are tropical rain-green wet forest and tropical rain forest. In addition, the largest proportion of the forested areas in the regions mentioned is secondary forest. The vegetation density varies greatly. In the course of shifting cultivation (transliterated: jum, jumꞋcāṣ) the new growth can become more species-rich after the end of one or more cycles of clearing, cultivation and possibly fallow land.
- Sal forest grows in some areas north of the capital Dhaka (transliterated: Ḍhākā) in the Upazila (see above) Gazipur (transliterated: Gājīpur), Mymensingh (transliterated: MaẏꞋmanꞋsiṃh), Tangail (transliterated: Ṭāṅgāil) as well as in elevated, drier areas in the west Bangladesh, a country located in southern Asia according to threergroup. These areas of tropical rain-green wet forest are dominated by deciduous sage trees(transliterated: śāl, śāl gāch, etc.) from the genus of the two-winged fruit trees. Over 70 species belong to the sage trees, not all of which grow in Bangladesh. Those that grow there can each have their own native or local names. This also reflects the importance of the sal tree as a useful wood. Its resin and its leaves are mainly used in medicine, its wood as a building material and generally in the local woodworking industry. Depending on the variety, the sal tree produces fatty fruits that are used in cosmetics, among other things.
- Reforestation areas are concentrated in the coastal areas to the Bay of Bengal, especially in the southwestern part of the country. The government of Bangladesh has started reforestation projects, often in international cooperation,since 2000 at the latest. Trees are supposed to serve as soil erosion protection and protection for residents in the event of natural disasters. The most common are different species of mangroves (transliterated collective term: sundarī / sundꞋrī (gāch)).
- Natural mangrove forest of the Upazila Khulna (see above). These areas in the southwest on the coast to the Bay of Bengal are part of the mangrove forest known as ‘Sundarban’ (transliterated: SundarꞋban). This continues in India. The Bangladeshi and larger part of the Sundarban received World Heritage status in 1997 by the United Nations Organization for Education, Science and Culture (abbr.: UNESCO). Halophytes, plants with a high tolerance to an increased salinity in the water, dominate this area, in which brackish water partially covers the ground all year round. These conditions are in particular different 5-35 m high mangrove species (see above) as well as some mahogany species (transliterated: e.g. paśur gāch), Rhizophora or Avicennia plants adapted. All of the latter are also considered mangroves, which do not represent a systematically uniform genus. Instead, ‘mangrove’ is a collective term. They belong to different plant families. The fact that the Sundarbans are characterized by high biodiversity and represent a retreat for many animal species threatened with extinction contributed to the decision to award the world natural heritage status. For this, the are Bengal tigers (transliterated: mostly Bāgh), the South Asian river dolphin or the Irrawaddy dolphin (both transliterated: Sisuk, śuśuk) counted.
- Freshwater swamp forest in northeastern Bangladesh, in the Sylhet region. These forest areas are flooded during the rainy season. Dominant plants are therefore adapted to dry winters and wet summers, e.g. Indian oak(transliterated: hajal (gāch)), Indian beech (transliterated: karac (gāch)) and others.