Causes of Biodiversity Depletion in Bangladesh and Their Consequences on Ecosystem Services

Abstract

Bangladesh is exceptionally endowed with a vast variety of flora and fauna due to its unique geophysical location which are maintaining balance ecosystem. There are recorded 5,700 angiosperms, 68 legumes, 500 medicinal plants, 29 orchids and 1,700 pteridophytes. Sundarban is a rich faunal diversity in Bangladesh which mammals 113, birds 628, reptiles 126, amphibians 22, 708 fishes, insects 2,493, mites 19, alges 164 and 4 species of echinoderms. Bangladesh’s inland water bodies are known to be the habitat of 266 species of indigenous fish, 13 exotic fish, 56 prawns, about 26 freshwater molluscs, and 150 birds. The marine water bodies (200 nautical miles along the coast) are also remarkable for being habitat of 442 species of fish. There are at least 36 species of marine shrimps. About 336 species of molluscs, covering 151 genera have been identified from the Bay of Bengal. In addition, several species of crabs, and 31 species of turtles and tortoises, of which 24 live in freshwater, are found in Bangladesh. A total of 168 seaweeds, 3 sponges, 15 crabs, 3 lobsters,10 frogs, 3 crocodiles, 24 snakes, 3 otters, 1porcupine, 9 dolphins, and 3 species of whale found in Bangladesh. About 70 bees, many species of wasps and 8-10 per cent of the land area is under good canopy cover. A total of 81 fish species were recorded from Chalan Beel including 72 indigenous fish species and nine exotic species. More than 85 percent of Modhupur forest has been cleared in last 40 years. In most of the areas the age of sal forest is not more than 10 to 15 years. Thousands prawn farms have replaced almost the Chokoria mangrove forest. Thousands prawn farms have replaced almost the entire forest. The Chokoria Sundarbans today- the evergreen forests have been replaced by thousands of shrimp ponds. Two orders of class Oligochaeta of phylum Annelida: five families, nine genera include fifteen species of Tangail District of Bangladesh. A total of 35 species of earthworms have been recorded in Bangladesh. Already, 12 wildlife species have become extinct from Bangladesh. In addition, Mammals 40, birds 41, reptiles 58 and amphibians 8 have listed in red data book of threatened animals of Bangladesh. Anthropogenic pressures, uncontrolled dredging, hydrological intervention, pollution, chemical fertilizers are directly effect on habitat, biodiversity and aquifer. In this article, the causes of depletion of biodiversity and the consequences on ecosystem services were observed.