Wetlands: Biodiversity and livelihood values and significance with special context to Bangladesh

Abstract

Wetlands provide various ecosystem goods and services to humans. Rice, the staple food of about 50% of global population and consumed at the rate of one-fifth of the total global calorie count, is grown in wetland systems. The total area of wetlands in Bangladesh is about 7-8 million ha, which constitutes about 50% of the land surface of the country. Wetlands of Bangladesh encompass haors (freshwater marshes of bowl or saucer-shaped shallow depression), baors (oxbow lakes - dead arms of a river), beels (saucer-shaped deeper part of the floodplain landscape), fishponds and dighi (large ponds), flooded rice lands and floodplains, natural lakes, man-made reservoirs (Kaptai Lake), and coastal (Sundarbans) and marine (St. Martin's Coral Island) areas. Wetlands are rich in flora and fauna (300 plant species, 400 vertebrate species, and 260 freshwater fish species are dependent on wetlands of Bangladesh). Some wetlands of Bangladesh are of national and international significance such as Tanguar haor (Ramsar and an Ecologically Critical Area), Hakaluki haor (Ecologically Critical Area), Sundarbans (Ramsar and UNESCO World Heritage Site and Ecologically Critical Area), and St. Martin's Coral Island (Ecologically Critical Area). About two-thirds of people in Bangladesh depend on wetlands for a variety of purposes including water (drinking, irrigation), food production (agriculture, aquaculture), fishing, livestock grazing, bird hunting, fire-/fuelwoods, medicinal plants, wild food, honey, waterway transportation, harvesting grasses and seaweeds, and tourism/recreational business. Some poorest of the poor in the vicinity depend totally on the goods and services of the wetland for livelihood. Apart from biodiversity and livelihood support, wetlands have additional significances as a source and sink for greenhouse gases and in mitigation of disasters in Bangladesh. Livelihood diversification, awareness, and education of local communities on preservation and conservation of wetlands would be needed to reduce pressure on wetland resources.