bio-diversity of Bangladesh

bio-diversity of Bangladesh

By dr.fourkan Ali

The Convention on Biological Diversity 1992, defined "biological

diversity" as the variability among living organisms from all sources including, inter alia, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part. This includes diversity within species, between species and of ecosystems. Bio-diversity literally means the diversity of the earth’s life forms.

Thus, biodiversity includes the varieties, races, and species of all rnicrobes, plants and animals including their genetic differences, i.e.,, the gene pool of each species that live on the earth. Mankind or any living species cannot survive alone on this earth. They are dependent on other lives surrounding them for food, clothing, shelter, health, medicare, and other life support systems. The continued existence of all living beings including man is thus dependent on the existence of a rich bio-diversity.

Bio-diversity is measured in terms of number of kinds and their population in a given area. The first refers to "species diversity". The second includes the different varieties and races within a species and thus constitutes the "genetic diversity".

A community of organisms does not live and operate in a vacuum. It operates in an environment. This environment is composed of both living (biotic) and nonliving (abiotic) parts, the community of organisms can cause changes in the environment and the environment can also affect the community. The community plus the environment with which it interacts is referred to as an "ecological system" or in short “ecosystem”.

Differences in bio-diversity the distribution of the life forms is not similar due to the climatic and ecological differences in different geographical regions of the earth. Each particular ecosystem sustains a particular life form and has to adjust and adapt all the time to the changing conditions of the environment. In the long term, this leads to specialisation, or the development of new species, i.e. evolution through changes for adaptation to changed circumstances with the passage of time. Virgin areas on the earth are invaded everyday as a result of swelling human population. New areas are being encroached upon to meet human needs. Thus, various ecosystems are loosing their bio-diversity continually due to human activities and interference, this is endangering the probable future survival adaptations of many species. It is often said that the poor people are responsible for environmental degradation. Contrary to popular belie that poor are causing environmental degradation, they are often found to be well aware of the need for resource conservation. In many developing countries, over exploitation of natural resources and inequity in access to these resources are seen as the causes for environmental degradation.

Poverty results from resource constraints. To secure the present and the future of mankind against the onslaughts of environmental degradation, all development efforts should be made sustainable, ensuring that the resources are not totally exhausted but are able to regenerate and continue to exist At the same time, conservation measures should be adopted so that at least a part of the ecosystem with their original bio-diversity can continue to evolve.

Ecosystem of Bangladesh: Most of Bangladesh terrain is alluvial with some hilly areas on its northern and esteem flanks. The landmass is crises-crossed by innumerable rivers, rivulets and canals. Although most of the plain land have been converted into crop fields, yet the land may be divided into several divisions whose micro-environment, vegetation and fauna are somewhat different form each other.

Some of these terrestrial ecosystems are as follows:

(i)      Alluvial plains

(ii)      Hilly areas with evergreen forests in the southeastern Chittagong

           Hill tracts, greater Sylhet, Netrokona and Sherpur districts

(iii)     Mangrove forests of the Sundarbans, Chakoria and Teknaf

(iv)     Deciduous forests of Sal and other mixed species in the high land of                                                                                                                                                                                                                                                                                                                                                                                                                               the Madhupur Tracts and Gazipur-Narshingdi area

iv)      The uplands of the Barind 'Tract

(vi)     Undulating terrain in the northern Tentulia-Panchagar areas

          with acid soil

(vii)    Coastal islands and the coral reefs of the St. Martin's Island

(viii)   Chars on the riverbeds

(ix)     Recently accreted polder-land in the coastal regions in the south

Other Aquatic ecosystems are:

(i)      The Bay of Bengal within Bangladesh territory

(ii)      Estuarine zones of the river systems

(iii)     Freshwater zones of the river systems _

(iv)     Beels: swampy land in the dead channels of former rivers

(v)     Haors: tectonic depressions in the dead channels of former rivers

(vi)     Baors or oxbow lakes in the moribund rivers

(vii)    Ponds

(viii)   Borrow pits

(ix)     lakes

Diversity of species: The geographical position and climate of Bangladesh is very favorable for the growth and development of many plants and animals. However; a proper inventory of the flora and fauna of Bangladesh is being prepared by a number of academic institutions including IUCN.

Plant spedm: Bangladesh is rich in bio-diversity. It has diverse fisheries and aquatic life. The country has one of the world's largest tidal flood mangrove forests in its southwest seaboard. There are more than 1000 paddy varieties, 5000 plant varieties -» of which 33 are rare or threatened. There are some 350 bird species of which 27 are threatened,

At least S000 species of flowering plants are found in Bangladesh, many of them have economic importance, the main crops are rice, wheat, jute, sugarcane, tea, cotton, tobacco, millets, pulses, potato, oil seeds, yarn and numerous species of vegetables. Among fruits -- jackfruit, mango, banana, litchi, coconut, cashew nut, pineapple, guava, melon, water melon, date palm, black berry papaya, etc, are common.

The hill wilderness are examples of tropical rain forest with tall canopy of woody trees and an undergrowth of bamboo, Many plants and herbs have medicinal value, The inland deciduous forests contain mainly trees like sal, jackfruit and other species. Plantation of teak, rubber mahogany eucalyptus, tropical pine, oil palm and other valuable timber and fire wood now forms a major part of the managed forests of Bangladesh. The mangrove forests provide sundari, goran, gewa, golpata and firewood of miscellaneous species. Golpata and sun grass are important economic plants used for roofing o the rural houses. Bamboo is exploited for domestic and industrial use.

Animal spam: Bangladesh has possibly the richest inland fisheries in the world. It still has more fish species than all of Europe combined -- up to 500 of them including the close offshore river dependent species.

A total of about 500 fish varieties, 19 amphibians, 124 kinds of reptiles and 125 mammalian species have been recorded in Bangladesh. In addition to these, many species of insects and other invertebrate animals are also found.

Marine Animals: There are several coral reefs in the St Marten’s Island in addition to the common shore forms like sea pen, sea torch and jelly fishes. Several species of shrimps are also found in the Bay of Bengal.

Estuarine fauna: Around 149 species of fin fish, 19 species of shrimps and prawns, several crabs, snakes and dolphins` are found in the estuarine waters of Bangladesh, The brackish water crocodiles are seen in the Sundarbans estuary.

Freshwater fauna: Freshwater in Bangladesh contains some 260 species of fin-fishes. During the last three decades, several exotic lishes have been introduced in the country and according to some experts; many of those are adversely affecting the indigenous fish varieties.

State of biodiversity in Bangladesh: Population explosion has led to overexploitation of the natural resources, affecting the country's ecosystems adversely and depleting their bio-diversity and gene pool.

The exact quantification of this depletion is not possible due to the absence of any institutional organization to monitor those changes.

Nevertheless, attempts may be made to assess generally the extent of these depletions on the basis of the various ecosystems.

Forest ecosystems: The total forest area has been reduced to about 4-6% of the total area from over 15% in the last several decades. Already 34 plant and 156 vertebrate animal species are under severe threat of extinction; 12 mammals, 4 kinds of birds and one reptile species are reported to have become extinct from Bangladesh. The main reasons for the loss of bio-diversity of the forest ecosystems of Bangladesh may be summed up as follows.

(i)      Encroachment of forest land for agriculture and human settlement

(ii)      Practice of Jhum cultivation by the tribal people in the CHT

(iii)     Indiscriminate felling of trees and thereby reducing tree cover due to unholy alliance between the forest officials and timber merchants

(iv)     Over-exploitation of particular resources, like medicinal plant, bamboo, canes, etc.

(v)     Salinity intrusion due to reduced freshwater flow in the Ganges

system in the Sundarbans

(vi)     Destruction of the mangrove forests of Chakoria and Teknaf for

raising shrimp farms

Aquatic ecosystem: The wetlands with their bird fauna and the fisheries resources of the open water fisheries are also under severe threat. Some of the reasons are:

(i)      Human interference such as flood control embankments, drainage systems and conversion of wetland into crop land have reduced the water area, prevented or altered the seasonal migratory routes of many fishes and birds and reduced natural stocking of fishes in many water bodies

(ii)      Construction of unplanned roads and homesteads on wetlands

(iii)     Increased salinity intrusion in the coastal areas due to lower water flow in the dry season

(iv)     Pollution from domestic, industrial and agrochemical waste products and their rtm-off

(v)     Hunting, trapping and disturbances to aquatic birds

(vi)     Management of open water fisheries through auction; ineffective legal Instruments for the protection of fishes, etc.

Crops: The number of local varieties of different crops is steadily dec ining due to promotion (on economic consideration) of only a few selected varieties, specially of the HYV of rice and wheat; and more recently due to introduction of genetically modified organisms. This is musing ineparable lox of the genetic diversity of our crop plants and their wild relatives, The reasons are as follows:

(i)      Lack of adequate conservation efforts to maintain and protect indigenous crop genetic resources

(ii)      Lack of software for the conservation and propagation of tl-re various local crop varieties

(iii)     Unbalanced competition between the local varieties consequent to the introduction, adoption and promotion of the exotic and locally developed I-[YV crops.

Domestic animals and birds: The population of domestic animals and birds of Bangladesh is insufficient to meet the basic minimum requirements of draft power meat, milk and eggs. The resource base declined steadily consequent to the human population explosion. The reasons are:

(i)      Gradual encroachment of the fallow gazing lands to grow agricultural crops and thereby reducing e base for grass and fodder "UPS

(ii)      Regular, almost annual, recurrence of epizootic diseases of cattle and poultry in some parts of the country

(iii)     Long absence of any concern for the production of fodder crops and animal feed in the country even to the extent of exporting animal feed ingredients like oil cakes -

(iv)     Wrongful dependence on artificial insemination from imported breeds of bulls for improving the cattle stock since 1940s --though without any visible success

Convention on Bio-diversity Bangladesh scenario: Bangladesh has signed the Convention on Bio-diversity [CBD] in 1992 and as a signatory to the Convention; the country is pledge-bound to implement the Convention at the national level. The Convention has provision for both in-situ and ex-situ conservation of bio-diversity One of the best ways of biodiversity conservation is to protect segments of a particular ecosystem so that the various species living in them are preserved in situ. The protected areas maybe of different kinds, e. g., wildlife sanctuary; game reserves; national parks; fish parks; coral reef parks, etc..

As a signatory to the Convention, Bangladesh needs to develop an Action Plan for the conservation of its biodiversity in the Convention, there are measures to conserve bio-diversity establish protected areas, integrate bio-diversity conservation in national plans and policies and protect traditional cultural practices. Some initial activities in implementing the Bio-diversity Convention in Bangladesh have begun. We have the Forestry Policy 1994 and a Z0-year Forestry Master Plan [1993-20131. presently, a number of bio-diversity projects in the forestry sector are being implemented by the Ministry of Environment and Forest with support from the Asian Development Bank (ADH) and Global Environment Fund (GEF). Notably among them, is the bio- diversity conservation project in the Sundarbans.

With assistance from the UNDP the Ministry of Environment and Forest under its Sustainable Environment Management Programme [SEMP] is currently implementing a number of pilot projects for conservation of bio-diversity in Bangladesh. Notably among them are the community based Haor and Floodplain Management protect in the partially degraded wetlands in Sunamganj and at two sites at jamuna-Brahmaputra and Madhumati floodplains, IUCN, Nature Conservation Movement CNRS and BCAS are together implementing the projects. CARITAS, a local NGO, has a project for sustainable resource management in brackish water areas in the south-western part of Bangladesh. Barind Multipurpose Development Authority [BMDA], an agency under the Ministry of Agriculture, is addressing ecosystem management in the Barind areas presently under creeping desertification in the north-western part of Bangladesh; Under SEMP the Ministry is also preparing an Environmental Action Plan for the Chittagong Hill Tracts (CHT) in south-eastern parts of the country. The Action Plan, among other things, is intended to address depletion of bio- diversity and forest resources in the CHT through a number of pilot projects there.

The county has a long way to go in respect of implementing the Convention on Bio-diversity in Bangladeshi Along with the government initiatives, the civil society bodies, professional groups and NGOs have also been active in this regard. The NGOs with help from local people have embarked on a massive plantation programme across the country. And it is noteworthy that today different environmental activist groups have been more conscious that ever before about the importance of protecting the country’s bio-diversity, People have understood tl1e need for sustaining a rich bio-diversity not only for their own survival but also for the survival of their progeny.