Biodiversity Evs 4w65o

Biodiversity Loss and Conservati on

MADE BY:

AISHWARYA GROVER BBS 1A 14015

What is Biodiversity? Biodiversity or Biological diversity is a term that describes the variety of living beings on earth. In short, it is described as degree of variation of life. Biological diversity encomes microorganism, plants, animals and ecosystems such as coral reefs, forests, rainforests, deserts etc. Biodiversity also refers to the number, or abundance of different species living within a particular region. It represents the wealth of biological resources available to us. Biodiversity has three essential elements: 

Genetic diversity: Genetic



Species diversity: This refers to the

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Ecosystem diversity: It is the

diversity is the variation in genes that exists within a species

variety in species or the living organisms.

diversity of ecosystems, natural

communities and habitats. In essence, it’s the variety of ways that species interact with each other and their environment.  Recently a new aspect has also been added- Molecular diversity.

Loss of Biodiversity In general, loss of biodiversity in a region may lead to (a) decline in plant production, (b) lowered resistance to environmental perturbations such as drought and (c) increased variability in certain ecosystem processes such as plant productivity, water use, and pest and disease cycles. While it is doubtful if any new species are being added (through speciation) into the earth’s treasury of species, there is no doubt about their continuing losses. The biological wealth of our planet has been declining

rapidly and the accusing finger is clearly pointing to human activities. Some examples of recent extinctions include the dodo (Mauritius), quagga (Africa), thylacine (Australia), Steller’s Sea Cow (Russia) and three subspecies (Bali, Javan, Caspian) of tiger. The last twenty years alone have witnessed the disappearance of 27 species. Adding to the grim scenario of extinctions is the fact that more than 15,500 species worldwide are facing the threat of extinction. Presently, 12 per cent of all bird species, 23 per cent of all mammal species, 32 per cent of all amphibian species and 31per cent of all gymnosperm species in the world face the threat of extinction.

What threatens our Biodiversity?

There are several threats that can lead to the loss of Biodiversity: 1. Habitat loss and fragmentation is considered by conservation biologists to be the primary cause of biodiversity loss. Clearance of native vegetation for agriculture, housing, timber and industry, as well as draining wetlands and flooding valleys to form reservoirs, destroys these habitats and all the organisms in them. In addition, this destruction can cause remaining habitats to become fragmented and so too small for some organisms to persist, or fragments may be too far apart for other organisms to move between. 2. Invasive alien species are the second greatest threat to biodiversity worldwide. Whether introduced on purpose or accidentally, non-native species can cause severe problems in the ecosystems they invade, from affecting individuals to causing huge changes in ecosystem functioning and the extinction of many species. Apart from the risks to human health, alien species inflict massive economic costs to agriculture,

forestry, fisheries and other human activities. For e.g. The Nile perch introduced into Lake Victoria in east Africa led eventually to the extinction of an ecologically unique assemblage of more than 200 species of cichlid fish in the lake

3. Pollution is currently poisoning all forms of life, both on land and in the water, and contributing to climate change. Any chemical in the wrong place or at the wrong concentration can be considered a pollutant. Transport, industry, construction, extraction, power generation and agroforestry all contribute pollutants to the air, land and water. These chemicals can directly affect biodiversity or lead to chemical imbalances in the environment that ultimately kill individuals, species and habitats.

4. Climate change, brought about by emissions of greenhouse gases when

fossil fuels are burnt, is making life uncomfortably hot for some species and uncomfortably cold for others. This can lead to a change in the abundance and distribution of individual species around the globe and will affect the crops we grow, cause a rise in sea levels and problems to many coastal ecosystems. In addition, the climate is becoming more unpredictable and extreme devastating events are becoming more frequent.

5. Over exploitation by humans causes massive destruction to natural ecosystems. Exploitation of biodiversity occurs for food (e.g. fish), construction (e.g. trees), industrial products (e.g. animal blubber, skins), the pet trade (e.g. reptiles, fish, orchids), fashion (e.g. fur, ivory) and traditional medicines (e.g. rhino horn). Selective removal of an individual species can unbalance ecosystems and all other organisms within them. In addition, the physical removal of one species often harms other (e.g. fishing by-catches)

6. Human populations are growing at an exponential rate, resulting in the problems above. There are more than 7 billion people in the world, and although natural disasters, disease and famines cause massive human mortality, we are getting better at surviving and the population just keeps growing. Human population numbers tripled in the twentieth century and although growth is slowing, one estimate predicts it will take until the twenty-third century for them to level out at around 11 billion.

CASE STUDY URBANISATION OF KOLKATA AND ITS IMPACT ON THE SUNDARBANS

The Sundarbans, which lies around 100 km to the south-east of Kolkata in the 24- Paraganas District of West Bengal, is formed by the confluence of Pa, Brahmaputra and Meghna rivers. Spread over an area of 9,600 sq. km., Sundarbans is bound by the

Ichamati–Raimangal Rivers in the east, Hooghly River in the west, Bay of Bengal in the south, and Dampier–Hodges line in the north. The most prominent feature of Sundarbans is the ubiquitous mangrove forests, which s for 85 per cent of all mangrove forests found in India. Champion (1936) classified Sundarbans as moist tropical seral forests, comprising of beach and tidal forests. In of biodiversity, Sundarbans serves as an important refuge for several endangered and threatened mammals including the tiger (Panthera tigris), smooth-coated otter (Lutrogale perspicillata), and great Indian civet (Viverra zibetha). The region also has several smaller predators such as the jungle cat (Felis chaus), fishing cat (Prionailurus viverrinus), and leopard (Prionailurus bengalensis). It is home to over 150 avian species. In of floral diversity, Sundarbans consists of 64 plant species In recognition of its high biodiversity and the occurrence of endangered and threatened

species, the Sundarbans was designated as a UNESCO World Heritage site in 1987. However, urbanisation of Kolkata and its neighbouring areas have had severe impact on the Sundarbans. Construction of various infrastructure and increasing demand for natural resources from the city and its neighbourhood have led to large scale deforestation of mangroves, siltation and pollution. FARAKKA BARRAGE AND SUNDARBANS The Farakka barrage project, taken up for augmenting the navigational status of the Kolkata port in 1975, has brought significant increase in the freshwater discharge in its distributaries. As a result, the rivers in the eastern sector have lost connection with the Ganga–Bhagirathi system in the course of time and are now fed only by the tide. This has resulted in significant changes in the fish diversity. Studies by Dhaneesh and Kumar (2010) argue that the western sector of the Sundarbans showed the presence of more economically important fish species, while the eastern sector was populated with the commercially insignificant varieties. The study attributed the variations in fish diversity to ingression of seawater and the resultant increase in salinity that led to reproductive failures and increase in mortality due to loss of primary food supply.

Many studies show pronounced ecological change is occurring in Sundarbans due to

unprecedented discharge of untreated domestic and industrial effluents carried by the tributary rivers, as well as disposal of contaminated mud from the Haldia Port Complex, a major oil disembarkment terminal in eastern India. The delta has become susceptible to pollutants like organochlorine, pesticides, polychlorinated biphenyls, polycyclic aromatic hydrocarbons and heavy metals. These pollutants are slowly changing the estuary's geochemistry and affecting the local coastal environment

Importance of Biodiversity/ Why should we conserve Biodiversity? Biodiversity is extremely important to people and the health of ecosystems. A few of the reasons are:  Biodiversity allows us to live healthy and happy lives. It provides us with an array of foods and materials and it contributes to the economy. Without a diversity of pollinators, plants, and soils, our supermarkets would have a lot less produce.

 Most medical discoveries to cure diseases and lengthen life spans were made because of research into plant and animal biology and genetics. Every time a species goes extinct or genetic diversity is lost, we will never know whether research would have given us a new vaccine or drug.  Biodiversity is an important part of ecological services that make life livable on Earth. They include everything from cleaning water and absorbing chemicals, which wetlands do, to providing oxygen for us to breathe—one of the many things that plants do for people.  Biodiversity allows for ecosystems to adjust to disturbances like extreme fires and floods. If a reptile species goes extinct, a forest with 20 other reptiles is likely to adapt better than another forest with only one reptile.  Genetic diversity prevents diseases and helps species adjust to changes in their environment.

 Simply for the wonder of it all. There are few things as beautiful and inspiring as the diversity of life that exists on Earth.

Conservation of Biodiversity There are several strategies which are adapted for conservation of Biodiversity. Some of these are:

1.

Legislation

Formal policies and programs for conservation and sustainable utilisation of biodiversity resources dates back to several decades. The concept of environmental protection is enshrined in the Indian constitution in articles 48a and 51a(g). Major central acts relevant to biodiversity include: • Environment Protection Act, 1986 • Fisheries Act, 1897 • Forest Act, 1927 • Forest (Conservation) Act, 1980 • Wildlife (Protection) Act 1972 and Wildlife (Protection) Amendment Act 1991

The various Central Acts are ed by a number of state laws and statutes concerning forests and other natural resources. Some of them are: National Forest Policy amended in 1988, National Conservation Strategy and Policy Statement for Environment and Sustainable Development, National Agricultural Policy, National Land Use Policy, National Fisheries Policy, National Policy and Action Strategy on Biodiversity, National Wildlife Action Plan and Environmental Action Plan.

2.

In-situ Conservation

Conserving the animals and plants in their natural habitats is known as in situ conservation. The established natural habitats are: • National parks and sanctuaries • Biosphere reserves • Nature reserves • Reserved and protected forests

• Preservation plots • Reserved forests The first such initiative was the establishment of the Corbett National Park in 1936. National Parks are highly protected by law. No human habitation, private land holding or traditional human activity such as firewood collection or grazing is allowed within the park. Sanctuaries are also protected but certain types of activities are permitted within these areas. Biosphere Reserves are another category of protected areas. Under this, a large area is declared as a Biosphere Reserve where wildlife is protected, but local communities are allowed to continue to live and pursue traditional activities within the Reserve. The Government of India has set up seven biosphere reserves: Nokrek (Meghalaya), Nilgiri (Kamataka, Kerala, Tamil Nadu), Namdapha (Arunachal Pradesh), Nanda Devi (Uttar Pradesh), Sundarbans (West Bengal), Great Nicobar (Andaman & Nicobar Islands), Gulf of Mannnar (Tamil Nadu).

Several special projects have also been launched to save certain animal species which have been identified as needing concerted protection effort. These projects are designed to protect the species in situ. Project Tiger, Project Elephant, Save the Barasingha campaign are examples of this initiative.

3.

Ex-situ Conservation

Ex-situ conservation of plants and animals preserve means to protect them away from their natural habitat. This could be in zoological parks and botanical gardens or through the forestry institutions and agricultural research centres. A lot of effort is under way to collect and preserve the genetic material of crops, animal, bird and fish species. This work is being done by institutions such as the National Bureau of Plant Genetic Resources, New Delhi, the National Bureau of Animal Genetic Resources, etc. Reintroduction of an animal or plant into the habitat from where it has become extinct is another form of ex situ conservation. For example, the Gangetic gharial has been

reintroduced in the rivers of Uttar Pradesh, Madhya Pradesh and Rajasthan where it had become extinct. 4.

Community Participation

It is being recognized that no legal provisions can be effective unless local communities are involved in planning, management and monitoring conservation programmes. There are several initiatives to do this, both by government as well as non-governmental organizations. For example, the t Forest Management philosophy stresses involvement of village communities in regenerating and protecting degraded forest land in the vicinity of villages. Successful conservation strategies will have to have the confidence and participation of the local communities.

BIBLIOGRAPHY www.vigyanprasar.gov.in www.wikipedia.org

www.conserve-energy-future.com www.nwf.org www.wwfindia.org

MADE BY: AISHWARYA GROVER BBS 1A 14015