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Thursday, September 30, 2010

Greenpeace- India releases Safe Food Guide

Greenpeace today released the Safe Food Guide version 2.0 that ranks 25 of the most popular food companies which hold a major share of the market in India. Based on their responsibility towards Indian consumer on the GM food issue, the Guide categorizes companies as green, yellow and red.
Dabur and KRBL emerged as the top green/ companies while Nestle, PepsiCo, Haldiram and Hindustan Unilever Ltd among others faired poorly to find themselves on the red/list.

The current and long term policies of these companies on the use of genetically modified organisms (GMOs), their willingness to inform their position to consumers and proactiveness in ensuring a labelling and liability regime on foods derived from GM crops, were the main parameters used in this guide.

On the basis of these factors each company was assessed.

The Red list include companies like Nestle, Pepsico, Cargill, Hindustan Unilever Ltd , Britannia, Godrej Hersheys Ltd., Haldirams, MTR, Parle Biscuits Pvt. Ltd., Agrotech, Surya Foods, Amul, GSK, FieldFresh (Bharathi Enterprises] and Kelloggs. These companies have not taken any concrete steps to provide Indian consumers with GM free food for now or in future thereby being irresponsible.

Green list companies include Dabur India, KRBL Ltd. whose flagship product is India Gate rice and Vippy Industries .These companies have not only taken necessary steps to ensure that they remain GM-free now and in future but also are ready to engage with the government and relevant industry associations to keep the Indian food market free from GM food.

Yellow list companies include popular brands like Cadbury's, ITC, Ruchi Soya, LT Foods, Heinz India, Bambino Agro and Kohinoor Foods Ltd., which have said that that they are committed to sourcing ingredients that are GMO-free but are yet to take a long-term position on being GM free or share their position with the consumers.

“Even though Bt brinjal, the first GM food crop reaching commercialiation stage has been put on a hold owing to public opposition across the country earlier this year, there are field trials for over 11 crops across the country, and imports of raw materials such as corn, canola and soya all of which threaten to contaminate the food supply chains.” said Shivani Shah, Sustainable Agriculture Campaigner,Greenpeace India

The brands in the guide have been listed after a 3-month long process of direct communication with them. The final categorisation of companies into green, yellow and red is based on the response of these brands to this detailed process.

The Safe Food Guide is the only tool available in India for the consumers to know how responsible is their favourite food brands in providing them GM free food. The guide is also available for consumers in handy pocket size versions at Mother Earth Stores across the country. Buyers in Karnataka can get the smaller version also at Fab India stores in Karnataka. An online version is available at www.safefoodnow.org

“The growing consumer rejection of GM foods makes it the responsibility of food companies to not only adopt long-term GM-free policies but also share this information with consumers through various media,” Shah said.

The Guide also highlights consumer attitudes towards GMOs in India. In 2010, in a consumer opinion poll conducted by GfK Mode,

  • Over half of the citizens questioned in India (53%) said they would reject food brands containing GMOs.
  • A majority (77%) have shown a preference for foods that come from ecologically grown sources.
  • 69% want packaged food to declare through labeling whether or not it contains genetically modified organisms.
  • 61% people want labeling on raw fruits, vegetables etc. and unpackaged foods as well.

It’s evident that food brands operating in India have a long way to go to in terms of providing consumers with a choice of GM free food . Greenpeace demands that food businesses pay heed to consumer demands and adopt a No GM policy at the company level and engage with government to keep the Indian market free from GM food.

source:Text taken from the Geenpeace

Monday, September 27, 2010

Alarming level of solid waste pollution in Ranchi

A tourist to Ranchi, travelling in train is supposed to be attracted by the natural beauty and undulating topography of the plateau of Jharkhand. But, no sooner than he comes out of Ranchi junction and starts moving through city streets he has to pas through a number of heavily polluted areas efficient enough to convert the previous images in his mind into a distracting collage of images of solid waste and decaying things.

The Central Pollution Control Board in its latest release has pointed towards 47lakh 72 thousand and 720 tonnes of solid wastes and 11 lakh 73 thousand 840 million polluted and contaminated water in the form of liquid waste released into the environment of Ranchi every year. Out of all the solid waste produced here in a year, about 18lakh 27 thousand tonnes remains disposable, about 25 lakh 46 thousand tonnes remains recyclable, and about 2 lakh 36 thousand of waste remains unfit for any treatment other than incineration.

Here in Ranchi no one has ever seen any solid management option for the disposal of hazardous and other types of solid waste. A plant for the treatment of bio- medical waste is lying useless since 2008. A biomedical waste treatment plant has been found functional in Jamadoba area. As such, the condition of pollution in Ranchi due to solid waste and even due to liquid waste is very grim and alarming.

Experts are of the opinion that most of the people living in the city area lack civic sense. Most of the drains and sewerages in the city have no destinations. Under this condition the solid waste dumped into drains remain decomposing all the time releasing unpleasant smell to intoxicate the air. Earlier, a non-government organization worked for some years by adopting door-to-door collection method. But it too left the work as no dump yard in the nearby area was ever allotted to it for dumping the waste collected by its volunteers from door-to-door. The NGO used to charge a minor fee from every household, and the same too was not acceptable to many family heads who argued that the same was the responsibility of the Municipal Corporation. Though the Municipal Corporation has upgraded its various systems during the last two or three years, it has not been able to ensure proper sanitation due to lack of sufficient number of safai karmacharies. On the other hand citizens tend to put each and every responsibility on the government and very few initiations towards cleanliness have ever been taken up by civilians living in the city. With the prevailing plastic culture, it is rather harder to infuse civic sense in the public having the habit of throwing all the solid waste in plastic carry bags on roads, into drains, and even towards the gates of houses of other people. If the system of waste management has never been formed on the community level, how can anyone say about its failure?

Currently, the employees of the Municipal Corporation are on strike owing to their different demands. No alternate arrangement has ever been made, and now it is feared that the community health may be risked by the spread of some of the diseases like dengue, malaria, etc due to the gradual decay of the accumulated waste. As per the national standard, one person is required for cleaning 500 meter length of a road or a stream, but in Jharkhand not a single worker is employed even to clean 5000 meter length of a road or a drain. Under these conditions people of a particular area should organize mohallah- committees and should carry on periodic sanitation drive in their localities.

Key Words: solid waste,tourist, topography, Jharkhand,Central Pollution Control Board,dengue, malaria, national standard, drain, mohallah committee

Sunday, September 26, 2010

Jungle of Ricinus communis

Ricinus communis, a plant of immense medicinal and economic importance is growing luxuriantly in the waste lands of U.P. ,Jharkhand and Bihar like an invasive species.

Runoff from paddy fields causing growth of aquatic plants in village ponds

... a case of Eutrophication?



Wednesday, September 15, 2010

Individual efforts for protection of environment and sustainable development

Committed individuals of all ages and nationalities find their own ways to help save the environment, all over the world. A number of people have worked on individual levels for the protection and preservation of environment. Many of these individuals remained always concerned with the process of modern development and pointed out its negative impacts on environment and its components. These people advocated strategies for sustainable development and inspired many people across the world. Further efforts of these people took the shapes of different movements that shook the world and enforced to think seriously about the protection and preservation of the environment in different parts of the world.

We have numerous examples of individuals who dedicated their lived for the sake of environment and all the living beings including human race. Here is an example of a young girl Sophie, 14, who stood fast and is still working against whaling activities of Japan. She went to the court together with her father for her protest outside Japanese Embassy in London. The British Press Association reported on Jan. 25, 2008- A 14-year old, British Girl has been arrested after protesting against whaling, outside the Japanese Embassy in London. “It is very important subject at the moment. They are such amazing creatures and they deserve rights and love and a bit of respect.” Sophie Wyness said to the British Press Association. Sophie had previously campaigned against Australia’s Nuclear Policy. She, along with her sister Ruby and Father Mr. Martin Wyness, was arrested for environmental action related to Global Warming when they staged the protest putting face masks on two figures from the Terracotta Army in the British Museum during October 2007.

Hiroshi Nakatsuji, a comedian and stage artist, uses the stage as anti-whaling platform, in his show “Lucky Golden Whales”. Many Actors and actresses of Hollywood also, have been working on individual basis for the protection and preservation of environment since early 1990s. About 100 environmental activists from Loss Angeles “stormed an Indonesian freighter bringing rain forest wood to the major studios” (Hollywood Reporter, Apr.22, 2008). A number of Indian films and stage actors and actresses have been suggesting the public on print and electronic media to preserve and protect environment.

Film Producers like Jacques Cousteau and David Attenborough have made documentaries on several endangered species of animals so as to stimulate sense of conservation among masses. Zoo 2000, Expedition to the Animal Kingdom, and Earth Watch etc. are names of some programmes designed to generate awareness and to contribute to the sustainable development. Here are some more examples of individual efforts for the protection of environment, conservation of natural resources and sustainable development. These efforts have been responsible for the origin of environmental movements in different parts of the world-
The earliest known writings concerning environmental pollution in the Middle East were Arabic Medical Treatise that was written during the “Arab Agricultural Revolution”. Authors of these writings were Alkindus, Costa ben Luca, Rhazes, Ibn Al- Jazzar, al-Tamimi, al-Masihi, Avicenna, Ali ibn Ridwan, Issac Israeli ben Soloman, Abd-el-latif, and Ibn- al- Nafis. The writings of these authors incorporate air-contamination, water contamination, soil contamination, mishandling of solid waste, and environmental assessment of certain localities.

In 1272, King Edward I of England banned the burning of sea-coal after its smoke had become a problem. However, the ban could not be successful and its smoke continued to pollute environment till the Great Smog of 1952 came to make history.

In the U.S. efforts for environment started in 1739 when Benjamin Franklin and residents of Philadelphia petitioned the Pennsylvania Assembly to stop dumping of waste and to remove tanneries from the Philadelphia’ Commercial District.

The individual efforts and philosophies of John Muir, and Henry David Thoreau in 1800s, made great contributions to the cause of protecting the natural resources of the west. Thoreau’s book entitled Walden has strong arguments that people should become intimately close with nature. John Muir (1838-1914) was America's most famous and influential naturalist and conservationist. He is one of California's most important historical personalities. He has been called "The Father of our National Parks," "Wilderness Prophet," and "Citizen of the Universe.

Muir collected like minded people concerned with the study of ecology and geology and formed the Sierra Club on May 28, 1892, in San Francisco, California; with the motto of Explore, Enjoy and Protect the planet.
According to the Sierra Club, “As a wilderness explorer, he( John Muir) is renowned for his exciting adventures in California's Sierra Nevada, among Alaska's glaciers, and world wide travels in search of nature's beauty. As a writer, he taught the people of his time and ours the importance of experiencing and protecting our natural heritage. His writings contributed greatly to the creation of Yosemite, Sequoia, Mount Rainier, Petrified Forest, and Grand Canyon National Parks. Dozens of places are named after John Muir, including the Muir Woods National Monument, the John Muir Trail, Muir College (UCSD), and many schools……. The International Astronomical Union (IAU), through the Smithsonian Astrophysical Observatory's (SAO) Minor Planet Center (MPC), has announced the naming of a newly discovered minor planet in honor of pioneer conservationist John Muir. The announcement was made in the June 2006 issue of the Minor Planet Circular, published by the SAO/MPC. This development seems an appropriate tribute for someone who gave his address as "Earth-Planet, Universe!"

1. The growth of Environmental protection and preservation continued up to the 20th century and efforts for the protection of wildlife started in full swing. The endangerment of American Bison and the death of the last Passenger Pigeon shook many of the American people and in 1916 the National Park Services were started by the president Woodrow Wilson.

2. Aldo Leopold published A Sand Country Almanac in 1949 which explained his belief that mankind should have moral respect for environment and “that it is unethical to harm it”. This book by Aldo Leopold is considered to be the most influential book in the field of sustainable development.

3. The American Biologist Rachel Carson authored his famous book “The Silent Spring”, which was published in the year 1962 by Houghton Miffin.”The book catalogued the environmental impacts of indiscriminate spraying of DDT in the United States and questioned the logic of releasing large amounts of chemicals into the environment without fully understanding their effects on ecology or human health. As a result of putting such serious philosophies into air, the public concern rose upto such extent that the United States Environmental Protection Agency was formed in 1970.The agency put sufficient pressures to ban the DDT in the United States in 1972.

Let me quote a few lines from the Silent Spring for you –
"There was a strange stillness. The birds, for example – where had they gone? Many people spoke of them, puzzled and disturbed. The feeding stations in the backyards were deserted. The few birds seen anywhere were moribund; they trembled violently and could not fly. It was a spring without voices. On the mornings that had once throbbed with the dawn chorus of robins, catbirds, doves, jays, wrens, and scores of other bird voices there was now no sound; only silence lay over the fields and woods and marsh."

Rachel Carson (1907-1964) was a scientist, writer, naturalist and, many say, the mother of the environmental movement; and B. her Book: the Silent Spring- the Bedrock of the modern environmental movements. Here is a list of the books authored by Rachel Carson- 1941-Under the Sea Wind; 1943-Food from the Sea: Fish and Shellfish of New England; 1944-Food from the Sea: Fish and Shellfish of the South Atlantic; 1951- The Sea around Us; .955 - The Edge of the Sea; 1962 - Silent Spring; 1965- The Sense of Wonder (posthumous).

After the Silent Spring, some other books were also published which had immediate and obvious influence on the public opinion. These books were- “The Quiet Crisis” (1963) by Stewart Udall; “Before Nature Dies” (1965) by Jean Dorst; “On the shred of cloud” (1966) by Rolf Edberg etc.

4. The NASA scientist James Lovelock published his book entitled Gaiya: A New look on life on earth. According to Gaiya Hypothesis of James Lovelock, life on earth can be understood as a single organism.
Now the environmentalism has grew upto such serious points like climate change, the Global Warming, and the Depletion of Ozone Layer on different levels. Besides peoples’ movements against big dams, mega projects, displacements etc. are growing in India and in many other parts of the world.

The Goldman Awards to Individuals for Environment
In the world, six people are awarded Goldman Environment Award every year to encourage common people to the cause of environment. The Goldman Environment Award is compared to the Nobel Prize in the field of environment. These awards were set up by an American rich man in 1990, and since then these awards are being given on April 16, in San Francisco. It was strange co-incidence that Wangari Maathai of Kenya received Nobel Prize in 2004 after receiving the Goldman Environment Award in 1991. You may want to know for what she received these honors of the highest degrees? Well, Wangari Maathai of Kenya had started the Green Belt Movement to recreate forests. So far four Indians have been able to receive these prestigious awards for environment. These four Indians with their brief introduction are mentioned below-

§ Medha Patkar: She is the first Indian to receive the Goldman Award for Environment. She fought for the cause of more than three lakh tribals who were displaced due to submergence of their villages when the huge Sardar Sarovar Dam was built across the Narmada River. For the cause of displaced tribals she was put in prison many times, the Narmada Bachao Andolan (NBA) she had started continues even today.
§ Rashida Bee and Champa Devi: These ladies are recognized due to their fight for the good of Bhopal Gas Victims.

§ M. C. Mehta: He is a lawyer from Delhi. He is famous for his legal battle to save the Taj Mahal from getting damaged by industrial emission.

Key Words: Sophie, Silent Spring, Goldman, Narmada, Rashida Bee, Champa Devi, M. C. Mehta

Sunday, September 12, 2010

Ozone Layer: Its depletion, consequences, and protection

Ozone is an unstable blue gas having pungent odour. Chemically, it is an allotrope of Oxygen which is an element in the gaseous form. It has three oxygen atoms in its single molecule and in the language of Chemistry; its molecular formula is 03. It is used as a powerful oxidant, bleach, and water purifier. It is also used to treat industrial wastes.

Where is ozone found?
If found in the troposphere; ozone acts as a powerful pollutant. But, when found in the stratosphere, it acts like a friend of the earth because it shields most of the ultra violet radiations and does not allow them to pass on towards the same. In stratosphere, it is found in the form of a dense layer called as the Ozone Layer or the Ozone Belt. Thus, the Ozone Belt in the stratosphere acts like a Protective Umbrella of the earth. Let us see, how this gas is formed in the atmosphere.

How is ozone formed?
Ozone is formed in the stratosphere when oxygen molecules Photo dissociate after absorbing an UV Photon of shorter wavelength(less than 240 nm) to produce two oxygen atoms. Ozone is mainly produced from oxygen containing molecules such as Sulphur dioxide, Nitrogen Oxides, etc. also when these molecules are exposed to ultraviolet radiations. In Chemistry, a molecule is the particle of any substance that can remain in a free state. But, what is an atom? Well, an atom is the smallest particle of a substance that can not usually remain in a free condition. Two or more atoms combine to form a molecule. Through the foregoing lines, we came across another term, allotrope. One of the two or more different forms of molecules of an element is called as an allotrope.
A large number of ozone molecules assemble around the earth to form the Ozone Layer which extends from 13 to 48 km above the earth surface. On an average, it is about 230 Dobson units (DU) in thickness. DU is the unit which measures thickness of the ozone layer. It equals to 0.01 mm.

Ozone depleting substances
Chlorofluorocarbons (CFCs or Freons), Methane, Nitrous Oxides (N2O), Carbon Tetrachloride (CCl4), Methyl Bromide (a soil fumigant and insecticide), aircraft emissions, n- propyl bromide and Halon- 1202 are major agents that cause depletion of ozone layer. Hence, these are called as Ozone Depleting Substances (ODS).
How is the Ozone Layer Depleted?
Chlorofluorocarbons or Freons get accumulated in greater amounts at high altitudes and gradually reach to the stratosphere. Under the influence of intense short wave ultraviolet radiations they release chlorine atoms. A single chlorine atom can react with more than, 100,000 molecules of ozone and can convert them into oxygen. Other ozone depleting substances like methane, nitrous oxide, methyl bromide etc. too, pass through a series of reactions under the influence of UV-radiations of sunlight and catalysts found in the air and help in the depletion of ozone layer.
• Ozone molecule absorbs UV light between 310 and 200 nm. The ozone molecule absorbs oxygen atom to form two molecules of Oxygen, and the Ozone cycle continues.
• Ozone is destroyed by a number of free radicals catalysts –like Hydroxyl radical, Nitric oxide radical, and Bromine through natural and anthropogenic sources.

Effects of the Depletion of Ozone Layer

I. General Effects
Ozone absorbs ultraviolet radiations so that much of it is never allowed to reach to the earth surface. The protective umbrella of ozone layer in the stratosphere protects the earth from harmful ultraviolet radiations. Ozone plays an important role in the biology and climatology on the earth’s environment. It filters out all the radiations that remain below 3000Å. Radiations below this wavelength are biologically harmful. Hence any depletion of ozone layer is sure to exert catastrophic impacts on life in the biosphere. The Ultraviolet radiation is one of the most harmful radiations contained in the sunlight. Ozone layer in the stratosphere absorbs these radiations and does not allow it to reach to the earth.

The depletion of Ozone layer may lead to UV exposures that may cause a number of biological consequences like Skin Cancer, damages to vegetation, and even the reduction of the population of planktons (in the oceanic Photic zone).

Some of the remarkable effects of the UV radiations or the effects of depletion of the Ozone Layer are mentioned below.

(1) UV radiation causes sun- eye- diseases (cataract), skin diseases, skin cancer and damage to immune system in our body.

(2) It damages plants and causes reduction in crop productivity.

(3) It damages embryos of fish, shrimps, crabs and amphibians. The population of salamanders is reducing due to UV-radiations reaching to the earth.

(4) UV- radiations damage fabrics, pipes, paints, and other non-living materials on this earth.

(5) It contributes in the Global Warming. If the ozone depletion continues, the temperature around the world may rise even up to 5.5 Celsius degrees.

II.Specific Effects

The specific effects of depletion of Ozone Layer have been observed on Human Society, Agriculture, Plants and Animals etc. These effects have been summarized as below-

A. Effects of Ozone Depletion on Human Society

(i).The flux of ultra violet radiation in the biosphere is increased due to ozone depletion. It has seriously harmful effects on human societies like formation of patches on skin and weakening of the human immune system.

(ii). It may cause three types of skin cancer like basal cell carcinoma, squamous cell carcinoma and melanoma. A 10 per cent decrease in stratospheric ozone has been reported to cause 20 to 30 per cent increase in cancer in human society. Each year, about 7000 people die of such diseases each year in USA. About 10 percent increase in skin cancer has been reported in Australia and New Zealand.

(iii).Exposure to UV radiations damages skin of the sun-bathing people by damaging melanocyte-cells or by causing sun-burns due to faster flow of blood in the capillaries of exposed areas.

(iv).Exposure to UV radiations due to ozone depletion may cause leukemia and breast cancer.

(iv).Exposure of UV radiation to human eye damages cornea and lens leading to Photo keratitis, cataract and even blindness.

(v).The Ambient Ozone Exposure may cause Emphysema, bronchitis, asthma and even obstruction of lungs in human beings.

(vi).Exposure to radiations due to ozone depletion has been reported to cause DNA breakage, inhibition and alteration of DNA replication and premature ageing in human beings.

B. Effect of Ozone Depletion on Agriculture
(i). Radiations reaching to the earth due to ozone depletion cause severe damage to plants including crops. As per reports, ultra violet radiations reaching to the earth cause losses up to 50 per cent in European countries.

(ii).The radiation reaching to the earth due to the depletion of the ozone layer cause visible damages in plants. They adversely affect the rate of photosynthesis that finally results into decrease in the agricultural production.

(iv).The UV radiation enhances the rate of evaporation through stomata and decreases the moisture content of the soil. This condition adversely affects the growth and development of crop plants and reduces the crop yield.

(v). The ozone reduction adversely affects the weather pattern which in turn affects the crop production by encouraging plant injuries and disease development.

(vi). The UV radiation reaching to the earth surface alters the global balance between radiation and energy. This condition of imbalance causes seasonal variations that further reduce the crop production.

(vii). A number of economically important plant species such as rice, depend on cyanobacteria residing in their roots for the retention of nitrogen. These bacteria are sensitive to UV light and they are hence, are killed instantly.

C. Effects of Ozone Depletion on other Plants and Animals
(i).The ozone layer depletion causes climatic alterations that cause physiological changes in plants and animals. The change in the energy balance and radiation may affect the survival and stability of living organisms.

(ii).The depletion of ozone layer may cause changes in thermal conditions of the biosphere. It may affect type, density and stability of vegetation which in turn may affect different bio-geo-chemical cycles operating in nature. Interruption in these cycles damages important process of ecosystem leading to dangerous conditions for plants and animals.

(iii).The depletion of ozone layer causes death of plankton- populations in fresh as well as marine waters .This condition seriously affects the transfer of materials in ecosystems. The recent researches gave analyzed a widespread extinction of planktons 2 million years ago that coincided with the nearby supernova. Planktons are particularly susceptible to effects of UV light and are vitally important to the marine food webs.

The Ozone Hole
The hole in the context of ozone depletion relates to thinning of the ozone layer in a certain area. Here, the word hole is considered as a hole in the ground which in the context of ozone layer is thinning of ozone in a certain area up to certain depth as measured by scientists. In fact, ozone hole is an area where the ozone concentration drops to an average of about 100 Dobson Units. The word ‘Dobson’ has been taken from the name of the famous scientist and climatologist G. M. B. Dobson, who observed the ozone hole for the first time in 1956, over Halley Bay.

The satellite measurements done in September 2000 revealed that the thinning of ozone layer in Antarctic had reached a record 28.3 million sq km which was about one million sq km greater than the record of 1998. Thinning of ozone in such a big area is rightly termed as ozone hole. The ozone hole in the Northern Latitudes has also been recorded. The ozone hole over Antarctica may expose not only the Antarctica but also a large area of the pacific and Atlantic oceans and South America as well.

The ozone hole over Antarctica was first discovered by Farman, Gardiner and Shanklin in 1985. They jointly declared their findings through a paper published in the May issue of Nature (an important International Journal) in 1985. The entire scientific community was shocked to know their findings.

On the basis of observations made through a network of ground based Dobson Spectrophotometer, an International Panel of scientists confirmed that the Ozone Layer was being depleted at all latitudes out side the tropics. Out of a big group of scientists across the world, Crutzen, Molina, and Rowland were awarded the Nobel Prize in Chemistry for their work on Stratospheric Ozone, in 1995.The scientific assessment of ozone depletion is going on across the world since 1981, under the sponsorship of the United Nations Environment Programme (UNEP), and the most recent measurement was done during the year 2006. Here are the comparative pictures showing the Ozone Holes over Antarctica during the spring seasons of two different years.

Why is the Ozone Hole over Antarctica, usually formed during spring months?

A circulation pattern of gases traps the ozone over the South Pole for several months but not during winter. This circulation pattern is called as Antarctic Polar Vortex. Within this vortex, the substantial ozone loss was detected for the first time during 1980. During extreme cold conditions, the polar winters are dark and continue up to three months without solar radiations. This leads to the decrease in temperature. The polar vortex traps air and contributes in further falling temperature which goes down up to -80 0c. The low temperature forms cloud particles that contain nitric acid and ice. These clouds provide surfaces for chemical reactions that lead to ozone depletion. During the Antarctic winters and springs, reactions that take place on the surface of the Polar Stratospheric Clouds (PSCs) convert pollutants into free radicals such as Cl and ClO.

These clouds can also remove NO2 from the atmosphere by converting it to nitric acid. It prevents the newly formed ClO from being converted back into ClONO2. The role of sunlight is the fundamental reason why the Antarctic ozone depletion is greatest during spring. The Antarctic ozone depletion is caused during September to early December. Over 50 per cent of the lower stratospheric ozone is destroyed during the period of the Antarctic Spring.

Prevention and Control of Depletion of the Ozone Layer
Banning the production and use of ozone depleting substances is one important way of preventing further depletion of the ozone layer in the stratosphere. On the other hand, alternatives to these chemical compounds should also be searched out so as to replace these chemicals. Scientists of the University of California, U.S.A. devised a possible way of plugging the ozone hole by injecting alkanes or propanes into the atmosphere of Antarctica. The alkanes have the affinity of reacting with ozone destroying chlorine atoms. According to the scientists, about 50,000 tones of alkane or propane would have to be blown to check the ozone loss. These chemicals could be released from an altitude of about 15 km by a group of hundreds of large aircrafts.

Global Efforts for Controlling the Depletion of the Ozone Layer
Since ozone depletion is a Global Environmental Problem, it requires strong global efforts and co- operations for its solution. The International Community is taking up strong efforts as a result of which global consumption of ozone depleting substances has decreased markedly.
Following the UNEP’s Governing Council’s meeting to co- ordinate activities on protecting ozone layer in 1975, United States, Canada, Norway and Sweden banned the use of CFCs. The production capacity of the European Union (E U) was frozen allowing limited uses of aerosols. In March 1985, 28 countries of the world agreed on Vienna Convention for the protection of the ozone layer. In September 1987, different countries of the world adopted Montreal Protocol on substances that deplete ozone layer. The General Assembly of the United Nations voted to designate September 16 as the World Ozone Day, to mark the signing of the Montreal Protocol, the 16th September, 1987.By December 2001, 182 countries ratified the Vienna Convention and 181 the Montreal Protocol. By 2000, 96 chemicals were subject to control under the Montreal Protocol.

Friday, September 10, 2010

Cyperus:vulnerable species accumulating together in a single habitat

Family Cyperaceae  has a number of plants known by different names, and often confused for one another but the destruction of habitats and changes in climate are forcing these species towards extinction, much before any clear and confirmed understanding about their roles in ecosystems and their values in ethnoherbology, traditional healthcare systems, and researches.