Threat to migratory flocks
by C. M. Kumbhkarni
THE change in environment has been causing parasitism in the migratory flocks of sheep and goats, and consequent heavy losses to the migrant tribes — Gaddis and Gujjars.

Cybersurfing with Amar Chandel

Science Quiz from J. P. Garg

New products & discoveries

Polythene: an environmental disaster
by Anubha Kaushik

HUNDREDS of new products are appearing in the market every day, which are dramatically proliferating into the common man’s life. Polythene is one such product, which due to its ease of use, hardiness, light weight, waterproof nature and low cost has found a wide applicability in modern society. It is largely used for packaging and storing and is most widely used as carry-bags. As the consumption of polythene has increased enormously, so has the accumulation of waste polythene, particularly in urban areas! Polythene bags lying in garbage heaps and blowing here and there has become a common sight today at most of the public places, residential colonies, tourist complexes etc., which not only is an eye-sore but also has serious environmental implications.

Polythene is non-degradable in nature in the sense that it is not degraded easily and will take hundreds of years to degrade. Chemically, polythene is a polymer of ethylene of high molecular weight. It is a thermoplastic material which when heated gets softened due to weakening of intermolecular forces and melts. On cooling it solidifies again.

The main problem with polythene is associated with its non-degradable nature which raises the question regarding its disposability. After using the consumables contained within the polybags, the latter are just thrown away. Being light in weight, they blow away with wind and reach the drains and often cause blockage of sewage and flooding of streets, much to the discomfort of the public who themselves are the causative agents of such problems. It is a common practice to pack up the household trash in polybags and throw it away. Hardly do we realise that by doing so we are not even allowing the biodegradable kitchen-waste to get decomposed freely in the soil by microbes or even allowing the same to be eaten by animals!

Quite often cows and stray animals try to tear open the polybags in search of food and get injured by broken glass, blades, pins etc. contained therein, because very few of us ever care to segregate these materials from the kitchen waste. In a national seminar on protection and preservation of animals it was reported that 60% of the stray cows die, due to consumption of polythene bags. Five cows were choked to death at Jaipur due to blockade of their digestive tract following consumption of polythene bag. An eye-opening news item in The Tribune, (Feb. 4, 98) highlighting “287 foreign bodies inside a cow” was sensational enough to reveal to us what deadly injury we are causing to these helpless creatures which otherwise are worshipped by all Hindus as “Mother”! 48 kg of polythene and 287 foreign bodies were taken out by the veterinary surgeons Dr Kulvinder Singh and Dr Bhupinder Singh of Jammu Univ. from two cows. The Jammu & Kashmir Animal Husbandry Department has cautioned that the urban cattle population is facing a great threat from discarded polythene bags. The polythene bags ingested by the cows harm the animals in two ways, according to the veterinary scientists of C.C.S. Hisar Agricultural University. The ingested polythene hinders the process of fermentation and mixing of contents leading to indigestion. They also obstruct the orifice between reticulum and omassum or between pyrolus and true stomach. If not removed by operation, the outcome can be just fatal. The scientists of the Veterinary Department of H.A.U., Hisar come across 25 such cases every year, on an average, and strongly believe that there are much larger numbers of stray animals which after consuming polythene simply end up in death.

Dumping the polythene bags in the ground is also not an environmentally-sound approach due to their non-degradable nature. Mechanical shredding of polythene reduces the fertility of soil as the shreds get mixed up with the soil particles. Similarly, burning of polythene is harmful as it releases toxic gases like dioxins which have ill effects on health. Thus, it is not safe to throw, dump or even burn the polythene. Then what is to be done with it? The junk-dealer can help us in this regard, because he is an eco-friendly man who helps recycle most of our junk.

Most of the polythene are brightly coloured. Toxic chemicals or binding agents like lead and cadmium are added to the polythene. Some times, colour may get pinched off from it which affects the food stuff kept in it and causes toxic effects. Red and Yellow coloured polythene are especially harmful.

Small children are to be given more cautious protection against the abuse of polythene. Besides preventing them from putting polythene in the mouth, they must be warned not to put masks of such bags while playing. Non-porous polybags lead to accidental choking in many children.

Polythene waste has also become a major nuisance at sea-shores where tourists leave heaps of the poly bags. Many sea-animals are choked due to ingestion of such polythene wastes. Sea turtles often mistake multi coloured poly bags as jelly-fishes and as they ingest them, their intestines are blocked and metabolism is impaired. Thus, polythene has become a threat to the wild-life.

The consumption pattern of polythene shows that while 85% of the common people use upto 15 polythene bags per week, the use is upto 300 polythene bags per week in 50% of the shopkeepers and more than 500 polythene bags per week in about 40% of the shopkeepers. Maximum use of polythene is as multipurpose carry-bag for carrying fruit and vegetables, grocery item etc. while 18% of the population use it for packaging purpose. According to this survey although 80% of the population is well aware about the fact that polythene is not degradable, about 90% of the population knows that polythene can cause clogging of drains while 50% of them have actually experienced the problem a number of times in their own locality and about 12% are fully aware about the whole range of harmful effects caused by polythene, yet the attitude of the people regarding disposal of polythene is very discouraging 50% of the population just throws away the discarded polythene while 8-10% burn it and 10-12% of the people act wise enough to give it to the junk-dealer who sells it to the recycling plant. In fact, most of junk dealers also do not like to take this light-weight polythene junk which becomes too bulky. Consequently, the polythene waste is not disposed off in an eco-friendly manner. The people of Hisar are, however, interested in switching over to alternatives of polythene for carrying articles 30% of the masses show interest in cotton bags, 27% in paper bags, 24% in jute bags while a minor fraction of 4% is not willing to replace polythene since they are of the opinion that there is no substitute for polythene. A major proportion of population reuses the polythene bags once, twice or three times, whereas there are others who use the same bag repeatedly until it is destroyed.

The shopkeepers who are the major consumers of polythene are not to be blamed for their low environmental consciousness regarding polythene. In fact, they find the paper bags costly and the customers expect the shopkeepers to provide polythene bags for all the articles they purchase. Consumer acceptance is reduced if they do not provide polythene bags. Thus, there is an urgent need for attitudinal change in all sections of the society. Each individual matters a lot. The Himachal Pradesh Government has taken a wise step to put a ban on the use of polythene bags in all its towns and hill stations. Haryana has also put a ban on littering of polythene which has hardly brought any results. The polythene problem cannot be tackled in such piecemeal style. Rather, a nationwide adoption of such a strategy is required so that the use of polythene is minimised, if not completely banned.

Recently, there are reports of development of bio-degradable polythene making use of corn-starch. Till such times that we are able to substitute the non-degradable polythene by a degradable counterpart, the 3R’ golden rule that must be followed is Reduce, Reuse, and Recycle the polythene. When each one of us pass on this message to ones neighbours, friends and relatives, the cascading effect would be seen in the society which is required for the safety of our cattle, wild-life, crops, our own selves and our environment as a whole. Transformation of our throw-away, easy going mentality is required for solving the polythene menace.

The writer is from the department of environmental sciences, G.J. University, Hisar.

Environment
Threat to migratory flocks
by C. M. Kumbhkarni

THE change in environment has been causing parasitism in the migratory flocks of sheep and goats, and consequent heavy losses to the migrant tribes — Gaddis and Gujjars.

Animal husbandry has been a reliable source of income for the people of Himachal Pradesh, living in the higher hills and in the mountain locked backward and tribal areas. Gaddi and Gujjar tribes have been mainly dependent on sheep and goat rearing. These tribes, every year, come down to the plains during the winter months (winter pasture) along with their sheep and goats, while they take advantage of lush green pastures in the summer months by reaching on the high peaks of temperate Himalayan regions where excellent grasses grow after the melting of snow.

Migration takes place upto 13,000 feet above the mean sea level of Lahaul and Spiti, Kinnaur, Dodra Kawar, Bharmaur and Bara Banghal of Himachal Pradesh. According to the shepherds, mortality in the flocks due to diarrhoea was one of the major menaces to their occupation. The average size of a flock per farm of these migratory livestock is about 245 consisting of nearly equal number of sheep and goats. Thirteen per cent of the flock get infected, and of these around 46 per cent die during their course of journey. Mortality in sheep is more in comparison to goats. The pattern of death is five to eight animals per week.

The animals show severe diarrhoea with emanciation, weakness, lethargy and anaemia and lastly succumb to the disease. According to Dr S. Mittra and Dr RK Agnihotri of Department of Veterinary Parasitology, Himachal Pradesh Agriculture University, Palampur, the death incidence was studied in retrospect to investigate the causes. The clinical examination indicated that animals had moderately high degree of anaemia.

According to faeces culture, “Haemonchus”, a nematode parasite, was observed as preponderant parasite, which was accompanied by another nematode viz “Trichostrongylus”, and a coccidium, “Eimeria ninakohlya Kimovae”. “Haemonchus” is well known as a voracious blood sucker, and this anaemia could be attributed to the “Haemonchus” worm, wherein the other parasites could be an additive factor.

The prevalent ambient temperature (March to June) and humidity in these migratory tracks like Una-Kangra-Darang-higher altitude areas, favour larvae growth and accumulation. These infested tracks are used consecutively by the groups of shepherds one after another, thereby leaving a risky pasture for the next.

Cybersurfing with Amar Chandel
Your own jukebox

Things have been getting easier and easier for music lovers down the years. There was a time when to enjoy good music, they had to go to the artiste for a live concert. Then came the radios and gramophone records. The old singers were aghast. How could they sing for just about anybody who had the money to buy their records? It was with great effort (and financial incentives) that the record companies made some good singers record for them. Then came the compact cassettes which could be re-recorded. Prophets of doom said that these would spell the end of music industry as we knew it. Nothing that drastic happened. In fact, there has been quite a boom in place of doom. Music is thriving like never before. Yet another revolution is “quietly” (pun intended) taking place. Now you don’t even have to have a record player or tape-recorder to listen to your favourite music. CD-quality music is there for the asking on the Net, in most cases free of cost. All that you have to do is to go to the site www.winamp.com and download a software called MP3 player. After that, your computer is as good as a jukebox on which you can play the music of your choice whenever you want it. Select any song from the wide array available and it can be played on your computer. What amazes one is the quality of reproduction. The controls that one normally finds in top-end machines are available in the MP3 player and one can really indulge one’s ears. That is the beauty of Internet. But that is only the beginning. Things are getting better and better day by day. In the works is Internet-2 which will be several hundred times faster than the existing one and the high bandwidth requirements of applications such as live video would be more easily tackled. Details about this wonderful tool can be obtained at www.internet2.edu.

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For years, Tomorrow’s World programme on BBC has been introducing today’s people to the great leaps forward in the various fields of science. Many of the prophesies they have made have come true. All these "believe or not" events can be assessed at www.bbc.co.uk/tw. Whenever I have time to spare, the site provides a wonderful opportunity to go beyond being up to date.

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Some readers are cross with us and have even accused us of providing “false information”. You will remember that last month we featured a site established by the Indian Army at www.armyinkashmir.com. This was set up to provide factual information about the situation in Kashmir. Mr Devinderpal Singh has written to us from New Jersey (USA) that when he visited the site it was full of propaganda by anti-India militants. He is absolutely right and I share his anguish. What he is perhaps not aware of is that the site had suffered a hacker attack last month, and was mutilated with impunity. The healthy sign is that the site has been fully restored and has now come back into the right hands.

This was taken over by someone with a Lahore number last month. Another unknown group commandeered it later. The material they loaded on to it was obviously taken from the pro-Pakistani sites.

The Army will have to ensure that it is not defeated similarly in future. There is a cyberwar going on out there and we have to win it, come what may.

Science Quiz
from J. P. Garg

1. Name the winners of the 1998 Nobel Prize for Chemistry. For which work have they won this most coveted international award?

2. This space hotel-cum-laboratory can pose a serious danger to human life by landing on inhabited areas when it ends its voyage in December, 1999. What are we talking about? In which year was this space station put into orbit?

3. Continuing on the subject, two space vehicles posed similar danger (but did not actually produce any harm) during 1991 and 1979. Name these two space vehicles.

4. ACT, a non-surgical treatment for the coronary heart disease, has recently come to India. What is the full form of ACT?

5. More than fifty thousand of these animals have been slaughtered on the Orissa coast during the last two years by the fishermen who use sharp weapons to kill these animals to save their fish catch and nets. Which animals are we talking about?

6. What is the science of transmitting and maintaining the quality of sound in theatres and halls called?

7. Name the Austrian monk and botanist known as the father of “modern genetics”. Which type of plants did he study to arrive at a famous law known after his name?

8. An artificial satellite can continue operating for a number of years. Which part of the satellite supplies energy to its various systems?

9. Name the strong but the lightest wood in the world, which weighs about half as much as cork and is particularly useful in ship-building.

10. “There was a cricketer of talent very bright

Who could bowl much faster than light

And before the batsman could score a run

The ball returned to his hand to everyone’s delight”.

Which theory does this limerick refer to? Which principle does it precisely convey?

ANSWERS

1. Briton John Pople and Austria-born American Walter Kohn Won, both researchers at US universities; for developing methods that can be used for theoretical studies of properties of molecules and the chemical processes in which they are involved. 2. Russian space station ‘Mir’; 1986 3. Soviet space station Salyut-7’; American space station “Skylab”; 4. Artery Clearance Therapy 5. Sea turtles (Olive Ridleys) 6. Acoustics 7. Gregor Johann Mendel; pea plants 8. Solar panel comprising solar cells 9. Balsa wood, obtained from a tropical American tree 10. Theory of relativity; Time reversal when something travels faster than light.

Electricity from drinking water
Swiss researchers have installed small hydropower stations in mountainous regions, which utilise high pressure of drinking water flowing down from high-level catchments to reservoirs at lower levels to generate electricity.

The mini power stations, developed by researchers of Sulzer Hydro AG, convert the potential energy of water, which is otherwise lost in pressure-breaking shafts and pressure-reducing valves, into electricity, reports Sulzedr Technical Review.

In the mountains, there is usually a difference in altitude of about 100-800 metres (m) between the catchment and reservoirs. This results in an increase in pressure, which gets reduced before the water is routed into the reservoirs.

Shafts and valves were employed earlier for reducing the pressure, but they did not utilise the hydraulic energy and cost high.

Sulzer Hydro has installed about 40 of these small power stations in the last few years having an average annual production of about 19 million kWh of electricity. If this energy were produced with fossil fuels (bituminous coal), it would result in the emission of 19,000 tonnes of CO2.

To protect the drinking water, the housing, intake and pipework can be made of stainless materials. Electric servomotors and water hydraulics replace oil hydraulics. Coatings suitable for use with drinking water protect against corrosion. The bearings are lubricated with biodegradable oils and greases.

The major part of the infrastructure – the water catchment and building of the drinking-water supply system – being already available, economically beneficial tiny installations with outputs from 15 kW upwards are not far off.

Plant extract to combat diseases
Russian researchers have come up with an oral plant extract that can be used against various afflictions.

The extract called Topivit, prepared from topinambour (Jerusalem artichoke) tubers, enhances immunity, blood formation, wound healing, growth of beneficial bacteria in the intestine and helps in diabetes control, says RIA Novosti.

The advantages of Topivit over conventional medicines is that being plant-based, it does not show side-effects like allergy, can be taken orally with food, and works well with children.

Researchers say topinambour, a rich source of vitamins, minerals and sugars, helps keep the body’s systems in top gear by restoring energy and boosting immunity.

Studies carried out at the Institute of Immunology the Russian Academy of Medical Sciences among children susceptible to diseases have shown positive results-after a fortnight. About 80 per cent of the children treated with Topivit showed improved resistance against illness.

Power from wood wastes
A biomass cogenerator which converts wood wastes into gas that in turn produces electricity and heat by fuelling an engine has been developed by German researchers.

The gasification system developed by researchers at UMSICHT (Fraunhofer Institute for Environmental, Safety and Energy Technology) in Obserhausen has considerably higher efficiency than those using conventional combustion followed by a steam turbine, reports Fraunhofer Gesselschaft Research News.

In the past, there was no suitable way of generating electricity from solid fuels on a small or medium scale.

Gas-fuelled engines are ideal for driving a generator in combination with recovery of waste heat, even at low power ratings. By means of “fluidized bed gasification”, the researchers found a method of generating a relatively low-tar gas from wood chippings.

The core of the system is the atmospheric circulating fluidized-bed reactor with bed of sand, fed with wood chips. While the particles are held in suspension, the wood turns into gas with the combustible components carbon monoxide, hydrogen and methane.