Enviroment
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The document discusses various topics related to the environment and pollution. It includes questions about litter laws, recycling habits, types of pollution, renewable energy sources, global warming, deforestation, and ways to reduce environmental impact. The reader is prompted to consider their views on issues like banning cars from cities, increasing standards of living versus protecting the environment, and who is most responsible for pollution between individuals and governments.
Enviroment
- 1. Environment & Pollution Are there litter laws where you live? If so, what is the penalty for littering? Do you think cars should be banned from city centers? Do you think people should recycle newspapers? Why or why not? Do you think there are lessons to learn from nature? How has the world changed since you were a child? (technology, values, environment, health) How often is garbage collected in your neighborhood? If humans are really intelligent and not simply manipulated by their genes like any other an imal, why can't they do anything about overpopulation? What are some things that can be recycled? What are some things that your community is doing to help the? What are some things which you recycle? What are some types of pollution? What are some ways that you can reduce pollution in this country? What can you do to help prevent pollution? What can you do to make this world a better place? What do you think of people who smoke cigarettes indoors? Which is more important, increasing people's standard of living, or protecting the environment? Think of a situation in your area involving this issue. Which side would you choose? Who do you think is more responsible for pollution, individual people or the government? Explain. What is the most important issue facing the environment today? Do you know about any anti-pollution programs in your community? What about programs in your native country? Do you usually drink bottled water? Why or Why not? If you could choose one alternative energy source to develop which one would you choose? Why? Are companies more or less environmentally responsible now than they were in the past? Why do you think that is? Do you think recycling is an important community service? Do you recycle? Who should pay for the costs associated with renewable energy? Should we make the development of renewable energy sources an economic priority? What are some ways energy is wasted? What types of energy are popular in your native country? What is the main problem with renewable energy sources? What can large cities do to improve their air quality? How can we protect the environment and at the same time improve people's standard of living? Do you think overpopulation is an important environmental issue? Why or why not? Should an environmental levy be imposed on SUVs not used in the farming community? How would this help the environment? Should gas for motorists be more expensive? What would be the advantages and disadvantages of this? Do think global warming is real? Do you think this is an effect of pollution? Are worried about global warming? If you live on an island or on the coast does this increase the danger from global warming? Why? What's happening to forests in the world? What happens when we remove forests? What can we do to protect forests? Why should we recycle? Does your local government make it easy or hard for citizens to recycle? Are there people in your country who make their living from picking-up other people's garbage? How is pollution effecting the environment of the United States today? How about your own country? Does your country have a smoking ban law in place? What are the benefits/ disadvantages of a smoking ban? How do individual decisions about number of children affect overall population numbers? What is global warming? Do you think nuclear power safe? Who should be allowed it and why? Who should police it? In what ways can we save more water? Please tell your experiences. What should we do to increase the awareness about environmental pollution? Do you have any ideas on how to minimize the use of plastic bags and Styrofoam boxes? Does your local government make it easy or hard for citizens to recycle?
- 2. ECONOMIC IMPORTANCE OF BACTERIA Economic importance of any organism refers to the advantages and disadvantages of that organism to nature, the humans and the environment. Bacteria, a prokaryote and microscopic organism, have the following economic importance: 1. Beneficial effects of Bacteria: Bacteria play important roles in different fields such as agriculture, industry etc. Some of them are mentioned below: A) Role in agriculture a) Scavenging Role: Saprophytic bacteria obtain food from organic remains such as animal excreta, fallen leaves, meat etc. They decompose these substances by action of digestive enzymes aerobically or anaerobically (known as fermentation). Thus they help in sanitation of nature, so also known as scavengers. E.g. Pseudomonas b) Nitrification:Rhizobium bacteria, living in root nodules of leguminous plant symbiotically, helps in fixing atmospheric nitrogen. Similarly, Nitrosomanas and Nitrococcus convert ammonium salt to nitrites. Nitrites are further changed to nitrates by Nitrobacter and Nitrocystis. It enables plants to uptake nitrogen. c) Production of Organic Manure: As stated above, saprophytic bacteria help in breaking of complex organic substance to simpler forms. Thus, in this process, they help to convert farm refuse, dung and other wastes to manure. d) Preparation of Ensilage:Ensilage is preserved cattle fodder prepared by packing fresh chopped fodder sprinkled with molasses. Fermentation activity of bacteria produces lactic acid that acts as preservative in ensilage. e) Production of fuel: Bacteria, while converting animal dung and other organic wastes to manure, help in production of fuel that is a must in gobar gas plant. f) Disposal of sewage: Bacteria help in disposal of sewage by decomposing it and thus, help in environmental sanitation. B) Role in Industry a) Dairy Industry: Bacteria such as Streptococcus lactis convert milk sugar lactose into lactic acid that coagulates casein (milk protein). Then, milk is converted into curd, yoghurt, cheese etc needed for the industry. b) Production of Organic Compounds: Fermentation (breakdown of carbohydrate in absence of oxygen) action of various bacteria produces organic compounds like lactic acid (by Lactobacillus), acetic acid (by Acetobacter aceti), acetone (by Clostridium acetabutylicum) etc. c) Fibre Retting: The action of some bacteria like Clostridium, Pseudomonas etc. help in fibre retting i.e. separation of stem and leaf fibre of plants from other softer tissue. d) Curing: The leaves of tea and tobacco, beans of coffee and coca are cured off their bitterness with the help of action of certain bacteria such as Bacillus megatherium. e) Production of Antibiotics: Number of anti bacterial and anti fungal antibiotics such as Hamycin, Polymyxin, Trichomycin etc are obtained from mycelia bacteria (like Streptomyces). Similarly, Bacillus is used for production of antibiotics such as Bacitracin, Gramicidin etc f) Production of Vitamins: Different kinds of vitamins are produced from bacteria like Riboflavin from Clostridium butylicum, Vitamin B12 from Bacillus megatherium and Vitamin K and B-complex from Escherichia coli. 2. Harmful effects of Bacteria: Though bacteria plays important role in agriculture, industries and natural sanitation etc, it has the following harmful effe cts: a) Food Spoiling: Saprophytic bacteria always not only help in decomposition of dead matters, but they also cause the rotting of vegetables, fruits, meat, bread etc. b) Food Poisoning: Bacteria like Staphylococcus aureus cause food poisoning and cause people diarrhea and vomiting. c) Damaging of domestic articles: Spirochete cytophaga deteriorates cotton, leather and wooden articles. d) Denitrification: Bacteria such as Thiobacillus and Microbacillusconvert nitrate of the soil to the gaseous nitrogen. This hampers plants very much. e) Desulphurication: Bacteria such as Desulfovibrio convert soil sulphates into hydrogen sulphide. f) Cause of Diseases: It is known that over 90% of human diseases and over 10% of plant diseases are caused by bacteria.
- 3. Waste Management What is Waste Recycling? Recycling is processing used materials (waste) into new, useful products. This is done to reduce the use of raw materials that would have been used. Recycling also uses less energy and and great way of controlling air, water and land pollution. Effective recycling starts with household (or the place where the waste was created). In many serious countries, the authorit ies help households with bin bags with labels on them. Households then sort out the waste themselves and place them in the right bags for collection. This makes the work less difficult. Here is how paper waste is recycled: Collection, transportation and storage: The biggest task for paper recycling companies is probably the collection, transporting and sorting of waste paper. This is because we always add paper to other waste items and get them contaminated with food, plastics and metals. Sometimes collected paper is sent back to the landfills because they are too contaminated for use. Try to keep waste paper in separate grades at home or in the office example, do not mix newspapers and corrugated boxes up. All paper recovered is sent to the recycling center, where it is packed, graded, put into bales and sent to the paper mill. At the mill, all the paper is stored in a warehouse until it is needed. Repulping and Screening (say re-pal-pin and skree-nin): From the storage shelves, they are moved into a big paper-grinding machine called a vat (pulper). Here the paper is chopped into tiny pieces, mixed with water and chemicals and heated up to break it down into organic plant material called fibre. After, it is screened to remove contaminants such as bits of plastic and globs of glue. Deinking (say dee-in-kin): This involves washing the pulp with c hemic als to remove printing ink and glue residue. Sometimes, a process called floatation is applied to further remove stubborn stains and stickies. Floatation involves the use of chemicals and air to create bubbles which absorb the stickies in the pulp. Refining, Bleaching and Color Stripping: Refining involves beating the recycled pulp to make them ideal for paper-making. After refining, additional chemicals are added to remove any dyes from the paper. It is then bleached to whiten and brighten it up. Paper making: At this stage, the pulp is ready to be used for paper. Sometimes new pulp (virgin pulp) is added to give it extra strength and smoothness. Water is added to the pulp and sprayed onto a large metal screen in continuous mode. The water is drained on the screen and the fibres begin to bond with each other. As it moves through the paper-making machines, press rollers squeeze out more water, heat them dry and coat them up. They are then finished into rolls.
- 4. Aluminum recycling In recent time, there has been a massive improvement in recycling aluminum cans. In 2003, Americans recycled 62.6 billion aluminum cans. Those cans, placed end-to-end, could make 171 circles around the earth. Every minute, an average of 105,800 aluminum cans are recycled. That is how important can recycling has become. But what is involved here? Here is it... Collection: Local councils provide special can recycling containers (bins) that are clearly marked. This helps people to know what to pla ce in them. Cans include soda, fruit and vegetable cans. Trucks come for these at pick up spots to the recycling centers. Cans may also be metallic or steel, but people do not know the difference. Preparation: At the collection center, a huge magnet is rolled over them as they move on the conveyor belt to pull out all the metal and steel cans. Only the aluminum cans are washed, crushed, condensed in to 30-pounds briquettes for other companies for further processing. The rest is also sorted and sent to their appropriate recycling centers. Melting: The crushed cans are loaded into a burning furnace, where all printing and designs on the cans are removed, melted and blended with new (virgin) aluminum. The molten (liquid) aluminum is poured into moulds and made into bars called ingots. Sheets: The ingots are then fed into powerful rollers, which flatten them into thin sheets of aluminum of about 25.4 in thickness. These thin sheets are rolled into coils and sold or sent to can-making factories. They use the aluminum coils to prepare cans and containers for other food and drink manufacturers. It is estimated that cans collected at collection points take up to 60 days to be appear in the shops again as new cans containing your favourite soda, juice or food. How is glass recycled? Recycling glass starts in your home. There is a reason why many local councils provide different containers for green, brown, plain glass and even glass from broken windows. The reason is that they are all made very differently and mixing them can create huge problems at the recycling center. Collection: Many cities have collection spots. Trucks may also pick them up from your home, or you may be required to drop them off at a point in your town. In all cases, try to do what the authorities have suggested. So, be sure you know the various glass types that are collected from your home. Always wash and separate them into the required grades for collection. Cleaning and Crushing: The glass is transported to the processing plant where contaminants such as metal caps and plastic sleeves are removed. Different grades are treated separately. Clean glass is then crushed into small pieces called cullet. Cullet is in high demand from glass manufacturers. It melts at a lower temperature and it is cheaper than raw glass materials. Ready for use: The cullet is then transported to glass-making factories. Here, it is mixed with sand, soda ash and limestone. It is heated at very high temperature and melted into liquid glass. This liquid is then poured into moulds that give glass its shape. Glass is used for many thingsdepending on what grade they were recycled from. A few items made of recycled glass include fibre-glass, countertops, bottles and jars.