UNIT 1The Environment

Interrelationship Between EVS and Other Subjects

Environment education is the new areas of study of the discipline of education. With recent developments and advances, environmental education is a new source of concern for educators, teachers and students. As with the rapid development in each area, there are problems- both internal and external ones.The environmental education aims at developing in the child and awareness and understanding of the physical and social environment in its totality. Environmental studies involve a childs investigation and systematic exploration of his own natural and social environment and prepare him to solve the problems for improving his life.Environmental education is a process of providing learning experiences to obtain knowledge, understanding, skills and awareness with desirable attitude change about mans relationship with his natural and man-made surroundings which includes the relation of population, pollution, resource allocation, transportation technology and urban and rural planning to the total human environment.

Objectives of environmental education:Goals of EE are to develop a world population that is aware of and concerned about, total environment and its related problems, and commitment to work individually and collectively towards solution of current problems and the prevention of new ones.A few objectives are given below:1. Awareness i.e. acquire an awareness of sensitivity to the total environment and its allied problems.2. Knowledge i.e. gain a variety of experiences and acquire a basic understanding of the environment and its associated problems.3. Attitude i.e acquire a set of values and feelings of concern for the environment and the motivation for active participation in the environmental improvement and protection.4. Skill i.e. acquire skills for identifying and solving environmental problems.5. Evaluation ability i.e. evaluate environmental measures and education programmes in terms of ecological, economic and social, aesthetic and educational factors.6. Participation i.e. provide an opportunity to be actively involved at all levels in working towards the resolution of environmental problems.

EcosystemThe term ecosystem was proposed by A.C. Tansley in 1935 where eco implies the environment and system denotes an interacting, interdependent complex. Ecosystem may be defined as the system resulting from the integration of all living and non-living factors of the environment. Thus, any unit that includes all the organisms i.e. the communities in a given area interact with the physical environment so that a flow of energy leads to clearly defined trophic structure, biotic diversity and material cycle within the system is known as ecological system or ecosystem.

Basic Components of Ecosystem The structure of an ecosystem is basically a description of the species of organisms that are present, including information on their life histories, populations and distribution in space. It is a guide to whos who in the ecosystem. It also includes descriptive information on the non-living (physical) features of environment, including the amount and distribution of nutrients.The structure of ecosystem provides information about the range of climatic conditions that prevail in the area. From structural point of view all ecosystems consist of following four basic components:1. Abiotic Substances:These include basic inorganic and organic compounds of the environment or habitat of the organism. The inorganic components of an ecosystem are carbon dioxide, water, nitrogen, calcium, phosphate, all of which are involved in matter cycles (biogeochemical cycles).The organic components of an ecosystem are proteins, carbohydrates, lipids and amino acids, all of which are synthesized by the biota (flora and fauna) of an ecosystem and are reached to ecosystem as their wastes, dead remains, etc, The climate, temperature, light, soil, etc., are other abiotic components of the ecosystem.2. Producers:Producers are autotrophic organisms like chemosynthetic and photosynthetic bacteria, blue green algae, algae and all other green plants. They are called ecosystem producers because they capture energy from non-organic sources, especially light, and store some of the energy the form of chemical bonds, for the later use.Algae of various types are the most important producers of aquatic ecosystems, although in estuaries and marshes, grasses may be important as producers. Terrestrial ecosystems have trees, shrubs, herbs, grasses, and mosses that contribute with varying importance to the production of the ecosystem.Since heterotrophic organisms depend on plants and other autotrophic Organisms like bacteria and algae for their nutrition, the amount of energy that the producers capture, sets the limit on the availability of energy for the ecosystem. Thus, when a green plant captures a certain amount of energy from sunlight, it is said to produce the energy for the ecosystem.3. Consumers:They are heterotrophic organisms in the ecosystem which eat other living creatures. There are herbivores, which eat plants, and carnivores, which eat other animals. They are also called phagotrophs or macroconsumers. Sometimes herbivores are called primary macroconsumers and carnivores are called secondary Macroconsumers.4. Reducers or Decomposers:Reducers, decomposers, saprotrophs or Macroconsumers are heterotrophic organisms that breakdown dead and waste matter. Fungi and certain bacteria are the prime representatives of this category. Enzymes are secreted by their cells into or onto dead plant and animal debris. These chemicals digest the dead organism into smaller bits or molecules, which can be absorbed by the fungi or bacteria (saprotrophs).The decomposers take the energy and matter that they harvest during this feeding process for their own metabolism. Heat is liberated in each chemical conversion along the metabolic pathway.No ecosystem could function long without decomposers. Dead organisms would pile up without rotting, as would waste products. It would not be long before an essential element, phosphorus, for example, would be first in short supply and then gone altogether, because the dead corpses littering the landscape would be hoarding the entire supply.Thus, the importance of the decomposers to the ecosystem is that they tear apart organisms and in their metabolic processes release to the environment atoms and molecules that can be reused again by autotrophic organisms. They are not important to the ecosystem from the energy point of view but from the material (nutrient) point of view. Energy cannot be recycled, but matter can be.Food Chain and Food WebEvery organism needs to obtain energy in order to live. For example, plants get energy from the sun, some animals eat plants, and some animals eat other animals. A food chain is the sequence of who eats whom in a biological community (an ecosystem) to obtain nutrition. A food chain starts with the primary energy source, usually the sun or boiling-hot deep sea vents. The next link in the chain is an organism that make its own food from the primary energy source -- an example is photosynthetic plants that make their own food from sunlight (using a process called photosynthesis) and chemosynthetic bacteria that make their food energy from chemicals in hydrothermal vents. These are called autotrophs or primary producers. Next come organisms that eat the autotrophs; these organisms are called herbivores or primary consumers -- an example is a rabbit that eats grass. The next link in the chain is animals that eat herbivores - these are called secondary consumers -- an example is a snake that eat rabbits. In turn, these animals are eaten by larger predators -- an example is an owl that eats snakes. The tertiary consumers are are eaten by quaternary consumers -- an example is a hawk that eats owls. Each food chain end with a top predator, and animal with no natural enemies (like an alligator, hawk, or polar bear). The arrows in a food chain show the flow of energy, from the sun or hydrothermal vent to a top predator. As the energy flows from organism to organism, energy is lost at each step. A network of many food chains is called a food web. Trophic Levels:The trophic level of an organism is the position it holds in a food chain. 1. Primary producers (organisms that make their own food from sunlight and/or chemical energy from deep sea vents) are the base of every food chain - these organisms are called autotrophs. 2. Primary consumers are animals that eat primary producers; they are also called herbivores (plant-eaters). 3. Secondary consumers eat primary consumers. They are carnivores (meat-eaters) and omnivores (animals that eat both animals and plants). 4. Tertiary consumers eat secondary consumers. 5. Quaternary consumers eat tertiary consumers. 6. Food chains "end" with top predators, animals that have little or no natural enemies. When any organism dies, it is eventually eaten by detrivores (like vultures, worms and crabs) and broken down by decomposers (mostly bacteria and fungi), and the exchange of energy continues. Some organisms' position in the food chain can vary as their diet differs. For example, when a bear eats berries, the bear is functioning as a primary consumer. When a bear eats a plant-eating rodent, the bear is functioning as a secondary consumer. When the bear eats salmon, the bear is functioning as a tertiary consumer (this is because salmon is a secondary consumer, since salmon eat herring that eat zooplankton that eat phytoplankton, that make their own energy from sunlight). Think about how people's place in the food chain varies - often within a single meal. Numbers of Organisms:In any food web, energy is lost each time one organism eats another. Because of this, there have to be many more plants than there are plant-eaters. There are more autotrophs than heterotrophs, and more plant-eaters than meat-eaters. Although there is intense competition between animals, there is also an interdependence. When one species goes extinct, it can affect an entire chain of other species and have unpredictable consequences. EquilibriumAs the number of carnivores in a community increases, they eat more and more of the herbivores, decreasing the herbivore population. It then becomes harder and harder for the carnivores to find herbivores to eat, and the population of carnivores decreases. In this way, the carnivores and herbivores stay in a relatively stable equilibrium, each limiting the other's population. A similar equilibrium exists between plants and plant-eaters. Forest: A forest is a large area of land covered with trees or other woody vegetation.[1] Hundreds of more precise definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing and ecological function.[2][3][4] According to the widely-used[5][6] United Nations Food and Agriculture Organization definition, forests covered an area of four billion hectares (15 million square miles) or approximately 30 percent of the world's land area in 2006.[4]Forests are the dominant terrestrial ecosystem on Earth, and are distributed across the globe.[7] Forests account for 75% of the gross primary productivity of the Earth's biosphere, and contain 80% of the Earth's plant biomass.[7]Forests at different latitudes form distinctly different ecozones: boreal forests near the poles tend to consist of evergreens, while tropical forests near the equator tend to be distinct from the temperate forests at mid-latitude. The amount of precipitation and the elevation of the forest also affects forest composition.Human society and forests influence each other in both positive and negative ways.[8] Forests provide ecosystem services to humans and serve as tourist attractions. Forests can also impose costs, affect people's health, and interfere with tourist enjoyment. Human activities, including harvesting forest resources, can negatively affect forest ecosystems.Grasslands: Grasslands are areas where the vegetation is dominated by grasses (Poaceae), however sedge (Cyperaceae) and rush (Juncaceae) families can also be found. Grasslands occur naturally on all continents except Antarctica. Grasslands are found in most ecoregions of the Earth. For example there are five terrestrial ecoregion classifications (subdivisions) of the temperate grasslands, savannas, and shrublands biome ('ecosystem'), which is one of eight terrestrial ecozones of the Earth's surface.Water: Water plays an array of vital roles in ecosystems across the planet. Although many other substances are necessary for life and for ecosystems to exist, without water nothing else would function to produce life as we know it.Life Support Water is essential to life since every living cell of every living thing needs water for sustenance. Without water an ecosystem would not exist.Erosion Water is an agent of erosion. Rainwater, river water and freezing and thawing water can break up enormous amounts of rock into small fragments, forming some of the building materials of soil.Climatic Effects Water in the atmosphere affects the climate, as in cloud formations that can produce snow and rain. Clouds can also reflect sunlight away from Earth, producing a cooling effect.Evaporative Cooling The cooling effect of water can also result from evaporation or evapotranspiration (the combination of evaporation in general and the evaporation of water through plants' leaves called transpiration).Hydropower Human industry has produced hydropower, power from water through dams where turbines generate electricity. This usage has an impact on ecosystems, especially migratory fish.Agro Ecosystems: An agroecosystem is the basic unit of study in agroecology, and is somewhat arbitrarily defined as a spatially and functionally coherent unit of agricultural activity, and includes the living and nonliving components involved in that unit as well as their interactions. [1]An agroecosystem can be viewed as a subset of a conventional ecosystem. As the name implies, at the core of an agroecosystem lies the human activity of agriculture. However, an agroecosystem is not restricted to the immediate site of agricultural activity (e.g. the farm), but rather includes the region that is impacted by this activity, usually by changes to the complexity of species assemblages and energy flows, as well as to the net nutrient balance. Traditionally an agroecosystem, particularly one managed intensively, is characterized as having a simpler species composition and simpler energy and nutrient flows than "natural" ecosystem.[2] Likewise, agroecosystems are often associated with elevated nutrient input, much of which exits the farm leading to eutrophication of connected ecosystems not directly engaged in agriculture.[3]

UNIT 2Natural ResourcesNatural resources occur naturally within environments that exist relatively undisturbed by humanity, in a natural form. Anatural resource is often characterized by amounts of biodiversity and geodiversity existent in various ecosystems.Natural resources are derived from the environment. Some of them are essential for our survival while most are used for satisfying our needs. Natural resources may be further classified in different ways.Natural resources are materials and components (something that can be used) that can be found within the environment. Every man-made product is composed of natural resources (at its fundamental level). A natural resource may exist as a separate entity such as fresh water, and air, as well as a living organism such as a fish, or it may exist in an alternate form which must be processed to obtain the resource such as metal ores, oil, and most forms of energy.Uses and Misuse of Natural Resources:Use/ Conservation of natural resources: CONSERVATION OF NATURAL RESOURCES As the human population is continuously growing the consumption of natural resources is also increasing. With the increasing industrialization and urbanization of the modern human society, the use of all the resources is rising. If they are not properly used and well managed, a serious scarcity will result. Therefore we need to conserve the natural resources. This will also upset the ecological balance. Conservation is the proper management of a natural resource to prevent its exploitation, destruction or degradation. Conservation is the sum total of activities, which can derive benefits from natural resources but at the same time prevent excessive use leading to destruction or degradation. 6. Need for Conservation of Natural Resources We know that nature provides us all our basic needs but we tend to overexploit it. If we go on exploiting the nature, there will be no more resources available in future. There is an urgent need to conserve the nature. Some of the needs are : to maintain ecological balance for supporting life. to preserve different kinds of species (biodiversity). to make the resources available for present and future generation. to ensure the survival of human race. 7. Conservation of Natural Resources and Traditions of India The need for conservation of natural resources was felt by our predecessors and in India, there was a tradition of respecting and preserving the nature and natural resources. Natural resources were conserved in the form of sacred groves/forests, sacred pools and lakes, sacred species etc. In our country the conservation of natural forests is known from the time of Lord Asoka. Sacred forests are forest patches of different dimensions dedicated by the tribal to their deities and ancestral spirits. Cutting down trees, hunting and other human interferences were strictly prohibited in these forests. This practice is wide spread particularly in peninsular, central and eastern India and has resulted in the protection of a large number of plants and animals and. Similarly, several water bodies, e.g., Khecheopalri lake in Sikkim was declared sacred by people, thus, protecting aquatic flora and fauna. Worshipping certain plants like banyan, peepal, tulsi etc. has not only preserved them but also encouraged us for their plantation. History recalls numerous instances where people have laid down their lives in protecting the trees. Recent Chipko movement in India is one of the best examples. This movement was started by the women in Gopeshwar village in Garhwal in the Himalayas. They stopped the felling of trees by hugging them when the lumbermen arrived to cut them. This saved about 12000 square kilometers of the sensitive water catchment area. Similar movements also occurred in some other parts of the country. 8. Conservation of Soil In the previous section we learnt about the various causes of soil erosion. Soil loses its fertility due to erosion. So we need to conserve the soil. Soil conservation means checking soil erosion and improving soil fertility by adopting various methods. Let us know some of these methods. 1. Maintenance of soil fertility: The fertility can be maintained by adding manure and fertilizers regularly as well as by rotation of crop. 2. Control on grazing: Grazing should be allowed only on the areas meant for it and not on agricultural land. 3. Reforestation: Planting of trees and vegetation reduces soil erosion by both water and wind. 4. Terracing: Dividing a slope into several flat fields to control rapid run of water. It is practiced mostly in hilly areas. 5. Contour ploughing: Ploughing at right angles to the slope allows the furrows to trap water and check soil erosion by rain water. 9. Conservation of Water Conservation and management of water are essential for the survival of mankind, plants and animals. This can be achieved adopting the following methods: 1. Growing vegetation in the catchment areas, which will hold water in the soil and allow it to percolate into deeper layers and contribute to formation of ground water. 2. Constructing dams and reservoirs to regulate supply of water to the fields, as well as to enable generating hydroelectricity. 3. Sewage should be treated and only the clear water should be released into the rivers. 4. Industrial wastes (effluents) should be treated to prevent chemical and thermal pollution of fresh water. 5. Judicious use of water in our day-to-day life. 6. Rainwater harvesting should be done by storing rainwater and recharging groundwater. 10. Different methods of water harvesting 11. Conservation of Biodiversity Now you have an idea of the importance of biodiversity for our survival and how it is destroyed. Let us know how to protect the biodiversity. There are two basic strategies for conservation of biodiversity: (i) In-situ conservation (ii) Ex-situ conservation (i) In-situ (on site) conservation includes the protection of plants and animals within their natural habitats or in protected areas. Protected areas are areas of land or sea dedicated to protection and maintenance of biodiversity. For example: e.g., National Parks, Wildlife Sanctuaries, Biosphere Reserves, etc. (ii) Ex-situ (off site) conservation is the conservation of plants and animals outside their natural habitats. These include Botanical Gardens, Zoo, Gene Banks, DNA Banks, Seed Banks, Pollen Banks, Seedling and Tissue Culture etc. 12. Conservation of Forests Forests is an important part of the environment, because trees clean the air and keep the atmosphere cool. We cannot live without plants, because the oxygen need for breathing is produced by plants. Trees absorb sunlight and reduce the heat. Plants provide fodder for animals, firewood, timber, medicines, honey, wax, gum, lac and food for us. Tree roots penetrate deep into the soil and from cavities in the ground. The dry leaves which fall on ground, cover the soil and absorb more rain water, which slowly percolates through the soil. Thus, a large portion of the rain water can be retained in the field, by planting more trees. Different Types of Misuse of Natural Resources

Natural ResourceTypes of misuse/ecological problems

I Ecological ResourcesExcessive mining

Loss of forest area (if mines are in forest)

Displacement of population and their profession

Loss of agricultural lands (if resource is in cultivated land)

Dumping of ore or spent ore on surface leading to soil / water pollution

Risks and health hazards to employees / population

Directly contributing pollution to water / soil /air in petroleum exploration and processing industry

II Hydro ecological Resources Excessive, unscientific and uneconomic ground water exploitation

Exploration of underground water without any regard to its rate of rechange

Displacement of human settlement during establishment of hydro-projects

Loss of agricultural / forest area in standing water (in dam construction)

Unscientific use / overuse of irrigation water leading to loss of fertility, increased pollution of land / water

Loss of biodiversity

III Atmospheric Resources Destructive use of atmospheric oxygen to burn carbon sources to produce CO and CO2 which in turn change the composition of air

Deforestation on one side and polluting the atmosphere by CO2 loading on other side have led to increased CO2 levels in atmosphere

Ozone coverage is slowly degenerating due to release of chlorine generating gases to atmosphere

V Forest resources

Continuous deforestation for commercial and fuel purposes

Encroachment of forest area for agriculture,mining, industrial purposes

Loss of forest area for irrigation dams

Loss of biodiversity due to encouragement /discouragement of specific species of plants

VI Crop resources Unnatural crosses between species

Transgenic breeding leading to modification of original characters of plants to destroy natural plant types interfering in natural regeneration process

Tissue culture aided cloning

VII Aquatic resources Excessive fishing around the coast

Loss of biodiversity in aquatic population

Premature fishing for commercial purpose

Destruction of herbivorous fishes by carnivorous fishes

VIII Animal resources Interference in natural breeding by in-vitro fertilization and artificial insemination technique

Severe damage to community living in animals due to forced solitary rearing

Hormonal regulation of physiology of animals

Cloning of animals

IX Wildlife resources Keeping the animals in captivity to derive entertainment value from them

Killing the wild animals for pleasure (hunting) or for trading or for food

Ignoring the ecobalance and biodiversity and failure to preserve them

X Human resources Discriminating the human beings on sex

Abuse of children as cheap source of labour

Bonded labours

Recycling of materialsRecycling is a process to change waste materials into new products to prevent waste of potentially useful materials, reduce the consumption of fresh raw materials, reduce energy usage, reduce air pollution (from incineration) and water pollution (from landfilling) by reducing the need for "conventional" waste disposal, and lower greenhouse gas emissions as compared to plastic production.[1][2] Recycling is a key component of modern waste reduction and is the third component of the "Reduce, Reuse and Recycle" waste hierarchy.There are some ISO standards related to recycling such as ISO 15270:2008 for plastics waste and ISO 14001:2004 for environmental management control of recycling practice.Recyclable materials include many kinds of glass, paper, metal, plastic, textiles, and electronics. The composting or other reuse of biodegradable wastesuch as food or garden wasteis also considered recycling.[2] Materials to be recycled are either brought to a collection center or picked up from the curbside, then sorted, cleaned, and reprocessed into new materials bound for manufacturing.In the strictest sense, recycling of a material would produce a fresh supply of the same materialfor example, used office paper would be converted into new office paper, or used foamed polystyrene into new polystyrene. However, this is often difficult or too expensive (compared with producing the same product from raw materials or other sources), so "recycling" of many products or materials involves their reuse in producing different materials (e.g., paperboard) instead. Another form of recycling is the salvage of certain materials from complex products, either due to their intrinsic value (e.g., lead from car batteries, or gold from computer components), or due to their hazardous nature (e.g., removal and reuse of mercury from various items). Critics dispute the net economic and environmental benefits of recycling over its costs, and suggest that proponents of recycling often make matters worse and suffer from confirmation bias. Specifically, critics argue that the costs and energy used in collection and transportation detract from (and outweigh) the costs and energy saved in the production process; also that the jobs produced by the recycling industry can be a poor trade for the jobs lost in logging, mining, and other industries associated with virgin production; and that materials such as paper pulp can only be recycled a few times before material degradation prevents further recycling.[3] Proponents of recycling dispute each of these claims, and the validity of arguments from both sides has led to enduring controversy.

In the past, human interaction with nature, although often having a disruptive effect on nature, often also enriched the quality and variety of the living world and its habitats - e.g. through the creation of artificial landscapes and soil cultivation by local farmers. Today, however, human pressure on natural environments is greater than before in terms of magnitude and efficiency in disrupting nature and natural landscapes, most notably: intensive agriculture replacing traditional farming; this combined with the subsidies of industrial farming has had an enormous effect on western rural landscapes and continues to be a threat. mass tourism affecting mountains and coasts. the policies pursued in the industry, transport and energy sectors having a direct and damaging impact on the coasts, major rivers (dam construction and associated canal building) and mountain landscapes (main road networks). the strong focus of forestry management on economic targets primarily causes the decline in biodiversity, soil erosion and other related effects.The clearest manifestations of the degradation of the natural environment are: Reduction and fragmentation of habitats and landscapes

The expansion of humans activities into the natural environment, manifested by urbanisation, recreation, industrialisation, and agriculture, results in increasing uniformity in landscapes and consequential reduction, disappearance, fragmentation or isolation of habitats and landscapes. It is evident that the increasing exploitation of land for human use greatly reduces the area of each wildlife habitat as well as the total area surface throughout Europe. The consequences are: A decreased species diversity, due to reduced habitable surface area which corresponds to a reduced "species carrying capacity". The reduction of the size of habitats also reduces the genetic diversity of the species living there. Smaller habitats can only accommodate smaller populations, this results in an impoverished gene pool. The reduction of genetic resources of a species diminishes its flexibility and evolutionary adaptability to changing situations. This has significant negative impacts on its survival.The conditions under which the reduction of habitats often occur prevent living organisms making use of their normal ways to flee their threatened habitat. Those escape routes include migration to other habitats, adaption to the changing environment, or genetic interchange with populations in nearby habitats. Of particular concern is: The abrupt nature of human intervention; human projects are planned and implemented on a much shorter time scale than natural processes; Furthermore human intervention, such as the construction of buildings, motorways or railways results in the fragmentation of habitats, which strongly limits the possibility for contact or migration among them; In extreme cases even the smallest, narrowest connections between habitats are broken off. Such isolation is catastrophic for life in the habitat fragments. Loss of Species of Fauna and Flora

Although relatively few species of Europe's fauna and flora have actually become totally extinct during this century, the continent's biodiversity is affected by decreasing species numbers and the loss of habitats in many regions. Approximately 30 % of the vertebrates and 20 % of the higher plants are classified as "threatened". Threats are directly linked to the loss of habitats due to destruction, modification and fragmentation of ecosystems as well as from overuse of pesticides and herbicides, intensive farming methods, hunting and general human disturbance. The overall deterioration of Europe's air and water quality add to the detrimental influence.

Agriculture Europe's natural environment is inextricably linked with agriculture and forestry. Since agriculture traditionally depends on sound environmental conditions, farmers have a special interest in the maintenance of natural resources and for centuries maintained a mosaic of landscapes which protected and enriched the natural environment. As a result of needs for food production since the 1940s, policies have encouraged increased pro- duction through a variety of mechanisms, including price support, other subsidies and support for research and development. The success achieved in agricultural production has however entailed increased impact on the environment. Modern agriculture is responsible for the loss of much wildlife and their habitats in Europe, through reduction and fragmentation of habitats and wildlife populations. The drainage of wetlands, the destruction of hedgerows and the intensive use of fertilizers and pesticides can all pose a threat to wildlife. Highly specialised monoculture are causing significant loss in species abundance and diversity. On the other hand increased production per hectare in intensive areas, raising of livestock volume, and lower prices for agricultural products also caused marginalization of agricultural land, changing the diversity of European landscapes into the direction of two main types: Intensive Agriculture and Abandoned land.

Energy Abandonment can be positive for nature, but this is not necessarily so. Land abandonment increases the risk of fire in the Mediterranean Region, causes a decline of small-scale landscape diversity and can also cause decrease in species diversity. All energy types have potential impacts on the natural environment to varying degrees at all stages of use, from extraction through processing to end use. Generating energy from any source involves making the choices between impacts and how far those impacts can be tolerated at the local and global scale. This is especially of importance for nuclear power, where there are significant risks of radioactive pollution such as at Chernobyl. Shell Oil Company and IUCN have jointly drafted environmental regulations for oil-exploitation in Arctic areas of Siberia. Other oil companies are aware of this and use these environmental regula- tions voluntarily for developing oil fields. Into the future the sustainability of the natural environment will be improved as trends away from damaging energy uses and extractive methods reduce and whilst real cost market forces and the polluter pays principle take effect.

Fisheries The principle of the fisheries sector is towards sustainable catches of wild aquatic fauna. The principle environmental impact associated with fisheries activities is the unsustainable har- vesting of fish stocks and shellfish and has consequences for the ecological balance of the aquatic environment. The sector is in a state of "crisis", with over capacity of the fleet, overexploitation of stocks, debt, and marketing problems. Growing aquaculture industry may increase water pollution in western Europe, and is appearing to be a rising trend in the Mediterranean and Central/East Europe. Fishing activities have an impact on cetaceans and there is concern that large numbers of dolphins, and even the globally endangered Monk seal, are being killed.

Forestry Compared to other landuses, forest management has the longest tradition in following sustainable principles due to which over 30% of Europe is still covered with trees. Without such an organised approach, forests are likely to have already disappeared from Europe's lowlands. However, as an economic sector, forestry has also impacted severely on the naturalness of Europe's forests: soils have been drained, pesticides and fertilizers applied, and exotic species planted. In many areas monocultures have replaced the original diverse forest composition. Monocultures are extremely sensitive to insect infestations, fires or wind, and so can lead to financial losses as well as biological decline. The inadequate afforestation practices characterize new trends in impacting on the sustainability of the natural environment.

Industry Almost all forms of industry have an impact on the natural environment and its sustainability. The impact varies at different stages in the life cycle of a product, depending upon the raw materials used through to the final end use of the product for waste residue, re-use or recycling. Industrial accidents and war damage to industrial plants can also endanger the natural environment.

Tourism and Recreation Tourism and recreation impact in various ways on the natural environment. On the one hand, natural areas form the very basis of many touristic attractions by highlighting scenic value or exceptional encounters with fauna and flora. However, some forms of tourism can be extremely detrimental to ecologically sensitive areas, resulting in habitat degeneration or destruction, in the disturbance or hunting even rare or threatened species. The pressure from short holiday seasons and specific, sometimes small, locations of touristic interest result in conflicting land-uses, such as in the Alpine regions, at Mediterranean beaches and along many banks of inland waters.

Transport and Infrastructure Transport is perhaps the major contributor to pollution in the world today, particularly global envi- ronmental issues such as the greenhouse effect. The key impacts of transportation include frag- mentation of habitats and species and genetic populations, disruption of migration and traffic mortalities to wildlife. Since the 1970s transport has become a major consumer of non-renewable resources, 80% of oil consumption coming from road transport.

UNIT 3Pollution

Air Pollution: Pollution is now a common place term, that our ears are attuned to. We hear about the various forms of pollution and read about it through the mass media. Air pollution is one such form that refers to the contamination of the air, irrespective of indoors or outside. A physical, biological or chemical alteration to the air in the atmosphere can be termed as pollution. It occurs when any harmful gases, dust, smoke enters into the atmosphere and makes it difficult for plants, animals and humans to survive as the air becomes dirty.Air pollution can further be classified into two sections- Visible air pollution and invisible air pollution. Another way of looking at Air pollution could be any substance that holds the potential to hinder the atmosphere or the well being of the living beings surviving in it. The sustainment of all things living is due to a combination of gases that collectively form the atmosphere; the imbalance caused by the increase or decrease of the percentage of these gases can be harmful for survival.Causes of Air pollution, several divisions can be made. Primarily air pollutants can be caused by primary sources or secondary sources. The pollutants that are a direct result of the process can be called primary pollutants. A classic example of a primary pollutant would be the sulfur-dioxide emitted from factoriesSecondary pollutants are the ones that are caused by the inter mingling and reactions of primary pollutants. Smog created by the interactions of several primary pollutants is known to be as secondary pollutant.Causes of Air pollution1. Burning of Fossil Fuels: Sulfur dioxide emitted from the combustion of fossil fuels like coal, petroleum and other factory combustibles is one the major cause of air pollution. Pollution emitting from vehicles including trucks, jeeps, cars, trains, airplanes cause immense amount of pollution. We rely on them to fulfill our daily basic needs of transportation. But, there overuse is killing our environment as dangerous gases are polluting the environment. Carbon Monooxide caused by improper or incomplete combustion and generally emitted from vehicles is another major pollutant along with Nitrogen Oxides, that is produced from both natural and man made processes.2. Agricultural activities: Ammonia is a very common by product from agriculture related activities and is one of the most hazardous gases in the atmosphere. Use of insecticides, pesticides and fertilizers in agricultural activities has grown quite a lot. They emit harmful chemicals into the air and can also cause water pollution.3. Exhaust from factories and industries: Manufacturing industries release large amount of carbon monoxide, hydrocarbons, organic compounds, and chemicals into the air thereby depleting the quality of air. Manufacturing industries can be found at every corner of the earth and there is no area that has not been affected by it. Petroleum refineries also release hydrocarbons and various other chemicals that pollute the air and also cause land pollution.4. Mining operations: Mining is a process wherein minerals below the earth are extracted using large equipments. During the process dust and chemicals are released in the air causing massive air pollution. This is one of the reason which is responsible for the deteriorating health conditions of workers and nearby residents.5. Indoor air pollution: Household cleaning products, painting supplies emit toxic chemicals in the air and cause air pollution. Have you ever noticed that once you paint walls of your house, it creates some sort of smell which makes it literally impossible for you to breathe.Effects of Air pollution1. Respiratory and heart problems: The effects of Air pollution are alarming. They are known to create several respiratory and heart conditions along with Cancer, among other threats to the body. Several millions are known to have died due to direct or indirect effects of Air pollution. Children in areas exposed to air pollutants are said to commonly suffer from pneumonia and asthma.2. Global warming: Another direct effect is the immediate alterations that the world is witnessing due to Global warming. With increased temperatures world wide, increase in sea levels and melting of ice from colder regions and icebergs, displacement and loss of habitat have already signaled an impending disaster if actions for preservation and normalization arent undertaken soon.3. Acid Rain: Harmful gases like nitrogen oxides and sulfur oxides are released into the atmosphere during the burning of fossil fuels. When it rains, the water droplets combines with these air pollutants, becomes acidic and then falls on the ground in the form of acid rain. Acid rain can cause great damage to human, animals and crops.4. Eutrophication: Eutrophication is a condition where high amount of nitrogen present in some pollutants gets developed on seas surface and turns itself into algae and and adversely affect fish, plants and animal species. The green colored algae that is present on lakes and ponds is due to presence of this chemical only.5. Effect on Wildlife: Just like humans, animals also face some devastating affects of air pollution. Toxic chemicals present in the air can force wildlife species to move to new place and change their habitat. The toxic pollutants deposit over the surface of the water and can also affect sea animals.6. Depletion of Ozone layer: Ozone exists in earths stratosphere and is responsible for protecting humans from harmful ultraviolet (UV) rays. Earths ozone layer is depleting due to the presence of chlorofluorocarbons, hydro chlorofluorocarbons in the atmosphere. As ozone layer will go thin, it will emit harmful rays back on earth and can cause skin and eye related problems. UV rays also have the capability to affect crops.When you try to study the sources of Air pollution, you enlist a series of activities and interactions that create these pollutants. There are two types of sources that we will take a look at: Natural sources and Man-made sources.Natural sources of pollution include dust carried by the wind from locations with very little or no green cover, gases released from the body processes of living beings (Carbon dioxide from humans during respiration, Methane from cattle during digestion, Oxygen from plants during Photosynthesis). Smoke from the combustion of various inflammable objects, volcanic eruptions etc along with the emission of polluted gases also make it to the list of Natural sources of Pollution.While looking at the man-made contributions towards air pollution, smoke again features as a prominent component. The smoke emitted from various forms of combustion like in bio mass, factories, vehicles, furnaces etc. Waste used to create landfills generate methane, that is harmful in several ways. The reactions of certain gases and chemicals also form harmful fumes that can be dangerous to the well being of living creatures.Solutions for Air Pollution1. Use public mode of transportation: Encourage people to use more and more public modes of transportation to reduce pollution. Also, try to make use of car pooling. If you and your colleagues come from the same locality and have same timings you can explore this option to save energy and money.2. Conserve energy: Switch off fans and lights when you are going out. Large amount of fossil fuels are burnt to produce electricity. You can save the environment from degradation by reducing the amount of fossil fuels to be burned.3. Understand the concept of Reduce, Reuse and Recycle: Do not throw away items that are of no use to you. In-fact reuse them for some other purpose. For e.g. you can use old jars to store cereals or pulses.4. Emphasis on clean energy resources: Clean energy technologies like solar, wind and geothermal are on high these days. Governments of various countries have been providing grants to consumers who are interested in installing solar panels for their home. This will go a long way to curb air pollution.5. Use energy efficient devices: CFL lights consume less electricity as against their counterparts. They live longer, consume less electricity, lower electricity bills and also help you to reduce pollution by consuming less energy.Several attempts are being made world wide on a personal, industrial and governmental levels to curb the intensity at which Air Pollution is rising and regain a balance as far as the proportions of the foundation gases are concerned. This is a direct attempt at slacking Global warming. We are seeing a series of innovations and experiments aimed at alternate and unconventional options to reduce pollutants. Air Pollution is one of the larger mirrors of mans follies, and a challenge we need to overcome to see a tomorrow.Improving indoor Air QualityIndoor air quality (IAQ) is a term which refers to the air quality within and around buildings and structures, especially as it relates to the health and comfort of building occupants. IAQ can be affected by gases (including carbon monoxide, radon, volatile organic compounds), particulates, microbial contaminants (mold, bacteria), or any mass or energy stressor that can induce adverse health conditions. Source control, filtration and the use of ventilation to dilute contaminants are the primary methods for improving indoor air quality in most buildings. Residential units can further improve indoor air quality by routine cleaning of carpets and area rugs. EPA has guidelines for frequency of cleaning based on traffic, number of household members, pets, children and smokers. Carpets and rugs act like an air filter and must be cleaned.Determination of IAQ involves the collection of air samples, monitoring human exposure to pollutants, collection of samples on building surfaces, and computer modelling of air flow inside buildings.IAQ is part of indoor environmental quality (IEQ), which includes IAQ as well as other physical and psychological aspects of life indoors (e.g., lighting, visual quality, acoustics, and thermal comfort).Indoor air pollution in developing nations is by far the most deadly risk globally. A major source of indoor air pollution in developing countries is the burning of biomass (e.g. wood, charcoal, dung, or crop residue) for heating and cooking.The resulting exposure to high levels of particulate matter resulted in between 1.5 million and 2 million deaths in 2000.

There are three basic strategies to improve indoor air quality1. Source Control2. Improved Ventilation, and3. Air cleanersSource ControlUsually the most effective way to improve indoor air quality is to eliminate individual sources of pollution or to reduce their emissions. Some sources, like those that contain asbestos, can be sealed or enclosed; others, like gas stoves, can be adjusted to decrease the amount of emissions. In many cases, source control is also a more cost-efficient approach to protecting indoor air quality than increasing ventilation because increasing ventilation can increase energy costs.

Ventilation ImprovementsFor most indoor air quality problems in the home, source control is the most effective solution.Another approach to lowering the concentrations of indoor air pollutants in your home is to increase the amount of outdoor air coming indoors. Most home heating and cooling systems, including forced air heating systems, do not mechanically bring fresh air into the house. Opening windows and doors, operating window or attic fans, when the weather permits, or running a window air conditioner with the vent control open increases the outdoor ventilation rate. Local bathroom or kitchen fans that exhaust outdoors remove contaminants directly from the room where the fan is located and also increase the outdoor air ventilation rate.It is particularly important to take as many of these steps as possible while you are involved in short-term activities that can generate high levels of pollutants for example, painting, paint stripping, heating with kerosene heaters, cooking, or engaging in maintenance and hobby activities such as welding, soldering, or sanding. You might also choose to do some of these activities outdoors, if you can and if weather permits.Air CleanersThere are many types and sizes of air cleaners on the market, ranging from relatively inexpensive table-top models to sophisticated and expensive whole-house systems. Some air cleaners are highly effective at particle removal, while others, including most table-top models, are much less so. Air cleaners are generally not designed to remove gaseous pollutants.The effectiveness of an air cleaner depends on how well it collects pollutants from indoor air (expressed as a percentage efficiency rate) and how much air it draws through the cleaning or filtering element (expressed in cubic feet per minute). A very efficient collector with a low air-circulation rate will not be effective, nor will a cleaner with a high air-circulation rate but a less efficient collector. The long-term performance of any air cleaner depends on maintaining it according to the manufacturer's directions.Another important factor in determining the effectiveness of an air cleaner is the strength of the pollutant source. Table-top air cleaners, in particular, may not remove satisfactory amounts of pollutants from strong nearby sources. People with a sensitivity to particular sources may find that air cleaners are helpful only in conjunction with concerted efforts to remove the source.Over the past few years, there has been some publicity suggesting that houseplants have been shown to reduce levels of some chemicals in laboratory experiments. There is currently no evidence, however, that a reasonable number of houseplants remove significant quantities of pollutants in homes and offices. Indoor houseplants should not be over-watered because overly damp soil may promote the growth of microorganisms which can affect allergic individuals.

Water and the environmentWater is crucial for all life on earth. It plays an essential role in our health, economy, food production, and environment. Safe drinking water and freshwater are imperative for development and public health since 21 of the 37 primary diseases in developing countries are related to water and sanitation. Despite its importance, water is a finite natural resource and cannot be created. Instead, the hydrologic cycle recycles water through the atmosphere. The fact that our supply is finite has dire implications on our world population of nearly 7 billion people and growing. The global water consumption rate doubles every twenty years, a pace that is double the rate of population growth. If population and consumption trends persist, it is estimated that the demand for water will surpass its availability by 56% and 1.8 billion people will be living in regions of water scarcity by 2025. This situation is exacerbated by the fact that developing countries, already experiencing water-stress, often have the highest population growth ratesbringing more people into a region that already cannot support them. Fresh water and food production are intricately connected; producing one ton of grain requires 1,000 tons of water. Food production is so wholly dependent on water that agriculture can use 75 to 90% of freshwater in a region. Water scarcity creates food shortages, raises food prices, and increases a countries dependence on food imports. This water scarcity, which used to be a local dilemma, has since grown into an international issue. Since producing grain requires large quantities of water, countries have started to cut back on their own grain productionopting to import instead. Thus, the global water market is nearly synonymous with the international grain market. The situation has become so extreme that several of the largest cities worldwideincluding Los Angeles, Cairo, and New Delhican only increase their water consumption by reducing agricultural water use. Nearly every country in the Middle East and North Africa is approaching its water limitturning the region into the worlds fastest growing grain import market.Improving water quality1. REDUCE YOUR LAWNBy creating no-mow zones of native wildflowers, grasses, shrubs, and trees, especially as buffers near ponds and streams. This reduces water, fertilizer, and pesticide use and provides a welcoming habitat for wildlife.

2. FERTILIZE SMARTHave your soil tested before applying fertilizer to your lawn to see if it even needs it. Dont over - fertilize - more is not better. During rainstorms, nutrients from fertilizers can wash off lawns into local waters where the excess nutrients promote algae blooms, including some algae that are harmful to people and pets. Algae blooms cause a decrease in oxygen in the water which endangers aquatic life and can cause fish kills. Use phosphorus fertilizer for new lawns only, unless the soil test shows a need for phosphorus on an established lawn. Sweep up fertilizer that spills on hard surfaces. Leaving grass clippings on your lawn can reduce your fertilizer needs by up to 25%.

3. REDUCE USE OF LAWN AND GARDEN PESTICIDES Investigate use of biological controls and products with natural ingredients. Read the labelsapply the right amount at the right time and be aware of the toxicity warnings.

4. REDUCE RUNOFF Increase the amount of stormwater absorbed into the ground by directing down- spouts onto your lawn, not onto paved surfaces where the runoff could pick up oil, yard waste, and other debris. Install a rain barreluse the water for plantings. Install a rain garden to increase the amount of storm water absorbed into the ground.

5. DONT DRAIN YOUR SWIMMING POOL into storm drains, wetlands, rivers, or ponds. Instead drain it onto the ground away from your drinking water well. Drain your pool only when your test kit does not detect chlorine levels so that it wont harm vegetation. 6. WASH VEHICLES ON YOUR LAWN (Away from your drinking water well) or use a commercial car wash. Washing on your lawn minimizes the amount of dirty, soapy water flowing into the storm drains that run directly into our water bodies. If you are unable to wash your car on your lawn, use only biodegradable, phosphate-free cleaners. If washing near a storm drain, temporarily divert the water towards grassy areas. Commercial car washes typically use far less water, recycle their wash water, and treat their water prior to releasing it into the sewer system. 7. CONSERVE WATER Dont overwater your lawn. Lawns need only one inch of water per week (from either watering or rain). Excessive water use, especially in summer, can dramatically reduce flow in rivers and streams, harming aquatic life. If your house is connected to a public sewer, conserving water will help reduce the discharge from your wastewater treatment facility into local waters AND save you money! If you use a septic system, water conservation helps prevent system failures.NOISE POLLUTIONIntroductionNoise is perhaps one of the most undesirable by products of modern mechanized lifestyle. It may not seem as insidious or harmful as the contamination of drinking water supplies from hazardous chemicals, but it is a problem that affects human health and well-being and that can also contribute to the general deterioration of environmental quality. It can affect people at home, in their community, or at their place of work. Sound waves cause eardrums to vibrate, activating middle and inner organs and sending bioelectrical signals to the brain. The human ear can detect sounds in the frequency range of about 20 to 20,000 Hz, but for most people hearing is best in the range of 200 to 10,000 Hz. A sound of 50 Hz frequency, for example, is perceived to be very low-pitched, and a 15,000 - Hz sound is very high pitched. Simply defined, noise is undesirable and unwanted sound. It takes energy to produce sound, so, in a manner of speaking, noise is a form of waste energy. It is not a substance that can accumulate in the environment, like most other pollutants, but it can be diluted with distance from a source. All sounds come from a sound source, whether it be a radio, a machine, a human voice, an airplane, or a musical instrument. Not all sound is noise. What may be considered music to one person may be nothing but noise to another. To a extent, noise pollution is a matter of opinion. Noise is measured in terms of Decibel units. Sources of noise Based on the type of noise include a) Industrial Noise b) Transport Noise c) Neighbourhood Noise.a) Industrial Noise: It is caused by machines used for the technological advancement. There exist a long list of sources of noise pollution including different machines of numerous factories, industries and mills.b) Transport Noise: Main source is transport. In addition to adversely impacting urban air quality, heavy automobile traffic creates seemingly unbearable noise pollution. Ever since industrial revolution doubling of noise for every 10 years.Measurement of noiseThe noise is usually measured either by i) Sound Pressure or ii) Sound Intensity. The Sound intensity is measured in Decibel (dB), which is tenth part of the longest unit Bel named after Alexander Graham Bell. Decibel (dB) is a ratio expressed as the logarithmic scale relative to a reference sound pressure level. The db is thus expressed as Intensity Measured (I) Sound Intensity Level = 10 log ----------------------------------- Reference intensity (I0) or dB = 10 log I / I0

Problems of noise and program for tackling it1. Auditory fatigue -- Whistling & buzzing in ears( noise level - 90dB) Deafness -- Permanent hearing loss (noise level- 100dB)2. Tinnitus Persistent sound in one or both ears. Tinnitus is often experienced as a high-pitched hiss, ring, buzz, or roar. It is usually continuous, but it may pulsate, and the beats may coincide with the heartbeat. 3. Non auditory effects Interference with speech communication - 50dB Annoyance, ill temper, bickering loss in working efficiency - tiredness, deterioration or complete loss of ability to work 4. Physiological disorders Neurosis, anxiety, hypertension, increased sweating, giddiness, nausea, fatigue, visual disturbance, reduces depth and quality of sleep , peptic ulcers, Increases cholesterol level resulting in constriction of blood vessel , Low weight children to mothers.

5. Even the nonliving things such as buildings undergo physical damage by cracks, breakage of windows, doors, and glasses etc. by sudden and explosive sounds.

Control of Noise PollutionNoise definitely affects the quality of life. It is therefore important to ensure the mitigation or control of noise pollution. Noise pollution can be controlled At source level Can be done by i) Designing and fabricating silencing devices in air craft engines, automobiles industrial machines and home appliances, ii) By segregating the noisy machines During Transmission can be achieved by adding insulation and sound-proofing to doors, around industrial machinery. Zoning urban areas to maintain a separation between residential areas and zones of excessive noise. Sound a) Acoustillite : made up of Compressed wood pulp, wood fibers and is available in the form of tiles b) Acoustical blanket : Prepared from mineral wool or glass fibres c) Hair Felt: Consists of wool fibres, Coarse Cotton Fibres. d) Fibre Glass e) Cork Carpet: Prepared out of pieces of corks treated with linseed oil and is used for covering floors. f) Acoustic Plaster: Mainly consists of gypsum in the form of plaster. Protecting the exposed person By creating vegetation cover Plants absorb and dissipate sound energy and thus act as Buffer Zone. Trees should be planted along highways, schools and other places. Planting vegetation to absorb and screen out noise pollution Trees can act as a noise barrier Through law a) Silence Zones must be created near Schools, hospitals b) Indiscriminate use of loudspeakers at public places should be banned/ restricted by laws c) Restriction on unnecessary us e of horns and vehicles plying without silencersd) Restrictions on aircraft flight at midnight Through education - We Indians are Noisy people. Every occasion, it may be religious or family functions or elections; we used to celebrate with noise. Educating the people that noise is a pollutant, not a part of our routine life.

UNIT 4Social Issues in Environment

Sustainable developmentThe world commission on environment and development in its report to the United Nations in 1987 defined sustainable development as meeting the needs of the present generation without compromising the ability of future generation to meet their own needs. For sustainability to occur, advance technology in process control, product design and monitoring are essential for efficient use of resources in production while simultaneously abating pollution. The objective of all these efforts is the quest for zero pollutant emissions from the industrial processes. Following schemes from this new strategy are:1. Prevention of pollution: it is a proactive multimedia management approach to achieve front end reduction of pollutants in the waste streams by strictly controlling the industrial processes with respect to process upsets, undesirable emission and by improving the product quality, reducing loss of raw material to the waste effluents and recycling the by-products. Pollution prevention also eliminates the transfer of pollutants from one media to another because pollutants are not generated in the first place. 2. Design for eco-friendly environment: Besides pollution control during industrial processes, it is also essential to check the overall synthetic sequence in the production of chemical substances and to consider the substitution or elimination of hazardous chemicals wherever possible. In view of the new emphasis on pollution prevention by both the industry and regulatory agencies and also due to the huge cost of treatment, disposal and compliance, selection of any synthetic scheme solely on the bass of yield is no longer, valid. All the scientific, environmental and economic impact should be incorporated into the synthetic scheme being selected to ensure environmentally benign synthesis of a chemical substance. Thus, the paradigm shift for the future emphasises pollution prevention by ensuring that industrial processes run under tight control, substitute less hazardous chemicals and recycle by-products or designs new production processes which are environmentally benign. The future challenge is to shift from the present environmental policy based on pollution controls and government mandated regulations to a new and more realistic environmental policy based on pollution prevention, source reduction, recycling and waste minimisation.

Urbanisations and problems1. Urban Sprawl: Urban sprawl or real expansion of the cities, both in population and geographical area, of rapidly growing cities is the root cause of urban problems. In most cities the economic base is incapable of dealing with the problems created by their excessive size. Massive immigration from rural areas as well as from small towns into big cities has taken place almost consistently; thereby adding to the size of cities.This is due to the fact that such large cities act as magnets and attract large number of immigrants by dint of their employment opportunities and modern way of life. Such hyperurbanisation leads to projected cities sizes of which defy imagination. Delhi, Mumbai, Kolkata, Chennai, Bangalore, etc. are examples of urban sprawl due to large scale migration of people from the surrounding areas.In several big cities wealthy people are constantly moving from the crowded centres of the cities to the more pleasant suburbs where they can build larger houses and enjoy the space and privacy of a garden around the house. In some cities, the outskirts are also added to by squatters who build makeshift shacks of unused land although they have no legal right to the land. The difficulty of restricting town growth in either case is immense and most towns and cities are surrounded by wide rings of suburbs.2. Overcrowding:Overcrowding is a situation in which too many people live in too little space. Overcrowding is a logical consequence of over-population in urban areas. It is naturally expected that cities having a large size of population squeezed in a small space must suffer from overcrowding. This is well exhibited by almost all the big cities of India.Delhi has a population density of 9,340 persons per sq km (Census 2001) which is the highest in India. This is the overall population density for the Union territory of Delhi. Population density in central part of Delhi could be much higher. This leads to tremendous pressure on infrastructural facilities like housing, electricity, water, transport, employment, etc. Efforts to decongest Delhi by developing ring towns have not met with the required success.3. Housing:Overcrowding leads to a chronic problem of shortage of houses in urban areas. This problem is specifically more acute in those urban areas where there is large influx of unemployed or underemployed immigrants who have no place to live in when they enter cities/towns from the surrounding areas.For about a third of urban Indian families, a house does not include a kitchen, a bathroom, a toiletand in many cases there is no power and water supply. Only 79 per cent (42.6 million) urban household live in permanent (pucca) houses. 67 per cent (36 million) of the urban houses are owned by the households while 29 per cent (15 million) are rented.Several factors are responsible for the above mentioned sad state of affairs with respect to housing problems faced by the urban people. The major factors are shortage of building materials and financial resources, inadequate expansion of public utilities into sub-urban areas, poverty and unemployment of urban immigrants, strong caste and family ties and lack of adequate transportation to sub-urban areas where most of the vacant land for new construction is located.4. Unemployment:The problem of unemployment is no less serious than the problem of housing mentioned above. Urban unemployment in India is estimated at 15 to 25 per cent of the labour force. This percentage is even higher among the educated people.One of the major causes of urban unemployment is the large scale migration of people from rural to urban areas. Rural-urban migration has been continuing for a pretty long time but it has not always been as great a problem as it is today. The general poverty among the rural people pushes them out to urban areas to migrate in search of livelihood and in the hope of a better living.5. Slums and Squatter Settlements: The natural sequel of unchecked, unplanned and haphazard growth of urban areas is the growth and spread of slums and squatter settlements which present a striking feature in the ecological structure of Indian cities, especially of metropolitan centres.The rapid urbanisation in conjunction with industrialisation has resulted in the growth of slums. The proliferation of slums occurs due to many factors, such as, the shortage of developed land for housing, the high prices of land beyond the reach of urban poor, a large influx of rural migrants to the cities in search of jobs etc.6. Transport: With traffic bottleneck and traffic congestion, almost all cities and towns of India are suffering from acute form of transport problem. Transport problems increase and become more complex as the town grows in size. With its growth, the town performs varied and complex functions and more people travel to work or shop.The traffic scenario in almost all the Indian cities presents a pathetic picture with Mumbai still having the best city transport system and Chennai, Ahmedabad and Pune being reasonably well served by local transport system. In all other cities, if one does not own a personal vehicle, great hardship is experienced in moving about in the city.Apart from that, the level of incomes and affordability of Indian masses is very low and the citizens are not able to pay an economic fare for use of public transport system. Therefore, all city bus services sustain such heavy losses that they cannot really expand or even maintain a fleet adequately to meet the city needs.Moreover, mixture of vehicles causes uncontrollable chaos on the roads. Free movement of stray cattle and domestic animals on the roads adds to traffic problem and often cause accidents. Heavy traffic and congestion leads to slow movement of traffic, fuel wastage environmental pollution and loss of precious time.7. Water: What is one of the most essential elements of nature to sustain life and right from the beginning of urban civilisation, sites for settlements have always been chosen keeping in view the availability of water to the inhabitants of the settlement. However, supply of water started falling short of demand as the cities grew in size and number.Today we have reached a stage where practically no city in India/ gets sufficient water to meet the needs of city dwellers. In many cities people get water from the municipal sources for less than half an hour every alternate day. In dry summer season, taps remain dry for days together and people are denied water supply at a time when they need it the most.Sadly majority of the cities and towns do not get the recommended quantity of water. Gap in demand and supply of water in four metro cities, viz., Mumbai, Kolkata, Delhi and Chennai varies from 10 to 20 per cent. The condition is still worse in small cities and towns. To meet the growing demand for water, many cities are trying to tap external sources of water supply.8. Sewerage Problems: Urban areas in India are almost invariably plagued with insufficient and inefficient sewage facilities. Not a single city in India is fully sewered. Resource crunch faced by the municipalities and unauthorised growth of the cities are two major causes of this pathetic state of affairs.According to latest estimates, only 35-40 per cent of the urban population has the privilege of sewage system. Most of the cities have old sewerage lines which are not looked after properly. Often sewerage lines break down or they are overflowing.Most cities do not have proper arrangements for treating the sewerage waste and it is drained into a nearly river (as in Delhi) or in sea (as in Mumbai, Kolkata and Chennai), thereby polluting the water bodies.9. Trash Disposal:As Indian cities grow in number and size the problem of trash disposal is assuming alarming proportions. Huge quantities of garbage produced by our cities pose a serious health problem. Most cites do not have proper arrangements for garbage disposal and the existing landfills are full to the brim. These landfills are hotbeds of disease and innumerable poisons leaking into their surroundings.Wastes putrefy in the open inviting disease carrying flies and rats and a filthy, poisonous liquid, called leachate, which leaks out from below and contaminates ground water. People who live near the rotting garbage and raw sewage fall easy victims to several diseases like dysentery, malaria, plague, jaundice, diarrhoea, typhoid, etc.10. Urban Crimes:Modem cities present a meeting point of people from different walks of life having no affinity with one another. Like other problems, the problem of crimes increases with the increase in urbanisation. In fact the increasing trend in urban crimes tends to disturb peace and tranquility of the cities and make them unsafe to live in particularly for the women.Growing materialism, consumerism, competition in everyday life, selfishness, lavishness, appalling socio-economic disparities and rising unemployment and feeling of loneliness in the crowd are some of the primary causes responsible for alarming trends in urban crime.Not only the poor, deprived and slum dwellers take to crime; youngsters from well-to-do families also resort to crime in order to make fast buck and for meeting requirements of a lavish life. Occasional failures in life also drag youngsters to crime.The problem of urban crime is becoming more complicated in the present day world because criminals often get protection from politicians, bureaucrats and elite class of the urban society. Some of the criminals reach high political positions by using their money and muscle power.

Climate change and global warming acid rain and ozone depletion Climate means the average pattern in which weather varies in time. The climate of a region depends on the presence & absence of water, the reflection of solar radiation, the ability to transfer water to the atmosphere (evaporation), the capacity to store heat, topography and texture of the region.

CLIMATE EFFECTS

Green House Effect and Global Warming

The term Greenhouse effect, first coined by J. Fourier in 1827, is also called global warming, atmospheric effect or carbon di oxide problem. Green house means a building made of glass, with heat and humidity regulated by plants. It may be defined as follows:1. Greenhouse effect is progressive warming up of the earths surface due to blanketing effect of man-made carbon di oxide in the atmosphere.2. Greenhouse effect is the phenomenon due to which the earth retains heat.3. Greenhouse effect means the excessive presence of those gases blocked in the radiation from the earth surface to the atmosphere leading to an increase in temperature, which in turn would make life difficult on earth.

Global Warming and climate changesThe climate system consists of the atmosphere, the hydrosphere, the cryosphere, the lithosphere and the biosphere. Disturbance in any one system will affect the others. Natural factors such as solar radiation changes and volcanic activity have contributed to hot years, such as 1990, 1994, 1997, 1998. Consequences of global warming:1. The highest air temperature increases are expected to occur in the northern hemisphere at high latitudes as a result of a substantial reduction in the amount of sea ice and snow cover on the land because of the warming. Normal sea ice acts as a thermal blanket between the water and the air.2. Plants will respond favourably to increased carbon di oxide concentrations by increasing rates of photosynthesis. If carbon di oxide concentration doubles, photosynthetic rates in most cases will increase from 20-50%.3. All agricultural crops will respond favourably to increasing atmospheric concentrations of carbon di oxide and these responses will be affected by the benefits or difficulties caused by increased temperatures.4. The climate changes anticipated In a warmer world are quite different. Low latitudes will have the least amount of warming and the high latitudes the most. 5. Wheat yield will decrease with increase in temperature but increasing levels of carbon di oxide may mitigate this and stabilise yields.6. Warming up of earth will make the ice at poles to be increasingly converted to water resulting in rise in world sea level.

Environmental legislation for hotel industry-environment protection act

The Environment (Protection) Act 1986 The environment protection act 1986 was enacted as per the spirit of the Stockholm conference held in June 1972 to take appropriate steps for the protection and improvement to prevent hazards to human beings, living creatures and property. This act ensures enforcement of several acts or regulations concerning pollution control. It empowers the central government to issue directions:1. For the closure, prohibition of any industry, operation and process.2. For the stoppage or regulation of the supply of water, power or any other service, even without obtaining court orders.The act also empowers the central government to make rules for the first time for the:1. Standard of quality of air, water and soil for various areas and for various purposes.2. Maximum permissible limits of concentration for various environmental pollutants (including noise) for different areas.3. Procedures and safeguards for handling of toxic substances4. Prohibition and restrictions on the location of industries and carrying out operations5. Procedures and safeguards for prevention of accidents which may cause environmental pollution.6. Providing for remedial measures in case of accidents.

Issues involved in enforcement of environmental legislation:1. Although the legislative measures taken and the administrative setup are sufficiently indicative of the governments concern, the implementation does not reflect a sound appreciation of the issues involved in eco management and development.2. Environment is a resource, the most precious of all the earths resources. The measures adopted by the government until now do not reveal an equal emphasis on the management and development aspects of this vital resource.3. The more modern view is that law must guide and help people and establish a trend of acceptance.4. Environmental litigation is more expensive than other types of disputes; sincerity involves expert testimony and technical evidence.5. There is nothing fundamentally wrong with out of court settlement of environmental disputes. But in India, officially initiated and sanctioned out of court settlements may aggravate the perennial problem of corruption.6. Sharing the cost of antipollution measures taken by the industry seems to be a better strategy than state sponsored expensive and lengthy prosecutions.