Construction of a Nicol prism:

1.A calcite crystal whose length is 3 times as its width is taken.

2.The end faces of the crystal are  polished in such a way that the angles of the principal section become 68⁰  and 112⁰ instead of 71⁰ and 109 ⁰ due to increase the field of view.

3.The crystal is cut in to two pieces along the optic axis or perpendicular to the opposite faces PR and QS.

4.The two cut surfaces are polished and then cemented by Canada balsam.

5.The refractive index of Canada balsam is intermediate between the refractive index of ordinary ray and extraordinary ray for calcite.

  refractive index of ordinary ray             =1.658

  refractive index of Canada balsam        =1.55

  refractive index of extra ordinary ray   =1.486

TYPES OF INTERFERENCE:                                                                                                               There are two types of Interference. 1.Constructive Interference.
                                                       2.Destructive  Interference.                                                                    

COHERENT SOURCES:                                                                                                                Those sources of light which emit light waves continosly of same wavelength,timeperiod,frequency and amplitude and have zero phase difference or constant phase difference are coherent sources.

Multidisciplinary nature of Environmental Studies

The word environment is derived from the French verb ‘environner’ which means to ‘encircle or surround’. Thus our environment can be defined as the physical, chemical and biological world that surround us as well as the complex of social and cultural conditions affecting an individual or community. This broad definition includes the natural world and the technological environment as well as the cultural and social contexts that shape human lives. It includes all factors living and nonliving that affect an individual organism or population at any point in the life cycle; set of circumstances surrounding a particular occurrence and all the things that surrounds us.

Objective of this course is to develop concern for our own environment which will lead us to act at our own level to protect the environment we all live in. There are three reasons for studying the state of the environment. The first, is the need for information that clarifies modern environmental concepts like equitable use of natural resources, more sustainable life styles etc. Second, there is a need to change the way in which we view our own environment, using practical approach based on observation and self learning. Third, there is a need to create a concern for our environment that will trigger pro-environmental action, including simple activities we can do in our daily life to protect it. Environmental science is essentially the application of scientific methods and principles to the study of environmental issues, so it has probably been around in some

forms as long as science itself. Environmental science is often confused with other fields of related interest, especially ecology, environmental studies, environmental education and environmental engineering. Environmental science is not constrained with any one discipline and it is a comprehensive field. Environmental science is not ecology though that discipline may be included. Ecologists are interested in the interactions between some kind of organisms and its surroundings. Most ecological research and training does not focus on environmental problems except as those problems impact the organism of interest. Environmental scientists may or may not include organisms on their field of view. They mostly focus on the environmental problem which may be purely physical in nature. For eg. Acid deposition can be studied as a problem of emissions and characteristic of the atmosphere without necessarily examining its impact on organisms.

There are two types of environments:

1. Natural environment

2. Man made environment

Natural: The environment in its original form without the interference of human beings is known as natural environment. It operates through self regulating mechanism called homeostasis i.e, any change in the natural ecosystem brought about by natural processes is counter balanced by changes in other components of environment.

Man made or Anthropogenic Environment: The environment changed or modified by the interference of human beings is called man made environment. Man is the most evolved creature on this earth. He is modifying the environment according to his requirements without bothering for its consequences. Increased technologies and population explosion are deteriorating the environment more and more.

Scope of environmental studies:

Because, the environment is complex and actually made up of many different environments, including natural, constructed and cultural environments, environmental studies is the inter disciplinary examination of how biology, geology, politics policy studies, law, geology, religion engineering, chemistry and economics combine to inform the consideration of humanity’s effects on the natural world. This subject educates the students to appreciate the complexity of environmental issues and citizens and experts in many fields. By studying environmental science, students may develop a breadth of the interdisciplinary and methodological knowledge in the environmental fields that enables them to facilitate the definition and solution of environmental problems. The scope of environmental studies is that, the current trend of environmental degradation can be reversed if people of educated communities are organized and empowered; experts are involved in sustainable development. Environmental factors greatly influence every organism and their activities. The major areas in which the role of environmental scientists are of vital importance are natural resources, ecosystems, biodiversity and its conservation, environmental pollution, social issues and environment human population and environment. It is essentially a multidisciplinary approach and its components include Biology, Geology, Chemistry, Physics, Engineering, Sociology, Health Sciences, Anthropology, Economics, Statistics and Philosophy It is essentially a multidisciplinary approach. An Understanding of the working of the environment requires the knowledge from wide ranging fields. The table below shows a list of topics dealt commonly in air pollution and the related traditional fields of knowledge illustrating the interdisciplinary nature of the subject.

Importance of environmental education:

Environment is not a single subject, it is an integration of several subjects that include both science and social studies. To understand all the different aspects of our environment, we need to understand biology, chemistry, physics, geography, resources management, economics, and population issues. Thus, the scope of environmental studies extremely wide and covers some aspects of nearly every ma jor discipline. We live in a world where natural resources are limited. Water, air, soil, minerals, oils, the products we get from forests, grasslands, oceans and from agriculture and live stock, are all a part of our life support systems. Without them, life itself would be impossible. If we use them more and more, the earth’s resources must inevitably shrink. The earth cannot be expected to sustain indefinitely due to over utilization of resources, misuse of resources. We waste or pollute large amount of clean water. We discard plastic, solid wastes and liquid wastes from industries which cannot be managed by natural processes. These accumulate in our environment, leading to a variety of diseases and other adverse environmental impacts, now seriously affe cting all our lives. Air pollution leads to respiratory diseases, water pollution to gastro – intestinal diseases and many pollutants are known to cause cancer. This situation will only improve if each of us begins to take action in our daily lives that will help to preserve our environmental resources. We cannot expect Government alone to manage the safeguarding of the environment, nor we can expect other people to prevent environmental damage. We need to do it ourselves. It is a responsibility that each of us must take on as one’s own. Environmental Issues of Global Concern The main environmental issues today are wide ranging and all-encompassing are deforestation, biodiversity, soil erosion, climate change, pesticide build-up, industrial and municipal pollution. All these problems can be categorized into three main issues:

1. Population explosion

2. Land degradation

3. Environmental pollution: Industrialization, agriculture/fertilizer/pesticide/green house gases, air pollution, acid rain, ozone depletion, green house effect, water pollution and deforestation.

Environmental problems in India can be put into three classes: Poverty, problems arising as negative effects of the very process of development and problems arising from improper implementation of the directives and laws of environmental protection

Values of Nature: This can be discussed under three categories i.e. i) Productive value, ii) Aesthetic value or recreational value and iii) Option value.  

Productive value of nature : Worlds’ species contain an incredible and unaccountable number of complex chemicals. These are raw materials used for developing new medicines and industrial products. When we permit the destruction of a forest, wet land or other natural area and do not protest about it, future generations are being denied the use of these valuable resources. Thus the urgent need to protect all living species is a concept that we need to understand and act upon. There is close link between agriculture and the forest, which illustrates its productive value. For crops to be successful, the flowers of fruit trees and vegetables must be pollinated by insects and birds. Their life cycle frequently require intact forests.   

Aesthetic/ recreational value of nature : Nature encompasses every aspect of living (biodiversity: flora and fauna) and non- living (sea, desert) part of the earth and it enlivens our existence on earth. This is created by developing national parks and wildlife sanctuaries in relatively undisturbed areas. In an Urban setting, there will be green spaces and gardens – psychological and physical health of city dwellers and provides aesthetic value and visual appeal. It also gives access to certain amount of peace. Nature tourism or wildlife tourism or eco tourism is a pleasurable experience and also creates a deep respect and love for nature.

The option value of nature :

Nature provides us with various options on how we utilize its goods and services. This is its option value. We can use up goods and services greedily and destroy its integrity and long term values or we can use its resources sustainably and reduce our impact on environment. The option value allows us to use its resources sustainable and preserve its goods and services for the future. “The earth provides enough to satisfiy every persons need but not every persons greed” is the vision of Mahatma Gandhiji. 

Need for public awareness:

As the earth’s natural resources are rapidly dwindling and our environment is being increasingly degraded by human activities, it is evident that some thing needs to be done. The following measures may help for the environmental awareness.

1. Join a group to study nature, such as WWF-1 or BNHS or another environmental group

2. Begin reading news paper articles and periodicals like Down to Earth, WWF-1 News letter, BNHS, Hornbill, Sanctuary magazine etc which will tell you more about our current environmental issues. There are also several environmental websites.

3. Lobby for conserving resources by taking up the cause of environmental issues during discussions with friends and relatives. Practice and promote issues such as saving paper, saving water, reducing use of plastic, practicing the 3Rs principle of reduce, reuse, recycle and proper waste disposal. 

4. Join local movements that support activities like saving trees in your area, go on nature treks, recycle waste, buy environmentally friendly products.

5. Practice and promote good civic sense and hygiene such as enforcing no spitting or tobacco chewing, no throwing garbage on the road, no smoking in public places, no urinating or defecating in public places.

6. Take part in events organized on World Environment Day, Wildlife Week etc.

7. Visit a National Park or Sanctuary or spend time in whatever natural habitat you have near your home.

Institutions in environment

Managing natural resources require efficient institutions at all levels i.e. local, national, regional and global. Institutions, as defined by Young (1999), are systems of rules, decision- making procedures, and programs that give rise to social practices, assign roles to participants in these practices, and guide interactions among theoccupants of the relevant roles. Institutions often figure prominently in efforts to solve or manage environmental problems. Several Government and Non- Government Organizations (NGO’S) are working towards environmental protection in our country. They play a role both in causing and in addressing problems arising from human-environment interactions. They have led to a growing interest in environmental protection and conservation of nature and natural resources. Among the large number of institutions that deal with environmental protection and conservation, a few well-known organization include government organizations like the BSI and ZSI, and NGOs like the BNHS, WWF-1, etc.

The Bombay Natural History Society (BNHS), Mumbai: It was founded on 15 September 1883, is one of the largest non-governmental organizations in India engaged in conservation and biodiversity research. It supports many research efforts through grants, and publishes a popular magazine called the Hornbill and also an internationally well-known the Journal of the Bombay Natural History Society. Its other publications include salim Ali’s Handbook on Birds, JC Daniel Book of Indian reptiles. SH Prater’s book of Indian mammals and PV Bole’s book of Indian trees. Many prominent naturalists, including the ornithologists Sálim Ali and S. Dillon Ripley have been associated with it. The BNHS has over the years helped the government to frame wildlife-related laws and has taken up battles such as the ‘save the silent valley’ campaign.

World Wide fund for nature- India (WWF-1), New Delhi: The WWF-1 was initiated in 1969 in Mumbai, after which the headquaters were shifted to Delhi with several State, Divisional and Project offices spread across India. In the early years it focused attention on wildlife education and awareness. It runs several programs, including the nature clubs of India program for school children and works as a think –tank and lobby force for environmental and development issues.

Centre or science and environment (CSE), New Delhi: is a public interest research and advocacy organisation based in New Delhi. CSE researches into, lobbies for and communicates the urgency of development that is both sustainable and equitable. It has published a major document on the State of India’s Environment, the first of its kind to be produced as a citizen’s Report on the environment. It also publishes a popular magazine, Down to Earth which is a science and environment fortnightly. It is involved in the publication of material in the form of books posters, video films and also conducts workshops and seminars on biodiversity- related issues. The Centre’s efforts are built around five broad programmes: Communication for Awareness, Research and Advocacy, Education and Training, Knowledge Portal and Pollution Monitoring.

C.P.R Environmental Education Centre, Madras: the CPR-EEC was set up in 1988 CPREEC) is a Centre of Excellence of the Ministry of Environment and Forests (MoEF), Government of India, established jointly by the Ministry and the C.P. Ramaswami Aiyar Foundation. It conducts a variety of programs to increase awareness and knowledge of public i.e., school children, local communities, woman as main key target groups about the various aspects of environment Its programs include components on wildlife and biodiversity issues. CPR-EEC also publishes large number of text books for school children and video-on wheels for rural public. The C. P. R. Environmental Education Centre received the Indira Gandhi Paryavaran Puraskar for the year 1996.

The Centre for Environment Education (CEE) in India was established in August 1984 as a Centre of Excellence supported by the Ministry of Environment and Forests. The organisatio n works towards developing programmes and materials to increase awareness about the environment and sustainable development. The head office is located in Ahmedabad. The Centre has 41 offices including regionalcells and several field offices, across India.. It has international offices in Australia, Bangladesh and Sri Lanka. CEE's primary objective is to improve public awareness and understanding of the environment with a view to promoting the conservation and sustainable useof nature and natural resources, leading to a better environment and a better quality of life. To this end, It undertakes demonstration projects in education, communication and development that endorse attitudes, strategies and technologies which are environmentally sustainable. CEE is committed to ensuring that due recognition is given to the role of education in the promotion of sustainable development.

Bharati Vidyapeeth University, Institute of Environment Education & Research,

Pune was established in 1993.This is part of the Bharati Vidyapeeth deemed University. Its major focus is to spread the message of the need for pro-environmental action in society at large through a dual strategy of formal and non –formal integrated activities. BVIEER is a one of a kind institution that caters to the need of Environment Education at all levels - PhD, M.Sc and Diploma. The distinctive characteristics of BVIEER are its wide mandate of teaching, research and extension. It implements a large outreach program that has covered over 435 schools in which it trains teachers and conduct fortnightly environment education programs. Biodiversity conservation in a major focus of its research initiatives. It develops low-cost interpretation centers for natural and architectural sites that are highly locale-specific as well as a large amount of innovative environment educational material for a variety of target groups. It has developed a teachers handbook linked to school curriculum and a textbook for UGC for the compulsory undergraduate course on environment. Its director has developed a CD-ROM on India’s biodiversity.

The Salim Ali Center for Ornithology and Natural History (SACON): - It is an autonomous organization with headquarters at Coimbattore. It is a national centre for information, education and research in ornithology and natural history in India. This institution was Dr. Salim ali’s dream, which became a reality only after his demise and was named in honor of Salim Ali, the leading pioneer of ornithology in India. Its mission is "To help conserve India’s biodiversity and its sustainable use through research, education and peoples’ participation, with birds at the centre stage".

Wild life Institute of India (WII), Dehradhun: Is an autonomous institution of MoEF, GOI, established in 1982. It is an internationally acclaimed Institution, which offers training program, academic courses and advisory in wildlife research and management. The Institute is actively engaged in research across the breadth of the country on biodiversity related issues. Its most significant publication has been ‘Planning wild life and protected area network for India (Rodgers and Panwar,1988).It has environment impact assessment cell. It trains personnel in ecodevelopment, wildlife biology, habitat management and nature interpretation.

Zoological survey of India (ZSI): is a premier organisation in zoological research and studies. The activities of the ZSI are coordinated by the Conservation and Survey Division in the MoEF, GOI. This is the only taxonomic organization in the country involved in the study of all kinds of animals from Protozoa to Mammalia, occurring in all possible habitats from deepest depth of the ocean to the peaks of Himalaya, was

established on 1st July, 1916 to promote survey, exploration and research leading to the advancement in our knowledge of the various aspects of the exceptionally rich animal life. It has over the years collected type specimens on the basis of which our animal’s life has been studied over the years. Its origins were collections based at the Indian museum at Calcutta, which was established in 1875. The older collections of the Asiatic society of Bengal and of the Indian museum were also transferred to the ZSI. Today, it has over a million specimens. This makes it one of the largest collections in Asia. It currently operated from 16 regional centers.

The madras Crocodile Bank Trust (MCBT): MCBT, the first crocodile conservation breeding in Asia, was founded in 1976 to conserve Indian crocodilians and establish program for the conservation and propagation of other species of endangered reptiles Head quarters are at Madras. Over years, over 1500 crocodiles and several hundred eggs have been supplied to various state forest departments for restocking programmes in the wild, and for setting up breeding facilities in other state in India and neighboring countries. It is the one which started the first sea turtle surveys and conservation program in India, including a sea turtle hatchery. It is involved in environmental education programs for the villages and schools that include nature camps, training workshop for teachers and youth from fishing villages.

The Andaman and nicobar islands Environmental team (ANET) a division of the MCBT was constituted in 1992. A base was set up by Harry Andrews in south Andaman for herpetological and other ecological studies in these islands. The Crocodile bank is thesite of the irula Snake catchers’ cooperative society, which is an adivasi self- help project and supplies all of India’s snake and scorpion venom needed for the production of antivenom and for medical use. MCBT personal also initiated the Irula Tribual Women’s welfare society, which is primarily a society for reforestation of wastelands and incomegeneration

projects for irula women.

Uttarkhand seva nidhi (USKN), Almora : It is a public charitable trust founded in 1967.This organization was appointed as a nodal agency in 1987 by the Department of Education, Ministry of Human Resources Development, Government of India to undertake locale-specific environmental education programmes both in rural schools and villages in the hill districts of Uttar Pradesh, now Uttaranchal. Subsequently, a research and resource centre, the Uttarakhand Environmental Education Centre (UEEC), was set up in 1993, also with support from the Department of Education. As activities continued to increase, a separate organisation, the Uttarakhand Seva Nidhi Paryavaran Shiksha Sansthan (USNPSS), a registered society, was set up in 1999 to handle all the environmental activities of the Nidhi. As Uttaranchal is a fragile ecological zone where human activities can cause extensive land degradation (deforestation and soil erosion) if not carried out in an environmentally-sound manner. The organization conducts education, training and on the spot problem solving programmes with the aim of helping people to understand their surroundings from a broad ecological point of view and encourage them to organise themselves to deal with environmental problems that affect their daily lives, and to provide training in technical know-how and practical skills. Its main target is sustainable resource use at the village level through training school children. Its environment education program covers about 500 schools.

Kalpavriksh: This NGO, initially Delhi-based, is now working from pune and is active in several other parts of India. Kalpavriksh worked on a variety of fronts: education and awareness; investigation and research; direct action and lobbying, and litigation with regard to environment and development issues. Its activities include talks and audiovisuals in schools and colleges, nature walks and outstation camp, organizing student participation in ongoing campaigns including street demonstrations, pushing form consumer awareness regarding organic food, press statements, handling green alerts, and meeting with city administrators. Kalpavriksh was among those responsible for developing India’s National Biodiversity Strategy and action plan in 2003. The Botanical Survey of India (BSI) is an institution set up by the Government of India in 1887 to survey the plant resources of the Indian empire. The Botanical Survey was formally instituted on 13 February 1890 under the direction of Sir George King, who had been superintendent of Royal Botanic Garden, Calcutta since 1871. King became the first ex-officio Director of BSI. Presently, it has nine regional centres. It carries out surveys of plant resources in different regions. It monitors botanical resources by analyzing their occurrence, distribution, ecology, economic utility, conservation, environment impact, etc.

People in environment

There are several internationally known environmental thinkers. Among those who have made landmark contributions include Charles Darwin, Ralph Emerson, Henry Thoreau, John Muir, Aldo Leopold, Rachel Carson and EO Wilson. Each of these thinkers looked at the environment from a completely different perspective.

Charles Darwin: wrote the origin of species, which brought to light the close relationship between habitats and species. It brought about a new way of thinking about man’s relationship with other species that was based on evolution. Ralph Emerson: spoke of the dangers of commerce to our environment way back in the

1840s.

Henry Thoreau: in the 1860s wrote that the wilderness should be preserved after he hadlived in the wilderness for a year. Thoreau had many theories and beliefs, which he poured out in his journals and books. Among these was the concept of human ecology: of the relationship between humans and nature. He saw unity and community as important aspects of nature, and he saw all disturbances in these links as caused by human beings. “Thank God men cannot fly, and lay waste the sky as well as the earth” is his famous quotation.

John Muir: He was a Scottish-born American naturalist, author, and early advocate of preservation of wilderness in the United States. His letters, essays, and books telling of his adventures in nature, especially in the Sierra Nevada mountains of California, have been read by millions. His activism helped to save the Yosemite Valley, Sequoia National Park and other wilderness areas. He is remembered as having saved the great ancient sequoia trees in California’s forests. In the 1890s he formed the ‘Sierra club’, which is major conservation NGO in the USA.

Aldo Leopold: was a forest official in the US in the 1920s. He designed the early policies on wilderness conservation and wildlife management. He was considered the father of wildlife ecology and a true Wisconsin hero. His book, ‘A Sand County Almanac’ is acclaimed as the century's literary landmark in conservation, which guided many to ‘live in harmony with the land and with one another’. 

Rachel Carson : was an American marine biologist and conservationist whose writings are credited with advancing the global environmental movement. She was nature writer, and some of the books like ‘The Sea Around Us’ and ‘The Edge of the Sea’ are to her credit. In the late 1950s, Carson turned her attention to conservation and the environmental problems caused by synthetic pesticides. Then in 1962, she wrote ‘Silent

Spring’ , which was met with fierce denial from chemical companies, spurred a reversal in national pesticide policy—leading to a nationwide ban on DDT and other pesticides— and the grassroots environmental movement the book inspired led to the creation of the Environmental Protection Agency. Carson was posthumously awarded the Presidential Medal of Freedom by Jimmy Carter.

EO Wilson: is an entomologist who envisioned that biological diversity was a key to human survival on Earth. He wrote ‘Diversity of life’ in 1993, which was awarded a prize for the best book published on environmental issues. He emphasised the risks to mankind due to man made disturbances in natural ecosystems that are leading to the rapid extinction of species at the global level. There are several individuals who have been instrumental in shaping the environmental history of our country. To name a few with their significant contributions goes as follows:

Salim Ali: was an Indian ornithologist and naturalist, Known as the "birdman of India", Salim Ali was among the first Indians to conduct systematic bird surveys across India. He was instrumental in creating the Bharatpur bird sanctuary (Keoladeo National Park) and prevent the destruction of what is now the Silent Valley National Park. He was awarded India's second highest civilian honour, the Padma Vibhushan in 1976. His autobiography, fall of a sparrow , should be read by every nature enthusiast. He was our country’s leading conservation scientist and influenced environmental policies in our country for over 50 years.

Smt. Indira Gandhi: as PM played a very significant role in the preservation of India’s wildlife. It was during her period as PM, that the network of protected areas (PAs) grew from 65 to 298 and the wildlife protection act was formulated. The Indian Board of wildlife was extremely active as she personally chaired all its meetings.

S P Godrej was one of Inida’s greatest supports of wildlife conservatio n and nature awareness programs. Between 1975 and 1999 SP Godrej received 10 awards for his conservation led to his playing a major advocacy role for wildlife in India.

M. S. Swaminathan: He has founded the MS Swaminathan Research Foundation in Chennai, which does work on the conservation of biological diversity. Madhav Gadgil is a well-known ecologist in India. His interests range from board ecological issues such as developing community Biodiversity Registers and conserving sacred groves to studies on the behavior of mammals, birds and insects. His research interests include population biology, conservation biology, human ecology and ecological history and he has published over 215 research papers and 6 books and and the editor for the series ‘lifescapes of peninsular India’..

M. C. Mehta: Environmental lawyer. Initiated the Government to implement Environmental education in schools and colleges, struggles for protection of Taj Mahal and cleaning of Ganga water 

Anil Agarwal: a journalist who wrote the first report on the state of India’s Environment in 1982. He was the founder of CES, an active NGO that supports variousenvironmental issues.

Medha Patkar: known as one of rural India’s champions, has supported the cause of the downtrodden tribal people whose environment is being affected by the dams on the Narmada river. Sunderlal Bahuguna’s chipko movement has become an internationally well-known example of a highly successful conservation action program through the efforts of local people for guarding their forest resources. His fight to prevent the construction of the Tehri Dam in a fragile earthquake-prone setting is a battle that he continues to wage. The

Garhwal hills will always remember his dedication to the cause for which he has walked over 20 thousand kilometers.

DEFINITION,SCOPE AND IMPORTANCE OF ENVIRONMENTAL SCIENCE

INTRODUCTION

The science of Environment studies is a multi-disciplinary science because it comprises various branches of studies like chemistry, physics, medical science, life science, agriculture,public health, sanitary engineering etc. It is the science of physical phenomena in the environment. It studies of the sources,reactions,transport,effect and fate of physical biological species in the air, water and soil and the effect of from human activity upon these.Environment Explained Literary environment means the surround ing external conditions influencing development or growth of people, animal or plants; living or working conditions etc. This involves three questions:

1. What is Surrounded

The answer to this question is living objects in general and man in particular.

2. By what Surrounded

The physical attributes are the answer to this question, which become environment. In

fact, the concern of all education is the environment of man. However, man cannot exist or

be understood in isolation from the other forms of life and from plant life. Hence, environment

refers to the sum total of condition, which surround point in space and time. The scope of

the term Environment has been changing and widening by the passage of time. In the

primitive age, the environment consisted of only physical aspects of the planted earth' land,

air and water as biological communities. As the time passed on man extended his environment

through his social, economic and political functions.

3. Where Surrounded

The answer to this question. It is in nature that physical component of the plant earth,

viz land, air, water etc., support and affect life in the biosphere. 

Environmental Science :

1 Definition, Scope and Importance2 ENVIRONMENTAL SCIENCE

environment is the representative of physical components of the earth where in man is an important factor affecting the environment.

(i) Definitions of Environment : Some important definitions of environment are asunder:

1. Boring: A person’s environment consists of the sum total of the stimulation which he receives from his conception until his death.’It can be concluded from the above definition that Environment comprises various types of forces such as physical, intellectual, economic, political,cultural, social, moral and emotional. Environment is the sum total of all the external forces, influences and conditions, which affect the life,nature, behavior and the growth, development and maturation of livingorganisms.

2. Douglas and Holland: ‘The term environment is used to describe, in the aggregate, all the external forces, influences and conditions, which affect the life, nature, behavior and the growth, development and maturity of living organisms.’

(ii) Scope of Environment: The environment consists of four segments as under:

1. Atmosphere: The atmosphere implies the protective blanket of gases,surrounding the earth:

(a) It sustains life on the earth.

(b) It saves it from the hostile environment of outer space.

(c) It absorbs most of the cosmic rays from outer space and a major portion of theelectromagnetic radiation from the sun.

(d) It transmits only here ultraviolet, visible, near infrared radiation (300 to 2500

nm) and radio waves. (0.14 to 40 m) while filtering out tissue-damaging ultraviolate waves below about 300 nm.The atmosphere is composed of nitrogen and oxygen. Besides, argon, carbon dioxide,and trace gases. 

2. Hydrosphere: The Hydrosphere comprises all types of water resources oceans,seas, lakes, rivers, streams, reserviour, polar icecaps, glaciers, and ground water.

(i) Nature 97% of the earth’s water supply is in the oceans,

(ii) About 2% of the water resources is locked in the polar icecaps and glaciers.

(iii)Only about 1% is available as fresh surface water-rivers, lakes streams, and ground water fit to be used for human consumption and other uses.

3.Lithosphere is the outer mantle of the solid earth. It consists of minerals occurring in the earth’s crusts and the soil  e.g. minerals, organic matter, air and water.

4. Biosphere: Biosphere indicates the realm of living organisms and their interactions with environment, viz atmosphere, hydrosphere and lithosphere.

.ENVIRONMENTAL SCIENCE : DEFINITION, SCOPE AND IMPORTANCE 

Element of Environment

Environment is constituted by the interacting systems  of physical, biological and cultural elements inter-related in various ways, individually as well as collectively. These elements may be explained as under:

(1) Physical elements

Physical elements are as space, landforms, water bodies, climate soils, rocks and minerals. They determine the variable character of the human habitat, its opportunities as well as limitations.

(2) Biological elements

Biological elements such as plants, animals, microorganisms and men constitute the biosphere.

(3) Cultural elements

Cultural elements such as economic, social and political elements are essentially manmade features, which make cultural milieu.

ENVIRONMENT STUDIES: IMPORTANCE

Importance of Environment Studies: 

The environment studies enlighten us, about the importance of protection and conservation of our indiscriminate release of pollution into the environment. At present a great number of environment issues, have grown in size and complexity day by day, threatening the survival of mankind on earth. We study about these issues besides and effective suggestions in the Environment Studies. Environment studies have become significant for the following reasons:

1. Environment Issues Being of International Importance

It has been well recognised that environment issues like global warming and ozone depletion, acid rain, marine pollution and biodiversity are not merely national issues but are global issues and hence must be tackled with international efforts and cooperation.

2. Problems Cropped in The Wake of Development

Development, in its wake gave birth to Urbanization, Industrial Growth, Transportation Systems, Agriculture and Housing etc. However, it has become phased out in the developed world. The North, to cleanse their own environment has, fact fully, managed to move ‘dirty’ factories of South. When the West developed, it did so perhaps in ignorance of the environmental impact of its activities. Evidently such a path is neither practicable nor desirable, even if developing world follows that.

3. Explosively Increase in Pollution

World census reflects that one in every seven persons in this planted lives in India. Evidently with 16 per cent of the world's population and only 2.4 per cent of its land area,there is a heavy pressure on the natural resources including land. Agricultural experts have recognized soils health problems like deficiency of micro nutrients and organic matter, soil salinity and damage of soil structure.

4. Need for An Alternative Solution

It is essential, specially for developing countries to find alternative paths to an alternative goal. We need a goal as under:

(1) A goal, which ultimately is the true goal of development an environmentally sound and sustainable development.

(2) A goal common to all citizens of our earth.

(3) A goal distant from the developing world in the manner it is from the over-consuming wasteful societies of the “developed” world.

5. Need To Save Humanity From Extinction

It is incumbent upon us to save the humanity from exinction. Consequent to our activities constricting the environment and depleting the biosphere, in the name of development.

6. Need For Wise Planning of Development

Our survival and sustenance depend. Resources withdraw, processing and use of the product have all to by synchronized with the ecological cycles in any plan of development our actions should be planned ecologically for the sustenance of the environment and development.

7.  Misra’s Report

Misra (1991) recognized four basic principles of ecology, as under:

(i) Holism

(ii) Ecosystem

(iii) Succession

(iv) Conversation.

Holism has been considered as the real base of ecology. In hierarchical levels at which interacting units of ecology are discussed, are as under: Individual<population<community<ecosystem<biome<biosphere.

Misra (1991) has recognised four basic requirements of environmental management as

under:

(i) Impact of human activities on the environment,

(ii) Value system,

(iii) Plan and design for sustainable development,

(iv) Environment education.

Keeping in view the of goal of planning for environmentally sustainable development India contributed to the United Nations Conference on Environment and Development (UNCED), also referred to as “Earth Summit” held at Rio de Janciro, the Capital of Brazil, 3rd-14th June, 1992.

NEED FOR PUBLIC AWARENESS

It is essential to make the public aware of the formidable consequences of the Environmental Degradation, if not retorted and reformative measures undertaken, would result in the extinction of life. We are facing various environmental challenges. It is essential to get the country acquainted with these challenges so that their acts may be eco-friendly.

Some of these challenges are as under:

1. Growing Population

A population of over thousands of millions is growing at 2.11 per cent every year. Over17 million people are added each year. It puts considerable pressure on its natural resources and reduces the gains of development. Hence, the greatest challenge before us is to limit the population growth. Although population control does automatically lead to development, yet the development leads to a decrease in population growth rates. For this development of the women is essential.

2. Poverty

India has often been described a rich land with poor people. The poverty and environmental degradation have a nexus between them. The vast majority of our people are directly dependent on the nature resources of the country for their basic needs of food, fuel shelter and fodder. About 40% of our people are still below the poverty line. Environment degradation has adversely affected the poor who depend upon the resources of their immediate surroundings. Thus, the challenge of poverty  and the challenge environment degradation are two facets of the same challenge. The population growth is essentially a function of poverty. Because, to the very poor, every child is an earner and helper and global concerns have little relevance for him.

3. Agricultural Growth

The people must be acquainted with the methods to sustain and increase agricultural growth with damaging the environment. High yielding varities have caused soil salinity and damage to physical structure of soil.

4. Need to Ground water

It is essential of rationalizing the use of groundwater. Factors like community wastes, industrial effluents and chemical fertilizers and pesticides have polluted our surface waterand affected quality of the groundwater. It is essential to restore the water quality of our rivers and other water bodies as lakes is an important challenge. It so finding our suitable strategies for consecration of water, provision of safe drinking water and keeping water bodies clean which are difficult challenges is essential.

5. Development And Forests

Forests serve catchments for the rivers. With increasing demand of water, plan toharness the mighty river through large irrigation projects were made. Certainly, thesewould submerge forests; displace local people, damage flora and fauna. As such, the damson the river Narmada, Bhagirathi and elsewhere have become areas of political and scientific debate.Forests in India have been shrinking for several centuries owing to pressures of agriculture and other uses. Vast areas that were once green, stand today as wastelands.These areas are to be brought back under vegetative cover. The tribal communities inhabiting forests respects the trees and birds and animal that gives them sustenance. We must recognise the role of these people in restoring and conserving forests. The modern knowledge and skills of the forest deptt. should be integrated with the traditional knowledge and experienceof the local communities. The strategies for the joint management of forests should be evolved in a well planned way.

6. Degradation of Land

At present out of the total 329 mha of land, only 266 mha possess any potential for production. Of this, 143 mha is agricultural land nearly and 85 suffers from varying degreesof soil degradation. Of the remaining 123 mha, 40 are completely unproductive. The remaining83 mha is classified as forest land, of which over half is denuded to various degrees. Nearly406 million head of livestock have to be supported on 13 mha, or less than 4 per cent of the land classified as pasture land, most of which is overgrazed. Thus, our of 226 mha, about175 mha or 66 per cent is degraded to varying degrees. Water and wind erosion causes further degradation of almost 150 mha This degradation is to be avoided.

7. Reorientation of Institutions

The people should be roused to orient institutions, attitudes and infrastructures, to suit conditions and needs today. The change has to be brought in keeping in view India’s traditions for resources use managements and education etc. Change should be brought in education,in attitudes, in administrative procedures and in institutions. Because it affects way peopleview technology resources and development.

8. Reduction of Genetic Diversity

Proper measures to conserve genetic diversity need to be taken. At present most wild genetic stocks have been disappearing from nature. Wilding including the Asiatic Lion are facing problem of loss of genetic diversity. The protected areas network like sanctuaries,national  parks, biosphere reserves are isolating populations. So, they are decreasing changes of one group breeding with another. Remedial steps are to be taken to check decreasing genetic diversity.

9. Evil Consequences of Urbanisation

Nearly 27 per cent Indians live in urban areas. Urbanisation and industrialisation has given birth to a great number of environmental problem that need urgent attention. Over 30 percent of urban Indians live in slums. Out of India’s 3,245 towns and cities, only 21 have partial or full sewerage and treatment facilities. Hence, coping with rapid urbanization isa major challenge.

10. Air and water Population

Majority of our industrial plants are using outdated and population technologies and makeshift facilities devoid of any provision of treating their wastes. A great number of cities and industrial areas that have been identified as the worst in terms of air and water pollution. Acts are enforced in the country, but their implement is not so easy. The reason is their implementation needs great resources, technical expertise, political and social will.Again the people are to be made aware of these rules. Their support is indispensable to implement these rules.

VARIOUS TYPES OF ENVIRONMENT:

(a) Physical Environment,

(b) Social and Cultural Environment, and

(c) Psychological Environment.

These may be explained as under:

1. Physical Environment

Physical environment, refers to geographical climate and weather or physical conditions wherein and individual lives. The human races are greatly influenced by the climate. Some examples are as under:

(a) In the cold countries i.e. European countries the people are of white colour. Likewise,in Asian and African countries, that is, in hot countries people are of dark complexion.

(b) The physique of an individual depends on climate conditions as the individual tries to adjust in his physical environment.

(c) The human working efficiency also depends on the climatic conditions.

2. Social Environment

Social Environment includes an individual’s social, economic and political condition wherein he lives. The moral, cultural and emotional forces influence the life and nature of individual behavior. Society may be classified into two categories as under:

(i) An open society is very conductive for the individual developement.

(ii) A closed society is not very conductive for the development.

3. Psychological Environment

Although physical and social environment are common to the individual in a specific situation. Yet every individual has his own psychological environment, in which he lives.Kurt Lewin has used the term ‘life space’ for explaining psychological environment. The Psychological environment enables us to understand the personality of an  individual. Both the person and his goal form psychological environment.If a person is unable to overcome the barriers, he can either get frustrated or completed to change his goal for a new psychological environment. But adopting this mechanism, the individual is helped in his adjustment to the environment.

STRUCTURE OF ENVIRONMENT

Environment is both physical and biological. It includes both living and non-living components.

(i) Physical Environment

The Physical Environment is classified into three broad categories viz.

(i) Solid,

(ii) Liquid

(iii) Gas.

These represent the following spheres:

(i) The lithosphere (solid earth)

(ii) The hydrosphere (water component) and

(iii) The atmosphere

As such, the three basic of physical environment may be termed as under:

(i) Lithospheric Environment

(ii) Hydrospheric Environment

(iii) Atmospheric Environment

The scientists have classified them into smaller units based on different spatial scales,

e.g.

(i) Mountain Environment

(ii) Glacier Environment

(iii) Plateau Environment

(iv) Coastal Environment

(ii) Biological Environment

The biological of the environment consists of:

(i) Plants (flora)

(ii) Animals (fauna).

Thus, the biotic environment further be divided into floral environment and faunal environment. All the organisms work to form their social groups and organizations at several levels.  Thus, the social environment is formed. In this social environment the organisms work to derive matter from the physical environment for their sustenance and development.This process gives birth to economic environment. Man claims to be most skilled and civilizedof all the organisms. This is the reason why his social organisation is most systematic.  The

three aspects of man,  e.g. physical, social and economic, function in the biotic environmental under

(i) The Physical Man

The ‘Physical Man’ is one of the organisms populations or biological community. He is in need of basic elements of the physical environment like habitat (space), air, water and food. Besides, like other biological populations, he releases wastes into the ecosystem.

(ii) The Social Man

The ‘Social Man’ performs the following functions:

(a) Establishing social institutions,

(b) Forming social organisations

(c) Formulating laws, principles and policies,

(d) Taking steps to safeguard his existence, interest and social welfare.

(iii) The Economic Man

The economic man derives and utilises resources from the physical and biotic environment with his skills and technologies. The economic function makes the man an environment/geomorphic process as he transports matter and energy from one component of the ecosystem to the other. There may be any following two situations:

(a) His exploitative functions may be in harmony with the natural environment. Such,functions do not necessarily involve change in the working of the ecosystem.

(b) These functions may exceed the critical limit. Consequently, the equilibrium of the environment/ecosystem is disturbed and a great number of environment and ecological problems crop up. These are determental to man him besides to whole population of human species in a given ecosystem.

QUESTIONS

1. What is Environment? Discuss the scope of Environment.

2. Describe the importance of environment studies.

3. “The need for public awareness about environment is of vital importance.” Discuss.

4. Discuss the various types of environment.

Short Answer Type Questions

1. Define environments.

2. Discuss the scope of environment.

3. Write a note on the importance of environment studies.

4. Write a note on the need of public awareness about environment.

5. Write a note on physical environment.

6. Write a note on biological environment.

JL MODEL QUESTIONS

1. In plants, phosphorus is mainly used for (1)
1) Leaf growth 2) Flowering 3) Root growth 4) Leaf and root growth
2. Concave mirrors are used as shaving mirrors because they (2)
1) do not distort images 2) always produce real images
3) produce magnified images 4) never produce inverted images
3. In the human body, urea is produced in the (3)
1) Liver 2) Spleen 3) Kidneys 4) Pancreas
4. Sound travels faster in (3)
1) dry air than in water 2) wood than in iron
3) iron than in air 4) hydrogen than in water
5. In the human body, the pituitary gland is located in the (4)
1) Chest 2) Abdomen 3) Throat 4) Brain
6. Non-secretion of insulin causes (1)
1) Diabetes 2) Malaria 3) Ulcer 4) Tuberculosis
7. The unmanned aircraft developed in India is called (2)
1) Lakshya 2) Nishant 3) Trishul 4) Hansa
8. Photoelectric cells are used to convert (3)
1) Light energy into sound energy 2) Light energy into heat energy
3) Light energy into electrical energy 4) Electrical energy into light energy
9. India's first exclusive meterological satellite launched recently took the Earth's
image in full frame mode. What is the name of the satellite? (4)
1) INSAT-IC 2) INSAT-2B 3) INSAT-1A 4) METSAT
10. Which among the following is the richest source of protien? (4)
1) Black gram 2) Bengal gram 3) Pea 4) Soyabean
11. Which kind of light waves are used in the remote control of Television? (2)
1) Visible light 2) Infra-red 3) X-rays 4) r- rays
12. What is the name of the world's first cloned human baby? (1)
1) The Eve 2) Dolly 3) The Shrine 4) Abbey
13. Genome Mapping is related to (2)
1) Blood grouping 2) Mapping of genes
3) Mapping of nerve centres 4) Mapping of the brain
14. The technology which allows the user to access the Internet through the mobile
phone without using a modem or computer, is (4)
1) PGRS 2) RPGS 3) SPGR 4) GRPS
15. Of the following diseases, which one is related to the spinal column of man? (3)
1) Hypothermia 2) Cataract 3) Cervical spondylosis 4) Hernia
16. Which of the following human organs is least suceptible to harmful radiation?
1) Eyes 2) Heart 3) Brain 4) Lungs ()
17. The fuel efficiency of dry cattle dung in comparison to bio-gas is (2)
1) One- fourth 2) One- fifth 3) One-Sixth 4) One-eighth
GENERAL STUDIES
A.P.P.S.C Jr. LECTUTERS - 2003 18. Which of the following is named 'Gajraj'? (1)
1) MIG-27 2) Jaguar 3) Mirage 2000 4) IL-76
19. The missile 'Agni'-has a range of (3)
1) 1000 km 2) 700 km 3) 2000 km 4) 200 km
20. The largest Telecome operator in India is (1)
1) BSNL 2) MTNL 3) Tata Indicom 4) Reliance Info.comm
21. Which of the following cities has India's first "Techno Park"? ()
1) Gurgaon 2) Pune 3) Bangalore 4) Thiruvananthapuram
22. The National Institute of Oceanography is located at (4)
1) Cochin 2) Mumbai 3) Chennai 4) Goa
23. Which of the following is a mixture? (4)
1) Lime 2) Table salt 3) Sugar 4) Sea water
24. Where does genetic mutation occur? (1)
1) In DNA 2) In RNA 3) In chromosomes 4) In ribosomes
25. An element is best characterised by its (1)
1) Electronic configuration 2) Atomic number 3) Atomic weight 4) Atomic volume
26. The Supreme Court has allowed the construction of the Sardar Sarovar Dam up to a height of
1) 88 metres 2) 90 metres 3) 100 metres 4) 120 metres (2)
27. The Central Rice Institute of India is located in (2)
1) Kolkata 2) Cuttak 3) Bangalore 4) Guwahati
28. The Rana Pratap Sagar Power Plant (Rajasthan) is associated with (1)
1) Nuclear power 2) Solar power 3) Hydro-electricity 4) Gas-based electricity
29. Which of the following States is the leading producer of wollen textiles? (2)
1) Jammu & Kashmir 2) Punjab 3) Rajasthan 4) Himachal Pradesh
30. Which of the following Oil Corporations in the Public Sector has proposed
setting up a new oil refinery at Bina in M.P.? (1)
1) Indian Oil Corporation 2) Bharat Petroleum Corporation
3) Hindustan Petroleum Corporation 4) Indo-Burma Petroleum Corporation
31. At the mouth of which river is India's largest estuary located (2)
1) Hooghly 2) Bhagirathi 3) Godavari 4) Krishna
32. The most extensive soil cover of India comprises is its (2)
1) Red Soil 2) Black soil 3) Alluvial soil 4) Marshy soil
33. The most sensitive indicator of the health of a community is its (3)
1) Birth Rate 2) Infant Mortality Rate 3) Death Rate 4) Maternal Mortality Rate
34. In India, banks were nationalised for the first time in the year (2)
1) 1950 2) 1960 3) 1969 1979
35. Similipal in Orissa state is well known for its (2)
1) Stone -carved temple complex 2) Wild-life sanctuary
3) Virgin beach 4) Hydro-electric power project
36. Where are tropical evergreen forests found in India? (1)
1) Kerala 2) Andhra Pradesh 3) Madhya Pradesh 4) Orissa
37. Certain economists opine that Indian economy has reached the "Take off" stage. It means
1) The economy is about to collapse 2) The economy is stagnant (3)
3) The beginning of steady growth 4) The removal of all controls