Environmental Studies - Quick Guide

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Environmental Studies - Environment

The word ‘environment’ is derived from the old French word ‘environer’ – which means to ‘surround, enclose, and encircle’. Environment refers to an aggregate of conditions or surroundings in which living beings such as humans, animals, and plants live or survive and non-living things exist.

All living beings including man and their environment are mutually reactive, affecting each other in a number of ways. It is generally equated with nature wherein physical components of the planet earth such as earth, air, water, etc. support and affect life in the biosphere.

Environment represents the physical components of the earth, wherein man is an important factor affecting the environment.

Environment comprises interacting systems of physical, biological, and cultural elements, which are interlinked individually as well as collectively in various ways.

Constituents of Environment

Physical elements constitute space, landforms, water-bodies, climate, soils, rocks, and minerals. These elements determine the variable character of human habitat, and also its opportunities and limitations.

Biological elements include plants, animals, micro-organisms, and man.

Cultural elements include economic, social and political conditions which are largely man-made features.

Types of Environment

Since environment is a combination of physical and biological factors, it contains both living or biotic and non-living or abiotic components. On the basis of this basic structure, environment can be divided into physical or abiotic and living or biotic environment.

Physical or Abiotic Environment

Physical environment is made up of the following states - solid, liquid, and gas. These three elements signify lithosphere, hydrosphere, and atmosphere respectively. On the basis of spatial distribution, smaller units are termed as coastal environment, plateau environment, mountain environment, lake environment, river environment, maritime environment, etc.

Living or Biotic Environment

Biotic environment consists of plants (flora) and animals (fauna) including human beings as a significant factor. Thus, biotic environment can be of two types such as floral environment and faunal environment.

Apart from the above, there are social, cultural, and psychological environment.

Social and Cultural Environment

This type of environment includes the varied aspects of socio-cultural interactions along with its outcomes such as beliefs, attitudes, stereotypes etc. The tangible and intangible aspects of environment are included in it.

Psychological Environment

Psychological environment deals with the perception and experiences related to any environmental setting. Some environment may be stimulating and exciting for us, while others may be dull and boring. Psychological environment is more often used in the organizational context.

Man-Environment Relationship

Man and environment relationship is as old as the evolution of mankind. Since the evolution of man, the physical elements of the planet earth, such as terrain, soil, water, climate, flora and fauna formed man’s environment. During that time man was a typically a ‘physical man’ because of his limited wants, requirements, and total dependence on nature.

With the growth in social and economic activities, advancement in technologies, man expanded his own environment through design and skill to have provisions for improved and better food, shelter, access, and comfort or luxuries. Man’s ability to survive in a variety of ecosystem and his unique ability to adapt to a great variety of external conditions make man-environment relationship quite a fascinating area of study.

The environment in which man survives and to which he adapts himself and which he influences include physical, socio-cultural, and biological aspects. Man and environment has never been static and a great many factors are responsible for the shifts in man environment relationship.

Approaches to Man-Environment Relationship

The man and environment relationship can be studied under the following approaches.

Determinism − Friedrich Ratzel, the German geographer, was responsible for the development of the concepts of determinism, which was further expanded by Ellsworth Huntington.

This approach is based on the concept of ‘nature controls man’ or ‘earth made man’. According to this approach, man is largely influenced by nature. In fact, the determinism states that man is subordinate to natural environment because all aspects of human life such as physical (health and well-being), social, economic, political, ethical, aesthetic, etc. not only depend on but are dominantly controlled by the physical environment.

World famous biologist, Charles Darwin, in 1859 laid the foundation stone of the concept of environment influences on man and other organism.

Possibilism − Lucien Febvre, the French historian, founded the concept of Possibilism. Possibilism approach in the study of man-environment relationship is an offshoot of the criticism of environmental determinism and the impact of science and technology on such a relationship.

Possibilism indicates that the physical environment is passive and man is the active agent at liberty to choose between wide ranges of environmental possibilities. According to it, the pattern of human activity is the result of the initiative and mobility of man operating within the natural framework. Nowadays, the role of natural elements in conditioning, though not controlling human activities, is often lost sight of.

Possibilists were largely aware of the limitations of freedom of man to dictate terms to environment. It was agreed upon by the possibilists that man lacks the abilities to fully tame the nature and is not always victorious over it. As result of the above, some geographers vouched for ‘cooperation with nature’ or ‘mutual interaction’ between man and environment.

Ecological Approach − This approach is based upon the basic principle of ecology, which is the study of mutual interaction between organisms and physical environment on the one hand, and the interaction among the organism on the other in a given ecosystem. This approach describes man as an integral part of nature or environment. Man, being most skilled and intelligent, has a unique role to play in maintaining a natural environment as healthy and productive as it should be.

This approach emphasizes on wise and restrained use of natural resources, application of appropriate environmental management programs, policies and strategies keeping in view certain basic principles of ecology so that already depleted natural resources are replenished, and health and productivity of the nature is restored.

What is Environmental Studies?

Environmental studies refer to an extensive and systematic study of nature/environment and of its physical, biological, social, and cultural factors, and the nature and characteristics of relationship between man and environment. How far man influences nature and to what extent nature delivers its bounties constitute another objective of environmental studies.

It is an interdisciplinary study as subjects like ecology, biochemistry, toxicology, geography, geology, meteorology, sociology, etc. are dealt with under environmental studies.

The Need for Environmental Studies

Nature or environment sustains life. As a conscious and rational being, man needs to know the importance of environment and help keep the environment as healthy and productive as it can be. It is the environment that has made this beautiful world possible for him. Hence, there is an ever demanding need for environmental studies.

The natural environment that mankind had before the onset of industrialization, urbanization, and exponential growth in population was expectedly healthy and resilient. Nature was able to replenish the loss of its resources, which was very limited.

After the onset of modern civilization, the overall health and efficiency of natural environment started deteriorating gradually and went on to such an extent that nature has virtually lost its natural ability to replenish the loss of resources caused by man.

Environmentalists, geographers, and biologists the world over are constantly endeavoring for a sustainable solution to restore a sustainable environment.

There is a need for focus on environmental management, laws governing environment protection, pollution and recycling of non-bio-degradable material, etc. There is also a need for careful and cautious use of natural resources in the present time to establish sustainability in every aspect of nature.

There is a need to clarify modern environmental concepts such as how to conserve biodiversity and maintain an ecological balance.

Environmental studies help us understand the importance of our environment and teaches us to use natural resources more efficiently and embrace a sustainable way of living. It enables us to know the behavior of organisms under natural conditions and the interrelationship between organisms in population and communities.

Environmental Studies - Ecosystem

The interaction and interrelationship between the living community (plants, animals, and organisms) in relation to each other and the non-living community (soil, air, and water) is referred to as an ecosystem. Thus, an ecosystem is a structural and functional unit of biosphere. It is made up of living and non-living beings and their physical environment.

In other words, a natural ecosystem is defined as a network of interactions among the organisms and between organisms and their environment. Nutrient cycles and energy flows keep these living and non-living components connected in an ecosystem.

Ecosystem - Scope and Importance

Ecosystem is a part of natural environment consisting of a community of living beings and the physical environment both constantly interchanging materials and energy between them. It is the sum total of the environment or a part of nature.

The environment consists of four segments as follows −

• Atmosphere − The atmosphere refers to the protective blanket of gases, surrounding the earth. It sustains life on the earth. It saves the Earth from the hostile environment of the outer space. The atmosphere composed of nitrogen and oxygen in large quantity along with small percentage of other gases such as argon, carbon dioxide, and trace gases (the gases which makes up less than 1 percent by volume of the atmosphere.

• Hydrosphere − Hydrosphere comprises all water resources such as ocean, seas, lakes, rivers, reservoirs, icecaps, glaciers, and ground water.

• Lithosphere − It is the outer mantle of the solid earth. It contains minerals occurring in the earth’s crust and the soil.

• Biosphere − It constitutes the realm of living organisms and their interactions with the environment (atmosphere, hydrosphere, and lithosphere).

The study of ecosystem or environmental studies has been seen to be multidisciplinary in nature, hence, it is considered to be a subject with great scope. It is no more confined only to the issues of sanitation and health; rather, it is now concerned with pollution control, biodiversity conservation, waste management and conservation of natural resources.

Classification of Ecosystem

The ecosystems are classified into many types and are classified based on a number of factors. We will discuss major types of ecosystems and will try and understand on what basis these classifications are done. It is also essential to know the different factors which differentiate the ecosystems from one another.

Ecosystems can generally be classified into two classes such as natural and artificial. Artificial ecosystems are natural regions affected by man’s interferences. They are artificial lakes, reservoirs, townships, and cities. Natural ecosystems are basically classified into two major types. They are aquatic ecosystem and terrestrial ecosystem.

Types of Natural Ecosystem

An ecosystem is a self-contained unit of living things and their non-living environment. The following chart shows the types of Natural Ecosystem −

Biotic (Living Components)

Biotic components in ecosystems include organisms such as plants, animals, and microorganisms. The biotic components of ecosystem comprise −

• Producers or Autotrophs
• Consumers or Heterotrophs
• Decomposers or Detritus

Abiotic (Non-living Components)

Abiotic components consist of climate or factors of climate such as temperature, light, humidity, precipitation, gases, wind, water, soil, salinity, substratum, mineral, topography, and habitat. The flow of energy and the cycling of water and nutrients are critical to each ecosystem on the earth. Non-living components set the stage for ecosystem operation.

Aquatic Ecosystem

An ecosystem which is located in a body of water is known as an aquatic ecosystem. The nature and characteristics of the communities of living or biotic organisms and non-living or abiotic factors which interact with and interrelate to one another are determined by the aquatic surroundings of their environment they are dependent upon.

Aquatic ecosystem can be broadly classified into Marine Ecosystem and Freshwater Ecosystem.

Marine Ecosystem

These ecosystems are the biggest of all ecosystems as all oceans and their parts are included in them. They contain salt marshes, intertidal zones, estuaries, lagoons, mangroves, coral reefs, the deep sea, and the sea floor.

Marine ecosystem has a unique flora and fauna, and supports a vast kingdom of species. These ecosystems are essential for the overall health of both marine and terrestrial environments.

Salt marshes, seagrass meadows, and mangrove forests are among the most productive ecosystem. Coral reef provides food and shelter to the highest number of marine inhabitants in the world. Marine ecosystem has a large biodiversity.

Freshwater Ecosystem

Freshwater ecosystem includes lakes, rivers, streams, and ponds. Lakes are large bodies of freshwater surrounded by land.

Plants and algae are important to freshwater ecosystem because they provide oxygen through photosynthesis and food for animals in this ecosystem. Estuaries house plant life with the unique adaptation of being able to survive in fresh and salty environments. Mangroves and pickle weed are examples of estuarine plants.

Many animals live in freshwater ecosystem. Freshwater ecosystem is very important for people as they provide them water for drinking, energy and transportation, recreation, etc.

Terrestrial Ecosystem

Terrestrial ecosystems are those ecosystems that exist on land. Water may be present in a terrestrial ecosystem but these ecosystems are primarily situated on land. These ecosystems are of different types such as forest ecosystem, desert ecosystem, grassland and mountain ecosystems.

Terrestrial ecosystems are distinguished from aquatic ecosystems by the lower availability of water and the consequent importance of water as a limiting factor. These are characterized by greater temperature fluctuations on both diurnal and seasonal basis, than in aquatic ecosystems in similar climates.

Availability of light is greater in terrestrial ecosystems than in aquatic ecosystems because the atmosphere is more transparent on land than in water. Differences in temperature and light in terrestrial ecosystems reflect a completely different flora and fauna.

Functions of Ecosystem

The functional attributes of the ecosystem keep the components running together. Ecosystem functions are natural processes or exchange of energy that take place in various plant and animal communities of different biomes of the world.

For instance, green leaves prepare food and roots absorb nutrients from the soil, herbivores feed on the leaves and the roots and in turn serve as food for the carnivores.

Decomposers execute the functions of breaking down complex organic materials into simple inorganic products, which are used by the producers.

Fundamentally, ecosystem functions are exchange of energy and nutrients in the food chain. These exchanges sustain plant and animal life on the planet as well as the decomposition of organic matter and the production of biomass.

All these functions of the ecosystem take place through delicately balanced and controlled processes.

Food Chain

The order of living organisms in a community in which one organism consumes other and is itself consumed by another organism to transfer energy is called a food chain. Food chain is also defined as “a chain of organisms, existing in any natural community, through which energy is transferred”.

Every living being irrespective of their size and habitat, from the tiniest algae to giant blue whales, need food to survive. Food chain is structured differently for different species in different ecosystems. Each food chain is the vital pathway for energy and nutrients to follow through the ecosystem.

Food chains were first introduced by the African-Arab scientist and philosopher Al-Jahiz in the 9^th century and later popularized in a book published in 1927 by Charles Elton.

A food chain starts with a producer such as plants. Producers form the basis of the food chains. Then there are consumers of many orders. Consumers are organisms that eat other organisms. All organisms in a food chain, except the first organism, are consumers.

Plants are called producers because they produce their own food through photosynthesis. Animals are called consumers because they depend on plants or other animals for food to get energy they need.

In a certain food chain, each organism gets energy from the one at the level below. In a food chain, there is reliable energy transfer through each stage. All the energy at one stage of the chain is not absorbed by the organism at the next stage.

Trophic Levels in a Food Chain

Trophic levels are different stages of feeding position in a food chain such as primary producers and consumers of different types.

Organisms in a food chain are categorized under different groups called trophic levels. They are as follows.

Producers (First Trophic Level) − Producers otherwise called autotrophs prepare their food by themselves. They form the first level of every food chain. Plants and one-celled organisms, some types of bacteria, algae, etc. come under the category of Autotrophs. Virtually, almost all autotrophs use a process called photosynthesis to prepare food.

Consumers − At the second trophic level, there are consumers who depend upon others for food.

• Primary Consumers (Second Trophic Level) − Primary consumers eat the producers. They are called herbivores. Deer, turtle, and many types of birds are herbivores.

• Secondary Consumers (Third Trophic Level) − Secondary consumers based at the third trophic level eat plants and herbivores. They are both carnivores (meateaters) and omnivores (animals that eat both animals and plants). In a desert ecosystem, a secondary consumer may be a snake that eats a mouse. Secondary consumers may eat animals bigger than they are. Some lions, for example, kill and eat buffalo. The buffalo weighs twice as much as the lions do.

• Tertiary Consumers (Fourth Trophic Level) − Tertiary consumers are animals eating other carnivores. The secretary bird in Africa and the King Cobra specialize in killing and eating snakes but all snakes are carnivores. The leopard seal eats mostly other carnivores - mainly other seals, squids, and penguins, all of which are carnivores.

Decomposers − Decomposers which don’t always appear in the pictorial presentation of the food chain, play an important part in completing the food chain. These organisms break down dead organic material and wastes. Fungi and bacteria are the key decomposers in many ecosystems; they use the chemical energy in dead matter and wastes to fuel their metabolic processes. Other decomposers are detritivores—detritus eaters or debris eaters.

Understanding the food chain helps us know the feeding interrelationship and interaction between an organism and the ecosystem. It also enables us to know the mechanism of energy flow in an ecosystem.

Food Web

The word ‘web’ means network. Food web can be defined as ‘a network of interconnected food chains so as to form a number of feeding relationships amongst different organism of a biotic community.

A food chain cannot stand isolated in an ecosystem. The same food resource may be a part of more than one chain. This is possible when the resource is at the lower tropic level.

A food web comprises all the food chains in a single ecosystem. It is essential to know that each living thing in an ecosystem is a part of multiple food chains.

A single food chain is the single possible path that energy and nutrients may make while passing through the ecosystem. All the interconnected and overlapping food chains in an ecosystem make up a food web.

Food webs are significant tools in understanding that plants are the foundation of all ecosystem and food chains, sustaining life by providing nourishment and oxygen needed for survival and reproduction. The food web provides stability to the ecosystem.

The tertiary consumers are eaten by quaternary consumers. For example, a hawk that eats owls. Each food chain ends with a top predator and animal with no natural enemies (such as an alligator, hawk, or polar bear).

Environmental Studies - Ecological Pyramid

Ecological Pyramid refers to a graphical (pyramidal) representation to show the number of organisms, biomass, and productivity at each trophic level. It is also known as Energy Pyramid. There are three types of pyramids. They are as follows −

Pyramid of Biomass

As the name suggests, the Biomass Pyramids show the amount of biomass (living or organic matter present in an organism) present per unit area at each trophic level. It is drawn with the producers at the base and the top carnivores at the tip.

Pyramid of biomass is generally ascertained by gathering all organisms occupying each trophic level separately and measuring their dry weight. Each trophic level has a certain mass of living material at a particular time called standing crop, which is measured as the mass of living organisms (biomass) or the number in a unit area.

Upright Pyramid of Biomass

Ecosystems found on land mostly have pyramids of biomass with large base of primary producers with smaller trophic level perched on top, hence the upright pyramid of biomass.

The biomass of autotrophs or producers is at the maximum. The biomass of next trophic level, i.e. primary consumers is less than the producers. Similarly, the other consumers such as secondary and tertiary consumers are comparatively less than its lower level respectively. The top of the pyramid has very less amount of biomass.

Inverted Pyramid of Biomass

On the other hand, a reverse pyramidal structure is found in most aquatic ecosystems. Here, the pyramid of biomass may assume an inverted pattern. However, pyramid of numbers for aquatic ecosystem is upright.

In a water body, the producers are tiny phytoplankton that grow and reproduce rapidly. In this condition, the pyramid of biomass has a small base, with the producer biomass at the base providing support to consumer biomass of large weight. Hence, it assumes an inverted shape.

Pyramid of Numbers

It is the graphic representation of number of individuals per unit area of various trophic levels. Large number of producers tend to form the base whereas lower number of top predators or carnivores occupy the tip. The shape of the pyramid of numbers varies from ecosystem to ecosystem.

For example, in an aquatic ecosystem or grassland areas, autotrophs or producers are present in large number per unit area. The producers support a lesser number of herbivores, which in turn supports fewer carnivores.

Upright Pyramid of Numbers

In upright pyramid of numbers, the number of individuals decreases from the lower level to the higher level. This type of pyramid is usually found in the grassland ecosystem and the pond ecosystem. The grass in a grassland ecosystem occupies the lowest trophic level because of its abundance.

Next comes the primary producers – the herbivores (for example – grasshopper). The number of grasshoppers is quite less than that of grass. Then, there are the primary carnivores, for example, the rat whose number is far less than the grasshoppers. The next trophic level is the secondary consumers such as the snakes who feed on the rats. Then, there are the top carnivores such as the hawks who eat snakes and whose number is less than the snakes.

The number of species decreases towards the higher levels in this pyramidal structure.

Inverted Pyramid of Numbers

Here, the number of individuals increase from the lower level to the higher trophic level. For example, the tree ecosystem.

Pyramid of Energy

It is a graphical structure representing the flow of energy through each trophic level of a food chain over a fixed part of the natural environment. An energy pyramid represents the amount of energy at each trophic level and loss of energy at each is transferred to another trophic level.

Energy pyramid, sometimes called trophic pyramid or ecological pyramid, is useful in quantifying the energy transfer from one organism to another along the food chain.

Energy decreases as one moves through the trophic levels from the bottom to the top of the pyramid. Thus, the energy pyramid is always upward.

Energy Flow in Ecosystem

Energy moves life. The cycle of energy is based on the flow of energy through different trophic levels in an ecosystem. Our ecosystem is maintained by the cycling energy and nutrients obtained from different external sources. At the first trophic level, primary producers use solar energy to produce organic material through photosynthesis.

The herbivores at the second trophic level, use the plants as food which gives them energy. A large part of this energy is used up for the metabolic functions of these animals such as breathing, digesting food, supporting growth of tissues, maintaining blood circulation and body temperature.

The carnivores at the next trophic level, feed on the herbivores and derive energy for their sustenance and growth. If large predators are present, they represent still higher trophic level and they feed on carnivores to get energy. Thus, the different plants and animal species are linked to one another through food chains.

Decomposers which include bacteria, fungi, molds, worms, and insects break down wastes and dead organisms, and return the nutrients to the soil, which is then taken up by the producers. Energy is not recycled during decomposition, but it is released.

Biogeochemical Cycles

All elements in the earth are recycled time and again. The major elements such as oxygen, carbon, nitrogen, phosphorous, and sulphur are essential ingredients that make up organisms.

Biogeochemical cycles refer to the flow of such chemical elements and compounds between organisms and the physical environment. Chemicals taken in by organisms are passed through the food chain and come back to the soil, air, and water through mechanisms such as respiration, excretion, and decomposition.

As an element moves through this cycle, it often forms compounds with other elements as a result of metabolic processes in living tissues and of natural reactions in the atmosphere, hydrosphere, or lithosphere.

Such cyclic exchange of material between the living organisms and their non-living environment is called Biogeochemical Cycle.

Following are some important biogeochemical cycles −

• Carbon Cycle
• Nitrogen Cycle
• Water Cycle
• Oxygen Cycle
• Phosphorus Cycle
• Sulphur Cycle

Carbon Cycle

Carbon enters into the living world in the form of carbon dioxide through the process of photosynthesis as carbohydrates. These organic compounds (food) are then passed from the producers to the consumers (herbivores & carnivores). This carbon is finally returned to the surrounding medium by the process of respiration or decomposition of plants and animals by the decomposers. Carbon is also recycled during the burning of fossil fuels.

Nitrogen Cycle

Nitrogen is present in the atmosphere in an elemental form and as such it cannot be utilized by living organisms. This elemental form of nitrogen is converted into combined state with elements such as H, C, O by certain bacteria, so that it can be readily used by the plants.

Nitrogen is being continuously expelled into the air by the action of microorganisms such as denitrifying bacteria and finally returned to the cycle through the action of lightening and electrification.

Water Cycle

The evaporation of water from ocean, rivers, lakes, and transpiring plants takes water in the form of vapors to the atmosphere. This vaporized water subsequently cools and condenses to form cloud and water. This cooled water vapor ultimately returns to the earth as rain and snow, completing the cycle.

Environmental Studies - Natural Resources

Resources obtained from nature, i.e. from the earth are called natural resources. These resources occur naturally, and humans cannot make them. The raw materials used in artificial or man-made resources are natural resources.

Classification of Natural Resources

Classification of natural resources can be done in several ways based on their origin, level of development and uses, stock or deposits, and their distribution.

On the basis of their origin, natural resources can be classified into living or biotic and non-living or abiotic resources.

Living or Biotic Resources

If natural resources come from living things or organic materials, they are termed as living or biotic resources. Biotic resources include plants, animals and fossil fuels. Fossil fuels such as coal, oil and natural gas are classified as biotic resources as they are formed from the decay of organic matter over millions of years.

Non-living or Abiotic Resources

On the other hand, if the resources are derived from nonliving or inorganic materials, they are termed as abiotic resources. For instance, air, sunlight, and water are abiotic natural resources. Minerals are also considered abiotic.

On the basis of deposit or stock, natural resources can be classified as renewable and non-renewable.

Renewable Natural Resources

Resources that can be used without any risk of its ending up are called renewable resources. They exist in unlimited quantity. Sun, water, wind, biomass, tides, geothermal energy, etc. are renewable resources. These are infinite sources of energy.

Non-renewable Natural Resources

Those natural resources, on the other hand, that cannot be replenished after their depletion is called non-renewable resources. Most fossil fuels, such as coal, petroleum and natural gas are considered nonrenewable resources. Nonrenewable resources take billions of years for their formation, hence, their cautious and economic use is the only option left for mankind.

On the basis of development of resources, natural resources can be classified as actual and potential resources.

Actual Resources

An actual resource is one which is used in current times. We know their approximate quantity, for example: coal deposit.

Potential Resources

A potential resource is one whose utility is not known at present or is not used despite having the same. Instead, it may be useful at some time in future. In other words, such resources have the potential to have utility, although it does not have any today. For example, uranium deposit in Ladakh in India.

Environmental Studies - Water Resources

Water is a vital elixir for all living beings. Although it is a renewable resource, scarcity of quality water is felt in many parts of the world. We need water to grow food, keep clean, generate electricity, control fire, and last but not the least, we need it to stay alive.

World Ocean water covers about 75 percent of the surface of the earth. Therefore, the earth is called the water planet. Ocean water is saline and not fit for human consumption. Fresh water is just about 2.7 percent of the total water. Global warming and perpetuating water pollution have made a considerable part of available freshwater unfit for human consumption. As a result, water is very scarce.

Steps need to be taken to conserve water. Water is renewable, but its overuse and pollution make it unfit for use. Sewage, industrial use, chemicals, etc. pollute water with nitrates, metals, and pesticides.

Use of Water Resources

Water resources are used for agricultural, industrial, domestic, recreational, and environmental activities. Majority of the uses require fresh water.

However, about 97 percent of water found on the earth is salt water and only three percent is fresh water. A little over two-thirds of the available fresh water is frozen in glaciers and polar ice caps. The remaining freshwater is found mainly as groundwater and a negligible portion of it is present on the ground or in the air.

Following is a brief account of how water is used in different sectors.

Agricultural Use

Agriculture accounts for 69 percent of all water consumption basically in agricultural economies like India. Agriculture, therefore, is the largest consumer of the Earth’s available freshwater.

By 2050, the global water demand of agriculture is estimated to increase by a further 19% due to irrigational needs. Expanding irrigation needs are likely to put undue pressure on water storage. It is still inconclusive whether further expansion of irrigation, as well as additional water withdrawals from rivers and groundwater, will be possible in future.

Industrial Use

Water is the lifeblood of the industry. It is used as a raw material coolant, a solvent, a transport agent, and as a source of energy. Manufacturing industries account for a considerable share in the total industrial water consumption. Besides, paper and allied products, chemicals and primary metals are major industrial users of water.

Worldwide, the industry accounts for 19 percent of total consumption. In industrialized countries, however, industries use more than half of the water available for human use.

Domestic Use

It includes drinking, cleaning, personal hygiene, garden care, cooking, washing of clothes, dishes, vehicles, etc. Since the end of World War II there has been a trend of people moving out of the countryside to the ever-expanding cities. This trend has important implications on our water resources.

Government and communities have had to start building large water-supply systems to deliver water to new populations and industries. Of all water consumption in the world, domestic use accounts for about 12 percent.

Use for Hydropower Generation

Electricity produced from water is hydropower. Hydropower is the leading renewable source of electricity in the world. It accounts for about 16 percent of total electricity generation globally. There are many opportunities for hydropower development throughout the world.

Today, the leading hydropower generating countries are China, the US, Brazil, Canada, India, and Russia.

Use for Navigation and Recreation

Navigable waterways are defined as watercourses that have been or may be used for transport of interstate or foreign commerce. Agricultural and commercial goods are moved on water on a large scale in a number of regions in the world.

Water is also used for recreational purposes such as boating, swimming, and sporting activities. These uses affect the quality of water and pollute it. Highest priority should be given to public health and drinking water quality while permitting such activities in reservoirs, lakes, and rivers.

Overutilization of Surface and Ground Water

Water scarcity has become a burning global issue. The UN has held several conventions on water in recent decades. Continuous overutilization of surface and ground water has led to virtual water scarcity in the world today.

The depleting sources for high growth in human population over the centuries and increased man-induced water pollution across the world have created unforeseen water scarcity around the globe. As a result, there has been continuous overutilization of the existing water sources due to mammoth growth in world population.

Groundwater is the major source of water in many parts of the world. However, there has been continuous depletion of this source due to its overexploitation by rising human population and the rapid rise in industrialization and urbanization in modern times.

Consequences of Overutilization

Water scarcity now becomes an important topic in international diplomacy. From village to the United Nations, water scarcity is a widely-discussed topic in decision making.

Nearly three billion people in the world suffer from water scarcity. International, intrastate and regional rivalries on water are not new to world. The ongoing Jordan River conflict, Nile River conflict, and Aral Sea conflict are cases in point. The intra-state issues such as Cauvery Water dispute in South India, 2000 Cochabamba protests in Bolivia is still a simmering cauldron causing periodic tension at the national and regional levels.

According to World Health Organization (WHO) sources, a combination of rising global population, economic growth and climate change means that by 2050 five billion (52%) of the world’s projected 9.7 billion people will live in areas where fresh water supply is under pressure. Researchers expect about 1 billion more people to be living in areas where water demand exceeds surface-water supply.

Climate Change

Scientists, environmentalists, and biologists worldwide are now alarmed that climate change can have an impact on the drainage pattern and hydrological cycle on the earth thereby severely affecting the surface and groundwater availability.

Climate change is believed to rise the global temperature at an increasing pace. Temperature increase affects the hydrological cycle by directly increasing evaporation of available surface water and vegetation transpiration.

As a result, precipitation amount, timing and intensity rates are largely affected. It impacts the flux and storage of water in surface and subsurface reservoirs.

Floods & Draughts

Floods and droughts are two well-known natural hazards in the world. The former is due to excess in water flow and the latter is due to scarcity of water.

The amount of rainfall received by an area varies from one place to another depending on the location of the place. In some places it rains almost throughout the year whereas in other places it might rain for only few days. India records most of its rainfall in the monsoon season.

Heavy rains lead to rise in the water level of rivers, seas, and oceans. Water gets accumulated in the coastal areas, which results in floods. Floods bring in extensive damage to crops, domestic animals, property and human life. During floods, many animals get carried away by the force of water and eventually die.

On the other hand, droughts set in when a particular region goes without rain for a long period of time. In the meantime, the soil will continuously lose groundwater by the process of evaporation and transpiration. Since this water is not brought back to earth in the form of rains, the soil becomes very dry.

The level of water in the ponds and rivers goes down and in some cases water bodies get dried up completely. Ground water becomes scarce and this leads to droughts. In drought conditions, it is very difficult to get food and fodder for the survival. Life gets difficult and many animals perish in such conditions.

Frequent floods and droughts are mostly due to climate change and global warming. Various environmental organizations world over are of the view that climate change is a long-term change in weather patterns, either in average weather conditions or in the distribution of extreme weather events.

Environmental Studies - Mineral Resources

Minerals are naturally occurring elements or compounds that have been formed through slow inorganic processes. Modern civilization is based on the use and exploitation of mineral resources. Minerals can be metallic and non-metallic.

Minerals are not evenly distributed in the Earth. Some countries are rich in mineral deposits whereas others are devoid of it.

Use of mineral resources is an integral part and one of the key premises of development worldwide. With rapid increase in population and a more rapid increase in society’s development needs, the requirements for minerals have grown and diversified manifold.

Extraction of minerals is carried out through mining. Minerals are extracted from beneath the surface, processed, and used for different purposes.

Mineral resources, however, are exhaustible and finite, which means excessive use may affect their availability in the future.

Exploitation of Mineral Resources

Exploitation of mineral refers to the use of mineral resources for economic growth. Exploitation of mineral resources at a mindless speed to meet the growing needs of modern civilization has resulted in many environmental problems.

Although, the exploitation of minerals began at a slow pace during the industrial revolution in Western countries, during the 20^th century, the exploitation of some minerals, especially the fossil fuels increased exponentially to meet the growing energy need. Today, about 80% of the world’s energy consumption is sustained by the extraction of fossil fuels, which consists of oil, coal, and gas.

Consequences of Exploitation of Mineral Resources.

Excessive exploitation of mineral resources has led to the following severe problems.

• Deforestation and desertification
• Extinction of species
• Rapid depletion of high grade minerals
• Forced migration
• Wastage of upper soil layer and vegetation
• Soil erosion and oil depletion
• Ozone depletion
• Greenhouse gas increase
• Environmental pollution
• Natural hazards, etc.

Environmental Studies - Land Resources

Land is a naturally occurring finite resource. It provides the base for survival of living beings. It holds everything that constitutes terrestrial ecosystems. Increased demand on land in modern times due to the rise in human population and resultant activities has resulted in degradation of land quality and quantity, decline in crop production, and competition for land.

Land and Land Resources refer to a delineable area of the earth's terrestrial surface, encompassing all attributes of the biosphere immediately above or below this surface, including those of the near-surface climate, the soil and terrain forms, the surface hydrology (including shallow lakes, rivers, marshes and swamps), the near-surface sedimentary layers and associated groundwater and geo-hydrological reserve, the plant and animal populations, the human settlement pattern and physical results of past and present human activity (terracing, water storage or drainage structures, roads, buildings, etc.)

Forest Resources

Forests are the dominant terrestrial ecosystem of Earth, and are distributed across the globe. Forests account for 75% of the gross primary productivity of the Earth's biosphere, and contains 80% of the Earth's plant biomass.

A forest constitutes many components that can be broadly divided into two categories that are biotic (living) and abiotic (non-living) components. Forest is made up of many layers such as forest floor, understory, canopy, and emergent layer.

Forests can be classified in various ways such as Boreal, Temperate, Tropical types with their numerous subtypes. Due to increasing population and consequential expansion of modern civilization, there has been continuous depletion of natural forests over the centuries.

In 1990, the world had 4128 million ha of forest; by 2015 this area had decreased to 3999 million ha. This is a change from 31.6 percent of global land area in 1990 to 30.6 percent in 2015. Average per capita forest area declined from 0.8 ha to 0.6 ha per person from 1990 to 2015.

Over the past 25 years, global carbon stocks in forest biomass have decreased by almost 11 gigatonnes (Gt). This reduction has been mainly driven by conversion to other land uses and to a lesser extent by forest degradation.

Usefulness of Forest Resources

• Forest is an important natural resource. Forests are vital for the ecological balance and play an important role in temperature regulation in the atmosphere.

• Forests are natural and vast reservoir of food and shelter for animals. They provide natural habitats for numerous species of plants, animals and micro-organisms.

• Forests provide timber, bamboo, canes, leaves, grass, oil, resins, gums, shellac, tanning materials, dyes, hides, fur, fruits, nuts, roots, tubers and other useful things for human beings.

• Forests provide raw materials for forest-based industries.

• Forests are the natural home to medicinal herbs and plants.

• Forest directly or indirectly affects the climate (temperature, precipitation, moisture, underground water-table).

• Forests prevent floods and soil erosion, land degradation and improve the quality of air and water.

• Forests help in purifying air, water, and soil pollution.

Environmental Studies - Energy Resources

Energy is defined by physicists as the capacity to do work. Energy is found on our planet in a variety of forms, some of which are immediately useful to do work, while others require a process of transformation. The sun is the primary energy source in our lives. Besides, water, fossil fuels such as coal, petroleum products, water, nuclear power plants are sources of energy.

Growing Energy Needs

Energy has always been closely linked to man’s economic growth and development. Present strategies for development that have focused on rapid economic growth have used energy utilization as an index of economic development. This index, however, does not take into account the long-term ill effects on society of excessive energy utilization.

For almost 200 years, coal was the primary energy source fueling the industrial revolution in the 19th century. At the close of the 20th century, oil accounted for 39% of the world’s commercial energy consumption, followed by coal (24%) and natural gas (24%), while nuclear (7%) and hydro/renewable (6%) accounted for the rest.

Industrialization, urbanization, and unbelievable rise in human settlements have multiplied the energy requirement by several times. Modern lifestyle and man’s growing dependence on machines and equipment for his personal and professional work has added to the energy demand. Global oil demand continues to grow until 2040, mostly because of the lack of easy alternatives to oil in road freight, aviation and petrochemicals, according to WEO-2016, published by International Energy Agency.

Renewable Energy Resources

Renewable energy systems use resources that are constantly replaced and are usually less polluting. Examples include hydropower, solar, wind, and geothermal (energy from the heat inside the earth). We also get renewable energy from burning trees and even garbage as fuel and processing other plants into bio-fuels.

Wind Energy

The moving air or wind has huge amounts of kinetic energy, and it can be transferred into electrical energy using wind turbines. The wind moves the blades, which spins a shaft, which is further connected to a generator, which generates electricity. An average wind speed of 14 miles per hour is needed to convert wind energy into electricity. Windgenerated electricity met nearly 4% of global electricity demand in 2015, with nearly 63 GW of new wind power capacity installed.

Solar Energy

Solar energy is the light and heat procured from the sun. It is harnessed using an everevolving technologies. In 2014, global solar generation was 186 terawatt-hours, slightly less than 1% of the world’s total grid electricity. Italy has the largest proportion of solar electricity in the world. In the opinion of International Energy Agency, the development of affordable, inexhaustible, and clean solar energy technologies will have longer-term benefits.

Biomass Energy

When a log is burned we are using biomass energy. As plants and trees depend on sunlight to grow, biomass energy is a form of stored solar energy. Although wood is the largest source of biomass energy, agricultural waste, sugarcane wastes, and other farm byproducts are also used to produce energy.

Hydropower

Energy produced from water is called hydropower. Hydroelectric power stations both big and small are set up to produce electricity in many parts of the world. Hydropower is produced in 150 countries, with the Asia-Pacific region generating 32 percent of global hydropower in 2010. In 2015, hydropower generated 16.6% of the world’s total electricity and 70% of all renewable electricity.

Tidal and Wave Power

The earth’s surface is 70% water. By warming the water, the sun creates ocean currents and the wind that produces waves. It is estimated that the solar energy absorbed by the tropical oceans in a week could equal the entire oil reserves of the world – 1 trillion barrels of oil.

Geothermal Energy

It is the energy stored within the earth (“geo” for earth and “thermal” for heat). Geothermal energy starts with hot, molten rock (called magma) deep inside the earth which surfaces at some parts of the earth’s crust. The heat rising from the magma warms the underground pools of water known as geothermal reservoirs. If there is an opening, hot underground water comes to the surface and forms hot springs, or it may boil to form geysers. With modern technology, wells are drilled deep down the surface of the earth to tap into geothermal reservoirs. This is called direct use of geothermal energy, and it provides a steady stream of hot water that is pumped to the earth’s surface.

Environmental Studies - Biodiversity

Biodiversity, a shortened form of Biological diversity, refers to the existence of number of different species of plants and animals in an environment.

The Convention on Biological Diversity (1992) of the United Nations gives a formal definition of biodiversity in its Article 2: "Biological diversity means the variability among living organisms from all sources including, inter alia, terrestrial, marine, and other aquatic ecosystems and the ecological complexes of which they are part; this includes diversity within species, between species and of ecosystems."

Biodiversity is also defined as the existence of variability among living organisms on the earth, including the variability within and between species, and within and between ecosystems.

Species Diversity

Species diversity refers to the variety of different species of plants, animals, fungi, and organisms that are present in a region. It is estimated that there are above 30 million species on the earth. Species diversity is a part of diversity. Even within a small pond, we can notice a great variety of species. Species diversity differs from ecosystem to ecosystem. For example, in a tropical ecosystem more diversity is found than in temperate ecosystem. The most diverse group of species is invertebrates - animals without backbones.

At present, conservation scientists have been able to identify and categorize about 1.8 million species on earth. Many new species are being identified. Areas that are rich in species diversity are called ‘hotspots’ of diversity.

Genetic Diversity

It is the variation in genes that exists within a species. Genetic diversity corresponds to the variety of genes contained in plants, animals, fungi, and micro-organisms. It occurs within a species as well as between species. For example, poodles, German shepherds and golden retrievers are all dogs, but they all are different in look, color, and abilities. Each human being is different from all others. This genetic variability is essential for a health breeding of a population of species.

The diversity in wild species make the ‘gene pool’ from which crops and domestic animals have been developed over thousands of years.

Ecosystem Diversity

It is the diversity of ecosystems, natural communities, and habitats. In other words, ecosystem diversity refers to the variety of ways that species interact with each other and their environment. Tropical or temperate forests, grasslands, hot and cold deserts, wetlands, rivers, mountains, and coral reefs are instances of ecosystem diversity.

Each ecosystem corresponds to a series of complex relationships between biotic (living) and abiotic (non-living) components.

Value & Productive Use of Biodiversity

The importance of biodiversity is second to none. It boosts the ecosystem of productivity where each species, irrespective of their size, have an important role to play. Greater diversity in species ensure natural sustainability for all life forms. Hence, there is a need to preserve the diversity in life on the earth.

According to the UN sources at least 40 percent of the world’s economy and 80 percent of the needs of the poor are derived from biological resources. In addition, the richer the diversity of life, the greater the opportunity for medical discoveries, economic development, and adaptive response to such new challenges as climate change.

Significance of Biodiversity

Environmental services from species and smooth running cycles of ecosystems are necessary at global, regional, and local levels.

Biodiversity is essential for maintaining the water cycles, production of oxygen, reduction in carbon dioxide, protecting the soil, etc. It is also essential for preserving ecological processes, such as soil formation, circulation of and cleansing of air and water, global life support, fixing and recycling of nutrients, maintaining hydrological balance within ecosystems, maintaining rivers and streams throughout the year, etc.

Biodiversity has many values such as consumptive use value, productive use value, social values, ethical and moral values.

A healthy biodiversity offers many valuable services as follows.

• The more a region is rich in terms of biodiversity, better is the regulation of the different cycles. For example, forests regulate the amount of carbon dioxide in the air by releasing oxygen as a by-product during photosynthesis, and control rainfall and soil erosion.

• Protects water resources from being depleted, contaminated, or polluted.

• Helps in soil formation and protection.

• Helps in nutrient storage and recycling.

• Helps check pollution.

• Contributes to climate stability.

• Helps an ecosystem in recovery from unpredictable events.

• Provides biological resources such as food, medicinal resources, and pharmaceutical drugs, wood products, ornamental plants, breeding stocks, etc.

• Provides recreation and tourism facilities.

• Helps in research, education, and monitoring.

• Preservation of biological resources is essential for the well-being and long-term survival of mankind.

Productive Use Value of Biodiversity

Productive Use Value refers to the commercial value of products that are commercially harvested for exchange in formal markets.

Modern civilization is invariably a gift of biodiversity. The food we eat, the medicine we take in, the furniture we use, the industries, for example, are derivatives of biological diversity.

The agricultural crops of the present day have originated from wild varieties. Biotechnologists use the wild plants for developing new, high-yielding, and pest or diseaseresistant varieties. Biodiversity is home to original stock from which new varieties are being developed.

Similarly, all our domesticated animals came from their wild-living ancestral species. With the help of scientific breeding techniques, animals giving better yield of milk, meat, etc. are being developed. The animal products used by modern society come from the advances made in the fields of poultry farming, pisciculture, silviculture, dairy farming, etc.

Fossil fuels, considered to be pivotal in modern society, such as coal, petroleum, and natural gas are gifts of biodiversity from the geological past.

Most of the pharmaceutical drugs and medicines used in the present time are extracted from different plants.

Biodiversity provides rich storehouse for industrialists and entrepreneurs to develop new products. It provides agricultural scientists and biotechnologists with ample scope for developing new and better crops. New crop varieties are being developed using the genetic material found in wild relatives of crop plants though biotechnology.

The need of the hour is the preservation of biodiversity for industrial, economic, and above all, environmental safety. This is called ‘biological prospecting’.

Biodiversity Hotspots

The Earth’s biodiversity is evenly distributed across its surface. There are over a thousand major eco-regions in the world. It is estimated that there are about 200 richest, rarest and most distinctive natural areas in the world. These are referred to as the Global 200.

Hotspots of biodiversity refer to bio-geographic regions where significant levels of biodiversity with richness and unusual concentration of endemic species are found, however, they are threatened with mindless exploitation and destruction.

A biodiversity is termed as a hotspot if −

• It has at least 1,500 vascular plants as endemic.

• It must be threatened or under threat of destruction to a considerable extent.

Across the world, about 35 areas are marked as hotspots of biodiversity and they represent 2.3 percent of the Earth’s land surface but they support more than half of the world’s endemic plant species and almost half of birds, mammals, reptiles, and amphibians as endemic.

List of Biodiversity Hotspots in the World

North and Central America − California Floristic Province, Madrean pine-oak woodlands, Mesoamerica

The Caribbean − Caribbean Islands

South America − Atlantic Forest, Cerrado, Chilean Winter Rainfall-Valdivian Forests, Tumbes-Chocó-Magdalena, Tropical Andes

Europe − Mediterranean Basin

Africa − Cape Floristic Region, Coastal Forests of Eastern Africa, Eastern Afromontane, Guinean Forests of West Africa; Horn of Africa; Madagascar and the Indian Ocean Islands; Maputaland-Pondoland-Albany; Succulent Karoo

Central Asia − Mountains of Central Asia

South Asia − Eastern Himalaya, Nepal; Indo-Burma, India and Myanmar; Western Ghats, India; Sri Lanka

South East Asia and Asia-Pacific − East Melanesian Islands; New Caledonia; New Zealand; Philippines; Polynesia-Micronesia; Southwest Australia; Sundaland; Wallacea

East Asia − Japan; Mountains of Southwest China

West Asia − Caucasus; Irano-Anatolian

About 1.8 million species are known to mankind at present. Scientists, however, have estimated that the number of species of plants and animals on the earth can go up to 20 billion. It means a majority of species still remain undiscovered.

World’s most prolific bio-rich nations are in the south. On the other hand, the majority of the countries capable of exploiting biodiversity are the developed Northern countries. These countries have very low level of biodiversity.

Developed nations want to consider biodiversity as ‘global resources’. However, nations rich in biodiversity like India don’t want to compromise their sovereignty over their biological diversity unless there is a revolutionary change in global thinking about sharing of all types of natural resources such as rare minerals as uranium, oil, or even intellectual and technological resources.

India is home to rich biodiversity. Countries with diversities higher than India are located in South America such as Brazil, and South East India countries such as Malaysia and Indonesia.

Biological diversities are now being increasingly appreciated as being of unimaginable value. International initiatives such as World Heritage Convention, Biodiversity Action Plan (BAP) aims for the protection and support of biologically rich natural areas and address threatened species and habitats to protect and restore biological systems.

Convention in the Trade of Endangered Species (CITES) is intended to reduce the utilization of endangered plants and animals by controlling trade in their products and in pet trade.

India as a Mega Diversity Region

A mega diversity region or country is one that harbors majority of the Earth’s species and is therefore considered extremely bio-diverse. India is rich in biodiversity from north to south and from east to west. Geological events in the landmass of India, different climatic regions across the country and its special geographical position between a couple of distinct biological evolution and radiation of species are responsible for India’s rich and varied biodiversity.

India is one among the top 10 countries with rich biodiversity and one among the 12 Mega biodiversity regions in the world. Around 18 biosphere reserves have been set up in India.

India is home to 350 different mammals (rated highest in the world), 1, 200 species of birds, 453 species of reptiles and 45, 000 plant species. India is home to 50, 000 known species of insects, that include 13, 000 butterflies and moths. It is estimated that the number of unnamed species could be much higher than the existing number.

More than 18 percent of Indian plants are endemic (native to a particular region) to the country and found nowhere else in the world.

India has 27 indigenous breeds of cattle, 40 breeds of sheep, 22 breeds of goats and 8 breeds of buffaloes.

Among the amphibians found in India, 62 percent are unique to this country. High endemism has also been recorded in various flowering plants, insects, marine worms, centipedes, mayflies, and fresh water sponges.

Apart of noticeable diversity in Indian wild plants and animals, there is also a great diversity of cultivated crops and breeds of domestic livestock. The traditional cultivars (a plant variety that has been produced in cultivation by selective breeding) include about 50,000 varieties of rice and a number of cereals, vegetables, and fruits. The highest diversity of cultivars is found concentrated in the high rainfall areas of Western Ghats, Eastern Ghats, Northern Himalayas. and North-Eastern hills.

Threats to Biodiversity

Biodiversity is a paramount factor for the survival of the living world in general and mankind in particular. The fewer species (animals and plants) we have, the fewer people we will have on the earth. During the last few decades, loss of biodiversity is on the rise. Following are the major causes of threat to biodiversity.

Habitat Loss

Today, major loss to biodiversity in the world has been done by man. Man has begun to overuse or misuse most of these natural ecosystems.

Due to mindless and unsustainable resource use, once productive forest and grasslands have been turned into deserts, and wastelands have increased all over the world. Rapid industrialization, urbanization, and growth in population have resulted in massive deforestation and consequential habitat loss around the world.

For instance, mangroves have been cleared for fuel-wood and prawn farming, which has led to a decrease in the habitat essential for breeding of marine fish.

Forests all over the world, in particular tropical rainforests such as the Amazon, are under unforeseen threat largely from conversion to other land-uses.

Scientists have estimated that human activities are likely to eliminate approximately10 million species by the year 2050. It is also estimated that at the present rate of extinction about 25 percent of the world’s species will undergo extinction fairly rapidly. Rich biodiversities such as tropical forests, wetlands, and coral reefs world over will constitute the major part of this extinction.

Poaching of Wildlife

Poaching of wildlife for trade and commercial activities has been on the rise for the last many decades. It has been a significant cause of the extinction of hundreds of species and the endangerment of many more, such as whales and many African large mammal, Asian tigers, etc. Most extinction over the past several hundred years is mainly due to overharvesting for food, fashion, and profit.

Illicit trade in wildlife in current times is driving many species of wild animals and plants to extinction. Elephants are poached for ivory; tigers and leopards for their skin; pangolins for meat and scales; and rare timber is targeted for hardwood furniture.

The global illegal wildlife trade is estimated to be between $7 billion and $23 billion in illicit revenue annually. It is now considered the most lucrative global crime after drugs, humans, and arms.

In 2015, the United Nations General Assembly unanimously adopted a resolution for tackling illicit trafficking in wildlife. The Sustainable Development Goals has laid down specific targets to combat poaching and trafficking of protected species.

Man-Wildlife Conflict

Man-wildlife conflict refers to the interaction between wild animals and people and the consequential negative impact on both of them. Human population growth and the resultant destruction of wildlife habitat for human habitation and economic prosperity create reduction of resources or life to some people and wild animals.

World Wide Fund for Nature (WWF) defines this conflict as “any interaction between humans and wildlife that results in a negative impact on human social, economic, or cultural life, on the conservation of wildlife population, or on the environment.”

Although man-wildlife conflict is as old as human civilization, in modern times the degree of conflict has been on the rise due to high rise in human population in the past several centuries.

Since human populations expand into wild animal habitats, natural wildlife territory is displaced. Reduction in the availability of natural prey/food sources leads to wild animals seeking alternate sources. Alternately, new resources created by humans draw wildlife resulting in conflict. Competition for food resources also occurs when humans attempt to harvest natural resources such as fish and grassland pasture.

There are many consequences of man versus wildlife conflicts. The major consequences are −

• Destruction of wildlife habitat
• Injury and loss of life of both humans and wildlife
• Crop damage and livestock depredation
• Damage to human property
• Decrease in wildlife population and reduction in geographic ranges
• Trophic cascades

Apart from the above, there are other causes of threat to biodiversity. Factors such as climate change, invasion of non-native species also add to biodiversity losses in some or the other.

Conversation of Biodiversity

Considering the degree of threat to biodiversity around the world and the vital importance of biodiversity for living beings of which mankind is a major part, there is an urgent need to conserve biodiversity in the world. Further, we should be concerned about saving biodiversity because of the benefits it provides us – biological resources and ecosystem services, and the social and aesthetic benefits.

There are two main methods for the conservation of biodiversity.

In-situ Conservation

In-situ or on-site conservation refers to the conservation of species within their natural habitats. This is the most viable way of biodiversity conservation. It is the conservation of genetic resources through their maintenance within the environment in which they occur.

Examples − National Parks, Wild Life sanctuaries, Biosphere Reserves, Gene Sanctuaries

Ex-situ Conservation

Ex-situ conservation means the conservation of components of biological diversity outside their natural habitats. In this method, threatened or endangered species of animals and plants are taken out of their natural habitat and placed in special settings where they can be protected and provided with natural growth.

In ex-situ conservation methods, the plants and animals taken away from their habitats are taken care of in an artificially created environment.

Examples − Captive Breeding, Gene Banks, Seed Banks, Zoos, Botanical gardens, Aquaria, In vitro fertilization, Cryopreservation, Tissue Culture.

National Biodiversity Act

National Biodiversity Act in India draws from the objectives of Convention of Biodiversity (CBD). It aims at conservation of biodiversity, sustainable use and equitable sharing of the benefits of such use.

To achieve its objectives, it has put in place a three-tier institutional structure such as −

• National Biodiversity Authority based in Chennai
• State Biodiversity Board (SBBs) in every state
• Biodiversity Management Committee (BMCs) at Panchayat/Municipality levels

The Ministry of Environment and Forestry (MoEF) is the nodal agency.

Main Provisions of the Act

• Prohibition on transfer of Indian genetic material outside the country without specific approval of the Indian Government.

• Prohibition of anyone claiming an IPR such as a patent over biodiversity or related knowledge without the permission of Indian Government.

• Regulation of collection and use of biodiversity by Indian national, while exempting local communities from such restrictions.

• Measures from sharing of benefits from the use of biodiversity including transfer of technology, monitory returns, joint research and development, joint IPR ownership, etc.

• Measures to conserve sustainable use of biological resources including habitat and species protection projects, integration of biodiversity into the plans and policies of the various departments and sectors.

• Provisions for local communities to have a say in the use of their resources and knowledge and to charge fees for this.

• Protection of indigenous or traditional laws such as registration of such knowledge.

• Regulation of the use of the genetically modified organisms.

• Setting up of national, state and local biodiversity funds to be used to support conservation and benefit sharing.

• Setting up of Biodiversity Management Committees (BMC) at local village levels. State Biodiversity Boards at state level and National Biodiversity Authority.

Environmental Studies - Pollution and Control

Environmental pollution or simply pollution refers to undesirable changes occurring in the physical, chemical, and biological composition of natural environment consisting of air, water, and soil. Pollution also means the presence of harmful pollutants in an environment that makes this environment unhealthy to live in.

According to National Academy of Science, USA (1966), pollution is defined as, “An undesirable change in physical, chemical, and biological characteristics of water, air, and soil that may harmfully affect human, animal, and plant life, industrial progress, living conditions and cultural assets.

Pollution is also viewed as ‘an unfavorable alteration’ in the sustaining and carrying capacity of the natural environment wholly or largely by the byproducts of human activities. Natural environment has an inbuilt capacity to replenish the losses or reduction in its constituents to restore it as sustainable and healthy as required.

Ever expanding population and evolution of man into modern homo sapiens have led to rapid urbanization, industrialization and unprecedented rise in human habitations. All these human endeavors have, in turn, virtually perpetuated deforestation, loss of habitats for flora and fauna, depletion of natural resources at a large scale over the last couple of centuries, which have told upon the inherent resilience of the natural environment. As a result, natural environment continues to be undesirably polluted.

Pollutants

A pollutant is defined as any form of energy or matter or action that causes imbalance or disequilibrium in the required composition of natural objects such as air, water, etc. A pollutant creates damage by interfering directly or indirectly with the biogeochemical process of an organism.

Pollutants may be −

• Natural Pollutants − Natural pollutants are caused by natural forces such as volcanic eruption and forest fire.

• Man-made Pollutants − These refer to the release of excess amount of gases or matter by human activities. For instance, increase in the number of automobiles adds excess carbon monoxide to the atmosphere causing harmful effect on vegetation and human health.

Classification of Pollution

Different types of pollution are classified based on the part of the environment which they affect or result caused by a particular pollution. Each type of pollution has its own distinctive cause and consequences.

The major types of pollution are as follows.

• Air pollution
• Water pollution
• Noise pollution
• Soil or land pollution

Environmental Studies - Air Pollution

Every day, every moment, we breathe polluted air and may become a victim of air pollution. It is estimated that an average adult exchanges 15 kg of air a day, in comparison to about 1.5 kg of the food consumed and 2.5 kg of water intake. It is obvious that the quantum of pollutants that enter our body through respiration would be manifold in comparison to those taken in through polluted water or contaminated food.

Air pollution is one of the most widespread forms of pollution all over the world. Wind is the main agent of air pollution. It gathers and moves pollutants from one area to another, sometimes reducing the concentration of pollutants in one location, while increasing it in another.

Causes of Air Pollution

Apart from the natural causes of pollutants, as stated above, human interaction and resource utilization is perhaps adding more pollutants to the atmosphere.

• Industrialization − Industries big or small require steam to run. The steam is produced by burning fossil fuels such as coal, coke, and furnace oil. These fuels while burning release toxic gases in large amount into the atmosphere.

• Automobiles − To meet the demands of exploding human population, the number of automobiles is increasing at a great space. The automobile exhausts are responsible for about sixty percent of air pollution. Released carbon monoxide from the automobiles pollutes the air and harms trees and other natural vegetation. It also has ill-effects on human health.

• Chlorofluorocarbons − Scientists are now alarmed regarding the increased concentration of chemical substances together called chlorofluorocarbon in the atmosphere. These substances are responsible for creating holes in the ozone layer causing unwanted imbalance in the heat budget. These are produced by modern gadgets such as air conditioners, refrigerators, dyers, etc.

The adverse effects of air pollution appear in the form of poor quality of air, acidic precipitation (rain, snow and hail) and deposition, and other health hazards.

The main pollutants of air are carbon dioxide (CO₂ ), carbonic acid (H ₂SO₂), water (H₂O), nitric acid (HNO₃O ), and sulphuric acid (H₂SO₄ ).

Air pollution has harmful effects on natural vegetation and human health such as respiratory illnesses. Acidic precipitation is highly fatal for aquatic flora and fauna, monuments, and also for natural vegetation.

Air Pollution Control

Air pollution control is an onerous task as there are large number of pollutants involved in air pollution. Some of these are even difficult to detect. However, there can be some basic approaches to control air pollution. They are as follows.

Preventive Approach

It is well said that prevention is better than cure. We can prevent pollutants of air from being produced by various ways. For instance, by changing raw materials used in industry or the ingredient of fuel from conventional to non-conventional sources of energy; by maintenance of vehicles and roads and efficient transport system; by reduction in garbage burning and shifting cultivation areas; afforestation, etc.

Dispersal Approach

We can prevent air pollution by raising the heights of smokestacks in industries so as to release the pollutants high into the atmosphere.

Collection Approach

Air pollution can be controlled by designing the equipment and machinery to trap pollutants before they escape into the atmosphere. To meet the standards, automobile engines have been re-designed and new cars have been equipped with devices such as the catalytic converter, which changes the pollutants into harmless substances. Because of these new devices, air pollution from car exhaust has also been reduced.

Legislation Approach

There have been many initiatives in different countries for making laws, setting standards and norms to check air pollution and ensure quality air. All the highly industrialized countries of the world have certain legislations to prevent and control air pollution. As pollutants of air are carried by the wind from one country to another for thousands of miles, there should be global initiatives agreed upon by all countries to save the earth from the menace of air pollution.

Environmental Studies - Water Pollution

Water pollution may be defined as alteration in physical, chemical, and biological characteristics of water, which may cause harmful effects on human and aquatic life.

Pollutants of Water

Following are some of the reasons for water pollution.

• Disposal of sewage and sludge into water bodies such as river, streams, and lakes.

• Inorganic compounds and minerals by mining and industrial activities.

• Use of chemical fertilizers for agricultural purposes.

• Synthetic organic compounds from industrial, agricultural, and domestic garbage.

• Oil and petroleum from tankers’ accident, offshore drilling, combustion engine, etc.

• Radioactive wastes

Water Pollution Control

• Environmental Education − Individuals and the masses should be educated about the significance of quality of water and its impact on the economy, the society, and ecology.

• Sewage Treatment − The household water should be treated properly to make it environmentally safe. Necessary steps should be taken to ensure that effective sewage treatment process is put in place and contaminated water doesn’t get mixed with the fresh water bodies.

• Accountability of Industrial Units − The industrial setups should make provisions for treatment of waste materials and water, and for its safe drainage.

• Afforestation − Planting trees can reduce the water pollution to a large extent as they check surface soil runoff by running water.

• Soil Conservation − Soil conservation add many inorganic substances in the surface and underground water. Soil conservation is, therefore, a useful technique to reduce water pollution.

• Reduced Use of Chemical Fertilizers − Chemical fertilizers add nitrates in water bodies. Use of compost manures can help reduce the problem of eutrophication in the water bodies.

• Financial Support − Governments should make provisions for adequate funds to the civic bodies for water pollution control.

• Legislation and Implementation of Stringent Environmental Laws − The need of the hour is that the government should legislate and implement strict environmental laws for the protection of water bodies, treatment of waste water, etc. The violators of such laws should be given exemplary punishment.

Environmental Studies - Noise Pollution

Noise pollution refers to any unwanted and unpleasant sound that brings discomfort and restlessness to human beings. Like air and water pollution, noise pollution is harmful to human and animal life.

Noise pollution is also an important environmental hazard, which is becoming growingly injurious in many parts of the world. Noise beyond a particular level or decibel (unit of noise) tends to become a health and environmental hazard.

Sources of Noise Pollution

• Household appliances such as grinders, electric motor, washing machines
• Social gatherings such as marriages and other social parties
• Places of worship
• Commercial activities
• Construction activities
• Industrial activities
• Automobiles and transport system
• Power generators
• Agricultural equipment

Noise Pollution Control

According to the World Health Organization (WHO), of all the environmental pollution, noise is the easiest to control.

Noise pollution can be checked at home by −

• Turning off sound-making appliances when they are not in use.
• Shutting the door when noisy machines are being used.
• Lowering the volume of appliances such as television to a desirable level.
• Using earplugs while listening to music.

At mass level it can be checked by −

• By planting trees in large number to create vegetation buffer zones, which absorb noise.

• Public awareness about the need of control of noise pollution.

• Application of engineering control techniques such as alteration and modification of design to reduce noise from equipment and machinery, and by construction of sound barriers or the use of sound absorbers in industrial and factory sites can reduce exposure to noise to a great extent.

• Construction of institutions and hospitals away from airports, railways, and highways.

• Improved building design may also reduce the impact of noise pollution.

• Stringent legislations at central and state levels to check air pollution at workplaces, urban centers, etc.

Environmental Studies - Soil Pollution

Soil pollution refers to an undesirable decrease in the quality of soil, either by man-induced sources or natural sources or by both.

Soil is vital not only for the growth of plants and growing food but also cultivating raw materials for agro-based industries. Health soil is a significant prerequisite for human survival.

Causes of Soil Erosion

• Deforestation at large scale
• Over-grazing
• Mining
• Decrease in soil microorganisms
• Excessive use of chemical fertilizers
• Excessive use of irrigation
• Lack of humus content
• Improper and unscientific rotation of crops

Soil pollution leads to many harmful consequences such as decrease in agricultural production; reduced nitrogen fixation; reduction in biodiversity; silting of tanks, lakes and reservoirs; diseases and deaths of consumers in the food chain due to use of chemical fertilizers and pesticides, etc.

Soil Pollution Control

• Adoption of soil-friendly agricultural practices.

• Use of compost manures in place of chemical fertilizers; Use of bio-fertilizers and natural pesticides help in minimizing the usage of chemical fertilizers and pesticides

• Scientific rotation of crop to increase soil fertility.

• Proper disposal of industrial and urban solid and liquid wastes.

• Planting of trees to check soil erosion in slopes and mountainous regions.

• Controlled grazing.

• Reduction in the heaps of garbage and refuse.

• The principles of three R’s − Recycle, Reuse, and Reduce − help in minimizing generation of solid waste.

• Formulation and effective implementation of stringent pollution control legislation.

• Improved sewage and sanitation system in urban areas.

Solid Waste Management

Solid waste management refers to the collecting, treating, and disposing of solid material that is discarded or is no longer useful. Solid waste management is an important aspect of urban area management. Improper disposal of municipal solid waste can create unsanitary conditions, which can lead to environmental pollution and the outbreak of vector-borne disease.

The task of solid waste management presents complex technical challenges. They also pose various economic, administrative, and social problems which need urgent attention.

The major sources of solid waste are households; agricultural fields; industries and mining, hotels and catering; roads and railways; hospitals and educational institutions; cultural centers and places of recreation and tourism, etc. Plastic waste is also a solid waste.

Classification of Solid Wastes

• Municipal Waste
• Hospital Waste
• Hazardous Waste

Effective Solid Waste Management can be carried out in the following ways −

• Sanitary landfills
• Composting
• Landfills
• Incineration and pyrolysis (a process of combustion in the absence of oxygen)
• Vermiculture or earthworm farming
• Bioremediation or the use of micro-organism (bacteria and fungi)
• Reuse, reduce, and recycle

Hazardous Waste Management

Hazardous waste (HW) is defined as any substance, in solid, liquid or gaseous form, which has no use in future and which causes danger or is likely to cause danger to health and environment.

The hazardous waste requires to be disposed of in a secured manner in view of their characteristic properties. When HWs are not used efficiently by the waste generators, they cause severe pollution of land, surface, and ground water.

Components of Hazardous Waste Management

• Identification of hazardous waste generation by industries and other sources.

• Characterization of hazardous waste pertaining to physical, chemical, and general characteristics and properties pertaining to ignitability, corrosiveness, reactivity and toxicity.

• Quantification of hazardous waste in order to facilitate safe disposal.

• Identification of sites for disposal.

• Environmental impact assessment should be conducted and public acceptance should be accepted for the sites.

• Hazardous waste management rules are notified to ensure safe handling, generation, processing, treatment, package, storage, transportation, use reprocessing, collection, conversion, and offering for sale, destruction, and disposal of hazardous waste.

Proper treatment, storage prior to treatment or disposal of hazardous waste is the need of the hour. Governments should make provisions for and prepare guidelines for the industries and other hazardous waste generating sources for safe disposal or treatment of hazardous waste.

Water Waste Management

Wastewater refers to any water that is not clean or is adversely affected in quality by human-induced activities. Wastewater originates from a combination of domestic, industrial, commercial, or agricultural activities.

Wastewater treatment or management refers to the processes used to convert wastewater into an effluent that can be either returned to the water cycle with negligible environmental impact or can be reused.

The major objective of wastewater treatment is generally to allow human and industrial effluents to be disposed of without danger to human health or unacceptable damage to the natural environment.

Wastewater Treatment Process

Phase Separation − It transfers impurities into a non-aqueous phase.

Sedimentation − Sedimentation is a physical water treatment process using gravity to remove suspended solids from water. Solid particles entrained by the turbulence of moving water may be removed naturally by sedimentation in the still water of lakes and oceans.

Filtration − Suspension of fine solids may be removed by filtration through physical barriers such as coarser screens or sieves.

Oxidation − This process diminishes the biochemical oxygen demand of wastewater and may reduce the toxicity of some impurities. Advanced Oxidation Processes (AOPs) are a set of chemical treatment of wastewater purported to remove organic and also inorganic materials in waste water by oxidation through reaction with hydroxyl radicals.

Chemical oxidation may remove some persistent organic pollutants and concentrations remaining after biochemical oxidation.

Wastewater treatment plants are set up for effective treatment of wastewater. They may be distinguished by the type of wastewater to be treated. They are as follows.

• Sewage treatment plants
• Industrial wastewater treatment plants
• Agricultural wastewater treatment plants

Global Environmental Problems

Climate refers to the usual weather of a place. Climate differs from season to season, from region to region. A combination of all the climates of the world is termed as the Earth’s climate.

Climate Change

Climate change refers to a change or changes in the usual weather condition found in a place or region. Changes could be experienced in the rainfall or snowfall pattern, temperature, etc. Climate change is also a change in Earth’s climate.

Climate change is now a much-discussed concept around the globe. It is because it is now experienced that the world temperature is increasing during these years. The global average surface temperature is believed to have increased by 0.6° + 0.2° C over the last century. Globally, 1998 was the warmest year and the 1990s was the warmest decade on record.

Many countries have experienced increases in rainfall, particularly in the countries situated in the mid to high latitudes. In some regions, such as parts of Asia and Africa, the frequency and intensity of droughts have been observed to increase in recent decades.

Episodes of El Nino, which creates great storms, have been more frequent, persistent, and intense since mid-1970s compared with the previous 100 years. All these signs show that the earth’s climate is changing, making it more difficult for mankind to survive.

Causes of Climate Change

Climate changes on its own in nature. Earth’s distance from the sun, volcanic eruption at large scale, heavy rainfall for longer period, are the instances of natural phenomena that influence the Earth’s climate. These are natural and have nothing to do with our present concern about climate change.

What concerns us today is the rise in global temperature, especially. Most scientists say that human activities have caused certain changes in the natural climate of the earth.

Most scientists agree that the main cause of current global warming is human expansion of the ‘greenhouse effect’. Greenhouse effect is the increase in the number of certain gases that include, carbon dioxide (CO₂), methane, nitrous oxide (N₂O), water vapor, chlorofluorocarbons (CFCs), etc.

Greenhouse gases are produced naturally and trap heat in the Earth’s atmosphere like a blanket. When there is increased concentration of such gases in the atmosphere mostly by burning fossil fuels, there is a proportionate increase in the temperature of the Earth’s atmosphere. It is called global warming.

Significant human-led factors responsible for climate change are −

• Exponential growth in human population.

• Massive and unplanned urbanization and industrialization over the last century.

• Burning of fossil fuels such as coal, petroleum, and natural gas at huge scale to meet the growing energy needs of the bulging world population.

• Change in lifestyle and massive increase in the number of machinery, gadgets, etc.

Impact of Climate Change on Human Environment

It is now clear that climate change causes unwanted alterations in the natural systems. The environmental consequences of climate change are extreme heat waves, rising sea levels, changes in precipitation resulting in flooding and droughts, intense hurricanes, and degraded air quality.

The above phenomenal changes directly and indirectly affect the physical, social, and psychological health of human beings.

Frequency in Weather-Related Disasters

Changes in precipitation create changes in the availability and quantity of water and also results in extreme weather events, such as intense storms, flooding and droughts. Frequency in all these weather phenomena sometimes lead to human causality in great proportion apart from huge loss of property, mostly in developing and underdeveloped countries.

Human Health

Climate change affects the prerequisites of human health such as clean air and water, sufficient and healthy food, natural constraints to infectious disease agents and the adequacy and security of shelter.

The report of the WHO Commission on Social Determinants of Health points out that disadvantaged communities are likely to shoulder a disproportionate share of the burden of climate change because of their increased exposure and vulnerability to health threats.

Large Scale Displacement of People

Climate change effects such as desertification, rising sea levels and severity of weatherrelated disasters along with the spread of epidemics can destroy or affect human habitation causing people to seek shelter elsewhere.

Deteriorating environment and depleting resources can result in human conflicts at all levels. The Intergovernmental Panel on Climate Change (IPCC) has estimated that there will be over 150 million environmental migrants by 2050 and the number will be perplexing due to complexity of the issue and lack of data.

Apart from the above, following are some other consequences of climate change −

• Change in hydrological cycle and water supply

• The Inter-Tropical Convergence Zone (ITCZ) may move northward in the northern hemisphere causing rapid changes in rainfall pattern

• Increase in tropical and temperate cyclones, cloud cover, tornadoes and storms

• Changes in pressure belts and atmospheric circulation

• Warming of ocean water may endanger the corals worldwide

• Expansion of deserts and more desertification within deserts

• Effect on food supply and international trade of grains

• National parks, sanctuaries and biosphere reserves may be altered

• Countries such as Maldives and greater parts of Netherlands etc. may submerge under water

• Climate change is making food crops less nutritious. Rising carbon dioxide emissions lead to iron and zinc deficiencies in food crops

Population Explosion & its Pressure on Environment

Finite Resources

Most resources being finite since the very beginning and natural limit to resource generation being slow, constant rise in the number of people on the earth exerts undue pressure on world resources.

Population growth and the resultant increase in human habitations in the last couple of centuries has taken away a considerable portion of natural vegetation, cultivable lands, and above all the natural habitats of wild animals. There has been loss of biodiversity and resultant ecological imbalance in severity in the current times.

More People, More Demand, More Waste

With the advent of science and technology man’s need for comfort and luxury has multiplied many times. This has necessitated the production of a great number of goods and services in the world.

Not only the huge population (7.4 billion in 2016), but also the lifestyle, consumption patterns in modern time directly affect the environment. More people demand more resources and generate more waste. Clearly one of the challenges of a growing population is that the mere presence of so many people sharing a limited number of resources strain the environment.

Rapid Urbanization and Industrialization

Rapid urbanization and industrialization during the last century in most part of the world has not only destroyed a substantial part of natural vegetation but also forced many wild animals on the verge of extinction.

Apart from the pressure on the resources due to high growth in population, technological and scientific innovations, rapid rise in automobile population, electronic gadgets, machinery and equipment have added a great number of pollutants to the environment. As a result, environmental degradation has risen to an irrecoverable level.

Developed countries where the levels of consumption are high add more to pollution than other countries. A child born in a country, where the levels of material and energy use are high, places a greater burden on the earth's resources than a child born in a poorer country.

Nonetheless, sustainable development can be pursued more easily when population size is stabilized at a level consistent with the productive capacity of the ecosystem.

Crazy Consumerism

Consumption, although necessary for the economy, can be hazardous to the environment. Consumerism is a social and economic order that supports and encourages the acquisition of goods and services in ever increasing amounts.

Man has developed an unprecedented craze for a mushrooming number of products and services available in the world market. This has been aggravated by improved marketing strategies, alluring advertisements, and consumer-friendly services offered by companies and outlets.

Approximately 2 billion people belonging to the “consumer class” are characterized by desire for processed food, desire for bigger houses, cars, durables, etc. to maintain their desired lifestyles.

Consumerism has become more acute in developing countries such as India and China than that in developed countries due to the rise in population in the former.

Reasons for Crazy Consumerism

• Growing materialistic tendencies among the modern man

• Easy access to markets due to faster development in transport and communication

• Effective marketing and advertising strategies

• Rising income levels in most part of the world

• Globalization and liberalization

• Rapid rise in income generation ways

• Greed to possess more and more

Impact of Crazy Consumerism

Increasing consumerism has led to excessive production of goods and services, which in turn has led to enormous pressure on natural environment and natural resources. Resource depletion, environmental degradation, and pollution have become the order of the day. Mankind has reached the height of environmental pollution from where it seems very difficult to return. Race for comfort and luxury has vitiated the environment disproportionately.

Excessive demand for consumer products has created most of the current environmental imbalances and these imbalances have already caused ecological disaster in different places all over the world.

Consumerism has resulted in heaps of waste in urban and also in rural areas which lead to a pollution of environment. Mounting e-waste in the world, especially in developed countries, is causing more harm to the environment. Popularity of plastic for various purposes is adding severely to air, water, and land pollution.

Environmental Studies - Ozone Depletion

Ozone is a form of oxygen in which three atoms of oxygen combine to form a single molecule of ozone. It normally is not found in the lower atmosphere. It exists in the stratosphere between 20 and 50 kilometers above the surface.

The presence of ozone is of singular importance because it filters out the incoming ultraviolet (UV) radiation and thus acts as a screen against ultraviolent radiation that can increase the occurrence of skin cancer, cataracts, and other diseases of eyes. It also affects the body defense mechanism, which increases the vulnerability of infectious diseases.

Increased ultraviolet radiation can seriously affect plant and fish production.

Ozone Depletion

Ozone depletion refers to the wearing out or reduction of the amount of ozone in the stratosphere. It was first identified in 1970s due to the advent of supersonic aircraft, which fly in the lower stratosphere and emit nitrogen oxides.

Ozone Depleting Substances

Ozone depleting substances are those substances which deplete the ozone layer.

It is found that the major cause of ozone depletions is the CFC (Chlorofluorocarbons) gases. CFCs are used for a wide range of applications including refrigerant, foaming agents, plastic manufacturing, fire extinguishing agents, solvents for freezing food, cleaners for electronic components fine retardant, solvents, aerosol, propellants, and the production of foamed plastics.

Other ozone depleting substances controlled by Montreal Protocol (discussed in a subsequent chapter) are −

• Halon
• Carbon tetrachloride (CCl4), Methyl chloroform (CH3CCl3)
• Hydrobromofluorocarbons (HBFCs)
• Hydrochlorofluorocarbons (HCFCs)
• Methyl bromide (CH3Br)
• Bromochloromethane (CH2BrCl)

There are serious consequences of ozone depletion. Following are some of the significant consequences of ozone depletion.

• Plants and animals vary in their tolerance of ultraviolet rays. The ultraviolet rays damage DNA (the genetic code in every living being). Crops such as soybean are the worst affected.

• Animals and humans also have adapted to UVB radiation. In case of depletion of the ozone layer, there is danger of melanoma – a type of skin cancer. The disease is now almost epidemic in the United States.

Deforestration & Desertification

With exponential growth in human population and consequential destruction of natural vegetation and habitats of other living beings for urbanization, industrialization in both developed and developing countries, there is large scale deforestation in tropical and subtropical countries in the world.

Deforestation simply refers to cutting down of trees and the destruction of natural vegetation in an aggressive way.

Factors Responsible for Deforestation

The following factors are responsible for deforestation −

• Rapid growth of population in the developing countries.

• Extension of agriculture and grazing land.

• Increasing demand for lumber, timber, paper, pulp, fuel-wood, and charcoal and other forest produce.

• Industrialization, urbanization, and consumerism in the developed and developing countries.

• Demand of raw material for forest-based and agro-based industries.

• Demand of land for infrastructure such as roads, highways, railways, irrigation, electricity, telecommunication services, and civic facilities.

• Construction of multi-purpose dams all over the world.

• Practice of shifting cultivation in the humid-tropical regions of the world.

• Change in food habits – a visible shift from vegetarian food to non-vegetarian food.

• High rate of poverty in the third world countries; it is said that poverty directly or indirectly lead to deforestation.

• Both natural and man-made forest fire.

• Delayed administrative decision and dilatory implementation of forest laws in developing countries.

Desertification

Desertification is defined by the UN Convention to Combat Desertification (CCD) 1995 as land degradation in arid, semi-arid, and dry-sub-humid areas resulting from various factors including climate variation and human activities.

The problem of desertification is common to the susceptible dry-lands, with land degradation such as soil erosion, internal soil changes, depletion of groundwater reserves, and irreversible changes to vegetation communities.

The term desertification was coined by the French botanist, Aubreville, in 1949 to describe land degradation. Desertification is more anthropogenic (man-made) than it is natural. It is well-acknowledged that the principal agent of land degradation is human activities.

The tropical and sub-tropical lands are more prone to desertification. An estimate made by the United Nations (UN), about 40 percent of the African continent’s non-desert land is in danger of experiencing desertification. About 33 percent of Asia’s land and about 20 percent of Latin America land area are equally threatened with desertification.

Countries with extensive and severe desertification are Jordan, Lebanon, Somalia, Ethiopia, Southern Sudan, Chad, Mali, Mauritania, and Western Sahara.

International Protocols

Without a healthy and clean environment, human beings will be deprived of their right to a healthy and productive life. We have learnt substantially how environmental pollution is taking away our rights to such life. So, to keep the biodiversity and environment in a healthy condition is the need of the hour.

Environment and more specifically environmental pollution has no political boundaries. The air polluted in one region can be transmitted to thousands of miles without the manmade barriers. Thus, environmental pollution, global warming, climate change and other related issues have been given more weight at international forums and symposia.

A number of efforts are being made at international and national levels to maintain the equilibrium and resilience characteristics of the ecosystems with the objective to make them sustainable and productive. These efforts are given the nomenclature of international conventions or conferences and protocols.

What are Conventions and Protocols?

A convention is a meeting or gathering to formulate or deliberate on a generally accepted principle, framework in which the parties decide the basic guidelines. For example, Rio Convention.

A protocol, on the other hand, contains specific aims or legal obligations agreed upon by the members who gather in a convention or conference. Usually, when a major provision is to be incorporated on regulations of the convention, a protocol is called among the countries, who are signatory of the original convention when it was signed and approved.

The United Nation’s Framework Convention on Climate Change

The United Nations Framework Convention on Climate Change (UNFCCC or FCCC) is an international environmental treaty created at the United Nations Conference on Environment and Development (UNCED), informally known as the Earth Summit, held in Rio de Janeiro from June 3 to 14, 1992.

The United Nations Climate Change Conferences are annual events held in the framework of UNFCCC. The conferences are held to assess the progress made in efforts to deal with climate change.

These conferences serve as the formal meeting of the UNFCCC Parties and are popularly called Conference of Parties (COP). Palestine became the 197th party to UNFCCC in 2016.

The first UN Climate Change Conference or Conference of Parties (COP 1) was held in 1995 in Berlin.

Landmark Conferences of Parties (COPs)
Year	Name of the COP	Focal Point
2007	COP 13 – Bali Action Plan	To further commitments by parties to Kyoto Protocol
2009	COP 15 – Copenhagen Accord	To establish an ambitious global climate agreement for the period from 2012, when the first commitment period under the Kyoto Protocol expires
2010	COP – 16 – Cancun Agreement	Encompassed finance, technology, and capacitybuilding support to help such countries meet urgent needs to adapt to climate change; Set up Green Climate Fund to support climate change mitigation efforts
2011	COP – 17 – Durban Agreement	To adopt a universal legal agreement on climate change as soon as possible, and no later than 2015
2016	COP – 22 – Marrakesh Action Proclamation	Pledge to press ahead with implementation of Paris Agreement

Objectives of UNFCCC

• To stabilize Greenhouse Gas concentration to such a level that would prevent human induced interference with the climate system within a timeframe.

• To enable the ecosystems to adapt naturally to climate change to ensure that food production is not threatened and to enable economic development to proceed in a sustainable manner.

Earth Summit

The Brundtland Report of 1987 sent an alert to the world about the urgency of making progress towards sustainable economic development without harming the already sick environment and without depleting the vanishing natural resources.

Five years later, the progress on enunciated sustainable development was sought by the UN and United Nations Conference on Environment & Development. Held in June 1992 at Rio de Janeiro in Brazil, the Rio Earth Summit as it became popularly known, was the largest environmental conference ever held, attracting over 30,000 people including more than 100 heads of state.

The Rio Conference was held primarily with an objective towards building upon the hopes and achievements of the Brundtland Report with a view to responding to mounting global environmental problems and to agree on major treaties on biodiversity, climate change, and forest management.

The major outcome of the Earth Summit was Agenda 21. Agenda 21 is a comprehensive plan of action to be taken globally, nationally, and locally by organizations of the United Nations System, Governments, and Major Groups in every area that humans impact on the environment.

Besides, the Rio Declaration on Environment and Development, and the Statement of Principles for the Sustainable Management of Forests were adopted.

The Earth Summit influenced all subsequent UN conferences, which have examined the relationship between human rights, population, social development, women and human settlements — and the need for environmentally sustainable development.

The Kyoto Protocol

In order to reduce the growing concentration of greenhouse gases (GHGs) in the Earth’s atmosphere, the UNFCCC put in place the first ever agreement between nations to mandate country-by-country reduction in GHGs. This historic Protocol was adopted in Kyoto, Japan, on 11 December 1997 and hence, got the name of Kyoto Protocol.

The Kyoto Protocol officially came into force in 2005, after being formally ratified by the required number of nations. Participating nations or the signatories have agreed to meet certain greenhouse gas emission targets, as well as submit to external review and enforcement of these commitments by the UN-based bodies.

The parties or the signatory countries committed to reduce the GHGs emission, based on the premise that (a) global warming exists and (b) man-made CO2 emissions have caused it.

Under Kyoto, industrialized nations pledged to cut their yearly emissions of carbon, as measured in six greenhouse gases, by varying amounts, averaging 5.2%, by 2012 as compared to 1990.

It excluded developing countries such as China and India, which have since become the world's largest and fourth largest polluters according to the International Energy Agency, as well as second-placed United States which refused to ratify the deal.

A second commitment period was agreed on in 2012, known as the Doha Amendment to the protocol, in which 37 countries have binding targets: Australia, the European Union (and its 28 member states), Belarus, Iceland, Kazakhstan, Liechtenstein, Norway, Switzerland, and Ukraine.

Initiatives like Kyoto Protocol has been necessitated as the UN has set a target of limiting global warming to 2.0 degrees Celsius (3.6 Fahrenheit) from pre-industrial levels — a level at which scientists say the planet may be spared the worst impacts of climate change.

Montreal Protocol

The Montreal Protocol is related to the substance that depletes the ozone layer of the atmosphere. This International Treaty, is designed to protect the ozone layer, by phasing out the production of numerous substances believed to be responsible for ozone depletion. The Treaty was opened for signature on 16 September, 1987 and came into force on 1 January, 1989.

Its first meeting was held at Helsinki in May, 1989. Since then, it has undergone several revisions in London (1990), Nairobi (1991), Copenhagen (1992), Bangkok (1993), Vienna (1995), Montreal (1997, Beijing (1999), and Kigali (2016).

It was agreed that if this international agreement is strictly adhered to, the ozone layer would recover by 2005. At first, the aim was to remove harmful chemicals such as CFCs by 50 percent by 1998. The target was further revised so as to curtail the production of these chemical at the earliest.

The Montreal Protocol has been ratified by 196 countries. It is the first international treaty to achieve complete ratification by member countries. In Kigali, Rwanda in 2016, the Parties (Members) agreed to an international phase down of 85 percent of Hydroflurocarbons (HFCs).

Paris Agreement

The Paris Agreement or Paris Climate Agreement is a UN sponsored pact to bring the world countries together in the fight against climate change.

Countries that sign on to be a part of the pact agreed to limit the century’s global average temperature increase to no more than 2 degrees Celsius (3.6 degrees Fahrenheit) above the levels from the years 1850-1900 (the pre-industrial era) and to pursue efforts to limit the temperature increase even further to 1.5 degrees Celsius.

Participating countries made the Paris Pact on 12 December, 2015 to adopt green energy sources, cut down on greenhouse gas emission, and limit the rise of global temperature.

Every country has an individual plan or ‘Nationally Determined Contributions’ to tackle greenhouse gas emission.

The agreement went into effect on Nov. 4, 2016; 30 days after at least 55 countries representing at least 55 percent of the world’s global emissions ratified it on Oct. 5, 2016. As of May 2017, of the 196 negotiating countries that signed the agreement, 147 parties have ratified it.

Policy and Legislation

In the previous chapters, we have learnt about the environment, ecosystem, natural resources, biodiversity and its importance for the living world, especially for mankind. We have also learnt how environmental problems such as pollution and climate change affect and threaten our survival. There is a need for knowing the legal and constitutional provisions for protecting and nurturing the nature. In this chapter, we will learn about such provisions and acts.

Need for Policy & Legislation

It has always been the desire of man to have clean air, clean water and environment free of toxins and pollutants. In the first half of the last century, there were few legal and constitutional mechanisms in place to protect the environment and the natural resources found in a country.

Increasing pollution and mounting pressure on air, water and land quality led to environmental legislations being designed to protect the environment from harmful actions. Due to the current state of the environment, policy makers in every country need to place a top priority on environmental policy.

Natural resources, both renewable and non-renewable and wildlife are continuously being under threat. It is estimated that considering the present rate of exploitation of such resources we are going to be devoid of many important resources in near future. Unless we take care of them and resort to a sustainable use, we will make our posterity live without resources. Hence, there is a need for environmental policies and legislations.

What is an Environmental Policy?

Policy refers to a set of principles or plans agreed upon by a government or an organization to be carried out in a particular situation. Environmental policy is defined as “any action deliberately taken to manage human activities with a view to prevent, reduce, or mitigate harmful effects on nature and natural resources, and to ensure that man-made changes to the environment do not have harmful effects on human or the environment”.

Environmental policy usually covers air and water pollution, waste management, ecosystem management, biodiversity protection, and the protection of natural resources, wildlife and endangered species. Proper policies and legislations at the national and the international levels can reduce the venomous pollution and help protect biodiversity and natural resources.

What is an Environmental Legislation?

Environmental legislation is a set of laws and regulations which aim at protecting the environment from harmful actions.

Legislation may take many forms, including regulation of emissions that may lead to environmental pollution, taxation of environment- and health-damaging activities, and establishing the legal framework for trading schemes, for example, carbon emissions. Other actions may rely on voluntary agreements. Among major current legislative frameworks are those relating to environmental permitting, and those mandating environment and health impact assessments.

Environmental Protection Act

Most of the countries in the world have enacted Environmental Protection Acts considering the need for the protection of our environment.

In the US, the National Environmental Policy Act (NEPA) of 1970 promotes the enhancement of the environment and established the President’s Council on Environmental Quality (CEQ). It is referred to as the ‘environmental Magna Carta’ in the USA because it was an early step towards the development of US’ environmental policy. Other environmental acts in the USA are as follows.

• Clean Air Act of 1970 and 1990
• Clean Water Act of 1972
• Endangered Species Act of 1973
• Resource Conservation and Recovery Act of 1976
• National Forest Management Act of 1976
• Surface Mining Control and Reclamation Act of 1977
• Comprehensive Environmental Response, Compensation and Liability Act of 1980

Environmental Protection Acts in India

In the Constitution of India, it is clearly stated that it is the duty of the state to ‘protect and improve the environment and to safeguard the forests and wildlife of the country’. It imposes a duty on every citizen ‘to protect and improve the natural environment including forests, lakes, rivers, and wildlife’.

There are a number of environmental acts enacted in India. Some of the important legislations in this respect are −

• Wildlife Protection Act, 1972
• Forest (Conservation) Act, 1980
• Water (Prevention and Control of Pollution) Act, 1974
• The Air (Prevention and Control of Pollution) Act, 1981
• Environmental Protection Act, 1986
• Handling and Management of Hazardous Waste Rules, 1989
• The National Environmental Tribunal Act, 1995
• The Biological Diversity Act, 2002

Environmental Protection Act, 1986

Environmental Protection Act, 1986, was a statutory response that came into effect a year after the tragic Bhopal Gas Tragedy and is considered an umbrella legislation as it addresses many loopholes in the existing environmental laws. It was enacted as per the spirit of the Stockholm Conference held in June 1972 to take suitable measures for the protection and reinvigoration of environment and related matters.

The Environment (Protection) Act is applicable to whole of India including Jammu & Kashmir. It came into force on November 19, 1986. EPA 1986 was enacted largely to implement the decisions made at the UN Conference on Human Environment held at Stockholm in June, 1972.

It was to co-ordinate the activities of the various regulatory agencies under the existing laws. It also seeks collection and dissemination of information on environmental pollution.

A lot have been done to protect and improve the environment world over. However much remains to be done for building a sustainable society. New mechanisms are being put in place to expedite the process of protecting and improving the environment. For example, new institutions — the National Environment Management Authority (NEMA) and the State Environment Management Authorities (SEMA) — in India have been proposed as full-time technical organizations with the capacity to process all environmental clearance applications in a time-bound manner.

Air, Water & Forest Acts

Environment constitutes air, water, land, or vegetation. To protect the environment means to take constructive measures to free these natural objects from pollutants. The measures are backed by the constitution and the chief law making forum in a country so as to ensure an expedited and assured implementation of the measures. An Act provides for the prevention, control and abatement of air pollution, water pollution, and forest degradation.

For instance, a number of acts have been enacted to protect and improve air, water and forest in India.

Acts Related to Air Pollution

The Factories Act and Amendment, 1948 was the first to express concern for the working environment of the workers. The amendment of 1987 has sharpened its environmental focus and expanded its application to hazardous processes.

The Air (Prevention and Control of Pollution) Act, 1981 provides for the control and abatement of air pollution. It entrusts the power of enforcing this act to the Central Pollution Control Board (CPCB).

The Air (Prevention and Control of Pollution) Rules, 1982 defines the procedures of the meetings of the Boards and the powers entrusted to them.

The Atomic Energy Act, 1982 deals with radioactive waste.

The Air (Prevention and Control of Pollution) Amendment Act, 1987 empowers the central and state pollution control boards to meet with grave emergencies of air pollution.

The Motor Vehicles Act, 1988 states that all hazardous waste is to be properly packaged, labeled, and transported.

Acts Related to Water Pollution

The Indian Fisheries Act, 1897 establishes two sets of penal offences whereby the government can sue any person who uses dynamite or other explosive substance in any way (whether coastal or inland) with the intent to catch or destroy any fish, or poisonous fish in order to kill.

The River Boards Act, 1956 enables the states to enroll the central government in setting up an Advisory River Board to resolve issues in inter-state cooperation.

The Merchant Shipping Act, 1970 aims to deal with waste arising from ships along the coastal areas within a specified radius.

The Water (Prevention and Control of Pollution) Act, 1974 establishes an institutional structure for preventing and abating water pollution. It establishes standards for water quality and effluent. Polluting industries must seek permission to discharge waste into effluent bodies. The CPCB (Central Pollution Control Board) was constituted under this Act.

The Water (Prevention and Control of Pollution) Cess Act, 1977 provides for the levy and collection of cess or fees on water consuming industries and local authorities.

The Water (Prevention and Control of Pollution) Cess Rules, 1978 contains the standard definitions and indicates the kind of and location of meters that every consumer of water is required to affix.

The Coastal Regulation Zone, 1991 Notification puts regulations on various activities, including construction. It gives some protection to the backwaters and estuaries.

Acts Related to Forests

The Indian Forest Act and Amendment, 1984 is one of the many surviving colonial statutes. It was enacted to ‘consolidate the law related to forest, the transit of forest produce, and the duty to be levied on timber and other forest produce’.

The Wildlife Protection Act and Rules, 1973 and Amendment 1991 provides for the protection of birds and animals and for all matters that are connected to it, whether it be their habitat or the waterhole or the forests that sustain them.

The Forest (Conservation) Act and Rules, 1981, provides for the protection of and the conservation of the forests.

The Biological Diversity Act, 2002 is an act to provide for the conservation of biological diversity, sustainable use of its components, and fair and equitable sharing of the benefits arising out of the use of biological resources and knowledge associated with it.

Environmental Impact Assessment

The effects of human activities related to the use of environmental resources on natural environment is called Environmental Impact. The assessment and evaluation of environmental effects of human activities are collectively called Environmental Impact Assessment (EIA).

Environmental Impact Assessment is, therefore, a method of evaluating environmental consequences such as environmental changes which are likely to be caused by the proposed human activities related to land use changes, construction of dams, reservoirs, roads, rails, bridges, industrial locations, urban expansion, etc. and the possible adverse effects of these environmental changes.

Environmental changes mean environmental degradation and pollution resulting into ecological imbalance and ecosystem disequilibrium. The environmental impact assessment process began with the enactment of the National Environmental Policy Act (NEPA) in the US in 1969.

Objectives of Environmental Impact Assessment

In view of the colossal damage to the environment, there is a felt need for assessing the environmental impacts of developmental activities. EIA is a tool to anticipate the possible damage to the environment caused by developmental projects and schemes, and propose mitigation measures and strategies.

EIA exerts to declare a national policy to encourage productive and enjoyable harmony between man and environment. It promotes efforts to prevent or eliminate damage to the environment and the biosphere, and stimulate the health and welfare of man.

It seeks to increase the understanding of ecological system and nature resources important to the nation and to provide for appropriate institutional structure to carry out the objectives.

It provides a broad, integrated perspective of a region about to undergo or undergoing developments. EIA ascertains the cumulative impacts from the multiple development in the region. It establishes priorities for environmental protection. It also identifies the positive and negative aspects of any project as well as assesses the policy options and analyzes the impact on the environment therein.

Projects that Require Environmental Clearance

• Manufacturing Industries
• Mining
• Thermal Power Plants
• River Valley Projects
• Infrastructure and Coastal Regulation Zone
• Nuclear Power Projects

Steps in Environmental Impact Assessment

• Describe the present environment
• Describe the project, including purposes and needs
• Describe the effects of the project
• Describe the impact, both short term and long term
• Suggest and compare alternatives (projects)
• Suggest mitigating activities or remedial measures

Towards Sustainable Future

According to the United Nations, "Sustainable development is the development that meets the needs of the present without compromising the ability of future generations to meet their own needs." Sustainable development requires meeting the basic needs of all and aims to provide all the opportunity to meet their aspirations to lead a better and healthy life.

Concept of Sustainable Development

Our living standards should be in tune with the limit of the world’s ecological means. However, many of us live beyond it and have scant regard for long-term sustainability. Economic growth and development is required to be in commensurate with the limits of the ecology and environment. It is required largely by the sustainable development.

Sustainable development requires setting limits in terms of population or resource use beyond which lies ecological disaster. It warns every one of us against surpassing the ultimate limits of the natural system, or else face dire consequences. It also requires that long before mankind crosses these limits, the world must ensure equitable access to the constrained resource and use technology towards it.

Economic growth and development obviously involve changes in the physical ecosystem. However, it should not cross the limits of regeneration and natural growth. For instance, renewable resources such as forests and fish stocks need not be depleted provided the rate of use is within the limits of regeneration and natural growth.

Sustainable development requires that the rate of depletion of non-renewable resources should foreclose as few future options as possible. It requires flourishing biodiversity and,hence, it vouches for the conservation of plant and animal species. It also vouches for a type of development where the adverse impacts on the quality of air, water, and other natural elements are minimized so as to sustain the ecosystem’s overall integrity.

Sustainable development is a wholesome process of change in which the use of resources, investment, the orientation of technological development and institutional changes are all in harmony with and enhance both the current and future potential to meet human needs and aspirations.

17 New UN Development Goals for 2030

• End poverty in all its forms everywhere

• End hunger, achieve food security and improved nutrition, and promote sustainable agriculture

• Ensure healthy lives and promote well-being for all at all ages

• Ensure inclusive and equitable quality education and promote lifelong learning opportunities for all

• Achieve gender equality and empower all women and girls

• Ensure availability and sustainable management of water and sanitation for all

• Ensure access to affordable, reliable, sustainable and modern energy for all

• Promote inclusive and sustainable economic growth, full and productive employment, and decent work for all

• Build resilient infrastructure, promote inclusive and sustainable industrialization, and foster innovation

• Reduce inequality within and among countries

• Make cities and human settlements inclusive, safe, resilient, and sustainable

• Ensure sustainable consumption and production patterns

• Take urgent action to combat climate change and its impact

• Conserve and sustainably use the oceans, seas, and marine resources for sustainable development

• Protect, restore, and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, halt and reverse land degradation, and halt biodiversity loss

• Promote peaceful and inclusive societies for sustainable development, provide access to justice for all and build effective, accountable, and inclusive institutions at all levels

• Strengthen the means of implementation and revitalize the global partnership for sustainable development

The new goals replace the eight Millennium Development Goals adopted at a Summit in 2000, which expired at the end of 2015.

Environmental Education

Environmental education is a multi-disciplinary field integrating disciplines such as biology, chemistry, physics, ecology, earth science, atmospheric science, mathematics, and geography.

Environmental Education (EE) aims at increasing the consciousness and knowledge about the various aspects of environment and also about the major environmental problems facing the world today. It also spreads awareness among the masses with special emphasis on educators, voluntary works, youth and women with a view to promote conservation of nature and its resources.

It develops and makes room for implementation of innovative, region-specific educational programs and materials for conservation education and sensitizes children on environment. It includes all efforts to make general public aware of the knowledge of the environmental challenges through media and print materials.

UNESCO (United Nation Educational, Scientific, and Cultural Organization) emphasizes the role of EE in safeguarding future global developments of societal quality of life (QOL), through the protection of the environment, eradication of poverty, minimization of inequalities, and insurance of sustainable development.

Today, environmental education has become one of the most popular academic study world-over. There are special institutions coming up in the world to impart higher degrees on environmental education.

Life Cycle Assessment

Life Cycle Assessment (LCA) is a tool used to assess the potential environmental impact of product systems or services at all stages in their life cycles, i.e. from the extraction of raw materials, manufacturing or processing, storage, distribution, use and its disposal or recycling.

In other words, LCA is a technique for assessing the potential environmental and other aspects associated with a product or a service by various methods such as −

• Compilation of an inventory of inputs and outputs

• Evaluation of potential environmental impact relating to those inputs and outputs

• Interpretation of the results of the evaluation

LCA is, therefore, a cradle-to-grave assessment of production system and their likely environmental impacts. It has come up as a valuable decision-support tool for both policy makers and industry in assessing from origin-to-end impact of a product or process.

LCA methodology has been developed extensively during the last decade. Moreover, a number of LCA related standards (ISO 14040-14043) and technical reports have been published within the International Organization for Standardization (ISO) to streamline the methodology.

Following is the representation of the LCA process.

The overall objective of LCA is to identify changes, at every stage of the life cycle of a product or process that can be helpful to the environment and prove to be cost effective.

Low Carbon Lifestyle

Carbon dioxide (CO₂) is a vital constituent in the Earth’s atmosphere. It is a major greenhouse gas and plays a vital role in regulating the Earth’s surface temperature. Carbon dioxide is an integral part of the carbon cycle, which is a biogeochemical cycle in which carbon is exchanged between the earth's oceans, soil, rocks, and the biosphere.

Carbon content in dry air is around 0.01 percent. When such percentage is increased largely by anthropogenic or man-made activities, the air gets polluted. CO₂ is one the prominent greenhouse gases that has been adding to the severity of atmospheric pollution and global warming in recent times.

Human activities such as increasing automobile population, industries, and consumption of electricity, etc. emit great amount of carbon into the atmosphere. For mankind’s extensive dependence on natural resources and its mindless exploitation, has been slowly but steadily withering the green cover from the earth.

Carbon footprint is the amount of carbon dioxide released into the atmosphere as a result of the activities of a particular individual, organization, or community. At an individual level, these greenhouse gases are generated through transport, production and consumption of food, fuels, manufactured goods and other services.

Steps to Maintain Low Carbon Lifestyle

• De-carbon Life − Switching to a lifestyle which has the least possible impact on the environment, generates the smallest carbon footprint. Everything an individual, organization, business or government does or uses embodies some form of carbon. These should be chosen based on the least amount of impact they will have on the climate and the environment.

• Get Energy Efficient − Improving the efficiency of your buildings, computers, cars, and products is the fastest and most lucrative way to save money, energy and carbon emissions. High performance, environmentally accountable, energy efficient and productive facilities are now economically possible. For instance, use of LED bulbs in place of incandescent bulbs is a case in point.

• Switch to Low Carbon Energy − We should make an effort to get energy from renewable sources such as solar or wind energy. Shifting from conventional sources to nonconventional energy sources to the best extent possible will have a visible impact on the environment. Today, more than 50 per cent of all US consumers, for example, have an option to purchase some type of green power product.

• Switch to Low Carbon Products and Services − The market for climate-friendly products and services is growing rapidly, from energy-efficient products to new renewable energy systems. Eco-Design is an important strategy for small and medium sized companies both in developed and developing countries to improve the environmental performance of their products, reduce waste, and improve their competitive position in the market.

• Buy Green and Sell Green − Today, there is a growing number of consumers willing to buy green products, if given the choice.

  To realize or make incessant efforts to achieve a sustainable world lies in the hands of man. Mankind, if desires, can deactivate the destructive processes that have so crippled the natural environment through dedicated and well-planned actions and initiatives. Failure to do so endangers civilization and paves the way for mass suffering, conflicts, and multiple collapses all around us.