Multidisciplinary nature of Environmental Science

Multidisciplinary nature of Environmental Science
Environmental Science is a multidisciplinary science because it comprises of various branches of studies such as chemistry, physics, medical science, life science, agriculture, public health, sanitary engineering, etc. It is the science of physical phenomena in the environment. It educates individuals from various walks of life about the delicate balance of nature and the recklessness with which we are damaging this environment thereby endangering our very existence. This has been illustrated in real life in the past and continues through the present age. Environment science is a study of the sources, reactions, transport, effect and fate of human activities on biological species in air, water and soil. An understanding of the working of the environment require knowledge from wide ranging fields. The multidisciplinary nature of environmental science with respect to air pollution is shown in the table below:

Environmental issue / topic                                                 Major Subject

Nature and reaction of air pollutants                                          Chemistry and chemical engineering
Effects of air pollution on humans, animals and plants                  Zoology, Botany, and various branches of                                                                                                    life science, physics and chemistry
Effects of air pollutants on materials                                           Chemistry and chemical engineering
Effects of air pollution on climate                                                Mathematical modelling
Air pollution control devices                                                       Physics, Chemistry and various branches of                                                                                                  engineering
Economic effects of Air pollution                                                Economics, Demography
Conservation of resources and pollution control                          Various branches of physical and political                                                                                                     science
Alternative fuels                                                                          Various branches of physical science.

Environmental Science - The need for public awareness

It is essential to make the public aware of the formidable consequences of the Environmental Degradation. If these are not addresses and reformative measures undertaken, the extinction of life is inevitable. We are facing various environmental challenges as discussed below:

• Growing Population A population of over thousands of millions is growing. Over 17 million people are added each year. It puts considerable pressure on its natural resources and reduces the gains of development. Hence, the greatest challenge before us is to limit the population growth. Although population control does automatically lead to development, yet the development leads to a decrease in population growth rates. 

• Poverty India has often been described a rich land with poor people. Poverty and environmental degradation have a nexus between them. The vast majority of our people are directly dependent on the natural resources of the country for their basic needs of food, fuel, shelter and fodder. 
• Environment degradation has adversely affected the poor who depend upon the resources of their immediate surroundings. Thus, the challenge of poverty and the challenge of environment degradation are two facets of the same challenge. 
• Population growth is essentially a function of poverty. Because, to the very poor, every child is an earner and helper and global concerns have little relevance for him.
• Agricultural Growth People must be acquainted with the methods to sustain and increase agricultural growth without damaging the environment. High yielding varieties have cause soil salinity and damage to physical structure of soil.
• Need for Ground water It is essential to rationalize the use of groundwater. Factors like community wastes, industrial effluents and chemical fertilizers and pesticides have polluted our surface water and affected quality of the groundwater. It is essential to restore the water quality of our rivers and other water bodies as lakes. Deciding on suitable technologies for restoring the quality of groundwater aquifers is essential.
• Development And Forests Forests serve catchments for the rivers. The increasing demand of water, led to using rivers for irrigation projects. These caused forests to submerge and displacement of local people apart from damaging the local flora and fauna. 
• Forests in India have been shrinking for several centuries owing to pressures of agriculture and other uses. Vast areas that were once green, stand today as wastelands. These areas are to be brought back under vegetative cover. The tribal communities inhabiting forests respects the trees and birds and animal that gives them sustenance. We must recognize the role of these people in restoring and conserving forests. 
• The modern knowledge and skills of the forest department should be integrated with the traditional knowledge and experience of the local communities. The strategies for the joint management of forests should be evolved in a well planned way.
• Degradation of land A small portion of land possesses potential for production. Agricultural land suffers from varying degrees of soil degradation. Land degradation mainly occurs due to overgrazing and soil erosion due to wind and water.
• Reduction of Genetic Diversity Proper measures to conserve genetic diversity need to be taken. At present most wild genetic stocks have been disappearing from nature. Wild animals including the Asiatic Lion are facing problem of loss of genetic diversity. The protected areas network like sanctuaries, national parks, biosphere reserves are isolating populations. So, they are decreasing chances of one group breeding with another. Remedial steps are to be taken to check decreasing genetic diversity.
• Evil Consequences of Urbanisation Nearly 27 per cent Indians live in urban areas. Urbanisation and industrialisation has given birth to a great number of environmental problem that need urgent attention. Over 30 percent of urban Indians live in slums. Out of India’s 3,245 towns and cities, only 21 have partial or full sewerage and treatment facilities. Hence, coping with rapid urbanization is a major challenge.
• Air and water Pollution: Majority of our industrial plants are using outdated and population technologies and makeshift facilities devoid of any provision of treating their wastes. A great number of cities and industrial areas that have been identified as the worst in terms of air and water pollution. Acts are enforced in the country, but their implementation is not easy. The reason is their implementation needs great resources, technical expertise, political and social will. Again the people are to be made aware of these rules. Their support is indispensable to implement these rules.

SCOPE OF THE ENVIRONMENT

SCOPE OF THE ENVIRONMENT

The environment consists of four segments.
Atmosphere:
This is the protective blanket of gasses surrounding the earth.
It sustains life on earth
It saves the earth from the hostile environment of outer space
It absorbs most of the cosmic rays from outer space and a major portion of the electromagnetic radiation from the sun
It transmits only the near UV, visible and near IR (300 - 2500 nm)and radio waves (0.4 - 40 m) waves
It filters-out damaging UV waves wave length less than 300 nm.

The oxygen is composed of Nitrogen and Oxygen besides Argon, CO2 and trace gases.

Hydrosphere: The hydrosphere comprises of all types of water resources (oceans, seas, rivers, streams, reservoirs, polar icecaps, glaciers and ground water). Almost 97% of earths water supply is in the oceans. More than 2% of water resources is locked in polar ice caps. The remaining water (less than 1%)is available as fresh water in the form of rivers, streams, lakes and ground water. It is this meagre amount that is fit for human consumption.

Lithosphere: Lithosphere is the outer mantle of solid earth. It consists of minerals occurring in the earth's crust and the soil.

Biosphere: Biosphere indicates the realm of living organisms and their interaction with the environment (Atmosphere, Hydrosphere and Biosphere)

Four basic principles of ecology

The four basic principles of ecology are:
(i) Holism
(ii) Ecosystem
(iii) Succession
(iv) Conversation.
Holism has been considered as the real base of ecology. 

Importance of Environmental Science

Environment science enlightens us, about the importance of protection and conservation of our indiscriminate release of pollution into the environment. Environmental issues have grown in size and complexity
day by day, threatening the survival of mankind on earth. We study about these issues besides suggesting effective solutions to these problems.

Environment Issues Being of International Importance
It has been recognized that environment issues like global warming, ozone depletion, acid rain, marine pollution and biodiversity are not merely national issues but are global issues and hence must be tackled with international efforts and cooperation.

Problems Cropped in The Wake of Development
Development, in its wake gave birth to Urbanization, Industrial Growth, Transportation Systems, Agriculture and Housing etc. When the West developed, it ignored of the environmental impact of its activities. Such a path is neither practicable nor desirable.

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

 Need for An Alternative Solution
It is essential, for developing countries to find alternative paths. A goal needs to be developed as described below:

• A goal, which ultimately is the true goal of development an environmentally sound and sustainable development.
• A goal common to all citizens of our earth.
• A goal to prevent the developing world from the over-consuming wasteful activities of the “developed” world.

Need To Save Humanity From Extinction

It is necessary for us to save the humanity from extinction. Consequent to our activities constricting the environment and depleting the biosphere, in the name of development.

Need For Wise Planning of Development

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

Environmental Science - Introduction

The word environment is derived from the French word “environner” which means to encircle or surround. Thus our environment can be defined as the physical, chemical and biological world that surround us and the complex social and cultural conditions affecting an individual or community.

This broad definition includes the natural world and the technological environment as well as the cultural and social contexts that shape human lives. It includes all factors living and nonliving that affect an 

individual organism or population at any point in the life cycle.

The three reasons for studying the state of the environment are listed below.

• There is a need for information that clarifies modern environmental concepts like equitable use of natural resources and a sustainable life style.
• There is a need to change the way in which we view our environment, using practical approach based on observation and self learning.
• There is a need to create a concern for our environment that will trigger pro-environmental action including simple activities we can do in our daily life to protect it.

Environmental science is essentially the application of scientific methods and principles to the study of environmental issues. It is a multidisciplinary subject and its components include Biology, Geology, Chemistry, Physics, Engineering, Sociology, Health Sciences, Anthropology, Economics, Statistics and Philosophy. An Understanding of the working of the environment requires the knowledge from wide ranging fields. Environment is not a single subject, it is an integration of several subjects that include both science and social studies.

Thus, the scope of environmental science is extremely wide and covers some aspects of nearly every major discipline. 

ENERGY FLOW IN AN ECOSYSTEM

ENERGY FLOW IN AN ECOSYSTEM

Energy is the capacity to do work. Energy that runs ecosystems ultimately comes from the sun. Green plants trap solar energy through photosynthesis; convert it into chemical energy and store it in the form of chemical energy. The conservation and expenditure of energy is described by the two laws of thermodynamics. The first law states that energy can neither be created nor destroyed but only be converted from one form to another and the other law states that when energy is converted, there is a loss of energy in the form of heat.

In an ecosystem when the energy is transferred from one trophic level to the other, only a part of it is utilized and the rest is wasted or dissipated (in accordance with the second law of thermodynamics).

The energy production in the ecosystem is categorized into primary production and secondary production.

Primary production: Green plants are capable of fixing only 1.5% of the solar energy reaching the earth. This level is called primary trophic level. The plant tissues convert this solar (radiant) energy to chemical energy.

6CO2     +             6H2O                     hυ                           C6H12O6              +             6O2

Only a part of this chemical energy is utilized by plants for their metabolic activities and the rest is taken up by heterotrophs or consumers belonging to the next trophic level. As a result the energy is transferred from one trophic level to the second trophic level.

The glucose produced in the plant cell is either stored in the form of starch or combined with other sugar molecules forming specialized carbohydrates like cellulose. It may also combine with Nitrogen, Phosphorus and Sulfur which help in synthesis of complex molecules like proteins, nucleic acids, pigments and hormones. All these are necessary for the normal growth of the plant, maintenance of body tissues and carrying out various physiological activities. Carbohydrates are oxidized to give Carbondioxide, water and chemical energy.

C6H12O6              +             6O2                                       6CO2     +             6H2O     +             Energy

The total amount of energy converted into sugar by a plant (by photosynthesis) is called ‘Gross primary production’ or ‘Gross productivity’. Some of this energy is lost through respiration and when it is deducted from gross primary production the remaining energy is known as ‘Net primary production’

Secondary production: In an ecosystem, the potential energy derived from the primary production meets the energy demands of the other trophic levels. Some of the primary production is consumed by herbivores and omnivores in the form of food. These consumers are in-turn eaten by carnivores of higher trophic levels. No animal can digest or assimilate all the food it has eaten. For example, a herbivore can assimilate only 10% of the food it ingests and in the case of carnivores it may go up to 20%. The energy thus assimilated is retained in the body of consumers in different forms. The food that cannot be digested leaves the animal bodies as feces which is an important source of energy for detritus feeders and saprotrophs.

A part of the energy assimilated by the herbivores is utilized in various metabolic activities like respiration, excretion, secretion, locomotion and reproduction. The remaining is stored in their tissues. This energy is called ‘Net secondary production’. The ‘Gross secondary production’ is equivalent to the total plant material ingested by herbivores minus the matter lost as feces.

The energy flow through different stages of an ecosystem occurs as shown below:

Solar energy                       Producers                           Primary consumers                         Secondary consumers  

                                                (Green Plants)                  (Herbivores)                                      (Primary carnivores)

 

Tertiary consumers

(Secondary carnivores)

Environmental Studies Syllabus (Osmania University)

UNIT I
Environmental studies: Definition, scope and importance, need for public awareness. Natural
resources: Water resources; use and over utilization of surface and ground water, floods,
drought, conflicts over water, dams - benefits and problems. Effects of modem agriculture,
fertilizer-pesticide problems, water logging salinity. Energy resources, growing energy needs,
renewable and nonrenewable energy sources. Land Resources, land as a resource, land
degradation, soil erosion and desertification.

UNIT II
Ecosystems: Concepts of an ecosystem, structure and functions of an ecosystem, producers,
consumers and decomposers, energy flow in ecosystem, food chains, ecological pyramids,
aquatic ecosystem (ponds, streams, lakes, rivers, oceans, estuaries).

UNITIII
Biodiversity: Genetic species and ecosystem diversity, bio-geographical classification of India.
Value of biodiversity, threats to biodiversity, endangered and endemic species of India,
conservation of biodiversity.

UNIT IV
Environmental Pollution: Causes, effects and control measures of air pollution, water
pollution, soil pollution, noise pollution, thermal pollution and solid waste management.
Environment Protection Act: Air, water, forest and wild life acts, issues involved in
enforcement of environmental legislation.

UNIT V
Social Aspects and the Environment: Water conservation, watershed management, and
environmental ethics. Climate change, global warming, acid, rain, ozone layer depletion.
Environmental protection act, population explosion.
Disaster management: Types of disasters, impact of disasters on environment, infrastructure,
and development. Basic principles of disaster mitigation, disaster management, and
methodology, disaster management cycle, and disaster management in India.


Suggested Reading
1. A. K. De, Environmental Chemistry, New Age Publications, 2002.
2. E.P. Odom, Fundamentals of Ecology, W.B. Sunders Co., USA.
3. GL. Karia and R.A. Christian, West Water Treatment, Concepts and Design Approach, Prentice Hall of India, 2005.
4. Benny Joseph, Environmental Studies, Tata McGrawHill, 2005
5. V.K. Sharma, Disaster Management, National Centre for Disaster Management, IIPE, Delhi, 1999.

Important questions and answers

Write about function of producers, consumers and decomposers in an ecosystem
The ecosystem can be divided, from the energetic view point into three types of organisms:
producers, consumers, and reducers. These can be explained as under:
(1) Producer
Photosynthetic algae, plants and bacteria are the producers of the ecosystem; all other
organisms depend upon them directly or indirectly for food.
(2) Consumers
Consumers are herbivorous, carnivorous, and omnivorous animals; they eat the organic
matter produced by other organisms.
(3) Decomposers
Decomposers are heterotrophic organisms like animals; they are fungi and bacterial that
decompose dead organic matter.

Describe the concept of an ecosystem
Every living organism has to depend and interact with different nonliving or abiotic and living or biotic components of the environment.
The abiotic environmental components include basic inorganic elements and compounds such as water and carbon dioxide, calcium and oxygen, carbonates and phosphates besides physical factors such as soil, rainfall, temperature, moisture, winds, currents and solar radiation.
The biotic environmental factors comprise plants, animals, and microbes.
The scientific study of the interactions of organisms with their physical environment and with each other, is called ecology.
The eco-system can be defined as any spatial or organizational unit including living organisms and non-living substances interacting to produce an exchange of materials between the living and non-living parts. The eco-system can be studied from either structural or functional aspects.
1. Structural Aspect
The structural aspects of ecosystem include a description of the arrangement, types and
numbers of species and their life histories, along with a description of the physical features
of the environment.
2. Functional
The functional aspects of the ecosystem include the flow of energy and the cycling of
nutrients.

Write brief notes about endangered and endemic species of India
Endangered species in comprise of a variety of rare species of wild animals, aquatic animals and insects. Some of the endangered species in India are Himalayan wolf, crocodile nico barica, red panda, etc. Endangered species are of four types:
Critically endangered (CR)
Endangered (EN)
Vulnerable (VU) and
Threatened
Endemic species are those species that are specific to a specific locality. It may also relate to a disease or pathogen that is confined to one particular area. One particular species endemic to India is the black buck.

Write briefly about conservation of biodiversity
Biodiversity is the degree of variation of life forms within a given species, ecosystem, etc. Biodiversity generally tends to cluster in hotspots. Biodiversity is commonly used to replace the more clearly defined and long established terms. Biologists define biodiversity as the totality of genes, species or ecosystem of a region.
Biodiversity is not evenly distributed. It varies greatly across the globe as well as within regions. Biodiversity is directly and indirectly related to human health as it provides support for drug discovery and is a valuable medicinal resource.
It plays a part in regulating the chemistry of our atmosphere and water supply. It is directly involved in water supply, recycling nutrients and providing fertile soil.
Habitat destruction in the form of deforestation of tropical forests has led to extinction of wildlife.
Biodiversity can be conserved by the following techniques:
In-situ conservation and
Ex-situ conservation

Write briefly about the biogeographical zones in India

There are 10 biogeographical zones in India. They are briefly described below:

1. Trans-Himmalayas: The Trans-Himmalayas is an extension of the Tibetean plateau.

2. Himalayas: The Himalayas form the northern boundary of India. The Himalayas comprises a diverse               range of biotic provinces and biomes.

3. Desert: Three kinds of deserts are found in India. They are, Desert of western Rajasthan, Desert of               Gujarat and the high altitude cold desert of Jammu & Kashmir and Himachal Pradesh

4. Semi-arid: This zone lies in between the desert and the Deccan plateau.

5. Western Ghats: This is a mountain range that runs along the western coast of India. This ghat section             covers a diverse range of biotic provinces and biomes.

6. Deccan Plateau: It is a large triangular plateau south of Narmada valley. The Satpura mountains cover           the north side, western ghats and eastern ghats cover the west and east sides respectively. The plateau           slopes towards east. The plateau is covered with deciduous vegetation.

7. Gangetic plain: The Gangetic plains cover from south of the Himalayas to north of tropic of cancer.               These plains were formed by the Ganges river system and are relatively homogenous. The famous                 'sunderban' forests are located in these plains.

8. North-east India: The plains and non-himalayan hill ranges of northeastern India fall in this zone. This             zone is filled with a wide variety of vegetation.

9. Islands: The Andaman and Nicobar islands in the bay-of-bengal is a group of 300 small and large                 islands. Mostly tribes live in Nicobar islands. These islands have a highly diverse set of biomes.

10. Coasts: The Indian subcontinent is blessed with a long coastline on the east and west with distinct                   differences between the two.

Write notes on threats to biodiversity

Biodiversity has evolved simultaneously with human culture. Man has met the changing needs and pressures of increasing population by applying knowledge and skills. People have hunted, fished and gathered species for food, fuel, fiber and shelter thereby eliminating competing or threatening species.

Activities mentioned above destroys and depletes the basis of an ecosystem (genes and species). As a result, mankind loses food, medicine and industrial products in the present and future.

According to the World Conservation Union's Red List, the threat to biodiversity is due to human activity particularly, habitat destruction.

Few of the Major biodiversity threats are listed below:

i. Habitat destruction

ii. Extension of agriculture

iii. Filling-up of wetlands

iv. Conversion of rich biodiversity site for human settlement and industrial development

v. Destruction of coastal areas

vi. Uncontrolled commercial exploitation

One of the primary causes of loss of biodiversity is habitat destruction. The main causes for the same are listed below:

i. Agricultural activities

ii. Extraction including mining, fishing, logging and harvesting

iii. Developmental activities including human settlement, industry and associated infrastructure

Millions of hectares of forest area is lost due to illegal encroachment of forest land. Forest land is also lost due to construction of river valley projects, introduction of transmission lines and roads, etc. Change in forest composition and quality can lead to decline in primary food species for wildlife.

Fragmentation is the process of division of a population into several small groups. Habitat loss and fragmentation leads to formation of isolated, small and scattered populations which are susceptible to inbreeding, depression, high infant mortality and eventually possible extinction.

Introduced species are responsible for many recorded species extinctions, especially on islands. In these isolated ecosystems, a new predator, competitor or pathogen can rapidly endanger species that did not evolve simultaneously with the newcomer.

Several forest, fisheries and wildlife resources have been over-exploited to the point of extinction. A few cases are mentioned below as a point in case. Poaching of wild animals (The Tiger, Elephant, Rhinoceros) has resulted in their extinction. Population pressures adversely affect the forest resources on which the local communities depend while having a negative impact on biodiversity.

Pollutants strain ecosystems. Contamination affects the food chain. A point in case is marine pollution from non-point sources that ruins estuaries and coastal seas throughout the world. Pesticides used to control agricultural pests have shown to negatively impact birds due to severe air pollution in Spain.

Write about energy flow in an ecosystem

Energy is an essential requirement for all living organisms. Solar energy is the only source of energy for the Earth. Solar energy is transformed to chemical energy by photosynthesis in plants (primary producers). Though lot of sunlight falls on plants, only 1% of this is utilized for photosynthesis.

Some amount of energy is used by the plant for growth and the remaining is transferred to consumers by the process of eating. Thus energy enters the ecosystem through photosynthesis and passes through different feeding levels (tropic levels)

The flow of energy through an ecosystem follows two laws of thermodynamics:

1. First law of thermodynamics states that “energy can neither be created nor destroyed, but can be converted from one form to another.” Ex: Energy for an ecosystem comes from the sun. It is absorbed by plants where it is converted and stored as chemical energy or solar energy is converted into chemical energy.

2. Second law of thermodynamics states that “whenever energy is transformed, there is a loss of energy through the release of heat.” Ex: Whenever energy is transferred between tropic levels, loss of energy takes place through respiration, running, hunting, etc.

Describe aquatic ecosystem

Aquatic ecosystem deals with water bodies. Types of organisms found in aquatic environment depend on salinity of water (salt content).

Types of aquatic life zones:

1. Fresh water life zones (Ponds, Streams, Rivers, Lakes)

2. Salt water life zones. (Oceans and Estuaries)

Pond ecosystems

i. Pond is temporary, only seasonal

ii. It is a stagnant freshwater body

iii. It is easily polluted due to limited amount of water.

Structure and function

Examples of abiotic components are temperature, light, water, organic and inorganic compounds.

Biotic components are comprised of 

i. Producers: These include green photosynthetic organisms. They are of two types:

a) Phytoplankton and

b) Microphytes

Phytoplankton are microscopic aquatic plants, which float freely on the surface of water. Examples of phytoplankton are Algae, Volvox, Pandorina, Anabena and Cosmarium.

Microphytes are large floating plants and submerged plants. Examples of microphytes are hydrilla, jussiaea, wolfia and demna.

 

ii. Consumers:

Primary consumers (Zooplanktons): These are microscopic animals that freely float on the surface of water. Zooplanktons are found along with phytoplanktons which they eat. Examples of zooplanktons are planktons, very small fish, ciliates, flagellates and protozoans.

Secondary consumers (Carnivores): They feed on zooplanktons. Examples of carnivores are insects like water beetles and small fish.

Tertiary consumers: They feed on smaller fish. Examples of tertiary consumers are large fish like game fish.

iii. Decomposers: They decompose dead plant and animal matter and their nutrients are released and reused by green plants. Examples of decomposers are fungi, bacteria and flagellates.

Lake ecosystems:

i. Lakes are natural shallow water bodies

ii. Lakes are supplied with water from rainfall, melting snow and streams.

iii. Lake is a permanent water body with large water resources.

iv. Lakes help in irrigation and supplying drinking water.

Structure and function of Lake Ecosystem: The abiotic components of lake ecosystems consist of temperature, light, proteins, lipids, turbidity, oxygen and carbon-dioxide.

The biotic components are classified into:

i. Producers: Green plants (Floating, Submerged and amphibious). Examples of producers are phytoplanktons, algae and flagellates.

ii. Consumers: Primary consumers are zooplanktons like ciliates, protozoans, etc that feed on phytoplanktons.

Secondary consumers  are carnivores like insects and smaller fishes that feed on zooplanktons

Tertiary consumers feed on smaller fish. Examples are large fish and game fish

iii.     Decomposers: Decomposers decompose dead plants and animals. Examples of decomposers are bacteria, fungi and actinomycetes.

River Ecosystem: 

i. It is fresh water and freely flowing water system

ii. Flowing water allows mixing of water resulting in higher dissolved oxygen

iii. River deposits large amount of nutrients.

Structure and function of River Ecosystem: The abiotic components of river ecosystems are temperature, light, pH, nutrients, organic and inorganic compounds.

Biotic components are classified into:

i. Producers: Phytoplankton, Algae, water grasses, aquatic grasses and other amphibious plants.

ii. Consumers: Primary consumers feed on phytoplanktons. Examples are water insects, snails and fishes.

Secondary consumers are feed on primary consumers.

iii.     Decomposers: Decomposers decompose dead plants and animals. Examples of decomposers are bacteria, fungi and actinomycetes.

 

Ocean ecosystems:

i. Oceans occupy a large surface area and made up of saline water.

ii. Commercial activities are carried out in oceans.

iii. Oceans are rich in biodiversity

iv. Oceans moderate the temperature of the earth.

Structure and function of Ocean Ecosystems:

The abiotic components of ocean ecosystems are temperature, light, NaCl, K, Calcium and Magnesium salts and alkalinity.

The biotic components comprise of 

i. Producers: Phytoplanktons (diatoms, unicellular algae, etc) and marine plants (sea weeds, chlorophyceal, phaeophyceae)

ii. Consumers: They are heterotrophic macroconsumers which depend upon producers for their nutrition.

a. Primary consumers or herbivores feed on producers (Ex: Crustaceans, Mollusks, Fish

b. Secondary consumers or carnivores feed on herbivores (Ex: Herring, Mackerel, etc)

c. Tertiary consumers are the top consumers and feed on small fishes. (Ex: Cod, Haddock, etc)

iii. Decomposers decompose dead organic matter. (Ex: Bacteria and fungi)

Estuarine ecosystem:

i. Estuaries are transition zones that are strongly affected by tides of the sea.

ii. Water in estuaries change periodically

iii. The organisms in estuaries have a wide tolerance

iv. Salinity remains highest in summer and lowest in winter.

Structure and function of Estuarine Ecosystems:

Abiotic components of estuarine ecosystems are temperature, pH, sodium and potassium salts and nutrients.

Biotic components consist of

i. Producers: Examples are marsh grasses, seaweeds, seagrasses and phytoplankton.

ii. Consumers: Examples are Oysters, Crabs, Seabirds, and small fishes

iii. Decomposers: Examples are Bacteria, fungi and actinomycetes.

Write in detail about structure and function of an ecosystem.

Ecology is the study of ecosystems and ecosystem is the basic functional unit of ecology. A group of organisms interacting amongst themselves and with the environment is called ecosystem. An ecosystem is a community of different species interacting with each other and their non-living environment thereby exchanging energy and matter.

Structure of an ecosystem shows the relationship between abiotic and biotic components. 

All the living members of an ecosystem form the biotic community. Ex: Plants (producers), animals (consumers) and microorganisms (decomposers).

The non-living components (physical and chemical) of an ecosystem collectively form the abiotic community. Ex: Climate, Soil, Energy, Nutrients, Water and Air.

Physical components are necessary for the growth and maintenance of living components of the ecosystem.

Chemical components are the source for essential nutrients. They consist of organic substances (protein, lipids, carbohydrate) and inorganic substances (Al, Co, Zn, Cu-micro elements C, H, O, P, N, P, K-macro elements)

Function of an ecosystem is of three types:

Primary function: The primary function of all ecosystems is to manufacture starch (photosynthesis)

Secondary function: The secondary function of all ecosystems is to distribute energy to all the           consumers in the form of food.

Tertiary function: All living organisms die and these dead systems are decomposed to initiate the third system of ecosystems called “cycling”.

Define and differentiate between food chain and food web with a diagram

A food chain is a model that shows the flow of energy from autotrophs to a series of organisms in an environment. The energy that flows can be different for each food chain. The food chain describes the flow of food from one organism to the next thereby giving energy to the organism digesting the food. The number of steps involved in a food chain is restricted to four or five. The energy available decreases with each step. The energy loss takes place in the form of heat. The three types of food chains are: 

Grazing food chain,

Detritus food chain and 

Parasitic food chain. 

All food chains start with the sun.

The interlocking pattern of various food chains in an ecosystem is known as food web. In a food web many food chains are interconnected. In a food web different types of organisms are connected at different tropic levels resulting in several opportunities of eating and being eaten at each tropic level.

An important difference between food chain and food web is that food chain is linear and this implies that if one species becomes extinct, the species in the subsequent tropic levels are also affected. However, in a food web, if one species is affected, there is no serious effect on other tropic levels as there are several options available at each tropic level.

Enumerate the value of biodiversity

The value of biodiversity is classified into:

Direct values and

Indirect Values

Direct value of biodiversity: Biodiversity has direct value in the form of consumption in agriculture, medicine and industry. Among all plant species identified as fit for human consumption, only 150 have been cultivated on a large scale. Two types of direct values are:

  Consumptive use value and 

Productive use value

Consumptive use value is the value placed on nature's products that are consumed directly without passing through a market. Consumptive use value is not included in national income accounts. Consumptive use value benefits the communities closest to the resource if harvested sustainably with proper management. Product examples of consumptive use value are firewood, food and game meat.

Productive use value refers to products that are commercially harvested and sold in a market. Its value is estimated at production end after addition of cost and value. The productive use value has a major impact on national economy. Product examples of productive use value are timber, fish, honey, mushrooms, game meat sold in markets and medicinal plants.

Biodiversity has indirect value since it provides economic benefits without being harvested. Direct value of biodiversity is derived from its indirect value. Indirect value of biodiversity is listed below:

Non consumptive use value

Optional value

Existence value and

Information value

Non consumptive use value refers to nature's functions and services. Examples of this are photosynthesis by plants that provides support system for other species, maintenance of water cycle, regulating climate, production and protection of soil, absorption and breakdown of pollutants, recreational, aesthetic, socio-cultural, scientific, educational, spiritual and historic values of natural environments.

Option value refers to the indirect value of a species potential to produce economic benefits to the society in the future.

Existence value is the value gained from continuous knowledge of existence. An example in this context is the expense incurred by the administration of various countries to develop techniques in order to prevent a species from becoming extinct (Giant Panda, Blue whale, White tiger, etc).

Information value refers to the educational, scientific, aesthetic and tourism values of biodiversity in an ecosystem.

What are the types of  biodiversity conservation

With the rapid increase of human population and resulting expansion of man's needs coupled with scientific knowledge led to over-exploitation of natural resources. Eventually, conservation of biological diversity became a global concern. This involves influencing behaviour of people at local level through education, at the national level through policy work and awareness programs. International corporations should ensure that their business do not contribute to further loss of biodiversity.

The two main types of biodiversity conservation are:

In-situ conservation and

Ex-situ conservation

In-situ conservation is defined as the conservation of genetic resources through their maintenance within natural or man-made ecosystems in which they occur.

In-situ conservation effort is setting-up of protection areas. This technique is the best conservation strategy. However, its implementation is sometimes unfeasible. National Parks, Sanctuaries and Biosphere reserves are some types of in-situ conservation.

Ex-situ conservation is defined as conservation made outside the habitat of an ecosystem. In case the habitat of rare or endangered species is destroyed, ex-situ conservation is the only means of conserving  a species. It also provides a back-up solution to in-situ conservation projects. A few examples of ex-situ conservation are seed banks, botanical gardens, pollen storage, tissue culture and genetic engineering

Biogeochemical cycles: Phosphorus cycle

Form taken up by plant:                                    H2PO4-, HPO4=
Mobility in soil:                                            None; roots must come in direct contact with                                                                                                orthophosphate P
Mobility in plant:                                    Yes
Deficiency symptoms:                                    Lower leaves with purple leaf margins
Deficiency pH range:                                           <5.5 and >7.0
Toxicity symptoms:                                      None
Toxicity pH range:                                   Non toxic (optimum availability pH 6.0-6.5)
Role in plant growth:                                   Important component of phospholipids and nucleic acids                                                                               (DNA and RNA)
Role in microbial growth:                                     Accumulation and release of energy during cellular                                                                                       metabolism
Concentration in plants:                                   1,000 – 5,000 ppm (0.1 –0.5%)
Effect of pH on availability:                           H2PO4- at pH < 7.2
                                          HPO4= at pH > 7.2
P fertilizer sources:                                           Rock phosphate, phosphoric acid, Ca orthophosphates,                                                                               ammoniumphosphates, ammonium poly-phosphates, nitric                                                                             phosphates, K phosphates, microbial fertilizers                                                                                            (phosphobacterins) increase P uptake

The Water Cycle

The Water Cycle

Water is constantly being cycled through the atmosphere, ocean, and land. This process, known as the water cycle, is driven by energy from the sun. The water cycle is crucial to the existence of life on our planet. 

• During part of the water cycle, the sun heats up liquid water and changes it to a gas by the process of evaporation.   Water that  evaporates from Earth’s oceans, lakes, rivers, and moist soil rises up into the atmosphere.
• The process of evaporation from plants is called transpiration. 
• As water (in the form of gas) rises higher in the atmosphere, it starts to cool and become a liquid again.  This process is called condensation.   When a large amount of water vapor condenses, it results in the formation of clouds.
• When the water in the clouds gets too heavy, the water falls back to the earth.  This is called precipitation.
• When rain falls on the land, some of the water is absorbed into the ground forming pockets of water called groundwater.  Most groundwater eventually returns to the ocean.  Other precipitation runs directly into streams or rivers.  Water that collects in rivers, streams, and oceans is called runoff.

Biogeochemical cycles: Sulphur cycle

Biogeochemical cycles: Sulphur cycle

• Sulfur- S, it is an element
• Naturally found in earth
• At room temperature it is a solid
• Present in proteins, amino acids, vitamins, and enzymes, necessary for plants and animals
• Often reacts with hydrogen creating hydrogen sulfide (H2S)
• Can dissolve in water
• With metals in water, forms metal sulfides and sulfates in air

Presence:

• In ground: most found in rocks, or salt in earth, or as sediment at bottom of ocean
• Found as S, H2S, SO4-2, (NH4)2SO4
• Underground: Plants absorb, or left by acid deposition (fog or precipitation)
• Found as SO4-2, (NH4)2SO4, converted to H2S by bacteria, decay, and plant use
• Stored: Ground, rock, ocean, some quantities in air

Cycle:

• Sulfur is transferred into biosphere then back into ground, or from ground to atmosphere
• Microorganisms turn it into H2S (gas) 
• Oxidized in atmosphere to SO2, and then to H2SO4 (an acid) with water contact
• Mined ores released to atmosphere in factories as H2S and SO2
• Volcanoes and hot springs
• Deposited next in water
• Through precipitation, dry deposition, leaching
• SO4-2 leaches from soil into ocean as sediment
• H2SO4 falls into ocean
• Dimethyl Sulfide, carbonyl sulfide (biogenic gases), released by plankton returns back into atmosphere (turns into SO2)
• Either re-evaporated, left as sediment for long time, or deposited on land 
• When back on land, cycle repeats

Sulphur cycle driven by:

• constant addition of sulfur to environment by earths interior (Geosphere)
• Human disturbance, addition of sulfur to atmosphere, (also dug up from environment)
• Natural processes (Biological, Hydrological and due to Sun’s energy)
• Plant uptake, microbes (Desulfovibrio sp. or Desulfotomaculum sp.)

Presence:

• Most sulfur in particulate form
• Therefore it is a sedimentary cycle
• Very short residence time in atmosphere (1-2 days)
• Even in atmosphere, found as aerosols (<1 micrometer), not gas usually
• In atmosphere, very much less than 1%
• 90-95% SO2 from power plants and factories

Sources:

• In the process of mining ores, sulfur/sulfides released into soil
• Combustion of fossil fuels
• Release of SO2, causes acid rain, increases amount already present
• Almost 30% of sulfur in rivers from pollution, mining, erosion, etc.
• Sulfur cycle but also upset balance- too much Sulfur induces acid rain
• Hydrodesulphurization (refining hydrocarbons)

Sulfur Cycle is important to biological and natural processes although human’s role impacts nature in a negative way
Driving force for life

Biogeochemical cycles - Oxygen cycle

THE OXYGEN CYCLE

• Oxygen, one of the main components of the Earth’s atmosphere
• Two oxygen atoms make up one oxygen molecule, and three oxygen atoms together make up the molecule called ozone.
• As a gas, oxygen is odorless, colorless, and highly reactive. 
• Oxygen is essential for the survival of many organisms, and, in the ozone, provides protection to life by filtering out the sun’s ultraviolet rays.
• In the oxygen cycle, oxygen atoms present in the earth circulate through a series of processes.  
• Like the nitrogen, carbon, and water cycles, the oxygen cycle is a biogeochemical cycle.
• A biogeochemical cycle is the movement of matter through the biotic and the abiotic spheres of the ecosystem.

The oxygen cycle begins with plants and photosynthesis.

• Through photosynthesis, plants convert the energy from the sun and water into carbohydrates and oxygen. 
• During the day: plants convert carbon dioxide into oxygen.
• During the night: plants convert oxygen into carbon dioxide to maintain their metabolism.

Oxygen in water

Oxygen in water is known as dissolved oxygen. When water runs over rocks, oxygen enters and creates a lot of high surface area which allows oxygen to transfer from the air into the water very quickly. 

Animals contribution to the oxygen cycle

Animals breathe in oxygen and breathe out carbon dioxide through their processes of metabolism, sparking the process of photosynthesis, once again linking back to the plants’ contribution to the oxygen cycle. 

The Three Main Reservoirs of Oxygen

• Biosphere (living things)
• Lithosphere (Earth’s crust)
• Atmosphere (air)

Within the biosphere and atmosphere, plants begin the oxygen cycle and animals continue it.

Photolysis also donates to a large portion of the oxygen in the atmosphere, where high energy ultraviolet radiation breaks down the atmospheric water and nitrate. 

Figure depicting the interrelationship of Atmosphere, Hydrosphere, Biosphere, Ecosphere and Oxygen

Much of the oxygen present in the atmosphere is used during respiration and decay mechanisms, where animal life and bacteria consume oxygen and release carbon dioxide.

Oxygen is also cycled between the biosphere and lithosphere.

Ecologists fear that there may come a time when the amount of carbon dioxide is very large and there are too few plants to covert it into Oxygen. 

Hence, it is essential that we reduce pollution and protect our environment in order to maintain a well functioning oxygen cycle.

Biogeochemical cycles - Nitrogen cycle

Nitrogen Cycle

Sources of Nitrogen

• Lightning
• Inorganic fertilizers
• Nitrogen Fixation
• Animal Residues
• Crop residues
• Organic fertilizers

Forms of Nitrogen

Urea = CO(NH2)2

Ammonia = NH3 (gaseous)

Ammonium = NH4

Nitrate = NO3

Nitrite = NO2

Atmospheric Dinitrogen = N2

Organic Nitrogen

Role/Importance of Nitrogen

• Plants and bacteria use nitrogen in the form of NH4+ or NO3-
• It serves as an electron acceptor in anaerobic environment
• Nitrogen is often the most limiting nutrient in soil and water.
• Nitrogen is a key element for:
• amino acids
•  nucleic acids (purine, pyrimidine) 
• cell wall components of bacteria

Nitrogen Cycles

• Ammonification/mineralization
• Immobilization
• Nitrogen Fixation 
• Nitrification
• Denitrification

Ammonification or Mineralization or Nitrogen fixation

• Decomposers: earthworms, termites, slugs, snails, bacteria, and fungi
• Uses extracellular enzymes  initiate degradation of plant polymers
• Microorganisms uses:
• Proteases, lysozymes, nucleases to degrade nitrogen containing molecules

When plants or bacterial cells die, they release of organic nitrogen 

Organic nitrogen is converted to inorganic nitrogen (NH3)

When pH is less than 7.5, NH3 is converted rapidly to NH4

Immobilization

• It is the opposite of mineralization
• Takes place when nitrogen is limiting in the environment
• Nitrogen limitation is governed by C/N ratio
• C/N typical for soil microbial biomass is 20
• C/N < 20 Mineralization takes place
• C/N > 20 Immobilization takes place

Nitrogen Fixation is

• Energy intensive process
• Performed only by selected bacteria and actinomycetes
• Performed in nitrogen fixing crops (ex: soybeans)

Microorganisms responsible for fixing nitrogen are:

• Azobacter
• Azospirillum
• Clostridium
• Cyanobacteria

They

• Require the enzyme nitrogenase
• Inhibited by oxygen and ammonia (end product)

Nitrification

Two step reactions that occur together :

First step catalyzed by Nitrosomonas

Second step catalyzed by Nitrobacter

Optimal pH is between 6.6-8.0

Denitrification

Removes a limiting nutrient from the environment

Inhibited by O2

Not inhibited by ammonia

Microbial reaction

Nitrate is the terminal electron acceptor

Multidisciplinary nature of environmental science

Multidisciplinary nature of environmental science

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

There are three reasons for studying the state of the environment.

1. Need for information that clarifies modern environmental concepts like equitable use of natural resources, more sustainable life styles etc. 
2. Need to change the way in which we view our own environment, using practical approach based on observation and self learning. 
3. Need to create a concern for our environment that will trigger pro-environmental action, including simple activities we can do in our daily life to protect it.

Environmental science is essentially the application of scientific methods and principles to the study of environmental issues.

Scope of environmental studies
Since the environment is complex and actually made up of many different environments, including natural, constructed and cultural environments, environmental studies is the inter disciplinary examination of how biology, geology, politics policy studies, law, geology, religion engineering, chemistry and economics combine to inform the consideration of humanity’s effects on the natural world. This subject educates the
students to appreciate the complexity of environmental issues and citizens and experts in many fields. By studying environmental science, students may develop a breadth of the interdisciplinary and methodological knowledge in the environmental fields that enables them to facilitate the definition and solution of environmental problems.

The scope of environmental studies is that, the current trend of environmental degradation can be reversed if people of educated communities are organized and empowered; experts are involved in sustainable development.

Environmental factors greatly influence every organism and their activities. The major areas in which the role of environmental scientists are of vital importance are natural resources, ecosystems, biodiversity and its conservation, environmental pollution, social issues and environment human population and environment.
It is essentially a multidisciplinary approach and its components include Biology, Geology, Chemistry, Physics, Engineering, Sociology, Health Sciences, Anthropology, Economics, Statistics and Philosophy It is essentially a multidisciplinary approach. An Understanding of the working of the environment requires the knowledge from wide ranging fields.

Biogeochemical cycles - Carbon cycle in brief

Carbon exists in the nonliving environment as:
• Carbon dioxide (CO2)
• Carbonic acid ( HCO3−)
• Carbonate rocks (limestone and coral = CaCO3)
• Deposits of Fossil fuels
• Dead organic matter

Organic Carbon

• Hydrocarbons:  CH4

• Carbohydrate: CH2O

Inorganic carbon

• Carbon Dioxide: CO2

• Calcium Carbonate: CaCO3 

Carbon is released into the atmosphere in several ways

• Respiration by plants and animals. 

• Decay of animal and plant matter. 

• Combustion of organic material

• Production of cement. 

• The ocean releases CO2 into the atmosphere.

• Volcanic eruptions and metamorphism

Carbon is taken from the atmosphere in several ways

• Photosynthesis. 

• The oceans when the  seawater becomes cooler, more CO2  dissolve and become carbonic acid.

• In the upper ocean areas organisms convert reduced carbon to tissues, or carbonates.

Photosynthesis

• CO2   + H2O  + sunlight   =>  CH2O  + O2

Respiration 

• CH2O  + O2   =>  CO2   + H2O  + energy

Human Impacts on the Carbon Cycle => Combustion or Oxidization of hydrocarbon

86% of global primary energy consumption is fossil fuels.

Fossil Fuels

• Petroleum

• Natural Gas

• Coal

CO2 Concentration

Pre-Industrial value => 280 ppm  (600 billion tons)

Current value => 380 ppm (800 billion tons)

Critical value => 560 ppm (1200 billion tons)

Question Bank

Define Environment and Ecology
Discuss the multidisciplinary nature of Environmental Studies
Discuss the role played an individual in protecting the environment
Write short notes on the atmosphere, hydrosphere, lithosphere and biosphere.
What is the importance of Environmental studies
Briefly discuss the various natural resources available to man and their significance
Explain "conflicts over water"
List the effects of floods and droughts
What is a "dam" ? List its advantages and disadvantages
Classify energy resources with examples and give reasons for the ever increasing need for energy
Describe land as a "resource". Explain in detail with examples/case studies about different forms of land degradation
Describe in detail about the disadvantages of modern agriculture

Define an ecosystem. Explain the structure of an ecosystem and list its functions in detail
Explain the "energy flow in an ecosystem" with the help of a diagram
List the functions of producers, consumers and decomposers in an ecosystem with examples
List the various types of aquatic ecosystems with examples and sketches wherever necessary
Describe food chain, food web and ecological pyramid with examples and a sketch wherever necessary
Draw the different types of ecological pyramids with a brief description

Explain biodiversity with reference to genetic, species and ecosystem biodiversity
Describe  bio-geographical classification of India
Describe briefly the value of biodiversity
Describe the  threats to biodiversity and the various methods used in the conservation of bidiversity
Define endangered and endemic species and list the endangered and endemic species of India

List the causes, effects and control measures for:
Air pollution
Water pollution
Soil Pollution
Noise pollution
Thermal pollution
Explain about solid waste management
Explain briefly Air act, Water act, forest act and wildlife acts.
Describe briefly the issues involved in enforcement of environmental legislation

List the techniques of water conservation
Explain Watershed management
Describe environmental ethics
Describe climate change, Global warming, acid rain and ozone layer depletion
Discuss environment protection act
Explain Population explosion
Classify disasters  and list their impacts on environment, infrastructure and development.
Describe the basic principles of disaster mitigation, disaster management and methodology.
Draw and explain the disaster management cycle
Explain disaster management in India

QUESTIONS THAT ACTUALLY APPEARED IN UNIVERSITY EXAMINATIONS
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Explain the need for public awareness regarding environment
Write a note on non-renewable energy sources
Explain food chain and food web
Write briefly about estuarine ecosystem
What are the causes and ill-effects of acid rain
Write about the significance of environmental ethics for sustainable environmental quality
Classify solid waste based on disposal mechanism
Write a short note on energy resources in India
Define ecological pyramid
State the types of disaster and their ill-effects on environmental quality
Critically comment on the conflicts of interstate sharing of water resources
Write the remedial measures to be taken for overcoming the problems due to over-utilization of fertilizers and pesticides
Discuss in detail the importance of small and medium earth-fill dams
Explain the possible environmental impacts of major dams
Mention the causes and effects of Salinity of soil and deforestation
Discuss the type, characteristic features, structure and function of pond ecosystem
Illustrate with a neat sketch, the methods of recharging ground water resources
Write about the causes, effects and control measures of thermal pollution
Describe the methods to control noise pollution due to traffic and industries
Describe briefly global warming and ozone layer depletion
Discuss contribution of automobiles to air pollution and list the control measures that can be adopted
Explain the powers and functions of central pollution control board under water act
Write a short note about environmental enforcement and regulations
Write about wildlife protection act its salient features and limitations
Briefly describe the different methods of water conservation and watershed management.
Define ecosystem and environment
What is bio-magnification
Distinguish between lentic and lotic ecosystems
Briefly describe the values of biodiversity with necessary examples
Explain the different types of ecological pyramids
What is noise pollution
What are green-house gases
List the various natural disasters
What are acid rains
List the various flood control measures
Discuss the advantages and disadvantages of dams
Define soil erosion and list the causes
Differentiate between food webs and food chains with examples
Define producers, consumer, decomposers and detrivores with examples
List the threats to bio-diversity
Explain genetic, species and ecosystem diversity with examples
List the salient features the water act, 1974
List the effects of air pollution on man, materials, plants and animals
"Only if we take care of nature, nature will take care of us" - Explain
Write short notes on "disaster management"
Write about "man's impact on the environment"
Explain endangered and endemic species
Explain briefly about:
Decomposers
Deforestation
Nuclear hazards
Property rights
Agro-forestry
Nuclear energy
Value education
Soil Erosion
Solid waste
Define ecosystem and discuss the structural aspects of ecosystem
What is biodiversity and describe the different methods of its conservation
Explain the importance of natural resources
Discuss the management of natural resources
What are the causes and effects of air pollution
Discuss the various environmental problems in India
Explain the role of individuals in the prevention of pollution
Briefly explain water harvesting and watershed management
Explain briefly about:
Environment
Food Chain
Atmosphere
Estuary
Green house effect
Noise pollution
Population growth
Ozone layer depletion
Acid rain
Wildlife protection act
Describe energy flow in an ecosystem
Describe the forest ecosystem
Write briefly about solar energy
Describe the various water resources
Briefly describe environmental disasters and the bhopal gas tragedy
Discuss the causes, effects and control measures of solid waste
List the various causes and effects of water pollution
Describe briefly:
Biosphere
Watershed management
Thermal pollution
Genetic diversity
Sulphur cycle
Cyclones
Forest conservation act
Industrial wastes
What is an ecological pyramid and describe the various types of ecological pyramids
List the different types of ecosystems and describe their characteristics briefly
Explain the concept of biodiversity
What is nuclear pollution and describe its control measues in brief
Disuss soil pollution in brief
Describe the desert ecosystem
Discuss the effect of the environment on human health
Discuss environmental ethics and resource use
Describe briefly:
Biomass energy
Detritus food chain
Forest resources
Mitigation of pollution due to mining
Wastewater pollution
Photochemical smog
Air pollution act
Waste land reclamation
Describe the structure of pond ecosystem
What is meant by ecological succession
Draw the biogeochemical cycles
Describe land resources
Discuss the causes, effects and prevention of water pollution
Discuss rehabilitation and resettlement
Describe biodivesity
Elaborate on the biogeographic regions in India
Write short notes on:
Nitrogen cycle
Wind energy
Dams
Ex-situ conservation
Conflicts over water
Population pressure
Environment protection act
Earthquakes
Discuss in detail the forest ecosystem
Explain loss of biodiversity
Explain the management of land resources
Describe noise pollution and measures to reduce it
Explain global warming
Describe urbanization
Discuss in brief:
Food web
Deforestation
Nitrogen cycle
Mineral resources
Particulate matter as pollutants
Tidal energy
Relegan siddhi movement
Chipko movement
Wastewater pollution
Explain the interdisciplinary nature of science with the environment
Explain food resources
Write short notes on solar energy
Discuss marine pollution
Discuss ozone layer depletion
What is eutrophication
Describe briefly the principal pollutants that contaminate our air, water and land
Desine Environment
What are the components of the environment
Define deforestation and list tha causes of deforestation
What is groundwater
Classify mineral resources
Classify food production
Classify energy resources
List the various renewable energy sources
ist various methods to protect soil
Define ecosystem
List the characteristics of ecosystem
List the different types of ecosystems
List the biotic components of an ecosystem
List the abiotic components of an ecosystem
Define:
Autotrophs
Heterotrophs
Genetic diversity
Species diversity
Ecosystem diversity
Biogeography
Biodiversity hotspot
List the threats to biodiversity
List the reasons for habitat loss
Discuss the various methods for the conservation of biodiversity
Define air pollution
What are the sources of air pollution
Define particulate matter
Define SPM
Differentiate between mist amd fog
What are the various gaseous pollutants
What are the effects of air pollution on animals
List the effects of air pollution on physical properties of atmosphere
What are the effects of carbon monoxide on human health
How can air pollution be controlled at source
What equipment is used to control gaseous pollutants
What equipment can be used to control particulates
What is a bag filter
Describe briefly wet scrubbers.
Differentiate between point and non point source pollutants with examples
How do nutrients from agricultural fields affect watershed
Define:
Soil pollution
Marine pollution
What are the causes of marine pollution
What is the main purpose of processing in solid waste management
List the techniques of processing solid wastes
Define hazardous wastes
Define:
Biomedical wastes
List the benefits of pollution prevention