natural resources & its conservation

Environmental Studies

NATURAL RESOURCES

Introduction: Life on this earth depends upon a variety of goods and services provided by the nature which are known as ‘Natural Resources’. Thus water, air, soil, minerals, coal, forests, crops and wildlife are all examples of natural resources. Natural resources are the components of the atmosphere, hydrosphere and lithosphere and are useful and essential for life. They include air, water, plants, animals, soil, minerals and fossil fuels.

Def of Resource: Resources are defined as those materials which are required for the survival, comfort and prosperity of human beings on the earth.

Ecological Variables:The five basic ecological variables are Energy, Matter, Space, Time and Diversity are sometimes combined called as ‘Natural Resources’ as such laws which govern changes in these quantities, have great applicability in the resource use.

Classification of Resources: Nature has gives us abundant resources in the form of water, air, plants, land, animals, minerals, fossil fuels etc. The most popular concept of natural resource classification is Renewable & Non – Renewable.Natural resources are of two types

1. Renewable Resources2. Non – Renewable Resources1. Renewable Resources: which are in exhaustive and can be regenerated within a

given span of time.Ex: Forests, Wildlife, Wind energy etc

2. Non – Renewable Resources: which cannot be regenerated Ex: Fossil Fuels like coal, petroleum, minerals etc. Once we exhaust these resources, the same cannot be replenished even our renewable resources can become non – renewable if we exploit them to such extent their rate of consumption exceeds their rate of regeneration. It is very important to protect and conserve our natural resources and use them in a judicious manner so that we do not exhaust them.Non – renewable resources can be further divided into two categoriesa) Recyclable b) Non – Recyclablea) Recyclable: These are non – renewable resources which can br collected after they are used and can be recycled. There are mainly the non – energy mineral resources which occur in the earth’s crust. (Ex: Ores of Al, Cu, Hg etc) and deposits of fertilizer nutrients (Ex: Phosphate rock and Potassium and minerals used in their natural state).b) Non – Recyclable: There are non – renewable resources which cannot be recycled in any way

K, Syamala Devi, Asst. Prof, GNITS

1



2


MINERAL RESOURCESIntroduction: A mineral is a naturally – occurring substance of definite chemical composition and identifiable physical properties. An ore is a mineral or combination of minerals from which a useful substance, such as a metal, can be extracted and used to manufacture useful products. Minerals are formed over a period of millions of years in the earth’s crust. Iron, Zn, Al, Mn & Cu are important raw materials for industrial use. Important non – metallic resources include Coal, Salt, Clay, Cement & Silica. Stones used for building materials such as granite, marble, lime stone, constitute another category of minerals.

Some mineral elements are essential for the formation & functioning of the body in all living organisms like human beings, plants & animals etc. Mineral resources are present in the form of elements, chemical compounds. Minerals (or) rock concentrated in that form that can be extracted to obtain a sustainable commodity.

Definition: A mineral may be a chemical element (or) an inorganic compound (Ex: Iron Ore) existing naturally below the earth. The elements like Oxygen, Silicon, Iron, Manganese, Magnesium, Aluminium, Calcium and other combine in definite composition to form quartz, Felspar, Calcite, Bauxite etc.

Bauxite – Al2O3. 2H2OFelspar – K2O Al2O3. 6 SiO2

Corundum – Al2O3.

The Most Popular Mineral Elements in the Globe are:Iron, Silicon, Coal, Magnesium, Nickel, Calcium, Aluminium, Sodium, and Gold..

A mineral may be inorganic (or) organic, metal (or) non – metal, precious (or) non – precious minerals are available in small quantity (or) large in quantities.

Years to Depletion of Ore Deposition:S.NO RESOURCE YEARS TO

DEPLETION

1 Aluminium 31 Years2 Silver 133 Stanum 154 Zinc 185 Lead 216 Copper 217 Chromium 958 Iron 939 Mercury 1310 Manganese 46

Distribution of Mineral Resources:Mineral resources are non – renewable resources. The geographical Distribution of

mineral resources are very uneven in India.


3


According to Geological Information Systems (GIS) report, there are 50 mineral occurrences and more than 400 major mineral sites are available.

Indian Scenario: India is the producer of 84 minerals the annual value of which is about Rs 50,000 Crore. At least 6 major mines need a mention here which is known for causing severe problems.

a) Jadnguda Uranium Mine, Jharkhand – exploring to radio – active hazard.b) Jharia Coal Mines, Jharkhand – underground fire leading to land

subsidence and forces displacement of people.c) Sukinda Chromite Mines, Orissa – seeking of hexavalent Chromium into

river posing serious health hazard, Cr (VI) being highly toxic and carcinogenic.

d) Kudremukh Iron Ore Mine, Karnataka – causing river pollution & threat to bio – diversity.

e) East Coast Bauxite Mine, Orissa – Land encroachment & issue of rehabilitation unsettled.

Uses and Exploitation of Minerals:Mineral resources can be divided into several broad categories depending on their use,

such as elements for metal production and technology, building materials, chemical industry and for agricultural purposes.

Classification of Mineral Resources:From Utilization point of view, minerals are placed under two classes.

a) Expandable Mineralsb) Non – Expandable Minerals

Expandable Minerals: Expandable Minerals have practically no salvage value and once consumed (or) used we can’t recover again.Ex: Coal, Petroleum gas and most of the non – metallic minerals.

Non – Expandable Minerals: Non – Expandable Minerals are those which have good salvage value and can be again and again consumed through recycling, except those quantities that are lost due to corrosion and abrasion.Ex: Metallic Minerals

Important Minerals and their Uses:From origin point of view minerals are classified into two types.

a) Metallic Mineralsb) Non – Metallic Minerals


4


S.no Metallic Mineral Uses1 Aluminium Building Material, Electrical Wiring, Air Craft, Rockets etc2 Beryllium Refractories, Copper Alloys3 Chromium Refractory, Metallurgy, and Chemicals4 Cobalt Alloys, Radiography, Catalyst5 Copper Alloys, Electrical Products6 Gold Jewellery7 Iron Steel, Building Material8 Lead Batteries, Paints, Alloys9 Tin Tin Plates10 Uranium Nuclear Bombs, Electricity Generation11 Vanadium Alloys12 Manganese Alloy Steels13 Magnesium Structural Refractories14 Titanium Alloys, Pigment, Air Crafts15 Zinc Chemicals, Soldering, Dye Casting

Non – Metallic Minerals:

S.no Non Metallic Mineral

Uses

1 Asbestos Roofing, Insulation, Ceramics, Textile and Gasoline2 Corundum Abrasive3 Felspar Artificial Teeth4 Nitrates Fertilizers, Chemicals5 Phosphates Fertilizers, Chemicals6 Potassium Fertilizers, Chemicals7 Salt Chemicals, Glass, Metallurgy8 Sulphur Fertilizers, Acids, Iron & Steel Industry

Minerals are sometimes classified as Critical & Strategic.Critical Minerals: these are essential for the economy of a nation.Ex: Fe, Al, Cu, Au etc.Strategic Minerals: these are those required for the defense of a country.Ex: Mn, Co, Pt, Cr etc.Indian Mineral Resources:

India produces 64 mineral resources which includes 4 – Fuel Minerals11 – Metallic Minerals49 – Non – Metallic MineralsMajor Minerals of India: a) Energy Generating Minerals b) Other Commercially Used Minerals


5


a) Energy Generating Minerals: i) Coal & Lignite: West Bengal, Jharkhand, Orissa, Madhya Pradesh & Andhra Pradeshii) Uranium: Jharkhand, Andhra Pradesh, Meghalaya, Rajasthanb) Other Commercially Minerals: i) Aluminium: Jharkhand, Maharastra, West /Bengal, Madhya Pradesh, TamilNaduii) Iron(Hematite & MAgnetite): Jharkhand, Orissa, Madhya Pradesh, Andhra Pradesh, Tamilnadu, Karnataka, Maharastra & Goaiii) Copper(Copper Pyrites): Rajasthan, Bihar, Jharkhand, Karnataka, Madhya Pradesh, WestBengal, Andhra Pradesh & Uttarakahand.

Main Uses of Minerals:c) Development of industrial plants & machineryd) Generation of energy Ex: Coal, Lignite , Uranium etce) Construction , housing, settlementsf) Defense equipments – weapons, ornamentsg) Transportation meansh) Communication – telephone wires, cables, electronic devices etci) Formation of alloys for various purposes. Ex: Steel alloysj) Jewellery – Ex: Au, Ag, pt, Diamond etc

Ferro – Manganese Nodules:The Ferro – Manganese Nodules are commonly known as ‘Manganese Nodules ’

(or) ‘FM -Nodules’. FM – Nodules are generally found over the oceanic floors, generally below 4,000 m depth, re perhaps the most specular discovery in this field. It is estimated that 1 million ton of Ferro – Manganese Nodules from sea – bed provide about 2,75,000 tons of Manganese, 13,000 tons of Nickel, 2,500 tons of Cobalt and 1,000 tons of Copper besides other metals like Iron, Vanadium, Molybdenum, Silver and Lead.

India’s Principle Minerals:Coal: India is the fifth largest world produces of Coal, Bauxite, Copper, Gold, Iron ore, Diamond, Lead and Zinc are Principle minerals.NALCO: National Aluminum Company Limited (NALCO) is the largest Aluminum Company in India.

Mining Operations: Mining operations generally progress through four stagesa) Prospectingb) Explorationc) Developmentd) Exploitation

a) Prospecting: Searching for Mineralsb) Exploration: Assessing the size, shape, location and economic value of the

deposit.c) Development: The work of preparing access to be deposit so that the minerals

can be extracted from it.d) Exploitation: Extracting the minerals from the mines.


6


Environmental Impacts of Extracting and Usage of Mineral Resources:The environmental effects of extracting using mineral resources depend on such

as Ore Quality Mining Procedures Local Hydrological Conditions Climatic Conditions Rock types etc

Impacts:

Degradation of land i,e, the top soil as well as the plants are removed from the mining area.

Ground water contamination.

Pollution of surface water resources due to release of harmful trace elements.

Severe adverse impacts on the growth of plants.

Desertification includes loss of flora & fauna.

Adverse impacts on historical monuments.

Physical changes in the land, soil, water and air associated with mining activities directly and indirectly affect the biological environment.

Occupational health hazards.

Most of the miners suffer from various respiratory and skin diseases.

Destruction of the eco – system.

Noise Pollution.

Deregulation & defacing of landscape

Subsidence of land.


7


Control: Recycling. Designing of small equipments. Developing more efficient technologies. Finding new uses for glass, ceramics, plastics and synthetic fibers.

ENERGY RESOURCES

Introduction: Energy is the physical quantity, which can manifest it self as heat, as mechanical

work, as motion and in the binding of matter by nuclear (or) chemical forces.

Definition:Energy means capacity to do work (or) ability to do work, changing the physical

state of motion of an object.


8


Measurement of Energy:Fossil fuels provide heat energy which can be used for running the steam engines

and internal combustion processes, running of boilers provide mechanical energy to machinery to pull up the object and transfer of goods.Energy is measured in Joules, Ergs, Cal, K.Cal, BTU, Electron Volt, (EV), KWh (Kilo – Watt Hour).BTU = British Thermal Unit1 Erg = 10-7 J1 Cal = 4.184 J1 BTU = 1.506 JUses of Energy:Energy is used in different sectors for different forms such as Heat, Coal, Petrol, Natural Gas for different purposes like agricultural purposes, industrial purposes, Mining, transportation and lighting.

Classification of Energy Resources:Energy resources are classified as

a) Renewable Energy Resourcesb) Non – Renewable Energy Resources

a) Renewable Energy Resources:Renewable resources which can be regenerated continuously in nature and are inexhaustible. Renewable energy resources as solar energy, wind energy, hydel energy, bio – energy etc.

b) Non – Renewable Energy Resources:Non – Renewable Energy Resources of energy are those which are not replaced (or) replenished by natural process. These resources are get depleted (or) exhausted by use.Ex: Coal, Petroleum, Natural Gas.Currently fossil fuels provides about 95% of all commercially used energy in the world. Renewable energy resources such as solar, wind, tidal energies provide 2.5% of power demands. These are available in limited amounts.

Annual Energy Consumption:The annual per capita of energy consumption ranges from 5 – 11 KW in

developed countries, where as it is 1 – 1.5 KW in developing countries like India. Energy consumption is several times linked with comfort and luxury in the daily life.

Alternative Energy Resources (Renewable Energy Resources):

a) Solar Energy:Solar energy is used instead of coal and nuclear power to produce electric power. Two variable methods which prove to be economical in this application are ‘Photo Voltaic Cells’ and ‘Solar Trough Collectors’. Sun is the ultimate source of energy either directly (or) indirectly for all sources of energy.


9


Solar Constant:The amount of energy is absorbed by the earth surface is approximately

1.4 KJ / Sec / m 2 . This value is known as ‘Solar Constant’.

Important Solar Harvesting Devices:a) Solar Water Heater Systemb) Solar Refrigeratorc) Solar Driersd) Solar Cookerse) Solar Green Housef) Solar Furnaceg) Solar Pondsh) Solar Desalination Systemi) Solar Photo Voltaic Cells

a) Solar Water Heater System:This system of water heating is commonly used in hotels, hospitals, hostels and guesthouses etc as well as domestic and industrial units.

b) Solar Refrigerators:Solar refrigerators are closely related to sir conditioning (or) general refrigerators. It is generally required for food preservation, storage of medicines & other biological products.

c) Solar Driers:Solar driers are generally used in agricultural fields for drying of grins, fruits, vegetables etc.


10


d) Solar Cookers:Solar cookers are used for cooking of food. This food gets cooked with the heat energy produced due to increased temperature inside the solar cooker.

Advantages: Solar cookers required neither fuel nor attention while cooking the food. No pollution. No over flowing of food. The biggest advantage of solar cooker is the nutritional value of cooked

food is very high. Maintenance cost is negligible.

Disadvantages: Food cannot be cooked at night times (or) rainy seasons and cloudy days. Chapattis cannot cook in solar cookers. Time taking process.

e) Solar Green House:A green house is a completely closed structure covered with transparent material; the material may be plastic (or) glass. It acts as ‘solar energy collector’.Solar green houses especially used for the growth of delicate plants (or) sensitive plants preferably in rainy and winter season which gives enough warm conditions for sustaining of life of plants.It allows only short wave solar radiations which are useful for the growth of plants; it reflects long wave radiations which are harmful for the growth of plants.


11


f) Solar Furnaces:Solar furnaces provide a means of generating extremely high temperatures up to around 3,500 0 C under very clean conditions .

g) Solar Ponds:Solar ponds are large – area brine ponds generally used for production of electricity.

Zones (or) Layers of Solar Pond:I. Top Zone

II. Middle ZoneIII. Bottom Zone

Top Zone:Top zone of the solar pond is called as ‘Surface Zone’(or) ‘Absorbent Zone’.It absorbs the solar radiations and transmits these radiations to bottom zone

through middle zone.

Middle Zone:Middle zone of the solar pond is called as ‘Transparent Insulator Zone’.It separates the bottom zone from the top zone. It permits the sunlight to reach

the bottom zone.

Bottom Zone: Bottom zone of the solar pond is called as ‘Storage Zone’.


12


h) Solar Desalination System:Solar desalination system is an effective and economical method for obtaining of distilled water from saline water.

Procedure:Saline water is placed inside the solar still and painted inside with black material.

Solar still is covered with glass material and total still is placed in sun light. Solar radiations are absorbed by the black surface and transmit through glass cover and heat the water by 10 – 200 C, causing it into evaporates. The vapour condenses as pure distilled water on the undesirable cover and flows in to condensate collection channel. On a gud sunny day an out put of about 2.5 – 3 L of distilled water can be obtained. It is effective & economically viable method. This system is mainly used in water scarcity areas.Per day we can collect 2.5 – 3 L of distilled water. This method is mainly used for collection of distilled water from saline water.

i) Solar Photo – Voltaic Cells (SPV):Solar Photo Voltaic Cells converts the solar energy into Direct Current (DC) (or) Electrical Energy. This electrical energy can either be used as it is (or) can be stored in the battery. This stored electrical energy then can be used at night.

Applications of Solar Photo Voltaic Cells:SPV can be used for a number of applications such as

Domestic Lighting Street Lighting Village Electrification Water Pumping Desalination of Salty Water Railway Signals etc.


13


WIND ENERGY:Introduction:

The fast motion of air is called as ‘Wind’. Wind energy can be harvested by making use of windmills. The annual wind power potential of our country is estimated to be 20,000 MW, but currently we are generating only 1020 MW of wind energy per annum. The largest wind farm of our country is located near Kanya Kumari; in Tamil nadu state has the capacity of 380 MW.

Advantages of Wind Energy: It is renewable source of energy. It is eco – friendly source of energy. No pollution. The power generation is cheaper.

Disadvantages of Wind Energy: It depends on air, so it is irregular, some times dangerous. It will not work at low – velocity ranges.

WIND MILL:Introduction:

A windmill is consists of Rotor, Blades, Gear Box, Generator, and Distribution System etc. Wind speed is depends on height of the wind mill (or) tower of the windmill. Wind speeds are measured at a height of 10m. At a height of 60m windmill starts to generate 30 – 60% of power.


14


Factors:Three factors determine the output of energy from the windmill

Wind speed. Size & shape of the blade. Over all conversion efficiency of rotor.

Types of Windmills:Windmills are divided in to two types

Horizontal Axis Windmills Vertical Axis Windmills

a) Horizontal Axis Windmills:Horizontal axis windmills are three types

1. Multi Bladed Windmill2. Sail type Windmill3. Propeller type Windmill

b) Vertical Axis Windmills:Vertical axis windmills are two types

1. Savonious Windmill2. Darrier Windmill

a) Horizontal Axis Windmills:

1. Multi Bladed Windmill: Blades are made from sheet metal (Al). These rotors have high strength. They have good power efficiency, high starting torque and add advantage of

simplicity and low cost.

2. Sail type Windmill: Blades are made from sheet metal (Al). Blade surface is made from Cloth, Nylon, Plastic arranged as mast & pole (or)

Sail wings.


15


Conversion of Energy in a Windmill:Windmill can convert 60% of kinetic energy (wind energy) into mechanical

energy, but on average only 30 – 40% of available mechanical energy is converted into electricity.

Vertical Axis Windmill:Savonious Windmill

Savonious windmill was developed by S.J,Savonious in 1920.

Advantages: It eliminates excessive power requirements. It works even at low velocity ranges. Cost of vertical axis windmill is very low. It has simple in structure.

Disadvantages:This type of machine is too solid and more weight.

Comparison between horizontal axis windmill and vertical axis windmill:The design of vertical windmill are simple than horizontal axis windmill. Horizontal

axis windmill have several advantages than vertical axis windmill. Horizontal axis windmills are used in different sectors like electricity production and water pumping purposes, where as vertical axis windmills are used only for power generation.

Wind Pumps:Wind pumps are used for water pumping. Generally wind pumps are used in agricultural sectors, a forestation, domestic purposes etc

Wind Energy Conversion Systems:Wind energy system converts the kinetic energy into useful form of power.

Wind Turbines:Wind Turbines are two types

a) Single Wind Turbine (or) Single Wind Farmb) Cluster wind Turbine (or) Cluster Wind Farm

Single Wind Turbine:It is also called as ‘Aero Generator’. Aero Generators are used for storage of wind energy in batteries.

Cluster Wind Turbine:These are group of wind turbines, called as ‘Clusters’. Wind turbines can be constructed in side the sea (or) out side the sea.

Cluster Wind Turbines are two types


16


Off – shore Wind Turbine On – Shore Wind Turbine

1. Off – Shore Wind Turbine:Construction of wind turbine in side the sea called as ‘Off – Shore Wind Turbine’.

2. On – Shore Wind Turbine:Construction of wind turbine out side sea is called as ‘On – Shore Wind Turbine’.

BIOMASS:Introduction:

Biomass is organic material, which has stored sunlight in the form of chemical energy. Biomass fuels include wood, wood waste, straw, manure, sugarcane, and many other by products from variety agricultural processes

Advantages of bio – Mass: Storage possible. Transportation possible. It is renewable. High-energy rich fuels can be obtained. Low capital input required. Technology mostly available. It is ecologically safe. It doesn’t increase CO2 content of the atmosphere.

Disadvantages: Land & water use competition. Collecting & storing is bulky & costly. Supply uncertainty initially. Costs uncertain. Fertilizer, soil, water required. Low conversion efficiency.

BIO – GAS:Introduction:

Bio – Gas originates from the bacteria in the process of biodegradation of organic material under anaerobic conditions.

Methane Content in the Atmosphere:Every year 590 – 880 million tones of methane is released into the environment

throughout the world through microbial activity.

Methanogens:Methane producing bacteria’s are called as ‘Methanogens’. This micro –

organisms are under goes anaerobic digestion and releases methane gas.

Bio – Gas Process:


17


The whole bio – gas process can be divided into three steps. Hydrolysis Acidification Methanogenisis

Three types of bacteria are involved.Hydrolysis:

In this first step the bacteria converts the complex organic material into the simple organic compounds. This reaction occurs in the presence of aerobic condition.Ex: Poly Saccharides are converted into monosaccharides, proteins are converted into peptides & amino acids.

Acidification:Acid – Producing bacteria, involved in acidification. In this process bacteria convert the intermediates of fermenting bacteria into acetic acid, hydrogen and carbon – di – oxide. The acid producing bacteria creates anaerobic condition which is essential for the methane producing micro – organisms. Micro – organisms reduce the compounds with a low molecular weight into alcohols, organic acids, amino acids, carbon di oxide, hydrogen sulphide and traces of methane.

Sources of Bio – Gas:Cattle Dung / Cow DungOther sources are

Goat Dung Pig Dung Chicken Droppings Buffalos Dung etc

Bio – Gas Production: 1 Kg Cattle Dung - 40 Lt bio – gas 1 Kg Buffalo Dung – 30 Lt bio – gas 1 Kg Chicken Droppings – 70 Lt bio – gas 1 Kg Pig Dung – 60 Lt bio – gas

Composition and Percentage of Bio – Gas:Bio – gas contains60% of Methane (CH4)40% of CO2 and Trace quantities of H2S & N2 gases.

Calorific Value of Bio – Gas:The calorific value of bio – gas is more than 5,000 K.Cal / m 3 . The calorific value is mainly depends on Carbon – di – oxide content. As carbon – di – oxide content increases in bio – gas, the calorific value decreases.

CO2 1/ Calorific Value


18


Factors affecting Bio – Gas Production:Two important factors play an important role in bio – gas production.

Temperature Pressure

These two factors effect the volume / strength of bio – gas calorific Value. Water vapour content of organic material.

Applications of bio – gas:Biogas is a lean and clean gas. Bio – gas can be used in different sectors for different purposes.

Gas Cookers / Gas Stoves Bio gas lamps Radiant Heaters Incubators Refrigerators Engines

Gas Cookers / Stoves: Simple and easy operations Easy to clean Easy to repair Acceptable cost Good burning properties Attractive appearances.

Efficiency of Bio – Gas:The calorific value of bio – gas is more than 5000 K.Cal / m 3 . This calorific

efficiency of using bio gas is 55% in stoves, 24% in engines, but only 3% in lamps.

Benefits of Bio – Gas: It is renewable source of energy. It is eco – friendly source of energy. No pollution. It is alternative source of energy. Manure / Dung can be used as bio – fertilizer. Savings in the cost of disposal. Time saved.

Benefits of bio – gas Technology: Production of energy (heat, light, electricity). Transformation of organic wastes into high quality fertilizer. Improvement of hygienic conditions through reduction of pathogens, worm eggs

and flies. Environmental advantages through protection of soil, water, air and woody

vegetation. Reduction workload, mainly for women in fire wood collection and cooking.


19


Ocean Thermal Energy Conversion (OTEC):The oceans collect and store huge quantities of solar radiations in the form of

heat. Most of the heat is stored on the surface of the sea water while the temperature of deep waters is very low.

Using this temperature difference, we can convert the heat energy into electricity. Many low boiling liquids like ammonia, butane and freons are used to extracting the heat and converting it to electricity.

HYDEL ENERGY:Introduction:

Hydel means water, energy is produced from water resources. The energy in the flowing water can be used to produce electricity. The total world hydel energy potential is 44,000 Tetra – Watt Thousands / Years. It is equivalent to 5.5 billion tones of coal.The first hydro power project in India was installed in 1897 in Darjeeling, it had the capacity of 130 KW.

Limitations: Initial capital investment is high. Construction takes more time. Agricultural lands and forest are lost. Large populations are displaced. The high rate of Siltation. The eco – system in the dam area is adversely affected.

GEO – THERMAL ENERGY RESOURCES:Introduction:

Geo means Earth, Thermal means heat, the total term geo – thermal energy refers that energy is produced from earth resources.

Core: It is inner layer of the earth. It contains two materials namely Fe & Ni elements. It is in Liquid state. It contains very high temperature nearly 6,0000 C. Some times, in some regions the material present in the core breaks the earth and

produces volcanoes (or) some times the materials comes through the mantle and reaches the very nearer to the surfaces and produces heat.

HYDROGEN ENERGY:Introduction:

Hydrogen is clean, non – polluting energy rich fuel. The major problem is fire and explosion hazard. Hydrogen is combustible gas, in combustion process it combines with oxygen and forms water and releases large amount of energy. The amount of energy is released from one gram of lightest element is 1.25 X 10 5 Joules. It is equal to one gram of petrol.

Hydrogen as Primary Fuel:


20


One gallon (4.55 L) of hydrogen has energy content of 52,000 BTU. It can be produced from electrolysis process and can be converted into electricity in devices called as ‘Fuel Cells’. The raw material for hydrogen production is water, which is available in abundance. Hydrogen is completely renewable fuel. It can be stored in gaseous form, in liquid form in the form of metal hydride (or) absorbed in active carbon.

Methods of Hydrogen Production:a) Direct thermal decomposition of water at temperature exceeding 17500C.b) Electrolysis of waterc) Photolysis (or) direct extraction of hydrogen from water using sunlight as an

energy source.

Fuel Cell:A fuel cell is an ‘Electro Chemical Energy Conversion Device’ that converts

hydrogen and oxygen into water and producing electricity, heat. It is very much like a battery that can be recharged while drawing power from it. Here fuel cells are recharged with hydrogen and oxygen instead of electricity.

A fuel cell consists of two electrodes and an electrolyte. Oxygen passes over one electrode and hydrogen passes over another electrode.

Hydrogen splits into electron and proton. Protons are passes through electrolyte and reaches cathode electrode. Here oxygen is present and reacts with hydrogen and forms water and produces electricity and heat etc. electrons are passes through electric circuit and generate electricity.

NON – RENEWABLE ENERGY RESOURCES:


21


Introduction:Non – renewable energy resources are like Coal, Petroleum, Natural Gas and

Nuclear Fuels.

Coal:There are mainly three types of coal is present in environment.

a) Anthracite Coalb) Bituminous Coalc) Lignite

Anthracite Coal: It is hard coal. It has maximum carbon content – 90%. Calorific Value is 8,700 K. Cal.

Bituminous Coal: It is soft coal. It has carbon content of 80%. Calorific value is less than 8,000 K. Cal

Lignite: It is brown coal. Carbon content in lignite is 70%.

Coal States of India:The important coal states of India are Jharkhand, Orissa, Madhya Pradesh,

Andhra Pradesh & Maharastra etc. Anthracite coal is occurs only in Jammu & Kashmir. When coal is burnt it produces CO 2, which is a green house gas responsible for causing enhanced global warming. Coal also contains impurities like sulphur and there fore as it burns the smoke contains toxic gases like oxides of sulphur and nitrogen.

PETROLEUM:Total 13 countries in the world having 67% of the petroleum reserves. Crude

petroleum is a complex mixture of alkane hydrocarbons. Hence it has to be purified and refined by the process of ‘Fractional Distillation’. During this process, different constituents separate out at different temperatures. We get a variety of products from this, namely petroleum gas, kerosene, petrol, diesel, fuel oil, lubricating oil, paraffin wax, asphalt, plastic etc.

Liquified Petroleum Gas:The main component of petroleum is butane and other components are propane &

ethane. The petroleum gas is easily converted into liquefied petroleum from under pressure as LPG. It is odour less gas, but the LPG in our domestic gas cylinder gives a foul smell. This is infact, due to ethyl Mercaptans, a foul smelling gas, add to LPG, so that any leakage of LPG from the cylinder can be detected instantaneously.


22


NATURAL GAS:Introduction:

It is mainly composed of Methane (95%) with small amount of propane and ethane.

It is fossil fuel. It is cleanest fossil fuel. It can be easily transported through pipelines. It has high calorific value of about 50 KJ / G and burns without any smoke. Natural gas is used as domestic fuel and industrial fuel. It is used as fuel in power plants to generate electricity. It is used as source of hydrogen gas in fertilizer industry. It is used as source of carbon in tyre industry.

Types of Natural Gas:a) Compressed Natural Gas (CNG)b) Synthetic Natural Gas (SNG)

a) Compressed Natural Gas (CNG): It is used as an alternative source to petrol and diesel for transport of

vehicles. CNG reduces vehicular pollution.

b) Synthetic Natural Gas: It is mixture of Carbon monoxide and Hydrogen. It is a connecting link between a fossil fuel and substituted natural gas.

Advantages of Natural Gas: It eliminates the man power and mechanical power. Pollution Control Saves energy Higher boiling efficiency No storage yard required Better combustion.

Nuclear Energy: Nuclear Energy is known for its high destructive power as evidence from nuclear weapons. The nuclear energy can also be harnessed for providing commercial energy.Nuclear Energy (Power) Generation: Nuclear energy can be generated by two types of reaction.

a) Nuclear Fissionb) Nuclear Fusiona) Nuclear Fission: It is the nuclear change in which nucleus of certain isotopes

with large mass numbers are split into lighter nuclei on bombardment by neutrons and a large amount of energy is released through a chain reaction.


23


b) Nuclear Fusion: Here two isotopes of a light element are forced together at extremely high temperatures until they fuse to form a heavier nucleus releasing enormous energy in the process.

Conservation of Resources:Energy Resources:

Use public transportation, walk or riding a bicycle. Use stairs instead of elevators if you are not sick. Joining a car pool or driving a smaller or more energy efficient car. Insulate your house. Turn thermostats down in the winter & up in th summer. Create a wind break on the north side of your house. Use recycled glass metals & papers. Eat locally grown food in season. Buy locally made, long lasting materials. Use energy – efficient appliances, it can saves substantial amount of energy. Use paper saving devices.


24


LAND RESOURCES

Introduction:Land is the important major constituent of the lithosphere and is one of the main

components of natural environment besides air, water and plants. It forms about one – fifth of the earth’s surface, covering about 13, 393 million hectares and is the source of many materials essential to man & other organisms. Soil is a dynamic layer of earth’s crust which is constantly changing and developing. Soil formation takes place with the decomposition of rocks & minerals, sol properties like soil texture, structure, permeability, soil water, porosity, soil pH, organic & inorganic content, cation exchange capacity etc.About 200 – 1000 years are needed for the formation of one inch or 2.5 cm of soil, depending upon the climate and the soil type. But when rate of erosion is faster than rate of removal, then the soil becomes a non – renewable resource.

Composition of the Earth:

Earth is made up more than 100 different elements. The important elements and their composition is as underAluminum – 8.13%, Ca – 6.63%, Fe – 5.101%, Mg – 2.09%, O2 – 49.5%, K – 2.62% & Si – 27.72%.

Lithosphere:The study of soil (or) study of the earth (or) rocks is called as ‘Lithosphere’.

Soil as a Natural Resource: Soil is a renewable natural resource. It plays a vital role in the determination of the quality and composition of the biosphere. It is a collection of natural bodies on the earth’s surface containing living as well as non – living components.

The surface layer of the land is called ‘Soil’. About 4/5 th of the land area is covered by soils. The word soil is derived from the ‘Latin’ word called ‘Solum’ meaning ‘Upper

Crust of the Earth’ (or) ‘Earthy Material’. Soil consists of living as well as non – living matter and capable of supporting

plants.

Layers of the Earth (or) Lithosphere:Earth id divided into three important layers.a) Coreb) Mantle

c) Crust (or) Earth Crust


25


a) Core: It is the inner layer of the earth. It consists of two elements namely Ni & Fe. It is in liquid state. The temperature of the core is around 6,000 0 C. The total diameter of the core is about 2900 Kms. Core is divided into two types (a) Inner Core (b) Outer Core

b) Mantle: It is the middle layer of the earth. It consists of two elements namely Al & Si. It is in semi – solid state. Diameter of mantle is about 2500 Kms. Mantle is divided into two types (a) Upper Mantle (b) Lower Mantle

c) Crust (or) Earth Crust: It is outer most layer of the earth. It is in solid state. The rest of the elements are present in crust (or) Earth Crust . The diameter of crust is 8 to 40 Kms from the mantle . Crust is divide into two types (a) Lower Crust (b) Upper Crust.

Formation of Soil:Soil is formed due to the ‘Weathering of Rocks (or) Minerals’.

Weathering:Conversion of rocks into the soil particles through physical, chemical and

biological processes is called as ‘Weathering’.

Types of Weathering:Weathering is divided into three types

a) Physical Weatheringb) Chemical Weatheringc) Biological Weathering

a) Physical Weathering:Conversion of rocks into the soil particles through physical changes called as ‘Physical Weathering’. Four different physical factors are involved in physical weathering like Temperature, Humidity, Rainfall, Pressure and sometimes local Climatic conditions. It includes heating and cooling of rocks , wetting and drying of rocks.

b) Chemical Weathering:Conversion of rocks into the soil particles through chemical changes is called as ‘Chemical Weathering’. Four different chemical processes are involved in chemical weathering like Hydrolysis, Hydration, Oxidation & Reduction etc.Hydration means addition of water, hydrolysis means reaction with water, oxidation means loss of electrons, reduction means gain of electrons etc.


26


c) Biological Weathering:Conversion of rocks into the soil particles through biological changes is called as ‘Biological weathering’.

Important Functions of Soil:

It provides mechanical support to the plants growth. It acts as ‘store house of mineral matter & organic matter’. It acts as ‘reservoir of water’. Soil consists of macro & micro nutrients which are help for the growth of plants,

animals and microbes. Soil contains a wide variety of bacteria, fungi, protozoa and many other microbes

which help in the decomposition and mineralization of organic & regeneration of nutrients.

Neutral pH. Increases water holding capacity. Good aeration. Soil also helps in preventing excessive leaching of nutrient ions, which

maintaining proper pH.

Soil Profile:Horizon – O, Horizon – A, Horizon – B, & Horizon – C are collectively called as

‘Soil Profile’.

Horizon – O:Surface layer of the top soil consists of bacteria, fungi, protozoa, viruses, debris,

freshly fallen leaves, organic and mineral matter collectively called as ‘Horizon - O’.

Horizon – A:Top soil is also called as ‘Horizon - A’. out of 45% of mineral matter nearly 35%

of mineral matter is present in top soil.

Horizon – B:Middle soil is called as ‘Horizon - B’. out of 5% of organic matter nearly 1% of

organic matter is present in middle soils, remaining 4% is present in top soils.

Horizon – C:Air, water is present in top, middle and bottom soils. Bottom soils are called as

‘Horizon - C’.


27


Soil:Soil consists of living & non – living components which are helpful for the

growth of plants.

Living Components of Soil:Living organisms are Bacteria, Viruses, Fungi and Protozoa which are helpful for

decomposition of organic matter and mineralization of inorganic matter.

Non – Living Components:

Non – Living Components areSoil consists of 45% - Inorganic Matter

5% - Organic Matter25% - Air25% - Water.

Inorganic Matter:Inorganic matter is also called as ‘Mineral Matter’. Out of 45% of inorganic

matter nearly 35% of the inorganic matter is present in top soil, 10% of inorganic matter is present in middle soils. Inorganic matter is divided into two types(a) Chief Inorganic Elements (b) Ordinary Inorganic Elements.

(a) Chief Inorganic Elements:Plant requires large quantities of chief inorganic elements for their growth. Nitrogen, Phosphorus, Potassium are large in quantities. These elements are called as ‘Chief Inorganic Elements’.


28


(b) Ordinary Inorganic Elements:Plant requires small quantities of ordinary inorganic elements for their growth. The ordinary inorganic elements are Ca, Zn, Fe, Mg, S, Co, Mn, Mb etc are small in quantities called as ‘Ordinary Inorganic Elements’.

Mineralization:The process of conversion of mineral matter into essential nutrients through the

microbial activity called as ‘Mineralization’.

Organic Matter:Soil consists of 5% of organic matter, out this 5% of organic matter, 4% of

organic matter is present in top soils, 1% of organic matter is present in middle soils. Organic matter is present in various forms in soils, present in the form of Amino Acids, Proteins, Peptides, Sugars, Latex, Gums, Resins etc. Due to the presence of all these compounds in soil, the soil gets black colour. This black colour of the soil is called as ‘Humus’. Both organic and inorganic matter are acts as nutrients helpful for the growth of plants.

Air:Soil consists of 25% of air, present in top, middle and bottom soils. This is

helpful for photosynthesis process and growth of plants.

Water:Soil consists of 25% of water, present in top, middle and bottom soils, helpful for

the growth of the plants and metabolic activities of plants.

Humus:The process of formation of humus is called as ‘Humification’.

Soil gets black colour due to the presence of humus. Humus is divided into three types.a) Raw Humusb) Morc) Mull

a) Raw Humus: Partial decomposed organic material is called ‘Raw Humus’.b) Mor: outer most layer of partial & complete decomposed organic material.c) Mull: Complete decomposed organic material is called as ‘Mull’.

Important Characteristics of Humus: Improves the physical conditions of soil. Tend to increase water holding capacity. Source of Nutrients. Major source of energy to plants. Neutral pH. Maintains good aeration.


29


Classification of Soils:Based on colour and chemical composition, Indian soils are classified into

different types.a) Black Soilsb) Red Soilsc) Brown Soilsd) Whitish Soilse) Blue Soilsf) Lato Soilsg) Desert Soilsh) Mountain Soils

a) Black Soils:Black colour of the soil is due to the presence of humus (or) organic matter.

b) Red Soils:Red colour of the soils is due to the presence of Iron Compounds, Iron is present in Oxidation state.

c) Brown Soils:Brown colour of the soil, is due to the presence of Iron compounds, Iron is present in Reduction state.

d) Whitish Soils:White colour of the soil is due to the presence of Salts, the salt may be Sodium Salt (or) Potassium Salt etc.

e) Blue Soils:Blue colour of soil is due to the presence of Copper compounds.

f) Lato Soils:Lato soils are consists of Hydroxides of Al. and Hydroxides of Si etc.

g) Desert Soil:Desert soils are occurs (or) present in desert region. Low quantities of Loam soils are present in desert. Due to the presence of Loam soils in desert soils, it encourages the growth of desert Plants.Ex: Cactus Plant

h) Mountain soils:All type of soils are present (or) mixed in mountain soils. Generally occurs in mountain regions.

Types of Indian Soil:Based on the size of the soil particle, Indian soils are classified into three types.

a) Clayey Soilsb) Sandy Soilsc) Loam Soils

a) Clayey Soils: The size of the clay particle is less than 0.002 mm. It will not allow the free movement of air & water. It has poor inter spaces .


30


It is not suitable for the growth of the plant species . It can hold more water .

b) Sandy Soils: These are loose & dry soil Particles . These have small inter spaces. Low nutrient content & moisture content. Unsuitable for the growth of plants .

c) Loam Soils: The size of the Loam particle is greater than 0.002 mm. It has good moisture and nutrient content. Neutral pH. Suitable for the growth of plants. It consists of equal quantities of Clayey, Sandy and Loam Particles .

Properties of Soil:Soil posses many characteristics physical properties.

a) Densityb) Porosityc) Temperatured) Watere) Air

a) Density:An average density of soil 2.65 mg / L. Density of soil varies greatly depending upon the degree of weathering. As weathering rate increases, the density of particle decreases, as the rate of weathering decreases the size of the particle increases.

b) Porosity:The spaces present between soil particles in a given volume of sample are called as ‘Pore Spaces’.

Types of Pore Spaces:Pore Spaces are two types (a) Micro – Pore Spaces (b) Macro – Pore Spaces

a) Micro – Pore Spaces: Micro – Pore spaces are called as ‘Capillary Pore Spaces’. The spaces present between soil particles is very less. It can hold more water and it restricts the movement of air and water.

b) Macro – Pore Spaces: Macro – pore spaces are called as ‘Non – Capillary Pore Spaces’. It allows free movement of air and water.


31


c) Temperature:Average temperature in soil is 29 – 34 0 C, between this temperature range any soil

micro – organism can survive.

Air:Soil consists of 25% of air, present in top, middle and bottom soils.

Water:Soil consists of 25% of water, present in top, middle and bottom soils .

Main purposes of Land:The various purposes for which land can be used include

Agriculture Horticulture Industrialization Human dwellings. Waste Disposal. Forest etc.

Land Degradation:Degradation refers loss of biological productivity (or) loss of originality of soil.

Causes of Soil Degradation:The following are main causes of soil degradation.

Soil erosion Salinity Water logging Over grazing Agriculture Industrialization Land slides Urbanization Desertification etc

a) Soil Erosion:Soil erosion is defined as movement of soil components. Especially surface litter (or) top soil from one place to another place. It refers to the loss of removal of the superficial layer of the soil by the action of wind (or) air. Soil erosion leads to degradation of fertility as well as loss of quantity of soil.

b) Salination:Salination includes to increase in the concentrations of soluble salts in the soil. The high concentrations of salts in soil severely affects on crop production.


32


c) Agriculture:Most of the agricultural practices are harmful to soil. Modern agricultural practices are shows adverse impacts on the growth of the plants, animals and micro – organisms of soils.

d) Industrialization:Industries are pollute soils. Industries releases enormous amounts of effluents and wastes into soil, it badly effects on quality of soil.

e) Deforestation:Deforestation is a process of land degradation that leads to desert formation.

f) Urbanization:Human activities are responsible for land degradation of forests, crop lands and grass lands.

g) Landslides:Human activities such as construction of road & railway lines, canals, dams, reservoirs have affected the stability of hill slopes.

h) Soil Pollutants:Various types of soil pollutants such as pesticides, chemicals, radio – active elements, industrial wastes, plastics, tin – cans have adverse impact on the physical, chemical and biological properties of soil and hence reduces its productivity.

i) Water Logging: It may be due to surface flooding or due to high water table. The productivity of water – logged soil is severely affected reduced due to lesser availability of oxygen for the respiration of plants.

j) Desertification: It is a slow process of land degradation that leads to desert formation. Desert was formed by the degradation of thousands of hectares of productive land.

Pattern of Land Distribution in India: The pattern of land use varies from country to country. In India, more than two – fifth land is agricultural land. Agriculture – 43.6% Grass Lands – 15% Cultivable Lands – 12.2% Forests - 10.7% Urban Land - 5.3% Uncultivable Lands – 9%. Permanent Pastures & Meadows – 14.6% Barren & Uncultivable Waste Lands – 8.4%

Soil Erosion: It can be defined as the process by which rock fragments and soil are detached from the original site, transported and then eventually deposited at some new locality. It is comprehensive natural process of detachment and


33


removal of loosened soil materials by exo genetic processes. It is increased due to agricultural development, construction and strip – mining activities.Def: The slow movement of the fertile top soil and disturbances in the soil texture is called ‘Soil Erosion’.

Types: a) Normal or Geological Soil Erosion b) Accelerated Soil Erosion

Agents of Soil Erosion: (Fig)


34


WATER RESOURCES

Introduction:Water is vital natural resource which forms the basis of all life. It is an essential

component for survival of life. Water is present in three different forms in environment namely Solid, Liquid, Gaseous etc. Water covers 70% of the Earth’s surface, but only 3% of this is fresh water, of this, 2% is present as polar ice caps and only 1% is usuable water in rivers, lakes and subsoil aquifers. Only fraction of this can be actually used.

Hydrosphere: The study of water resources is called as ‘Hydrosphere’.

Different Forms of Water:Water is present in three different forms in environment, namely

(a) Solid Form Ex: Ice(b) Liquid Form Ex: Water(c) Gaseous Form Ex: Water Vapour

Concept:Out of 100% of water present in nature nearly

97% of water is present in Oceans. 2% of water is present in Polar Ice Caps in the form of Ice. 1% of water is available for Human Consumption.

Totally 97% + 2% = 99% of water, which is present in oceans & polar ice caps are unavailable for human consumption.

Out of this 1% of water, which is available for human consumption, nearly 0.5% of water is used for industrial, 0.2% of water is used for agricultural sector, 0.2% of water is used for domestic purposes and 0.1% of water is used for commercial purposes.

Personal Water use by an Indian Urban Resident:

S.No Use Liters / Person / Day

1 Drinking 3

2 Cooking 4

3 Bathing 20

4 Flushing 40

5 Washing Clothes 25


35


6 Cleaning Utensils 20

7 Gardening 25

Total 137

Possible Solution to the Water Crisis:The following is a list of possible solutions to the water crisis in India and elsewhere:

Reduce Demand Educate people to use less water Install water saving devices like self – closing taps, dual flush – toilets, spray taps

in sinks etc Use decentralized waste water recycling systems at homes, apartment blocks,

campuses and industries, using natural methods like planted filters. Adopt composting toilets to save water and also minimize the sewage disposal

problems. Adopt agricultural practices that require less water Replace water hungry crops by those that require less water. Promote crops that can tolerate salty water. Return the indigenous species that can withstand drought. Switch to organic and natural farming. Reduce industrial consumption through recycling, reuse and new water- efficient

technologies. Implement rain – water harvesting in urban and rural areas.

World Water Day: The international observance of World Water Day grew out of the 1992 United Nations Conference on Environment and Development (UNCED) in Rio – De – Janerio. In 1993, the Un assembly designated March 22 of each year as World Water Day. Each year, one of the UN agencies is in change of celebrating and promoting a new theme. While the theme for 2004 was ‘Water and Disasters’, which for 2005 is ‘Water for Life’.

Objectives: The Objective of World Water Day is to focus attention on the need to

Address the problems relating to drinking water supplies and Increase public awareness on the importance of conservation, preservation, and

protection of water resources and drinking water supplies.


36


Classification of Water Resources:Water bodies are divided into three main levels.

(a) Level – I Water Bodies (b) Level – II Water Bodies(c) Level – III Water Bodies

(a) Level – I Water Bodies:According to level – I Water bodies are divided into two types Lotic Water Bodies: Lotic means Running Water

Ex: Rivers, Oceans, Seas etc

Lentic Water Bodies: Lentic means Standard Water (or) Stagnant WatersEx: Lakes, Ponds, Reservoirs etc

(b) Level – II Water Bodies:According to level – II Water bodies are divided into two types Surface Water Bodies: Ex: Rivers, Oceans, Seas, Ponds, Lakes etc Ground Water Bodies: Ex: Wells, Bore Wells, Aquifers etc

(c) Level – III Water Bodies:According to level – III Water bodies are divided into two types Fresh Water Bodies: Ex: Rivers, Ponds, Lakes, Reservoirs etc Marine Water Bodies: Ex: Seas, Oceans etc

Uses of Water Resources:Water is used in different sectors for different purposes. Water is used in Industrial Sector Agricultural Sector Domestic Sector and Commercial Sector

Role of Water in different Sectors:At global level 70% of water is used for agriculture, 25% of water for industry

and only 5% of for domestic use. But in India, 90% of the water for agriculture, 7% for Industry and 3% for domestic purpose.

Atomic Structure of Water Molecules:Water molecule shows (or) posses bent structure with bond angle of 107.5 0 . When

one hydrogen atom reacts with two oxygen atoms forms water molecule. Water molecule shows bent structure due to the presence of lone pair of electrons and tetra hydel arrangement around O2.

UNIQUE PROPERTIES OF WATER: It exits as liquid over a wide range of temperature i,e, from 0 o to 100 o C. It has the highest specific heat, due to which it warms and cools down very slowly

without causing any shocks of temperature jerks to the aquatic life.


37


It is an excellent solvent for several nutrients, thus it can serve as a very good carrier of nutrients, including oxygen which is essential for life, but it can also dissolve various pollutants and became carrier of pathogenic micro – organisms.

It has high surface tension because of strong attractive forces between the molecules.

General Properties of Water:Water has three important properties

(a) Physical Properties(b) Chemical Properties(c) Biological Properties

(a) Physical Properties:Important physical properties are (i) Colour (ii) Temperature (iii) Turbidity

(i) Colour: Pure water doesn’t produce any colour and taste. Colour is measured by using of two units

a) Platinum – Cobalt Unitb) Hazen’s Unit

According to WHO standards for drinking water, the permissible limit / level of colour is 20 ppm. Colour is removed by using adsorption, Coagulation, and Filtration methods. Colour in water caused due to the presence of organic matter.

(ii) Temperature: An ideal temperature in water bodies is 4 – 100 C. 260C is undesirable, if water consists of 350 C that is unfit for human consumption.

(iii) Turbidity:

Turbidity is caused due to the presence of suspended & colloidal particles. Turbidity is measured by using two units

a) Nephlometric Turbidity Unitb) Jackson Turbidity Unit

(b) Chemical Properties:Chemical properties are (i) Total Solids (ii) Hardness (iii) pH (iv) Buffering Capacity (v) Salinity (vi) Chlorides (vii) Iron & Manganese etc

(i) Total Solids:Solids in water bodies are three typesa) Suspended Solidsb) Dissolved Solidsc) Colloidal Solids


38


(a) Suspended Solids: The Size of the Suspended particle is > 10 . (b) Dissolved Solids(c) Colloidal Solids: the Size of the colloidal particles are 0.01 - 10 .The maximum permissible limit of total solids is 750 mg/ L.

(ii) Hardness:Hardness of water is divided into two typesa) Temporary Hardness b) Permanent Hardness

a) Temporary Hardness: Water gets temporary hardness due to the presence of Carbonates & Bi – Carbonates of Calcium and Magnesium.

b) Permanent Hardness: Water gets permanent hardness due to the presence of Chlorides & Sulphates of Calcium & Magnesium.Hardness is generally expressed in ppm (or) gm / L.

(iii) pH:pH indicates the concentration of hydrogen ions in waterNeutral pH is 7Acidic pH is 0 – 7Alkaline pH is 7 – 14.

(iv) Buffering Capacity:It is the ability of water to maintain stable pH value even if acids (or) bases are added.

(v) Salinity:Salinity refers to the total amount of dissolved substances present in water.

(vi) Chlorides:Excessive Chloride in water is dangerous and unfit for use.The maximum permissible level of chlorides in drinking water 1 250 ppm.

(vii) Iron & Manganese:Brownish red colour in water is due to the presence of Iron & Manganese.It leads to the growth of microbial community and corrodes the water pipes.

Water Resources:

Water Resources are two typesa) Ground Water Resourcesb) Surface Water Resources

a) Ground Water Resources: About 9.86% of the total fresh water resources is in the form of ground water and it is about 35 – 50 times that of surface water supplies.

Aquifer:


39


A layer of sediment (or) rock that is highly permeable and contains water is called as ‘Aquifer’.

Types of Aquifers:Aquifers are two types

a) Good Aquiferb) Poor Aquifer

a) Good Aquifers: Layers of sand and gravel are ‘Good Aquifer’.

Classification of Aquifer:Aquifers are classified as

a) Unconfined Aquiferb) Confined Aquifer

a) Unconfined Aquifer: These are covered by permeable earth materials and are recharged by seeping down of from rainfall.b) Confined Aquifer: It is present between (or) sand witched between two

impermeable layers of rocks. The recharged area is hundreds of kilometers away from the location of well. Ground water is not Static. It moves very slow rate of about meter in annum.

Water Stress Countries:


40


When the countries per capita availability is less than 1700 cm is called as ‘Water Stress Country’. India is a water stress country with less rainfall of 1170 cm.The total land area = 3290 Lakh hectares.

Indian Water Resources:

Out of 100% of rainfallNearly 41% of water is lost in the form of evaporation 40% of water is lost in the form of run – off

10% of water is retained as Moisture 09% of water seeps in for recharging ground water

Out of this 40% of Run – Off / Flow water12% - Electricity Generation8% - Irrigation4% - Industrial Use2% - Domestic Purpose

Main Rivers in India:The important rivers in India are 4 types

a) Himalayan Water Systemsb) Deccan Water Systemsc) Coastal Water Systemsd) Other Water Systemsa) Himalayan Water Systems:

Ex: Ganga, Indus, Brahmaputra, Jhelum, Chinas, Ravi and Benas.b) Deccan Water Systems:

Ex: Nrmada, Tapati, Mahanadi, Godavari, Krishna, Periyarc) Coastal Water Systems:

Ex: All water bodies present near by coastal regiond) Other Water Systems:

Ex: Lakes, Streams

Water Resources of Andhra Pradesh:The normal annual rainfall is about 900mm. The total quantity of water received

through rainfall is 24.4 m ha / m41% through evaporation = 10.8 m ha / m40% through runoff = 9.8 m ha / m10% moisture = 2.4% m ha / m9% ground water recharge= 2.2m ha / m

Water poor Vs Water Rich Countries:

The top ten Water Rich Countries areIceland, Surinam, Narvey, Canada, Brazil, Gabon, New Guinea, Panama, and Guyana.


41


Water Poor Countries areKuwait, Egypt, Matla, Saudi Arabia, Maldives, Singapore, Israel, and Oman.

Water Usage in Different Sectors:At global level 70% of water is used for irrigation (or) agriculture, 25% of the

water for industry, 5% of water for domestic purpose.India:

But in India 90% of the water is used for agriculture, 7% of the water for Industry, and 3% of the water for domestic purposes.

Environmental Impacts of Large Dams:

The main Environmental impacts of large dams and hydel power projects could be classified into three categories.

Impacts within and around the area covered by the dams and reservoirs. Down – Stream effects caused by alteration in hydraulic regime. Regional effects in terms of over all aspects including resource use and socio –

economic aspects.

Problems related with Water Resources:Major problems related to water resources are

About 40% of the world’s population living in arid (or) Semi – arid region. These people have to spend substantial amount of time, energy and effort in obtaining water for domestic and agricultural use.

To meet the requirement of population, they are depending on surface water bodies, thus results in decreased the water table level and it also effects on ground water table.

Excessive irrigation practices in semi arid and arid regions can cause salt accumulation in soil, reduce crop productivity.

Continuous depletion of ground water along the coastal regions often leads to the movement of saline sea water into fresh water well spoiling their water quality.

Uses and Over Utilization of Ground Water and Surface Water:

Uses: water utilization varies from country to country. At global level, 70% of the water is used for agriculture, about 25% for industry and only 5% for domestic use. Industrialized countries use a greater percentage for industry. India uses 90% of its water for agriculture, 7% for industry and only 3% for domestic use. The total annual fresh water withdrawals today are estimated at 3800 cubic kilometers, twice as much as just 50 years ago. Studies indicate that a person needs a minimum of 20 to 40 lts of water per day fro drinking and sanitation. However, more than one billion people worldwide have no access of clean water and to many more water supplies are unreliable.India is expected to face critical levels of water stress by 2025, at the global level, 31 countries are already short of water and by 2025 there will be 48 countries facing serious water shortages. The Un has estimated that by the year 2050 4 billion people will be seriously affected by water shortages. Around 20 major cities in India face chronic or


42


interrupted water shortages. There are 100 countries that share the waters of 13 large rivers and lakes.

Effects of Over Utilization of Water Resources:a) Lowering of water tableb) Ground Water Subsidencec) Water Logging

a) Lowering of Water Table: Excessive use of water for drinking, irrigation, industrial and commercial

purposes has resulted in rapid depletion of water resources in various regions leading to lowering of water table and drying of well.

b) Ground Water Subsidence: When ground water withdrawal is more than the recharging rate, the sediments in aquifer become compacted. It is called ‘Ground Subsidence’. Huge economic losses may occur due to this phenomenon. The common problems are structural damage in buildings, fracture, and damage in pipes.

c) Water LoggingWhen excessive irrigation is done with brakish water it raises the water table

gradually leading to water logging and salinity problems.

Sustainable Water Management:Important Sustainable Water Management Methods are

Building several small reservoirs instead of few large dams. Developing small catchment areas and it protects the surrounding wetlands. Soil management. A forestation permits recharging of under ground water. Preventing leakage from dams & Canals. Preventing loss in municipal pipes. Excessive rain water harvesting in urban environment. Water conservation measures in agriculture, such as using drip irrigation. Desalination of sea water and ground water to make it fit for human consumption. Increases irrigation efficiency in agricultural lands by reducing water wastage. Reduction in domestic water wastage by constructing waste water treatment

plants and recycling the treated water.

Floods: Floods are due to rising water levels in earth as well as water bodies such as Rivers, Lakes etc, due to heavy rains. The effect of floods can be considerably reduced by the proper management. India is the worst flood affected country in the world. About 40 million hectares of nearly 1/8th of the India’s geo – graphical area is flood prone. Flood control measures involve construction of new embankments, drainage channels and a forestation. The satellite pictures of pre flood, flood and post flood along with other informatics contribute to the flood management process.


43


Floods are caused by both natural & anthropogenic factorsNatural factors are Siltation, LandslidesAnthropogenic factors are Deforestation, Overgrazing, Construction activities etc. Floods are important serious environmental hazards. Floods are usually occurs only in the rainy seasons. The loss of property was due to floods was 21 crores in 1951, which was increased to 1,130 crores in 1977.

Causes of Floods: Most of the human activities lead to the frequency and severity of flood. Some of them are

Heavy rain fall Construction of buildings Removing vegetation Deforestation Urbanization Earthquakes Paving roads and parking areas etc.

Effects of Floods: Erosion of top soil and vegetation Damage and loss to lands, houses and properties Spreading of endemic water borne diseases Silting of reservoirs and dams

Control of Flood: Construction of flood control dam Deepening, widening and straight tightening of streams Lining of streams Banning construction of buildings in flood – plains Converting flood – plains into wildlife habitat, parks and recreation areas.

Precaution Measures: Valuable house hold items, animals, and other necessary materials like food,

clothes, medicines etc should be shifted to safer places. Forecast, warnings and advices should be provided through media to educate and

aware people about the steps to be taken. Government agencies and NGO’s should be help the flood affected people by

providing public health services.

Drought:It has been a major problem in our country, especially in arid & semi – arid

regions. It is an unpredictable climatic condition and occurs due to the failure of one of more monsoons.


44


The problems of drought can be migrated by forestation programmes, which increase the content of air moisture, the amount of precipitation and the rate of rain water filtration when annual rainfall is below normal and less than evaporation drought conditions are created.

Dams:

Dams are developmental activities of nature, provides lot of economy to country but it also shows environmental adverse impacts. Dams play an important role in communities and economics that harness these water resources for their economic development. Big dams and river valley projects have multi – purpose uses and have been referred to as ‘Temples of Modern India’. However, these dams are also responsible for the destruction of vast areas of forests. India has more than 1550 large dams, the maximum being in the state of Maharastra (more than 600), followed by Gujarath (more than 250) and Madhya Pradesh (130). The highest one is ‘Tehri Dam’on River ‘Bhagirathi’in Uttarakhand and the largest in terms of capacity is ‘Bhakranagal dam’on river ‘Satluj’ in Himachala Pradesh

First dam was built in the year 1890 in China. Today 45,000 dams are present over all the world. Out of these

22,000 dams are constructed in China6400 dams are constructed in USA4300 dams are constructed in India1200 dams are constructed in Japan1000 dams are constructed in Spain

Dams are constructed for the purpose of National Development.

Advantages of Dams: Hydroelectric Generation Flood Control Agricultural Purpose Some time this dm water is used as drinking water in remote areas Navigation Irrigation to agricultural fields Reduces Soil Erosion Increases Water Holding Capacity.

Disadvantages of Dams: So much of water losses through evaporation, that results in increases the salt content in water bodies. Accumulation of salts shows adverse impacts on plants growth. Spread of infectious diseases. Increase the snails population. It requires lot of Space. It requires lot of man – power. Construction takes more time. Investment & Maintenance cost will be high.


45


If any damage is happens to dam, that water will be enter into the low lying areas. Loss of Flora & Fauna Deforestation, which leads to desertification Siltation Soil ErosionThe fragmentation & physical transformation of rivers Serious impacts on river – eco – systems. Social consequences of large dams due to displacement of people. Water Logging and Salinization of the surrounding lands. Disloding animal populations, damaging their habitat & cutting off their migratory routes. Disruption of fishing & waterway traffic.

ROLE OF AN INDIVIDUAL IN CONSERVATION OF RESOURCES:


46


Every individual has a major role in the conservation and equitable use of natural resources for sustainable life styles, without natural resources, the survival of human beings is impossible. Different natural resources like forest, water, soil, food, mineral and energy resources play a vital role in the development of a nation. How ever, over use of these resources in our modern society is resulting in fast depletion of these resources and several related problems.

Conservation of Water Resources: Turn – off the taps while brushing the teeth, washing the clothes, cleaning the

vessels etc. Take one bucket of water for bathing purpose, instead of using two or more

buckets. In washing machines fill the water only to the level required for your clothes. Water the plants in your kitchen garden and lawns in the evening when

evaporation losses are minimum. Use drip irrigation and sprinkler irrigation to improve irrigation efficiency and

reduce evaporation. Built rain water harvesting system in your house

Conservation of Energy: Turn off lights and fans when not in use. Use solar cooker for cooking purpose. Recycle and reuse glass, paper, plastic etc. Use low voltage lights. Use tube lights & energy saver bulbs as they consume less electricity. Switch – off Radio & Television when not required. Use pressure cookers, it saves 75% of energy. Use public transport, rather than using own vehicles Keeping the vessel covered with a lid during cooking, helps to cook faster, thus

saving 25% of energy.

Conservation of Soil: Use sprinkling & drip irrigation. Use green manure and mulch in the garden which will protect the soil. Grow different types of ornamental plants, herbs & trees in your gardens which

prevent soil erosion. Plant more trees it gives fresh air& protect the soil. Alternate planting helps to maintain the fertility.

Conservation of Forest: Prevention of forest loss (Deforestation) Extension of our forest wealth (a forestation & reforestation) Proper utilization of forest products. Reduce the consumption of forest and related products.


47


Boycott products of companies involved in deforestation, Compel Government and industry to make changes in the forest policies. Environmental conservation may be given importance in school curricula.

There fore an individual should Co operate with nature Try to sustain the ecological balance and bio-diversity of all species of earth Be responsible and minimize pollution and environmental degradation When an action is essential to meet a need , be sure it will not be harmful to other

living organisms Use non – renewable resources continuously Use high quality energy and Keep in mind the long – term effects on natural resources before altering nature

Sustainable development is based on carrying capacity and green accounting.

EQITABLE USE OF RESOURCES FOR SUSTAINABLE LIFE STYLES:

There is a big divide in the world as north and south, the more developed countries (MDC’s) and less developed countries (LDC’s), that haves and the have nots. The less developed does not mean that they are back ward as such they are culturally very rich or even much more developed, but economically they are less developed. The gap between the two is mainly because of population & resources.The More Developed Countries have only 22% of world population, where as it is 78% in Less Developed Countries, Natural Resources Consumption is 88% in Developed countries, it is only 12% in less developed, energy utilization is 73% in developed, 27% in less developed & per capita in con is 85% in more developed countries and 15% in less developed countries.The gap increasing between the two is increasing with time due to sharp increase in population in Less Developed Countries.

Consumerism refers to the consumption of resources by the people. Technological development has been a key factor in the development of human society right from the earlier (or) stone age to the present country. Modern technologies have enabled the main to produce a huge amounts of consumer items.

The manufacturing and the use of several luxurious items like refrigerators, sir – conditioners, spray can dispensers, DVD’s, VCD’s etc, release substantial quantity of Chloro Flouro carbons into atmosphere which deplete the life saving ozone layer of the stratosphere. The problem of disposal of several products of modern technologies such as used batteries, plastics, polythenes and many electronic goods has become headache even for the industrially developed and technologically advanced countries. Consumerism and waste generation varies from country to country. More the consumption of resources more is the waste generation and greater in the degradation of the environment.

Less Developed Countries (LCD’s):

In less developed countries (LCD’s) the number of people is very high, but per capita use of resources and waste generation are less.


48


More Developed Countries (MDC’s):

In more developed countries, the population size is small, but due to luxurious life styles, per capita use of resources and waste generation are very high.

Model of Paul Erlich & John Holdern:

This concept can be explained by using of Paul Erlich & John Holders (1972)Number of people X Per capita Use of Resources X Waste generated per unit of resource used = Over all Environmental Impact. The over all impact (Environmental Impact) of these two types of consumerism may be same (or) even greater.

Comparison of Consumerism & Waste Generation:

S.No Parameter Percent Global ValuesUSA INDIA

1 Population 4.7% 16%2 Production of

Goods21% 1%

3 Energy Use 25% 3%4 Pollutants / Wastes 25% 3%5 CFC’s Production 22% 0.7% The table shows that although the population of India is 3.4 times more than that of U.S.A. Its over all energy use and waste generation are less than 1/8 th that of USA. Thus more consumption leads to more waste generation


49

natural resources & its conservation

Documents

horizontal

horizontal

capillary

vertical axis

vertical axis

polar ice

macro pore

paul erlich