• March 22 every year as World Water Day
• Water is a natural resource that is vital for both plants and animals

Important Days

• World Wetland Day – Feb 2
• World Forest Day – March 21
• Earth Day – April 22
• World Environment Day – june 5
• Natural Resources Day – October 5
• Nature Conservation Day – Nov 5
• Rainwater is the purest form of water.

Glaciers, ice and snow

• Of the 3 percent of all water that is fresh, about three-fourths are tied up  in glaciers, ice caps and snowfields.
• They occur only at high altitudes or high latitudes

River Water

• The water in the rivers comes either from rainfall or melting of snow (glaciers) on the mountains.

Sea and Ocean water

• Oceans are a huge store of water Milllions of litres of water is presentinthem.
• But the water is salty and is not fit for any domestic or agricultural use.

Lake and Pond water                                       

• Lakes are inland depressions at hold standing fresh water almost all the year round.
• Ponds are small temporary or permanent bodies of shallow waier.
• They are still a minor component of total world water supply.
• The Saltiest of all is the Dead sea.

Solid:

• Ice is the solid form of water.
• It can be found in the atmosphere in the form of ice crystals, snow, ice pellets, hail, and frost.
• It is also found in the polar regions and high mountain peaks.

Liquid

• Rain and dew are formed of water droplets.
• Also liquid water covers three quarters of the surface of the earth in theform of lakes, rivers, and oceans.

Gas

• Water vapour is the gaseous form of water and exists as mist, fog, steam,and clouds.

Ground Water

• Precipitation in the form of rain or snow provides fresh water to our earth
• Most of the fresh water returns to the oceans through rivers.
• A small portion of rain water seeps into the soil and stored asunderground water.
• Underground water is also called an aquifer
• The top level of this underground water iscalled water table.
• If we dig a hole in the ground near water body we many find that the soil is moist.
• The moisture in the soil indicates the presence of water underground.
• If we dig deeper and deeper, we would reach a level where all the spacebetween particles of soil and gaps between rocks are filled with water.
• The upper limit of this layer is called the water table.
• The water table varies from and it may even change ata given place
• Water in the aquifers can usually be pumped out with the help of tube wells or hand pumps

DEPLETION OF WATER

Natural forces

• Scantly rainfall and hot winds are natural forces that may deplete thewater table. .

Human causes

• Deforestation, increased population, rapid urbanization, over-grazing bycattle, excess tapping of ground water are human causes.

Salt water intrusion

• Many parts ofthe world are losing fresh water sources due to saltwater intrusion.
• Over use of underground freshwater reservoirs often allows salt water tointrude into aquifers and affect water table.

Commercialization of water resources

• Some of the private companies suck a large quantity of water from river,and underground acquifers.

Sand grabbing from rivers

• Some rivers are deeply affected by sand grabbing. Eg. Palar river
• The monsoons bring heavy rains over most of the country between JuneandOctober.
• Only Tamil Nadu is the exception and receives over half of its rain in October and November.
• During the monsoon, water levels in rivers increases greatly  and may result in floods.
• India receives nearly 4 percent of the global precipitation and ranks 133 inthe world in terms of water availability per person per annum
• The total renewable water resources of India is estimated at 1,897 sqkmper annum. `

Scarcity of water

• Scarcity of water is defined as a situation where there is insufficient waterto satisfy normal requirements
• Though water is a renewable resource, we the humans are using it at afaster rate than it is being replenished.
• There are various factors contributing to the depletion of water table.
• Growing population has resulted in a growing demand for houses, offices,shops, roads etc.
• Increase in the number of industries.
• Water is used in almost every stage of production of thing that we use.
• Erratic monsoons result in excess use of groundwater thereby decreasingthe underground water.
• Uncontrolled use of bore well technology for extracting groundwater.
• Pollution of freshwater resources.
• This is due to the flow of untreated sewage from homes, toxic chemicalsfrom industries, and of pesticides and insecticides used by farmers into water bodies.
• No effective measures for water conservation
• The activity of collecting rainwater directly or recharging it into ground toimprove ground water storage in the acquifer is called rain waterharvesting

Rain water harvesting techniques

• There are two main techniques of rain water harvesting.
• Storage of rainwater on surface for future
• Recharge to ground water.

Advantages of rain water harvesting .

• Surface water is inadequate to meet our demand and we have to dependon ground water.
• Due to rapid urbanization, infiltration o the sub-oil hasdecreased drastically and recharging of ground waterv has diminished.
• Rainwater harvesting can reduce flooding in city streets
• Sea water intrusion in coastal areas can be arrested
• The ground water can be conserved
• Rainwater Harvesting can reduce top soil loss
• It can improve plant growth
• Icebergs are piece of glaciers that have drifted into the ocean and wouldotherwise melt and become salt water
• lcebergs are mostly white because the ice is full of tiny bubbles

DESALINATION OF SEA WATER

• Desalination is an artificial process by which saline water (sea water) isconverted to fresh water.
• The most common desalination processes are: 1. Distillation 2. Reverseosmosis.

Distillation

• The process in which both evaporation and condensation go side by sideis called distillation.

Reverse osmosis

• The process of forcing water under pressure through a semi permeablemembrane whose tiny pores allow water to pass but exclude most salts and minerals.
• The state government of Tamil Nadu has taken up a venture to convert sea water into potable water by the Reverse osmosis process to solve theproblem of scarcity of water at Chennai.

The Minjur desalination plant

• It is the largest desalination plant in India
• It is located in Kattupalli village near Minjur about 35km north ofChennai.
• The plant is established on 60 acre site at a cost of Rs.600 crore.
• It consists of 8,600 sea water reverse osmosis (RO) membranes to convertsea water into potable water.
• The RO technology of the plant produces 100 mld (million-litres-a-day) offreshwater from 273 million litres of sea water.
• The Minjur desalination plant supplies 100 mld of fresh water to theChennai Metro water at the rate of Rs.48.66 per 1000 litres
• The desalination plant serves potable water to an estimated population of5 lakh in Chennai.

The Nemmeli desalination plant

• The state Government has decided to alleviate the freshwater problems of sea water.
• Chennai Metropolitan Water Supply and Sewage Board (CMWSSB) is alsoconstructingdesalination plant at Nemmeli at a total cost of Rs.908.28crore.
• The planthascxapacity to convert 100 million litres per day as potable water from sea water
• Water from Nemmeli plant would be carried for 40 km to the city to be supplies to its residents.

SWEET WATER ON EARTH

• The 2006 Mumbai “ sweet” seawater. incident was a phenomenon during ffwhich the residents of Mumbai claimed that the water at MahimCreekhad suddenly turned ”sweet”.
• Mahim creek in India that polluted creeks in India that receives thousandsoftones of raw sewage and industrial waste every day.
• Within few hours of Mumbai “sweet” seawater incident, residentsofGujarat claimed that seawater at Teethal beach had turned sweet as well.
• Geologists at the Indian institute of Technology in Bombay offered theexplanation that water turning sweet is a natural phenomenon.
• Continuous rainfall over the preceding few days had caused a large poolof fresh water to accrue in an underground rock formation near to thecoast.
• Then this water discharged into tl1e sea as a large “plume” as fractures inthe rocks widened.
• Because of the differences in density, the discharged fresh water floatedon top of the saltwater of the sea and spread along the coast.

Conservation of plants and Animals

• Conservation can be defined in simple terms as the management ofresources in such a manner that the benefits accuse to largest  number ofpeople for the longest possible time without harming the natural or ecological balance
• All non-domesticated and non cultivated biota found in the naturalhabitat are termed wild life. .

Deforestation and Afforestation

• Afforestation has aimed at two kinds of forestry programmes such associal forestry and agro forestry.

Social Forestry

• In India Social forestry project was started in 1976 Its aim is to promote natural forests and create forests on unused lands
• Social forestry also aims at raising plantations by the common man so as to meet the growing demand for timber fuel wood fodder etc.,therdbyreducing the pressure on the traditional forest area

Agro Forestry

• Planting of trees in and around agricultural boundaries and on marginal private lands in combination with agricultural crops is known as agro-forestry
• Cutting down forest increases the amout of carbon-di oxide in the atmosphere which can affect climate and destroy the homes of many animals and plants
• So deforestation leads to soil erosion, irregular rainfall and global warming

Flora and Fauna

• India has a large variety of plants ,about 45,000 species in number .Of these 15,000 are flowering plants,1,676 bare algae;1940 are linches;12,480 are fung;64 are gymnosperms;2,843 are bryophytes;1,012 are pteridophytes
• India can be divided into eight distinct floristic regions
• The natural vegetation (plants) in aparticular area is termed as flora
• All the micro – organisms to macro – organisms (animals birds etc.) are termed as fauna

“Project Tiger” The populauon of Tiger (Pantheratigris) reduced from about 40 000 at the turn of the century about 1827 in 1972

• In 1 April 1973 Project Tiger was launched by Government of India, which resulted in increase population of tiger
• “Project Elephant” Elephant is the symbol of our National heritageanimal The population of Indian elephant Elephasmaximus is threatened due to poaching for ivory and habitat destruction
• An ambitious programme“Project Elephant”was launched by Ministry ofEnvironment and Forests which will focus on solving the problems ofhumans and elephants competing for the same habitat
• “Operation Rhino” Number of Indian rhino or one horned Rhinoceros (R.unicaris) are lost due to hunting and flood
• To protect the Indian species centrally sponsered rehabilitation programme was undertaken in Dudhwa National Park
• Lion Sanctuary” In 1972 a five year plan was proposed by the Government of Gujarat to protect this magnificent feline species in the Gir Sanctuary
• “Crocodile Breeding Project:Crocodile breeding and management project
• was launched by G 1975 for all the three endangered crocodile species namely the fresh water crocodile (Crocodyluspalustris), saltwater crocodile (Cricidylusporosus) and the rare gharial (Cravialisgangeticus)

Red Data Book

• International Union for Conservation of Nature and Natural Resources(IUCN) maintained the Red Data Book,

More to know

• NGC (National Green Corps) of the Ministry of Environment and Forests,Government of India.

National Animal – Tiger

National Bird – Peacock

National Flower – Lotus

National Fruit – Mango

National Tree- Banyan tree

Natioanl heritage-Elephant animal

• Lion, Tiger, Leopard, Snow leopard and Clouded leopard arein India Cheetahs became extinct in 1950s
• The breeding area of the famous olive Ridley’s turtle is the Coast of Orissa while the Hawksbill Turtles breed on the Coast of Tamil Nadu.
• Vedanthangal is a home for migratory birds, such as pintail ,garganey grey wagtail, blue-winged tail, common Sandpiper and some more.
• Salim Ali (1896 – 1987) Ornithologist,known as “the bird man of India”
• When a swarm of desert locust is on the move (A single swarm is about 50,000 million) eats 3000 tons of vegetation in one day
• The salmon fish travel up to 1500 miles(2400 km) from the sea to frest water for breeding
• Most of them die after breeding due to exhaustion.
• The Brazilian turtles travel up to 1250 miles (2000 km) in eight weeks time for breeding.
• Barren ground Caribou of North America travel over 3700 miles (5000 km) the longest annual migration of any mammal.

Wild Life Sanctuary and National Parks

• Sanctuaries: Sanctuaries are the places where the animals are well protected from any disturbance.
• Killing or capturing is highly prohibited. In our country there are about 500 sanctuaries

Some important Sanctuaries in Tamil Nadu

Some important National Parks in India

Threats to Biodiversity

• Current biodiversity is estimated at 10 to 100 million species, of which only 1.4 million have been formally catalogued.
• There are 12 mega diversity in the world. India is one of the 12 mega diversity centres of the world.
• The natural causes for the loss of biodiversity are floods, earthquakes, landslides, natural competition between species, lack of pollination anddiseases.
• There is an increased awareness among the people towards the conservation of ecologically sensitive areas
• The chipko movement initiated by SunderlalBahuguna stopped felling of trees in some parts of Himalayas.

 Structure of Living organisms

• Do you know which book was sold large number and paved way for the maximum criticism?
• It was the book titles ‘Origin of Species’which was published in the year 1859.       
• It was written by a Naturalist named Charles Darwin.
• Darwin sailed to several important islands of the world in the ship, H.M.S. Beagle, for more than 10 years and collected information.
• The study of microorganisms is
• Organisms differ in their character, size, nutrition, habit and habitat.This is called Bio-diversity.

Virus

• Virus cannot be seen with naked eye.
• It can be seen only through Electron microscope.
• Viruses cause a variety of diseases in plants and animals
• These infect us when we are not aware of them
• The branch of science that deals with viruses is virology

Beneficial activities of bacteria

• Curding of milk
• Decomposition of organic wastes into manure.
• Fermentation of idly and dosai flour.
• Some bacteria act as bio-fertilizer increasing the yield.
• 1Minute organisms called bacteria, which was discovered by Anton Van Leeuwenhoak in 1675.
• Chlamydomonas is a motile, unicellular plant.
• It is an alaga

Plant cell

• I have segmented body.
• My food is found mixed with soil.
• I am also known as “Friend of farmers”.
• I can produce manure.
• Who am I? Earthworm
• Worms like tape worm, hook worm ,Ascaris live in the human intestine
• They cause indigestion, frequent stomach ache ,dysentery and stomatitis
• It is good to intake properly cooked food and drink boiled water.
• Mosquito, housefly and bee are insects
• They can live in any part of the world
• They have compound eyes
• I have fish in my name , but not a fish.
• I have spiny skin but not a jack fruit.
• I have many colours, but not a rainbow.
• Even when broken into several pieces, I regenerate.
• Who am I? Star fish.
• My species are found on the land.
• I reproduce in the water.
• I am an amphibian but not a frog.
• I am a plant.
• Who am I? Moss
• Plants with seeds that can be separated into two cotyledons are called Dicotyledonous plants
• Plants with seeds that cannot be separated into two cotyledons are called monocotyledonous plants

Poisonous snakes

• Cobra
• Krait
• King Cobra
• Most of the snakes are non-poisonous except a few.
• Killing snakes leads to destruction of such species.
• Crocodiles have colour blindness.
• Tongue of chameleon is twice long as its body.
• King cobra is about 5.5m length.
• This is the most poisonous snake in the world
• A drop of this poison can kill 30 persons

Let us know

• Blue whale is the largest living organism
• Its weight is equal to weight of 22Elephants.
• Its heart is of a size of a samall car
• Dog was the first animal sent to space
• Its name was
• It was sent by soviet Russia
• In cows, sweat glands are found in the surface of nose.
• Man is the only living creature who can sleep with his back touching thefloor.
• Trunk of the Elephant is a modified form of its nose and upper lip.
• Tusks are the incisors of Elephant.
• The size of an Ostrich’s egg is equal to the size of 22 eggs of a hen

Fact File

• The bird that can fly forward, backward and sideways is the Humming bird.
• Birds like woodpecker and humming bird can’t walk,
• 0 Do you know which organism is not affected with any kind of diseases?
•  
• Camel’s milk cannot be converted into curd.
• The only living organism that cannot stretch out its tongue is crocodile.
• Lion’s roar can be heard to a distance of 5 km.
• Anaconda is the largest snake which will not lay eggs but give birth.
• Kangaroo rat survives without water for many days than camel.
• There are 17000 kinds of micro organisms in the human body.
• All polar bears habituated to use their left hand. ,
• Snail can pass through the edge of a sharp blade without getting hurt.
• Microorganisms are the living forms having more number of types on the earth.
• dot can be filled with 70,000 Amoebae

• Decomposed substances are used as manure for plants
• This is known as compositing
• The product formed by the worms by decomposing the wastes is termedas “vermicompost”.
• Recycling is the conversiuon of unwanted used products into useful products by decomposition
• In a day, earthworm consumes food equal to its weight
• Our water resources (pond,lake,river,canal and well) are polluted bysanitary industrial wastes
• ,insecticides and fertilizers and fertilizers.
• Because of this many diseases like cholera, typhoid, dysentery and jaundice are caused

Points to Remember:

• Waste products are classified into two- degradable and non-degradable.
• Degradable wastes can be converted into manure by using earthworm.
• Waste paper can be recycled and used again.
• The living organisms are affected by air, water, land and noise pollution.
• We can control pollution. .
• June 5~World Environment Day
• Sound is measured in decibel (dB).
• Human being can hear about 10 to 120 dB

ANIMALS IN DAILY LIFE

• The life on this planet Earth is sustained by plants and animals.
• Fishes are a good source of protein.
• Animals such as sheep, llama and goat provide us fur. The fur is processedinto wool.
• Animals which are used for ploughing and transporting are called draughtanimals.
• Wool: Wool is obtained from body haas sheep, llamaand goat. It is used to make sweaters, shawls,blankets,socks, hand gloves etc.
• Meat: Animals such as goat, sheep, pig,poultry birds, prawn, crab etc. yield flesh as food.
• Silk: Silk is obtained from silk worm and it is used for making silk clothes.
• Leather: The skin ofanimals such as goat, sheep, and cattle is used for manufacturing leather goods (bags,shoes, purses, suitcases, belts).
• Pearl: Pearl is a valuable gem obtained from pearl oysters and is used in making ornaments
• Lac: Some insects secrete a resin like substance called lac. It is used for making paints, varnish, printing inks and cosmetics,
• Milk: Animals like cows, buffaloes and goals give milk as food.
• Honey: Honey is obtained from honey bees. It is consumed along with foodand used in the preparation of certain medicines
• Egg: Poultry birds such as hen, duck, goose and turkey give us eggs as food.
• In 2004 December, some tribes that live in the forests of Andaman islandsnoticed the animals behaving in a different manner.

Wool

• Wool is a thick coat of hairy fibers (feece) obtained from sheep, goat, yak andother animals. It is a protein.
• The new wool harvest technology is called Bioclip.
• Yak wool is common in Tibet and Ladakh. Angora wool is obtained from in Jammu andKashmir.
• The underhair of Kashmiri goat (Pashmina) is woven into fne shawl. It isvery soft and expensive.

Processing of wool

• The process of cutting off the woolen feece of sheep with a thin layerof skin is called shearing.

Silk

• The best known type is obtained from the cocoon of larvae ofmulberry silk worm.
• Silk fabric was first developed ancient China.

Uses of Silk

• Silk is used for making silk clothes, parachutes, insulation coils for telephone and wireless receivers. _ `
• Pure silk is one of the finest natural fbres and is said to be time “queen offibres”.
• The rearing of silk worms for obtaining silk is called Sericulture.

The types of silk are

1. Mulberry silk
2. Tassar silk
3. Eri silk
4. Muga silk

• The most common silk is mulberry silk. Mulberry silk is superior in qualitybecause it is soft, lustrous and creamy white in colour. It is secreted by thesilk producing glands of silk worm.
• The process of raking out threads from the cocoon is called Reeling.
• It is believed that silk was first discovered in China by the Empress Si LingChi
• Kancheepuram, Siruvanihadu, Thirubhuvanam are famous for silk in Tamil Nadu.
• Honey bees live in bee hive
• There are three kinds of bee hive.The work of the queen bee is to lay eggs .There are few hundreds of male bees which help in reproduction .The worker bees are thousands in number.They perform various functions
• Some Indian varities of bees are
• Composition of Honey.

1. Sugar – 75%
2. Water – 17%
3. Minerals – 8%

• The rearing of honey bees to produce honey in large scale is known asapiculture.
• The rearing of hens and other lowls to produce eggs and fesh is called Poultry farming.
• The place where the fowls are reared is called Poultry farm.
• Namakkal district in Tamil nadu is famous for poultry industry
• Hens that hatch eggs are called Broody hens.
• The eggs hatch after 21 days.
• Expand TAPCO – Tamil Nadu Poultry Development Corporation.

Silver Revolution

• The massive step taken in India to increase egg production by adoptingenlightened practices of poultry is called silver Revolution
• Some of the famous wildlife sanctuaries in Tamil Nadu are are Vedanthangal,Mudumalai, Mundanthurai, Kalakadu and Kodiakarai

Care of Wild Life

• Wildlife protection and maintenance is called wildlife conservation.
• Some of the conservation measures areas
• Setting up of National Parks and wildlife Santuaries
• Stringent action against poaching.
• discouraging deforestation
• Blue Cross is a registered animal welfare society

Siddha system of medicine

Tamil maruthuvam)

• The word Siddhar is derived from “Siddhi” which means”Eternal Bliss”.
• Agastiyar, being the first Siddhar, is called the Father of Siddha medicine.
• Some of the medicines used in Siddha are Chooranam ,Mathirai,Thailam,Legiyam,Rasayanam,Paspam,Chandooram

Ayurveda

• Auyrveda means Science of Life (Ayur =Life, Veda = Science).
• The most amazing part of Ayurveda is that it uses almost all methods of healing like Yoga,Meditation,Purification  and so on.

Homeopathy Medicine

• Homeopathy is a form of alternative medicine, first proposed by Germanphysician Samuel Hahnemann in 1796.

Unani Medicine

• Unani Medicine is a form of traditional medicine based on the teachings ofGreek physician Hippocrates, and Roman physician Galen, and developedin to an elaborate medical System by Arab and Persian physicians

Diabetes mellitus

• The food that we eat is broken down into glucose.
• When the blood glucose level exceeds the normal limit (80 – 120 mg/ dl) theperson is affected by Diabetes t
• The process of keeping the food for long time without spoilage is called preservation of food.

Purpose of Preservation

• To prevent the loss of food from spoilage.
• To retain the colour, taste and nutritive value of the food
• To make the food available throughout the year
• To add variety to our meal.

Methods of Preservation

• Preservation involves the prevention of growth of bacteria, fungi and other microorganisms in the food.Even action of the enzymes within the food should be prevented

Drying

• This method involves the removal of water from the food by drying.

Heating

• Heating is a method of food preservation. It kills the microorganisms anddenature the enzymes present in the food. Hence food is stored safely. eg.Boiling milk before it is stored or used. ‘
• This method was discovered by Louis Pasteur

Crop Production and Management

Agriculture:

• Science that deals with the growth of plants and animals forhuman use is called agriculture.
• Current Population of Indian in 2010 is around 1,192,196,919 (1.19 billion) people
• Indian population had grown by 21.34% between 1991 and 2001. It isexpected to exceed by 20% more in 2050

Preparation of Soil and Sowing

• Ploughing or tilling
• .Levelling and
• Manuring

Irrigation

• Plants need water for germination, drawing nutrients and preparing their food by photosynthesis.

Trational Method

• In our country traditional systems of irrigation like,
• Pulley system (moat)
• Chain pump and
• Level system (rahat)

Modern Methods

More to know

• The Kara kum canal in Turkmanisthan is the longest irrigation canal in theworld. It is over 1300 km long.
• PAP – Parambikulam Aliyar Project ranks first in India in the top 10 list ofthe World for its massive storage capacity
• Indira Gandhi canal –It is one of the biggest canal project in India .Starts from Harike Barrage at Sultanpore
• State warehousing corporations provide storage facilities for agriculturalproduct, fertilizers, etc.
• Thanjavuris said to be Rice bowl of Tamilnadu

Agmark:

Agmark grading and standardization is central sector scheme tocheck the quality and standard for agricultural products. The grades givenare Grade 1, 2, 3, 4 or Special, Good, Fair and Ordinary.

Crop Rotation

                  The practice of growing a cereal crop and the pulse crop alternately in thesame field in successive season is called as crop rotation.

Biotechnology in Agriculture

• Biotechnology is the field of applied biology that involves the use of livingorganisms and bio-processes in engineering, technology, medicine andother field requiring bioproducts.
• Biotechnology has also revolutionized research activities in the area of agriculture.
• There are seven different techniques that are used in plant improvement.
• Selection
• Hybridisation
• Polyploidy breeding
• Mutation breeding
• Protoplast fusion
• Tissue culture and
• Genetic engineering