3. The mixture various gases like o2,co2,watervap- Our,nitrogen, etc is called air. It comprises of atmosphere- The multilayered gaseous envelope surrounding The planet earth is called atmosphere.

4. Air :Air is a mixture of different gases. Atmosphere : The blanket of air which covers the earth. 78 % 1% 21%

5. Atmosphere controls the temperature of planet. It generally makes the temperature constant. Different layers of atmosphere- 1. Troposphere-10-20km 2. Stratosphere-20-50km 3. Mesosphere-50-100km 4. Ionosphere-100-200km 5. Exosphere –200-50km

6. Presence of various toxic gases in the atmosphere like carbon dioxide, carbon, mono oxiode, xides of sulphur, nitrogen, fluoride, lead,nickel,arsenic,cadmium, etc causes Air Pollution.

7. SOURCES OF AIR POLLUTION- 1. Heavy metals. 2. Photochemical smog. 3. Smokes. 4. Ionising radiation. 5. Automobile exhaust. 6. Biocides elements. 7. Radioactive elements. 8 Industrial waste

8. Water- The most unusual natural compound found on earth and which fulfills almost various demands of different living things. About three fourth of the earth surface that is 75 are covered with water. Now day’s water is also being polluted by human beings.

9. When water becomes unfit for drinking and other use then water is said to be polluted. CAUSES OF WATER PLLLUTION 1. Dumping of wastes from the industries into the water bodies. 2. Washing near water bodies. 3. Spraying chemical in water field. 4.conducting various radioactive tests in water. 5.dumping of cabbages and household wastes in to the water bodies.

10. SOURES OF WATER- 1.River. 2.Pond. 3.spring. 4.well 5.rainwases

11. Soil is the portion of the earth surface consisting of disintegrated rock and decaying organic material. It provides the support for many plants and animals

12. HOW SOIL IS FORMED? Soil is formed from the rock by under going the following two process- 1.Weathering 2.Paedogenesis Over long periods of time, thousand and millions of year, the rock at or near the surface of the earth are broken down by various physical, chemical and some biological process. The end product of this Breaking down in the fine particle of soil Composition of soil- 1.Gravel. 2.Sand particle. 3.Clay particle.

13. DIFFERENT TYPES OF SOIL 1.Sandy soil. 2.Clayey soil. 3.Lomy soil. 4.Residual soil. 5.Black soil. 6.Red soil. 7.Laterite soil. 8.Transported soil. 9.Alluvial soil. 10.Desert soil. 11.Mountainous soil. SOIL EROSION- The process of removal of superficial fertile top layer of soil by various agencies or forces is called soil erosion

14. FORMATION OF RAIN- Rain is formed by evaporation and condensation Of water through water cycle in which distribution of water takes place. Rain is a very important things because it carries out all the agriculture processes in the plants.

15. FORMATION OF RAIN- Rain is formed by evaporation and condensation Of water through water cycle in which distribution of water takes place. Rain is a very important things because it carries out all the agriculture processes in the plants. So, we should conserve rain by contracting dams, pools etc.

16. Water is a compound and includes two vital elements hydrogen and oxygen. It forms a very Important components of the environment and survival of all living organism depends on it. Ocean is the biggest store house of water which on evaporation from clouds and which after condensation down as rain or snow. After rain it passes through puddles, ponds and rivers and get collect again in the ocean.

17. The circulation of water in this manner is known as HYDROLIC CYCLE or WATER CYCLE. This cycle is driven By solar power and also per performed through living organisms such as absorption and transpiration of water by plants and drinking by Animal. The formation of soil, too, depends on water.

18. Nitrogen is another important chemical on earth and present in all the living organism in the form of protein, amino acids and nucleic acids. Further process going on in this cycle they are- First nitrogen has to be converted into nitrates for the use of plants. This can be done either by industrial nitrogen fixation like by some nitrogen fixation bacteria such as azotobactor which convert the atmospheric nitrogen into nitrates which are soluble in water this process is called nitrogen fixation.

19. After an animal excretes urea or uric acid or after an animal Or plants dies, certain bacteria carry out ammonification : they produce ammonia ions, or still other bacteria can change it to nitrate[NO3-] by nitrification. Plants take in some of the nitrates produced in this way. The process of ammonia formation is called ammonification. Some microorganisms (nitrosomonas converted ammonia into nitrates) This process is called nitrification. Finally there are some (decomposer, e.g.…, pseudomonas) Which reduce nitrates back to nitrogen or to ammonia or to some other oxides. This process is called denitrification. Free nitrogen returns to atmospheric pool and oxides are taken up by plants.

20. The carbon is an important constituent of organic compounds found in all living things beings in the form of carbohydrates, fats, proteins, and nuclei acids. Like the water cycle is linked to energy flow because producers – Including photosynthetic plants of forests and oceans and chemo synthetic bacteria of deep-sea vents- require environmental energy (either sunlight or inorganic hydrogen compounds) to trap carbon into sugars (proteins and fats). The trapped carbon comes from carbon dioxide in surrounding air or water.

21. As the cycle proceeds, consumers devour the organic carbon compounds that producers manufacture. Then, via respiration, both consumers and producers return carbon to the nonliving environment in the form of carbon dioxide. Some carbon accumulates for many years in wood and is eventually returned to the atmosphere in fires or through consumption and respiration by fungi, bacteria and other detritibvores. Volcanic eruption also releases carbon dioxide to the atmosphere. Thus, there is complete cycling of carbon in the environment by various living and nonliving beings.

22. Oxygen is one of the constituents of water and form about 21% of the air in the atmosphere. It is required for respiration for all living organisms. Oxygen cycle runs through the following process- By burning the materials to produce oxygen combining with nitrogen to produce oxides of nitrogen, proteins, etc. These compounds after breaking down releases oxygen in the atmosphere and maintain forever in the environment. These way oxygen cycle works

23. Increase in temperature of earth due to increase in concentration of some gases like co2, methane, water vapour, dust particles which causes melting of the glaciers or ice on the mountains which increase water level of water bodies, this increase in water level causes, submerging

24. The oxygen in the atmosphere is the source of ozone co3. The ozone layer protects organisms By preventing most of the ultraviolet and X-ray from reaching the earth’s surface, otherwise it causes different disease like skin cancer, cataract and other skin problems.. Today, a global problem revolving our head that is the hole in the ozone layer. This hole is in over the Antarctica and this has passed the threat of damages to inhabitants of earth from short-wave ultraviolet rays.

25. Life on the depends on resources like soil, water, and air, and energy from the sun. Uneven heating of air over land and water bodies causes winds. Evaporation of water from water bodies and subsequent condensation give us rain. Rainfall patterns depend on the prevailing wind patterns in an area. Various nutrients are used again and again in a cyclic fashion. This leads to a certain balance between the various components of the biosphere. We need to conserve our natural resources and use them in a sustainable manner. Pollution of air, water, and soil affect the quality of life and harm the biodiversity.

26. Life on earth depend on resources like soil, water and air and energy from the sun. Uneven heating of air over land and water bodies causes winds. Evaporation of water from water bodies and subsequent condensation give us rain. Rain fall pattern depend on the prevailing wind pattern in an area. Various nutrients are used again and again in a cyclic fashion. This leads to a certain balance between the various components of the biosphere. Pollution of air, water and soil affect the quality of life and harm the biodiversity. We need to conserve our natural resources and use them in a sustainable manner.

27. THERE ARE THIRTEEN NUTRIENTS ESSENTIAL FOR CROPS OF THESE SIX ARE REQUIRED IN LARGE QUANTITES AND ARE KNOWN AS MACRO NUTRIENTS WHEREIS SEVEN NUTRIENTS ARE REQUIRED IN SMALL QUANTITIES AND ARE KNOWN AS MICRO NUTRIENTS MANURE AND FERTILIZERS ARE THE MAIN SOURCES OF NUTRIENT SUPPLY TO CROPS. MIXED FARMING IS A SYSTEM OF FARMING ON A PARTICULAR FARM WHICH INCLUDES CROP PRODUCTION, RAISING OF LIVES STOCK ETC… MIXED CROPPING IS GROWING OF TWO OR MORE CROPS SIMULTANEOUSLY ON THE SAME PIECE OF LAND THE GROWING OF DIFFERENT CROPS ON A PIECE OF LAND IN PRE-PLANNED SUCCESSION IS CALLED CROP ROTATION. GROWING TWO OR MORE CROPS IN DEFINITE ROW PATTERN IS KNOWN AS INTER – CROPPING….

28. The condition including all the substances, forces and organisms under which an organisms lives is called its Environment. All living organisms including plants, animals and micro organisms form Biotic component. It consists of geographical conditions such as the temperature, rain fall, soil, seasons and the climate.