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Plains are known for agriculture and dense population. Plains, 43% area of India, fulfill man’s many needs. The agriculture depends upon plain.

The land which is not used for agriculture for 1 to 5 years is left vacant. It restores the fertility of the soil. It is called fallow land.

Soil forms the uppermost part of the earth's surface called “crust”. The formation of soil is a very complex and time-consuming process that involves a number of factors. Basically, the breakdown of rocks with time leads to the formation of soil, and this process is called the “Weathering” of rocks. For this breaking down of rocks, a number of factors are needed like, 

● Sun: - During daytime sun heats up the rocks due to which a little bit of expansion of rocks occurs. At night when the temperature falls rocks tend to contract, due to this simultaneous and subsequent heating, and cooling cracks are formed inside the rocks. This phenomenon can be easily observed in hilly areas during the rainy season. After the rain when the sun emerges it heats up the wet and cool mountains but they tend to resist due to which breaking of mountains occurs. 

● Water: - Water is another factor that helps in soil formation. Water fills up the cracks developed due to the heating and cooling of rocks and at causes the cracks to widen up more. Also, water takes away the smaller rocks and causes them to grind over one another ultimately causing them to break. 

● Wind: - wind also works the same way by taking away the sand from one place to another. 

● Living organism: - Some living organisms like lichens are the pioneer community i.e. they colonize the rocks first as the first living organism and they secrete certain acids when they grow on these rocks. Due to this secretion rocks becomes weak and break down easily. Roots of bigger trees can penetrate these rocks and can help in their breakdown. Along with them, other microorganisms and mosses help in the weathering of rocks.

Soil erosion is the removal of the topmost fertile layer of the soil. Due to factors like floods, heavy blowing winds the topmost fertile layer is removed and the land left becomes barren. 

In order to prevent this, 

1) Plant more and more trees. Roots of trees tend to bind the soil along with them and doesn’t allow its runoff. 

2) Growth of grasses, herbs, shrubs, and smaller plants like bryophytes helps in the prevention of soil erosion since their roots are present only in the upper layer. 

3) At hilly areas, for farming step farming should be done so that even if water erodes soil from the top step, it gets trapped at the subsequently created steps.

Less than 0.01% of the water on the earth is surface water, but if used judiciously, shall last for a long time.

Drip irrigation can reduce water consumption by 70%.

Soil Erosion 

Carrying away of upper fertile layer of soil by rain, wind, human activities and wrong agricultural practice is called soil erosion. 

Causes 

• Over grazing of land. 

• Removal of top soil by wind and water. 

• Due to lack of trees the upper layer of soil is eroded by air and water. 

• Leaving land uncultivated for long time. 

1. Fuel is a substance that is used in day-to-day life and burned to generate energy. 

2. Fuels such as coal, wood, oil, gas provide energy when burned. 

3. Fuels are found in solid, liquid or gaseous state.

1. Soil erosion is caused by poor farming methods such as repeatedly planting the same type of crop in the same place. 

2. These methods deplete nutrients in the soil. 

3. Soil erosion Is also caused by water and wind currents. 

4. When farmers plough up and down hills, soil erosion occurs. 

5. Overgrazing by cattle also causes soil erosion. 

6. Natural floods causes the extensive damage to the top layer of the soil.

Contour strip cropping helps in reducing soil erosion.

Biodiversity: The variety of living things that populate the earth.

1. Biodiversity is the variety of living things that populate the earth. 

2. The products and benefits we get from nature rely on biodiversity. 

3. We need to protect biodiversity to ensure plentiful and varied food sources. 

4. Biodiversity is important for more than just food. For instance we use between 50,000 to 70,000 plant species for medicines world wide.

Hydrogen, biofuels, methanol or wood alcohol, ethanol or green alcohol are some of the alternative fuels.

Petrol, diesel, Kerosene, lubricating oils and naptha represent various forms of petroleum products.

i. The process shown is formation of mineral oil and natural gas.

ii. 1. Mineral oil is the liquid fuel formed by the decomposition of organic substances buried underground. 

2. Millions of years ago, bodies of dead sea organisms sank to the bottom of the sea. 

3. Layers of soil and sand collected on them. 

4. Due to high pressure and temperature the remains of the dead organisms were transformed into mineral oil. 

5. The underground mineral oil is extracted through oil wells.

iii. Natural gas is also formed along with mineral oil. It contains methane, ethane, propane and butane gases.

iv. When mineral oil is refined by fractional distillation products produced are petrol, diesel, kerosene, naphtha lubricating oil, tar, etc.

The people of Rajasthan who saved forests are Bishnois

Characteristics of CNG:

1. Catches fire easily. 

2. No solid waste remains after combustion. 

3. Carbon dioxide and water are formed in small quantities. 

4. Other pollutants are not produced. 

5. Can be transported easily. 

6. Combustion can be controlled easily.

The types of coal are 

1. Anthracite – Carbon content is about 80%, it is very hard. 

2. Lignite – Carbon content is about 60%-65%. 

3. Bituminous Coal – Carbon content is less than 40%.

D) Deforestation accqunts for 20% of the world’s green house gas emissions.

Peat, lignite (brown coal), bituminous coal and anthracite are various types of coal. 

Anthracite is the coal of the highest grade.

i. Bauxite

ii. Anthracite

iii. extraction, purification

iv. ONGC

v. LNG and CNG

vi. Methane

vii. Sandalwood and oil of Encalyptus

viii. Adulsa

B) a is true, b is false

D) Bread Mould

C) Wood, wind, sun

D) All of the above

An extensive area of land covered by a variety of plants is called a forest. A forest is a natural habitat of plants, animals and microbes.

D) Both statements I and III are correct

C) carbon monoxide

Yes, there are very large reserves of tin chromium, phosphates, copper, zinc, iron, lead, manganese, sulphur, uranium etc. in the ocean and seabed.

Coal is used a fuel in thermal power plant for the production of electricity. Coal products are used in the making of plastics, drugs, cosmetics, fertilizers, medicines, nylon etc.

1. A forest is a natural habitat of plants, animals and microbes. 

2. Forest help improve and maintain the quality of environment. 

3. Forest helps in prevention of soil-erosion, help to control floods, protects wild life, maintains the balance of atmospheric gases. 

4. We get many medicinal plants from forest which help in treatment of various diseases. 

5. Examples Adulsa, Bel, Neem, periwinkle, amla tulsi, cinnamon. 

6. We also get wood, firewood from trees like teak, mahogani, neem, sababhul. Wood is useful for making furniture, farming implements, in construction work. 

7. Forest wealth includes fibres, paper, rubber, gum and aromatic substances. 

8. We get fragrant essential oils from lemon grass, vanilla, kewada and eucalyptus. 

9. They are used for making soaps, cosmetics and incense sticks. We get various fruits, bulbs, roots, honey, sealing wax, catechu dyes etc. from forest.

Forest uses: Forests are also one of the natural resources. They provide fruits, flowers, medical plants, wood, etc, Forests are the shelters for tribals. Forests prevent soil erosion. The trees here give out oxygen and increase its quantity in the atmosphere. Such useful and the most valuable forests are being destroyed by various human activities like urbanization, industrialization, construction of dams, etc. We must not forget that deforestation means destroying life on earth.

All the pictures given above show large scale emission of smoke through different agencies. 

This smoke directly mixes with the atmosphere, disturbing the balance between the constituents of air and causing air pollution.

Answer is (A) Coal

Answer is (D) Recycle

C) Using cellphones

Answer is (D) Reuse

Answer is (C) Coal

By practising four R’s-reduce, reuse, recycle and recover the things, preparation of recharging structures for water, protecting the wild life and habitats we can manage the resources.

Along with international, national or state organisations there is private organisation named International Union for the Conservation of Nature founded by private groups.

It means to prevent the soil erosion and to maintain its quality. It is directly connected to retain the soil particles at their original place.

Erosion means the transportation of land particles from one place to another with the help of moving air and water. If the soil particles are carried away because of heavy rain or by stormy wind, the agricultural production decreases. It is extremely necessary to maintain this upper layer for agriculture. So the soil erosion should be prevented.

It is seen in the area where the climate is arid or semi-arid. This soil is sandy and fertile which contains more minerals.

It is the layer or the surface of the matter formed due to- the mixture of the scattered material of the parental rocks and vegetation.

It develops in humid region due to accumulation of biotic elements. Biotic elements and minerals are excess in such soil, but it shows insufficiency in phosphate and potash.

The two ways by which water harvesting can be undertaken are 

1. Capturing run off water from, rooftops. 

2. Capturing run off water from local catchments.

The practice or removing individual plants or small groups of plants leaving other plants standing to anchor the soil is called selective harvesting.

C) ground water

C) Contour strip farming

Correct option is B) i, ii, iii

Conservation of water resources :
It includes all the policies, strategies and activities made to manage the natural resource water, to protect the water environment and to meet the current and future human demand. Some of them are as follows—

1. Use of water strictly according to the need.
2. Covering of bodies like wells.
3. Avoiding pollution of water.
4. Repairing of leaky taps to save water.
5. Prohibition of atomic test in the oceans.
6. Less industrialization in the coastal regions.
7. Spraying of hexadecanol or cetyl alcohol over the desert or reservoirs to prevent evaporation. It form thin layer that retard evaporation.
8. Limited use of underground water which is constantly getting less.
9. Use of fountain irrigation and drip irrigation techniques to reduce water loss caused in surface irrigation.

Management of rain water :
It is also called as rain water harvesting. It can be
achieved as follows:

1. Accumulation of rainwater for reuse on site.
2. Collection of rainwater in well or shafts or borehole or pits.
3. Formation of small dams to collect rainwater in mountains.
4. Prevention of soil deposition in natural water bodies like lakes, ponds, ditches etc.
5. Improvement of irrigation system in desert and mountain regions with the help of canals. Such as Indira Gandhi Canal Project.