VIII NATURAL RESOURCES:-LAND, SOIL AND WATER

CH-2 NATURAL RESOURCES:-LAND, SOIL AND WATER

Earth is a unique planet in the Solar system, because Life is possible on the earth.

Earth surface is divided in to two parts-

1.Land cover about 29%

2.Water about 71%

LAND RESOURCES

Land is most important natural resources because it used for growing of crops, building house, construction of road and railway tracks establishing industries, grazing of animals, mining etc.

Soil- Lithosphere consists of loose surface material called soil.

Humus-The organic component which consists of dead and decomposed part of animals and plant is known as humus.

LAND USE PATTERN

Land is used for various purposes such as for cultivation of crops, building of houses, road, railways, grazing of animals it is commonly known as land use pattern.

The percentage of land used for various purposes varies from one region to another.

Utilisation of land is determined by the continuous interplay of the physical factors like relief, soil, climate condition, mineral resources etc. and the human factors like density of population and the technological and social requirement of the people.

SOIL RESOURCES

1.Soil is of immense value of the farmers.

2.Agricultural production is mainly dependent upon the fertility of soil.

3.Animals also depend upon the soil to satisfy their needs.

SOIL EROSION

The top layer of the soil is removed by natural agencies, like water, wind, glacier, etc.

CAUSES OF SOIL EROSION

1.Deforestation :- It is the first and main cause of soil erosion that is not even in control.

2.Poor soil structure:-If the soil is sandy then soil erodes easily even by wind.

3.Human Activities:-Activities like overgrazing poor agricultural methods etc. are causing soil erosion.

FACTORS RESPONSIBLE FOR THE FORMATION OF SOIL

1 The Parent rock:- The original rock from soil is formed by the process of weathering is known as the parent rock. Ex-The soil of India is derived from the lava rock.

2.The vegetation cover:-Plant grows in the cracks existing in the rocks with time, root of the plant start penetrating in the cracks and make it wider. As soon result it disintegrates it into smaller pieces and helps in the soil formation.

3.Time:-Time gives maturity to the soil. Soil is a renewable resources but it takes thousands of years to develop a very thin layer of it on the earths surface. Ex-Nile delta and Delta formed by Ganga -Brahmputra rivers have very deep and fertile soil.

4.The topography:-The location of soil on landscape can affect now the climate processes affect it. Ex-The northern plains of India has thick soil cover than Himalayas. Even within mountains, river valleys have thick soil cover.

5.The climate:-Climate factors like temperature and rainfall affect the soil formation ex-In the area of high rainfall and extreme temperature, rocks are easily weathered which affect the soil formation.

SOIL CONSERVATION

It means methods by which soil is prevented from being eroded.

METHODS FOR SOIL CONSERVATION

1.Afforestation-It is the process of planting more trees and seeds on land. It reduces the surface runoff and bind the soil.

2.Rows of trees or shelter belts are planted in desert regions to protect the fields from wind erosion.

3.Overgrazing by animals like sheep and goals must be checked.

4.Steps should be taken to check reckless cutting cutting of trees.

5.Flood should be avoided by building dams across the rivers.

WATER RESOURCES

Water is one of the most important resource. Earth is also called watery planet because nearly 70℅ of the earth surface is covered with water.

1.Oceans and seas 97℅

2.Fresh water 3℅

Fresh water

1.lakes, rivers, atmosphere and soil moisture etc. ---0. 32℅

2.Ice caps and glaciers ----2. 0%

3.Ground water--- 0.68

HYDROLOGICAL CYCLE

The main source of fresh water is rainfall. The rain water continuously get recycled in nature through evaporation, condensation and precipitation, which is known as hydrological cycle.

POLLUTION OF WATER

Sewage garbage and liquid waste of house hold agricultural lands and factories are discharged into lakes and rivers. These wastes contain harmful chemicals and toxins which make the water poisonous for aquatic animals and plants.

MULTIPURPOSE RIVER VALLEY PROJECTS

It have been developed all over the world to utilize water.

Damoder River Valley Project

Hirakund Dam in India, it is multipurpose River Valley project.

Objectives of Multipurpose River Valley Projects-

Main objective of Multipurpose River valley project to storing water.

This stored water is used for several Purposes, such as providing irrigation generating hydroelectricity, afforestation, control floods, navigation etc.

ECOLOGICAL PROBLEM CAUSED BY BUILDING LARGE DAMS

1.Extensive forests submerged under water.

2.River water gets diverted.

3.population get displaced.

4.Aquatic life get affected.

5.Flow of under ground water is also checked.

METHODS FOR THE CONSERVATION OF WATER

1.Water harvesting is one of the methods of saving surface runoff.

2.The rain water can be impounded by making dams across the rivers.

3.The demand of water for industries can be met by the recycled water.

4.Maintenance of lakes and ponds also helps in increasing the aquifer of underground water.

5.Water can be conserved by educating and sensitizing people towards the urgent need to conserve water so that they donot waste fresh water.

CH-NATURAL RESOURCES:-LAND SOIL AND WATER

SHORT QUESTION WITH ANSWER

Question 1.

Why is soil considered an important resources?

Answer:-

1.Soil is of immense value of the farmers.

2.Agricultural production is mainly dependent upon the fertility of soil.

3.Animals also depend upon the soil to satisfy their needs

Question 2

.Highlight any three causes of soil erosion.

Answer:-1.Deforestation :- It is the first and main cause of soil erosion that is not even in control.

2.Poor soil structure:-If the soil is sandy then soil erodes easily even by wind.

3.Human Activities:-Activities like overgrazing poor agricultural methods etc. are causing soil erosion.

Question 3.

Explain hydrological cycle with the help of a diagram.

Answer:-

The main source of fresh water is rainfall. The rain water continuously get recycled in nature through evaporation, condensation and precipitation, which is known as hydrological cycle.

Question 4.

How does River water get polluted? Explan.

Answer :-
Sewage garbage and liquid waste of house hold agricultural lands and factories are discharged into lakes and rivers. These wastes contain harmful chemicals and toxins which make the water poisonous for aquatic animals and plants.

Question 5.Identify any three ecological problem caused by building large dams.

Answer:-

1.Extensive forests submerged under water.
2.River water gets diverted.
3.population get displaced.
4.Aquatic life get affected.
5.Flow of under ground water is also checked.

LONG QUESTION WITH ANSWER

1.Explain any five factors responsible for the formation of soil.

Answer:-

1.The Parent rock:- The original rock from soil is formed by the process of weathering is known as the parent rock. Ex-The soil of India is derived from the lava rock.

2.The vegetation cover:-Plant grows in the cracks existing in the rocks with time, root of the plant start penetrating in the cracks and make it wider. As soon result it disintegrates it into smaller pieces and helps in the soil formation.

3.Time:-Time gives maturity to the soil. Soil is a renewable resources but it takes thousands of years to develop a very thin layer of it on the earths surface. Ex-Nile delta and Delta formed by Ganga -Brahmputra rivers have very deep and fertile soil.

4.The topography:-The location of soil on landscape can affect now the climate processes affect it. Ex-The northern plains of India has thick soil cover than Himalayas. Even within mountains, river valleys have thick soil cover.

5.The climate:-Climate factors like temperature and rainfall affect the soil formation ex-In the area of high rainfall and extreme temperature, rocks are easily weathered which affect the soil formation.

2.What is meant by land use pattern? Why is it important to study the land use pattern? List the factors influencing the utilisation of land.

Answer:-

LAND USE PATTERN

Land is used for various purposes such as for cultivation of crops, building of houses, road, railways, grazing of animals it is commonly known as land use pattern.

The percentage of land used for various purposes varies from one region to another.

Utilisation of land is determined by the continuous interplay of the physical factors like relief, soil, climate condition, mineral resources etc. and the human factors like density of population and the technological and social requirement of the people.

3.What are Multipurpose River valley projects? Name any two such projects. List the main objectives of a multipurpose river valley project.

Answer:-

MULTIPURPOSE RIVER VALLEY PROJECTS

It have been developed all over the world to utilize water.

Damoder River Valley Project
Hirakund Dam in India, it is multipurpose River Valley project.

Objectives of Multipurpose River Valley Projects-

Main objective of Multipurpose River valley project to storing water.
This stored water is used for several Purposes, such as providing irrigation generating hydroelectricity, afforestation, control floods, navigation etc.

Question 4.Suggest any five steps to conserve soil.

Answer:-

SOIL CONSERVATION

It means methods by which soil is prevented from being eroded.

METHODS FOR SOIL CONSERVATION

1.Afforestation-It is the process of planting more trees and seeds on land. It reduces the surface runoff and bind the soil.

2.Rows of trees or shelter belts are planted in desert regions to protect the fields from wind erosion.

3.Overgrazing by animals like sheep and goals must be checked.

4.Steps should be taken to check reckless cutting cutting of trees.

5.Flood should be avoided by building dams across the rivers.

Question 5
Suggest any five methods for conservation of water.

Answer:-

METHODS FOR THE CONSERVATION OF WATER

1.Water harvesting is one of the methods of saving surface runoff.

2.The rain water can be impounded by making dams across the rivers.

3.The demand of water for industries can be met by the recycled water.

4.Maintenance of lakes and ponds also helps in increasing the aquifer of underground water.

5.Water can be conserved by educating and sensitizing people towards the urgent need to conserve water so that they do not waste fresh water.