Geography Ch-2
Land , soil ,water natural vegetation & wild life
 

Activity – 1 draws & prepare model of soil profile.

Land

Land use

 

Land is used for different purposes is termed as land use  Such as agriculture , mining , building , houses etc.

Factors affecting the land use

 

Physical factors & human factors

Physical factor include soil climate minerals topography water rainfall temperature etc

Human factor includes population density & technology etc.

 

Importance of land

 

Land is very important for us because We live on it.

We fulfill our basic need from land. We use land for agriculture, industries, human settlement and transportation.

 

Land degradation 

Land degradation Is a process in which the biophysical value of land  and its fertility degrades .

Reasons for land degradation are soil erosion deforestation, ,desertification ,, over grazing excessive mining activities

Well planned use of land is called

land conservation

 

Well planned use of land is called land conservation

land conservation common methods of land conservation are afforestation, lend reclamation , regulated use of fertilizers and control on over grazing  .

Soil

*Soil is the top most layer of the earth .It is made up of organic and inorganic matter *The right mix of organic and inorganic matter make soil fertile

*Soil = organic matter + inorganic matter

*Humus  it is formed by  decaying remains of plants and animals it adds fertility to the soil 

 

Importance of soil

*It is one of the most important renewable natural resource

*It determines agricultural productivity of an area.

 *Soil determines the natural vegetation and type of crop production of an area.

 *It also influences the land use of an area.

 *Areas of fertile soil are agriculturally productive and densely populated.

 

Weathering

*The breaking  up and decay of exposed rocks, by temperature changes, frost action, plants, animals and man.

 

Soil forming factors

*The major factors of soil formation are the nature of the parent rock and climatic factors.

*Other factors are the topography, role of organic material and time taken for the composition of soil formation.

1. Parent Rock - Determines colour, texture, chemical properties mineral, content, permeability.

2. Relief -Altitude and slope, determine accumulation of soil.

3. Flora, Fauna and Micro-organism - Affect the rate of humus formation

4. Time - Determines thickness of soil profile

5. Climate Temperature, Rainfall influence  rate of weathering and humus

 

Types of soil

(1) Alluvial Soil                                    (2) Black Soil

 (3)  Red and Yellow Soil                             (4)  Laterite Soil

(5)  Mountain Soil                                         (6)  Desert Soil

 

Show the major soils on a Indian political map.

 

 

Soil Profile

top soil (A – Horizon

sub soil (B – Horizon

weathered rock(C – Horizon)

Bed rock  (parent rock )

**Draw and explain the soil profile .

 

Problems associated with soil
*Soil erosion and depletion are the major threats to soil  as a resource.

*Both human and natural factors can lead to degradation of soils.

*Factors which lead to soil degradation are deforestation, overgrazing, overuse of  chemical fertilizers or pesticides, rain wash, landslides  and floods.

                   

Soil erosion

*Removal of  top layer of the soil by natural and human factor is called soil erosion.

*Human activities as well as natural forces cause the removal of the top soil.

Causes

*Human factors leading to soil erosion are :

a Deforestation :-Due to heavy deforestation, soil erosion is increasing.

b Overgrazing :-In many regions people still practice grazing of cattle, goats and sheep. Gradually this leads to soil erosion.

c- Construction

d Mining

e Soil erosion is also caused due to defective methods of farming.

*Natural forces like wind, glacier and water lead to soil erosion.

Soil conservation methods

In hilly and mountainous areas the following measures can control soil erosion

 and help in soil conservation.

Contour ploughing or ploughing along the contour lines of a highland

can reduce the flow of water down the slopes.

Terrace cultivation or cutting of steps around the slopes for agriculture also

checks downhill flow of water and controls soil erosion.

* western and central Himalayas have well developed terrace farming.

Afforestation or planting of trees in the hilly regions can help in soil conservation.

Growing thorny bushes in arid and semi arid regions can help in binding

 the soil with the roots and also reduce the speed of wind.

Strip cropping: Large fields can be divided into strips.

Strips of grass are left to grow between the crops.

 This breaks up the force of the wind reducing its effect.

Shelter belt

Planting lines of trees to  break up of the force of the wind  are called shelter belts .

 

* Mulching ,Proper management of waste lands, control of mining activities proper discharge and disposal industrial effluents wastes after treatment can reduce land  soil and water degradation in industrial and sub urban areas.

 

Water

* Water is a renewable resource.

*Water covers nearly 3/4th of the Earth’s surface.

*  96.5% of the total water on  Earth is in oceans.

*  2.5% is freshwater that exists in rivers and glaciers.

* Fresh water is mainly obtained from surface-runoff and ground water.

 

Importance of water

*Water is a scarce resource as only 1 % of all the water available is fresh water

which we can use.

*Water is vital for human survival.

*Water is required for domestic needs and for economic activities like industries and agriculture.

*It is believed that life originated in water.

*Water is used for transportation.

*Water is used to generate hydroelectricity

*It is a basic input for agriculture . cultivation growth of crops depend on availability of water .

*Water is an important component of ecosystem.               

Water pollution

*It means spreading of harmful substances into water

*Major causes of water pollution are

*Disposal of industrial waste. increasing urbanization and industrialization .

*Overuse of Chemical fertilizes and pesticides.

*Over exploitation and contamination of water sources

                   

Conservation of water  resources

 

The valuable water resource can therefore be conserved  by adopting  following  means of conservation

 

1.Forest and vegetation cover slow the  surface runoff and replenish underground  water.

2. Water harvesting is another method to save surface runoff. Water is used for irrigating fields.

3.The canals should be  properly lined to minimise losses by water  seepage.

4. Sprinklers effectively irrigate the  area by checking water losses through  seepage andevaporation.

5.In dry regions  with high rates of evaporation, drip or  trickle irrigation is very useful.

6. Polluted water should be treated   before releasing it in water bodies.

7. Building dams on river is an most effective way of water conservation these multipurpose projects not only control floods.                                                           

Wild life and natural vegetation

 

Biosphere

*Biosphere is the sphere of life.

*It is the narrow zone of the earth where land water and air interact with

 each other to support life.

*Natural vegetation and wild life exist only in biosphere.

 

 Ecosystem

*In the biosphere living beings are interdependent on each other.

*They together form life supporting system is known as ecosystem

Types-

Natural **

Manmade ecosystem**

 

Importance of forest

*The raw materials for paper industry, match making, gums and resins are also extracted from the forest products.

*They help in enhancing the quantity of rainfall.

*Forest provides us timber. They are natural habitat of wild animals

*Forests produce oxygen we breathe protects soil

*They acts as the shelter belts essential for growing crops

*Forests help in storage of underground water

*Plants give us fruits nuts gum medicines oils paper etc.

*They help in controlling soil erosion. Forest and vegetation cover slow the

 surface runoff .

*Tribals directly depend on them for their food ,drink, medicine, culture.

*They play key role in the ecological system as they are the primary producers on which all other living being depend.

*They provide certain types of herbs which are in turn used to produce useful medicines.                                                                

 

Causes of the forest depletion

 

Deforestation,

Soil erosion

Forest fires

Natural calamities like  Drought ,tsunami and landslides.

 

Mining

Urbanization and Industrialization

Dams

Overgrazing

Jhum Cultivation

Pollution

Constructional activities

 

are  the major  human  and natural factors responsible for the rapid depletion of these  forest resources .

 

Forest fire

 

1. In the cooler tropical region , friction or rubbing among the branches of tree creates fire .

2. Jhum Cultivation

3. Cooking in the forest by the tribes

Conservation of forests 

Rational utilization of forests is called  forest conservation

Ways to conserve resources are as follows

Control on grazing, cutting of forest ,Forest fires.

Afforestation

Grassland regeneration and conservation

Strict implementation of Foerst Laws

Awareness programme like van Mahotsava , wild life week should be promoted

Social forestry should be encouraged .

 

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Geo_Gx @Exam Spell 2023