SEMINOR PRESENTATION ON SOIL TYPE & THEIR CHARACTERISTIC by rudra narayan singh under guide : er. K.c das h.o.d civil department

ajay binay institute of TECHNOLOGY, CUTTACK -753010

CONTENT

Introduction.What Is Soil.Origin of Soil Composition of soil.Type Of Soil & their characteristics.Conclusion.

Introduction

The term ‘soil’, which has originated from the Latin word “solum” has diff meanings to different professional groups. To an agriculturist, it means loose material laying on earth’s surface, formed by disintegration of rocks, which can support plant life. To civil engineer, it means all the inorganic material on the earth’s surface, produced by weathering of rocks, being either residual or transported.

The study of soil, its behavior and application as the engineering material is known as soil mechanics.

Terzaghi is the “father of soil mechanics”.

What Is Soil

Soil is the mixture of mineral, organic matter, gases, liquids, and the countless organisms that together support life on earth.

It is the unaggregated or uncemented deposits of mineral and/or organic particles or fragments covering large portion of the earth’s crust.

It includes widely different materials like boulders, sands, gravel, clays, and silts and the range in the particle sizes in a soil may extend from grains only a fraction of micron (10~-4) in diameter up to large size boulders.

Origin Of Soil

Geological cycle of soil formation

Erosion

Transportat

ion

deposition

Upheaval

Composition Of Soil

Soil is composed of both organic & inorganic matter, and it is essential for life on earth to exist. The soil type I have studied is brown earth. Brown earth are most common soil type in Ireland and are very fertile. Soil are a composition of mineral particles45%, organic matter 5%, air25%, and water25%.

1. Mineral Particle-: It is the largest ingredient and make up approx 45%

of soils. They are the original rock that got broken down by weathering and erosion to form the basis of soil.

Composition Of Soil

2. Air & water -:Air is vital for the survival of micro- organisms and

without these, there would be a shortage of human. brown earth have a granular structure which allow for good aeration. Plants cannot survive without water present in the soil.

3. Texture -:It means that how a soil feels after touching.The proportion of sand, silt, and clay determine the soil

texture. The ideal combination for soil texture is roughly 40% sand, 40% silt, 20% clay, creating what is known as a loam soil.

Composition Of Soil

4. Organic matter-:Organic matter is decayed vegetation that is broken

down by micro organisms in the soil to form human it consist up aproxx 5%.

5. Colour -:Lighter colored soils deflect sunlight while dark soils

absorb more light. This allows the soil to heat up much more quickly and encourages seed germination and crop growth.

6. Ph Value -:It measure the acidity of a substance. The ideal ph value

for agriculture is 6.5 which is slightly acidic.

Characteristics of

Different types of soils

TYPE OF SOIL

There are mainly 15 type of soil which we know about these are -:

1. Black Soil2. Red Soil3. Late rite Soil4. Desert Soil5. Mountain Soil6. Saline Soil & Alkaline Soil7. Peaty & Marshy Soil 8. Cohesive Soil

TYPE OF SOIL

9. Residual Soil10. Alluvial Soil11. Marine Soil12. Aeolian Soil13. Loam Soil14. Clay Soil15. Glacial Soil

Black Soil

BLACK SOIL Also known as Regur or Black Cotton soil. Dark grey to Black in color. High clay content. Highly moist retentive. Develops cracks in summer. Covers 5.4 lakh sq. km. Highly suitable for cotton. Rich in iron, lime, calcium,Magnesium,carbonates, and alumina.

Red soil

RED SOIL Formed due to weathering of old crystalline rocks. More sandy and less clayey. Rich in iron, small amount of Humus. Poor in phosphorus, nitrogen and lime. Slightly acidic and do not retain moisture. 3.5 lakhs sq.km area. Porous and Friable.

Laterite soil

LATERITE SOIL Latin word meaning brick. Formed under high temperature and rainfall with wet and dry spell. Silica is leached due to high rainfall. Remnants of iron and aluminum oxides left

behind is know as Laterite. Brown to Yellowish color. Becomes hard when exposed to atmosphere. Used as building material.

Desert soil

DESERT SOIL Contains soluble salts. Originated by Mechanical disintegration & wind deposit. Porous and coarse. 90% sand & 5% clay. Rich in Nitrates & Phosphates. Poor in Nitrogen & Humus. Friable, sandy & low moist content. 1.4 Lakh sqkm.

Mountain soil

MOUNTAIN SOIL Found in hill slopes. Formed by deposition of organic matter from forest. Rich in humus. Poor in Potash and Lime. Areas: Assam, Kashmir, Sikkim & Arunachal Pradesh. Crops: Tea, Coffee, Spices & Tropical Fruits.

Saline & Alkaline soil

SALINE & ALKALINE SOIL Contains salts like Sodium, Magnesium, Calcium. Infertile, unfit for cultivation. Sandy to loamy in texture. Areas: Parts of Gujarat, Rajasthan, Punjab, Haryana, U.P & Maharashtra.

Peaty & Marshy soil

PEATY AND MARSHY SOIL Occur in Humid region. Formed by accumulation of organic matter. Black in colour. Highly acidic and heavy. Areas: Kottayam & Alleppey in Kerala, Coastal Orissa, Sundarbans of W.B

Cohesive soil

A sticky soil, such as clay or silt; its shear strength equals about half its unconfined compressive strength.Soil in which the absorbed water and partical attraction act such that it deforms plastically at different water Contents are known as Cohesive soils or clays. These soils possess higher plasticity . e.g. clays & plastic silt.

Residual soils

Residual soils are those that remain at the place of their formation as result of the weathering of the parent rocks. The depth of residual soils depends primarily on climatic conditions and the time of espouser. In temperate zones residual soils are commonly stiff and stable. An important characteristics of residual soil is that the sizes of grains are indefinite.

Alluvial soil

ALLUVIAL  soil  is  formed  when  a  soil-carrying  stream  gradually  loses  its  carrying capacity   with   decreasing   velocity.   In   slowing down,  a  river  does  not  have  sufficient  power  to keep the large particles of soil suspended; these particles settle to the riverbed. Further decrease in velocity causes smaller particles to settle. These particles are deposited, finally, at the mouth of the river, where they form DELTAS of fine-grained soil.

Marine soil

MARINE soil is formed   from materials carried into the seas by streams and by material eroded from the beaches by the tidal action of the waves.  Part  of  the  material  is  carried  out  and deposited in deep water; part is heaped upon the beaches  along  the  coast

Aeolian soil

A type of soil that is transported from one place to another by the wind.e.g sand dunes,loess.

Loam

Loam is soil composed of sand, silt, and clay in relatively even concentration (about 40-40-20% concentration respectively).[1]

 Loam soils generally contain more nutrients

and humus than sandy soils, have better infiltration and drainage than silty soils, and are easier to till than clay soils. Loams are gritty, moist, and retain water easily.

Clay

Clay is a naturally occurring aluminium silicate composed primarily of fine-grained minerals. Clay deposits are mostly composed of clay minerals, a subtype ofphyllosilicate minerals, which impart plasticity andharden when fired or dried; they also may

contain variable amounts of water trapped in the mineral structure bypolar attraction. Organic materials which do not impart plasticity may also be a part of clay deposits.

Glacial soil

Glaciers carry with them soils varying in size from fine grained to huge boulder. Soil get mixed with the ice and are transported far away from their original position. Drift is a general term used for the deposits made by glaciers