soil not just dirt n.
Skip this Video
Loading SlideShow in 5 Seconds..
Soil : Not Just ‘ Dirt ’ PowerPoint Presentation
Download Presentation
Soil : Not Just ‘ Dirt ’

Loading in 2 Seconds...

play fullscreen
1 / 33

Soil : Not Just ‘ Dirt ’ - PowerPoint PPT Presentation

  • Uploaded on

Soil : Not Just ‘ Dirt ’. What is Soil ?. Soils are a major component of the world’s ecosystems. They form at the interface of the Earth’s atmosphere , lithosphere (rocks), biosphere (living matter) and hdyrosphere (water). What is Soil ?.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Soil : Not Just ‘ Dirt ’' - feo

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
what is soil
What is Soil?

Soils are a major component of the world’s ecosystems.

They form at the interface of the Earth’s atmosphere, lithosphere (rocks), biosphere (living matter) and hdyrosphere (water).

what is soil1
What is Soil?

Soil is what forms the outermost layer of the Earth’s surface.

Soil comprise weathered bedrock (regolith), organic matter (both dead and alive), air and water.


what is soil2
What is soil?
  • Soil has matter in all three states:
  • organic and inorganic matter form the solid state
  • soil water form the liquidstate (precipitation, groundwaterandseepage)
  • soil atmosphere forms the gaseous state
functions of soil1
Functions of soil
  • Soils are important to humans in many ways:
  • soil is the medium for plant growth, which most of foods for humans are grown in
  • soil stores freshwater, 0.005% of world’s freshwater
  • soil filters materials added to the soil, keeping quality water
functions of soil2
Functions of soil
  • soil is nature’s recycling system. Waste and dead matter are decomposed and their nutrientsmade available for new life.
  • soil is the habitat for billions of micro-organisms, as well as other larger animals
  • soil provides raw material in the forms of peat, clay, sands, gravel and minerals
functions of soil3
Functions of soil

Soils breathe!

Gases are exchanged between the soil surface and the air. Gases like oxygen andmethane are absorbed, while, while gases like carbon dioxide and nitrous oxide are released. The soilprovides a valuable carbon sink. The evaporation of soil moisture also affects air temperature andweather patterns.

soil biology

Soil is by far the most biologically diverse part of the earth.

It containsa complex food web of prey, predators and decomposers.

Theseorganisms require the same elements we require: air, water, foodand shelter.

soil biology2

One teaspoon of healthy soil may contain:

• Bacteria- 100 million to 1 billion

• Fungi- up to 100 yards of fungal hyphae

• Protozoa- several thousand

• Nematodes- up to several hundred

• Arthropods (insects,spiders,centipeds)-500-2000

• Earthworms-arid soils may have none to several

soil horizons1

O – Organic Horizon:

l - undecomposed litter

f – party decomposed litter

h – well decomposed humus

soil horizons2

A – Mixed mineral-organic Horizon:

h – humus

p – ploughed in field or garden

g – gleyed or waterlogged

soil horizons3

E - Eluvial or leached Horizon:

a – strongly leached,

and ash coloured

b – weakly bleached,

light brown

soil horizons4

B – Illuvial or deposited

Fe – iron deposited

t – clay deposited

h – humus deposited

soil horizons5

C – Bedrock or parent material

r – rock

u – unconsolidated loose


formation of soil
Formation of soil

Soil is formed from rocks and decaying plants and animals.

Soil forming process consists of:

  • Gains and losses of material to and from the profile
  • Movement of water between the horizons
  • Chemical transformation within each horizon


formation of soil1
Formation of soil

Therefore soils are open systemsin a steady-state equilibrium

formation of soil2
Formation of soil
  • Theprincipleprocessesinclude
  • Weathering
  • Translocation
  • Organicchanges (degradation, humification,
  • mineralization)
  • Gleying (waterlogging)
soil formation

Natural processes can take 500 years to form one inch of top soil.

Soils are vital to humans, but take a long time to develop, so should be considered a non-renewable resource

value of soil
Value of Soil

“The soil is the great connector of lives, the source and destination of all. It is the healer and restorer and resurrector, by which disease passes into health, age into youth, death into life. Without proper care for it we can have no community, because without proper care for it we can have no life.” ― Wendell Berry, The Unsettling of America: Culture and Agriculture



Symphony of Soil

Dirt: The Movie


A littleresearch……..

  • What is pedology?
  • What is compost?
  • How tomakecompost? Is it possibleto
  • makecompost at homeor at school?