Exam Syllabus 2001
Sponsored Links
This presentation is the property of its rightful owner.
1 / 13

Exam Syllabus 2001 3. Biotic System PowerPoint PPT Presentation


  • 92 Views
  • Uploaded on
  • Presentation posted in: General

Exam Syllabus 2001 3. Biotic System major factors and processes influencing the nature of soils ( podsolization, laterization, calcification, salinization, gleying ). What is soil?. “Soil is a natural body

Download Presentation

Exam Syllabus 2001 3. Biotic System

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


Exam Syllabus 2001

3. Biotic System

major factors and processes influencing the nature of soils (podsolization, laterization, calcification, salinization, gleying)


What is soil?

“Soil is a natural body

comprised of solids (minerals & organic matter), liquid and gases that occurs on the the land surface, occupies space, and is characterized by one or both of the following:

horizons that are distinguishable from the initial material as a result of additions, losses, transfers and transformation of energy and matter

or the ability of supporting rooted plants in a natural environment.……


What is soil?

……

The upper limit of soil is the boundary between soil and air, shallow (<2.5m), live plants or undecomposed plant materials.

The lower boundary is arbitrarily set at 200 cm for the purpose of soil classification”

(Keys to Soil Taxonomy, USDA)


Soil profile and horizons

Profile

-all the horizons taken together

Horizons

-layers distinguished from one another on the basis of certain physical & chemical properties


Atmosphere

Hydrosphere

Biosphere

Lithosphere

A soil system - Interactions with other systems

Time


A soil system - Interactions with other systems

Inputs/Factors

Climate

Relief

Organisms

Parent material

Time

Soil properties

Profiles

Horizons

Physical

Chemical

Biological

Soil forming processes

Addition

Transformation

Transfer

Removal


Soil formation – Horizon development processes


Soil formation – Horizon development processes

1. Additions

-organic or mineral materials that are transported into the location where a soil is forming

-When plants die or leaves fall on to the surface they decompose adding organic matter to the soil.

-Mineral materials can be brought by water, ice, wind or human beings.

-Processes: Plant litters and animals dropping

Transportation and deposition by denudation agents

Agrochemical application

Refuse disposal


Soil formation – Horizon development processes

  • 2. Transformation

  • -materials added to the developing soil can occur by chemical and biological processes acting on them

  • -important in the formation of clay and humus structure within the soil

  • -Processes: Weathering

  • Humification

    • Mineralization


Soil formation – Horizon development processes

  • 3. Transfer

  • -involves the movement of soil-forming materials through the developing soil profile

  • -occurs by water running through the soil transferring it from upper to lower portions of the profile

  • -burrowing animals move soil materials within the profile & create passage ways through which air and water can travel

  • -Processes: Translocation / Leaching, Desaliniztion,

    • Desilication, Dispersion, Eluviation, Illuviation,

    • Pedoturbation, Upward movement / Capillarity


Soil formation – Horizon development processes

4. Removal / Losses

-soil forming materials completely removed from the soil profile

-lost in 4 forms: gases, solutes, particulate material & vegetation removal

-Processes: Evapotranspiration

Soil erosion by winds, water or human beings

Harvesting of crops


Example - Oxisol


Example - Aridisol


  • Login