factors affecting soil formations class 8th

1. Powerpoint Presentation to depict factors affecting soil formations

2. Five factors involved in soil formation
❖ There are five primary factors that affect the
process of soil formation and development.
Parent material—type of rock material the soil is
formed from.
Climate—temperature and moisture characteristics
of the area in which the soil was formed.
Living organisms—the organisms, including plant
material, that live within the soil.
Time or weathering—age of the soil and its climate

4. SOIL FORMATION
a. Soil formation is the combined effect of physical,
chemical, and biological processes on soil parent
material.
b. Soil genesis involves processes that develop
layers or horizons in the soil profile.
c.These processes involve additions, losses,
transformations and translocations of material that
compose the soil.
d.The weathering of bedrock produces the parent
material that soils form from.

5. Parent material
Parent materials are formed by the disintegration and decomposition of rock. They
are classified according to the way they were moved and scattered. Many soils have
been formed from material originally moved by glaciers. Soils of glacial origin are
classified as follows:
TYPES OF PARENT MATERIAL
1. Loess—occurred from the blowing of the soil after the glaciers melted and dried.
2. Outwash—occurred when the glaciers melted. The melt waters carried the gravelly
materials away to be deposited below the glacial ridges. Sandy outwash was carried
further downstream and the finer materials, silt and clay, were deposited in
lakebeds or slow moving water along streams.

6. TYPES OF PARENTS MATERIAL
3. Glacial till—have not been layered from the
effects of wind or water as the other two types
of glacial soils. It often contains a variety of
sizes of soil particles. Pebbles and various
sizes of boulders are common in till..
Some soils are formed as a result of recent
sediments deposited by streams as they flood. It
is referred to as alluvium. Alluvium is generally
a water-borne material deposited on bottomlands

7. TYPES OF PARENT MATERIAL
Bedrock—shale, sandstone, or limestone bedrock; weathered
bedrock can provide soil parent materia
Organic matter—occur where formerly shallow ponds supported
swamp vegetation. The wet conditions slowed decay of the dead
plants so that organic matter could accumulate. The two types
of organic soils are referred to as peat and muck. Muck is
more decomposed than peat.

8. Parent material effect
The parent material of a soil determines the original supply of
those nutrient elements that are released by weathering and
influences the balance between nutrient loss and retention.
Organic acids and exudates produced by microorganisms and
plants enhance the weathering of minerals and the release of
nutrients

9. topography effect
Topography has a strong influence on soil development. Soils on the side
of hills tend to be shallow, due to erosional losses. Soils on the tops of hills
tend to be deep, but lighter in color, due to downward leaching losses.
Soils in the valleys tend to be deeper, darker, and contain more horizons.
This is due to increased material deposition from hillside erosion, material
accumulation from downward leaching from the tops of hills, and the
collection of greater quantities of water in the low lying areas.

10. Climate effects
Climate: Temperature and moisture influence the speed of
chemical reactions, which in turn help control how fast
rocks weather and dead organisms decompose. Soils
develop faster in warm, moist climates and slowest in cold
or arid ones. Rainfall is one of the most important climate
factors in soil formation.

11. Living organisms effect
Living organisms affects soil formation by producing or contributing
to humus production.
Plants, animals, micro-organisms, and humans affect soil formation.
Animals and microorganisms mix soils and form burrows and pores.
Plant roots open channels in the soils. Organisms decompose these
leaves and mix them with the upper part of the soil.