Zusammenfassung der Ressource
Formation of Soil
- Five major influences on soil
formation
- nature of the original parent
material, weathering, climate, land
surface features, and the action of
plants and animals
- These factors determine the physical and
chemical properties of various kinds of soil.
- Temperature and precipitation are the main
weathering and climatic factors that affect
soil development.
- Parent material is the basic
mineral and organic
material from which the soil
is formed.
- There are three kinds of
parent material:
transported, residual, and
organic.
- The residual parent material from
which soil is formed is loose, slightly
weathered rock called regolith.
- The greater the weathering
processes at work, the finer the
particles of soil that result.
- These particles
range from gravel
to sand, silty
material, and,
finally, clay.
- Soil is enriched by the wastes
and decayed bodies of animals.
- Many insects directly enrich
the soil by fertilizing flowers,
thus aiding the spread of
plant life.
- Some animals—ants and
earthworms, for example—help
by mixing the soil.
- Plants and
animals also
help
develop soil.
- Land surface features affect soil development
by controlling the amount of erosion of topsoil
and by influencing how water drains into the
soil.