Week 1 And 2 Flashcards
How are soils formed?
Weathering, additions, translocation,transformation, losses
What is translocation
Particles and minerals move down within the profile (earthquakes)
What is transformation
Minerals are changed (adding fertilizer)
What is the state soil of CA
San Joaquin series
What are the 4 major components of soil materials?
mineral matter,organic matter, water, and air
What is mineral matter?
Composed of large and small particles, occupies 40-60% of soil volume
What is organic matter ?
Derived from remains of dead plants and animals, it is dark brown and occurs mostly in the surface of soil. 1-5% of dry mass soil
Soil as a medium of plant growth includes:
Physical support, Air regulation, water movement, temp moderation, protection from toxins,supplies essential nutrients
How does soil help with air regulation?
Soil pores allow CO2 to escape and oxygen to enter the root during respiration. Good drainage also helps
How is temperature moderated in soil?
The soil provides insulation and it protects deeper roots from extreme hot or cold conditions that occur at the surface
How does the soil offer protection from toxins?
The soil helps in decomposing and adsorbing organic toxins and provides ventilation for toxic gases
What is soil fertility?
The ability for soil to supply essential nutrients for plant growth when temp and other conditions are favorable
What is soil productivity?
Ability for the soil to produce a certain amount of yield crops under management
What is the O horizon?
Organic material, formed by fallen plants and animals. Undergoes varying physical and biological processes. Dark in color
What is the A horizon?
Also known as the top soil, and it has a friable consistency and is the region for root activity. 20-25 cm deep
What is the B horizon?
Also known as the ILLUVIAL and subsoil. It is formed below the E horizon and it is the zone for accumulation. It has the highest clay content among other horizons
What is the C horizon?
Aka the Parent Material. It is less weathered, does not have soil structure, and it is likely rock material that can also contain partially disintegrated parent material transported by wind or water
What is the E horizon?
Also known as the ELUVIAL horizon. It is the zone of removal and has a light color or bleached appearance. It contains dissolved minerals and clay, and it has a lot of iron
What does physical support do for plant growth?
Provides physical support by anchoring the root system. Deep soil provides better support
What does water movement do for plant growth?
Deep soils store enough water to allow plants to survive longer during the drought conditions
True or false: higher organic matter in soil=more water compared to low organic matter
True
