Introduction to Soil

Do Now List as many reasons you can think of why soil is important Write down what you think the difference is between soil and dirt List as many reasons you can think of why soil is important

Careers in Soil Science Soil and Plant Scientists from Careers.org

SOIL Geologic definition: Loose surface of the earth as distinguished from solid bedrock; support of plant life not required.

SOIL Traditional definition: Material which nourishes and supports growing plants; foundation of every living thing

Dirt Soil out of place and unable to serve it’s purpose

Importance of Soil Foundation for roads and structures Home to plants and animals Grow things in it Contains and filters water Helps dispose of waste Basis for recreation areas

Soils Perform Several Vital Functions Sustaining plant and animal life below and above the surface Regulating and partitioning water and solute flow Filtering, buffering, degrading, immobilizing, and detoxifying Storing and cycling nutrients Providing support to structures

Soil Studies Can Be Incorporated Into Other Studies Science ecology, biology, chemistry Social Studies world trade, land use Mathematics soil loss over one hectare History settlement of the U.S., dust bowl Art soil crayons, acrylic paints

SOIL Mixture of mineral matter, organic matter, water, and air. Properties of soil

SOIL COMPONENTS Air 25% Mineral Matter 45% Water 25% Organic Matter 5%

3 Fractions of Mineral Matter Sand Silt Clay

Soils Are Alive Organism Types bacteria fungi protozoa nematodes arthropods earthworms Roles & Benefits decomposition release nutrients create pores stabilize soils

Scientific Names for Soils Should Be Used Like plants and animals, soils are classified The system is called Soil Taxonomy The highest level is the soil order (12) The lowest level is the soil series, often a place name

USDA Textural Triangle

Soil Color Indicator of different soil types Indicator of certain physical and chemical characteristics Due to humus content and chemical nature of the iron compounds present in the soil

Want to learn more about soil? Visit NRCS’ website at the National Soil Survey Center at www.soils.usda.gov We KNOW Soil! Natural Resources Conservation Service Helping People Help the Land Prepared by Earl D. Lockridge National Soil Survey Center Lincoln, NE USDA NRCS ~ An equal opportunity provider and employer