Natural ResourcesConservation Service

Helping People Help the Land

Introduction Introduction to Soilto Soil

Do NowDo Now

1.1. Write down what you Write down what you think the difference is think the difference is between soil and dirtbetween soil and dirt

2.2. List as many reasons List as many reasons you can think of why you can think of why soil is importantsoil is important

Careers in Soil ScienceCareers in Soil Science

Soil and Plant ScientistSoil and Plant Scientists from Careers.orgs from Careers.org

SOILSOIL

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

SOILSOIL

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

DirtDirt

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

Importance of SoilImportance of Soil

Foundation for roads and structuresFoundation for roads and structures Home to plants and animalsHome to plants and animals Grow things in itGrow things in it Contains and filters waterContains and filters water Helps dispose of wasteHelps dispose of waste Basis for recreation areasBasis for recreation areas

Soils Perform Several Vital FunctionsSoils Perform Several Vital FunctionsSustaining plant and Sustaining plant and animal life below and animal life below and above the surfaceabove the surface

Regulating and Regulating and partitioning water and partitioning water and

solute flowsolute flow

Filtering, buffering, Filtering, buffering, degrading, immobilizing, degrading, immobilizing, and detoxifyingand detoxifying

Storing and cycling Storing and cycling nutrientsnutrients

Providing support to Providing support to structuresstructures

Soil Studies Can Be IncorporatedSoil Studies Can Be IncorporatedInto Other StudiesInto Other Studies

ScienceScienceecology, biology, chemistryecology, biology, chemistry

Social StudiesSocial Studiesworld trade, land useworld trade, land use

MathematicsMathematicssoil loss over one hectaresoil loss over one hectare

HistoryHistorysettlement of the U.S., dust bowlsettlement of the U.S., dust bowl

ArtArtsoil crayons, acrylic paintssoil crayons, acrylic paints

SOILSOIL

Mixture of Mixture of mineral matter, mineral matter, organic matter, organic matter, water, and air.water, and air.

Properties of soilProperties of soil

Air 25%

Mineral Matter 45%

Water 25%

Organic Matter 5%

SOIL COMPONENTSSOIL COMPONENTS

3 Fractions of Mineral Matter3 Fractions of Mineral Matter

SandSand

SiltSilt

ClayClay

Soils Are AliveSoils Are AliveOrganism TypesOrganism Typesbacteriabacteriafungifungiprotozoaprotozoanematodesnematodesarthropodsarthropodsearthwormsearthworms

Roles & BenefitsRoles & Benefitsdecompositiondecompositionrelease nutrientsrelease nutrientscreate porescreate poresstabilize soilsstabilize soils

Scientific Names for Soils Should Be UsedScientific Names for Soils Should Be Used

• Like plants and animals, Like plants and animals, soils are classifiedsoils are classified• The The systemsystem is called is called Soil TaxonomySoil Taxonomy• The The highest levelhighest level is the is the soil ordersoil order (12) (12)• The The lowest levellowest level is the is the soil seriessoil series, often a place name, often a place name

USDA Textural Triangle

Soil ColorSoil Color

Indicator of different soil typesIndicator of different soil types

Indicator of certain physical and Indicator of certain physical and chemical characteristicschemical characteristics

Due to humus content and Due to humus content and chemical nature of the iron chemical nature of the iron compounds present in the soilcompounds present in the soil

Want to learn more Want to learn more about soil?about soil?

Visit NRCS’ website at the National Visit NRCS’ website at the National Soil Survey Center at Soil Survey Center at www.soils.usda.govwww.soils.usda.gov

Prepared by Earl D. LockridgePrepared by Earl D. LockridgeNational Soil Survey CenterNational Soil Survey CenterLincoln, NELincoln, NEUSDA NRCS ~ An equal opportunity provider and employerUSDA NRCS ~ An equal opportunity provider and employer

We KNOW Soil!

Natural ResourcesConservation

ServiceHelping People Help the Land