h. Describe soil as h. Describe soil as consisting of consisting of

weathered rocks and weathered rocks and decomposed organic decomposed organic

material. material.

Essential QuestionEssential Question

What are the What are the scientists called scientists called that study soil?that study soil?

Soil FormationSoil Formation

Soil LayersSoil Layers

PedologistPedologist

SoilSoil is is formed slowly as rock as rock ((parentparent materialmaterial) erodes into ) erodes into tiny pieces near the Earth’s tiny pieces near the Earth’s surfacesurface. . BedrockBedrock is the layer of is the layer of rock just beneath soil.rock just beneath soil.

Soil is made up of distinct Soil is made up of distinct horizontalhorizontal layers called layers called horizonshorizons. Range: organic . Range: organic upperupper layers to underlying layers to underlying rockyrocky layers. layers.

What is loam?What is loam?

Soil composed of Soil composed of sand, silt, and sand, silt, and clay clay in relatively even concentration in relatively even concentration

Soil Properties: Soil Soil Properties: Soil TextureTexture

Definition: the soil quality that is based Definition: the soil quality that is based on the on the proportionsproportions of soil of soil particlesparticles..

Affects the Affects the soil’ssoil’s consistency consistency– The The soil’s ability to be worked and soil’s ability to be worked and

broken up broken up for for farmingfarming Influences infiltrationInfluences infiltration

– Ability of water to Ability of water to movemove through the through the soilsoil

– Also known as Also known as percolationpercolation

Soil Properties: Soil Soil Properties: Soil StructureStructure

Definition: the Definition: the arrangement arrangement of of soil particlessoil particles

Often one type of soil Often one type of soil particlesparticles will clump in one area, which can will clump in one area, which can blockblock the flow of water through the flow of water through the soil affecting soil the soil affecting soil moisture.moisture.

Soil LeachingSoil Leaching

Soil leaching refers is the Soil leaching refers is the movementmovement of of nutrientnutrient elements from topsoil through elements from topsoil through the soil profile. Leaching the soil profile. Leaching causes significant causes significant nutrientnutrient losseslosses, particularly in humid , particularly in humid regions with high precipitation. regions with high precipitation. Leaching is a natural process Leaching is a natural process causedcaused mainly by mainly by precipitationprecipitation, acidification , acidification and nitrogen saturation.and nitrogen saturation.

Soil Properties: Soil FertilitySoil Properties: Soil Fertility

Definition: soil’s ability to Definition: soil’s ability to hold hold nutrientsnutrients and to supply and to supply nutrients to a nutrients to a plantplant

Soils vary in the Soils vary in the amountamount of of nutrients it contains. Plants nutrients it contains. Plants need need nutrientsnutrients (such as (such as IRONIRON) to grow) to grow..

Soil pHSoil pH Soils can be Soils can be acidicacidic or or basicbasic pH pH scalescale

– Used to Used to measuremeasure how acidic or how acidic or basicbasic a soil is and ranges from a soil is and ranges from 00 to to 1414..

– The midpoint The midpoint 77 is neutral. is neutral. Above 7= Above 7= basicbasic. . Below 7= Below 7= acidicacidic..

The pH of a soil influences how The pH of a soil influences how nutrientsnutrients dissolve dissolve in the soil.in the soil.

Soil HorizonsSoil Horizons

Summarize the Summarize the