1. h. Describe soil as
consisting of weathered
rocks and decomposed
organic material.

2. Essential Question

3.  What are the scientists  Pedologist
called that study soil?
 Soil Formation  Soil is formed slowly as rock
(parent material ) erodes into
tiny pieces near the Earth’s
surface . Bedrock is the layer of
rock just beneath soil.
 Soil is made up of distinct
 Soil Layers horizontal layers called
horizons . Range: organic upper
layers to underlying rocky layers.

4. What is loam?
 Soil composed of sand, silt, and clay
in relatively even concentration

5. Soil Properties: Soil
Texture
 Definition: the soil quality that is based
on the proportions of soil particles.
 Affects the soil’s consistency
– The soil’s ability to be worked and
broken up for farming
 Influences infiltration
– Ability of water to move through the
soil
– Also known as percolation

6. Soil Properties: Soil Structure
 Definition: the arrangement of soil
particles
 Often one type of soil particles will
clump in one area, which can block
the flow of water through the soil
affecting soil moisture.

7. Soil Leaching
 Soil leaching refers is the
movement of nutrient
elements from topsoil through
the soil profile. Leaching
causes significant nutrient
losses , particularly in humid
regions with high precipitation.
Leaching is a natural process
caused mainly by
precipitation , acidification
and nitrogen saturation.

8. Soil Properties: Soil Fertility
 Definition: soil’s ability to hold
nutrients and to supply nutrients
to a plant
 Soils vary in the amount of
nutrients it contains. Plants need
nutrients (such as IRON ) to
grow.

9. Soil pH
 Soils can be acidic or basic
 pH scale
– Used to measure how acidic or
basic a soil is and ranges from 0 to
14 .
– The midpoint 7 is neutral. Above 7=
basic . Below 7= acidic .
 The pH of a soil influences how
nutrients dissolve in the soil.

10. Soil Horizons

11. Summarize the