Aim: What makes up soil?

Objective: Demonstrate an understanding of soil formation

Vocabulary: soil profile, humus

What is soil?

Easier Definition:

Soil is the loose top layer of our planet's crust. It is dirt or earth in which plant life can grow.

What is soil?

Harder Definition:

– Harder - Soil covers a major portion of the earth's land surface.

– It is an important natural resource that either directly or indirectly supports most of the planet's life.

– Life here depends upon soil for food.

Harder Definition:– Plants are rooted in soil and obtain

needed nutrients there. Animals get their nutrients from plants or from other animals that eat plants. Many animals make their homes or are sheltered in the soil. Microbes in the soil cause the breakdown and decay of dead organisms, a process that in turn adds more nutrients to the soil.

What’s in it:– Soil is a mixture of mineral (rock) and

organic materials plus air and water. – The contents of soil varies in different

locations and is constantly changing. – Different kinds of soils support the

growth of different types of plants – Soil is formed slowly, but can be

easily destroyed.

What’s is in the organic mixture– Decayed plants and/or animal

parts– Decayed waster products– Also called humus – Fungi and bacteria help break

down organic matter in the soil – Earthworms digest organic

matter, recycle nutrients, and make the surface soil richer.

What’s are some of the layers– Soil and its layers continue down to

the first layer of rock – called bedrock.

– Bedrock is a solid layer of rock. Sometimes the bedrock of the earth is exposed with NO soil covering

– As bedrock is weathered over millions of years, it turns into soil.

The role of lichen

Over millions of years lichens help break down rock into soil

Lichen is a combination of an algae and a fungus

Lichen produce an acid which help that Lichen absorb mineral from the rock since there is no soil present

Soil Profile

A soil profile is the sequence of natural layers in a soil.

The soil profile extends from the surface downward to unconsolidated material.

Most soils have three or more major layers

Topsoil, sand, weather loose rock, bedrock

Soil Profile

A soil profile is the sequence of natural layers in a soil.

The soil profile extends from the surface downward to unconsolidated material.

Most soils have three or more major layers

Soil Profile

Is the soil profile in the Hampton’s the same as the soil profile in a Midwest cornfield?