Soil

SOIL 1) Soil is a non-renewable resource. (#1)

SOIL 2) Soil is comprised of a mixture of rock particles (minerals), decomposed organic materials, minerals, air, and water.

Soil Horizon 3) A soil horizon is a layer of soil with properties that differ from those of the layer above and below it.

Soil Horizons A normal soil profile consists of three layers: (1) Topsoil-Horizon A (2) Subsoil-Horizon B (3) Bedrock-Horizon C, or, if rock is not present, lower subsoil.

Horizon A – Topsoil A horizon is the upper layer of soil. It is often dark in color! Topsoil represents the depth normally plowed or tilled, and contains the most organic matter or decaying plant parts. Humus is present in Horizon A (topsoil).

Humus Where does most humus come from? Plants and Animals Humus – the decayed organic matter in soil. (Dead animals, plants, microorganisms) 6) Decomposing plant and animal material in soil is also known as humus.

Soil 4) Soil is extremely valuable. It is responsible for all of the food that people eat. Soil is considered to be a non- renewable resource because if we do not use good farming technique, we will run out of topsoil.

Good Soil Good soil does more than just grow crops. It also: Provides homes for animals Stores water Provides nutrients for plants 9) Good soil stores water, provides nutrients for plants, and provides homes for animals.

Different Soils 5) Although weathered rock is the basic component of soil, the composition and texture of soil and its fertility and resistance to erosion are greatly influenced by plants and other organisms.

How is soil classified? Soils are classified according to the percentage of sand, silt, and clay they contain.

Soil is not all the same

Three Types of Soil

7) Sandy Soil has the biggest particles does not hold water well and warms and dries out quickly.

7) Loam Soil consists of sand, silt and clay. It is considered to be the perfect soil. It holds water easily and drains well.

7) Clay Soil has lots of clay particles and small air pores. Holds water and drains water poorly.

3 Types of Soil

What do you think? 8) The type of soil that is best for drainage is sandy and the best type for growing crops is loamy.  

Let’s review What is humus?

Let’s review What are the three types of soil?

Let’s review What is a soil horizon?

Let’s Review Which type soil dries out the fastest?

Let’s Review Which type soil drains the best?

Let’s Review Which type of soil is best for growing crops?