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Soil. Much more than "dirt". Why is soil important?. Soil is the growing medium for our food Without it we could not survive Soil purifies our waste Soil is home to plants and animals It may take up to 100 years to form one inch of topsoil
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Soil Much more than "dirt"
Why is soil important? Soil is the growing medium for our food Without it we could not survive Soil purifies our waste Soil is home to plants and animals It may take up to 100 years to form one inch of topsoil We are losing so much soil to erosion each year that the lost soil if loaded into dump trucks parked back to back would extend to the moon and back. An earthworm can work a ton of soil a year
Soil is made up of mineral grains. • Water is held between the grains in the pore spaces. • 25% of the soil is air. Oxygen is essential • Organic matter is both coarse and fine. • Bacteria- A thimble of soil can contain 2 billion bacteria, 30 million fungi fragments and 100,000 single cell plants and animals. What makes up soil?
Humus gives the topsoil a rich brown color Leaching takes minerals carried by water to the subsoil Topsoil Subsoil Weathered Bedrock D Bedrock
In a mature soil profile, there are three distinct layers(horizons) of the soil. The undisturbed rock below the soil is called the bedrock. The Ao-horizon consists of the highly decayed organic material referred to as the peat and humus. Humus gives soil horizon A a rich brown color.We see no such brown layer in the Pine Barrens.
In the A horizon, water percolates downward and carries minerals as it goes. This is called “leaching.” Leaching carries minerals down into the lower soil horizons.
The B-Horizon is called the subsoil. This horizon is where the leached minerals from horizon A end up. These leached minerals may color the subsoil. For example, the presence of iron my color the subsoil red. Horizon B-Zone of Accumulation of leached minerals
The C-horizon is called the zone of weathered bedrock. When you have a residual soil, one formed over the original bedrock, the C-horizon resembles the bedrock, but it is weathered. In a residual soil, the bedrock is below the C-horizon.
Fertile soil contains nutrients Fertile soil contains nutrients. There are major nutrients and micro nutrients. Major nutrients make up the bulk of the nutrients in your soil. The most important major nutrients are :Nitrogen, Potassium and Phosphorus. Other major nutrients are :Calcium, Magnesium and Sulfur. Micronutrients are:Manganese, Iron, Copper, Zinc, and Boron. Nutrients need to be balanced and available to the plant's roots. Organic matter is key to helping maintain this balance.