The Importance of Soil
The Importance of Soil • The history of Soil
– Dates back all the way to the Egyptians civilization of 4,000 years ago
– Recently in the US history supplies another example of soil misuse. This is with the Dust bowl of the 1930’s.
– The Dust bowl was a drought that misused the soil in having wind erosion.
The Importance of Soil • Additional acreage is lost due to urbanization
or degradation . • Soil is a nonrenewable resource
The Importance of Soil • Most of the time we take soil for granted. • Soil is a very thin and often fragile layer of life
The Importance of Soil • Facts about the earth
– Earth consists of solid part (core, mantle, and crust) and the atmosphere surrounding it.
– Most of the earth is covered by sea – Where continents exist the crust is thicker – This is usually about 50 miles thick
The Importance of Soil • The atmosphere is about 170 miles deep. • The soil forms a very thin interface between
The Importance of Soil • What does living things need?
– Proper temperature – Oxygen – Water – Carbon – Other nutrients – These factors are exchanged in the soil that
allow elements to be recycled rather than lost
The Importance of Soil • Oxygen:
– Plant roots need oxygen to grow.
– Gases will pass in and out of the soil to supply the
oxygen for the roots
The Importance of Soil – Temperature
• Plants will grow best in certain soil temperature ranges. • Most plants will root in temperature around 40-50
• Water: – Seldom stays in one place
The Importance of Soil • Carbon:
– Plant leaves collect sunlight to use the energy in the process of photosynthesis.
– Which involves converting atmosphere carbon to biological carbon
– Atmosphere carbon = carbon dioxide – Biological carbon = simple sugars
The Importance of Soil • Nutrients :
– Plant nutrients are chemicals a plant needs to grow.
– There are two types of nutrients cycles • Nitrogen cycle • Mineral cycle
The Importance of Soil • Nitrogen:
– Comes directly from the atmosphere where it occurs as a gas that plants cannot use.
4 Needs of Soil • There are four needs of the soil
4 Needs of Soil • Anchorage:
– This is where plants grow freely and are firmly supported or anchored so they can grow to reach the sunlight.
– Water: – Soil will provide the plants with all the water
the plant needs – Roots are the best water absorbing body .
4 Needs of Soil • Oxygen:
– Call creature even plants need oxygen. Plants release oxygen during photosynthesis but consume it during respiration.
4 Needs of Soil • Nutrients:
– There are 16 nutrients usually considered to be needed for plants.
– Plants obtain 13 of the 16 nutrients from the soil itself.
– Other nutrients come from Air and water. • Carbon • Oxygen • hydrogen
3 phase system • What is soil Matrix?
– It is the arrangement of solid particles and pore spaces which consists of three phases of solid , liquid, and gases.
3 phase system • The ideal Soil Type:
– 50% solid material – 45 % mineral particles – 5% organic matter – 25% water – 25% gases
3 phase system • Root Growth:
– Water reaches the root by two ways • Either water flows toward the root • Or the root grows into moist soil
Ag Uses of Soil • Humans depend on soil to grow food, fiber,
timber, and ornamental plants.
• Most Ag uses require different soil types and management practices
4 Types of Ag Uses • 1. Cropland:
– Cropland is land which soil is worked and crops are planted, cared for, and harvested.
– Crops that are grown • Annual crops are corn and soybeans • Fiber crops are cotton horticultural crops like
4 Types of Ag Uses • Annual Crops:
– Require yearly soil preparation
– Perennial Forages: – Are alfalfa. – Which are crops that are in the ground for a few years – These crops keeps the soil completely cover and keeps
the soil in place.
4 Types of Ag Uses • Perennial Hort. crops:
– This includes fruits, nuts, and nursery stock
4 Types of Ag Uses • 2. Grazing Land:
– Much of the land in the US is grazed by cattle and sheep
4 Types of Ag Uses • 3. Forest
– Foresters probably disturb soil the least,
– 4. Other Uses – This usually deals with growing plants in tiny pots and
usually with Landscapers
Non Ag Uses of Soil • A few of the Non Ag uses of soil are:
– Recreation – Foundations – Waste Disposal – Building Materials
Non Ag Uses of Soil • Recreation:
– Recreational uses of the soil can be: • Sitting in a urban park and seeing kids play on the
playground, softball diamond, • They can also be golf courses, campgrounds. • Most demanding recreational use is the use of playing
fields. As most of the time there is a demand to have good grow on turf that can with stand about anything.
Non Ag Uses of Soil • Foundations:
– A good builder usually will have the soil tested to a dept of several feet.
– The structural soundness of a building depends on the amount of soil that is under the building.
Land Uses in the US • 27% is in rangeland • 26% is in cropland • 27% is in forestland • 2% is in conservation reserve land • 4% is in other land • 6% is in urban land • 8% is in pastureland