Plus, get practice tests, quizzes, and personalized coaching health lesson plans and soil help you succeed. Login here for access. Log in or sign up to add this lesson to a Custom Course. Login or Sign up. Gillaspy has taught health science at University of Phoenix and Ashford University and has a degree from Palmer College of Chiropractic, health lesson plans and soil. Soil varies in its composition and the structure of its particles, and these factors are closely examined by farmers, who need appropriate soil for planting crops, as well as engineers who may need to understand how soil is going to hold up under different demands.
Soil is also vitally important to the sustainability of an ecosystem because it serves as the natural medium for the growth health lesson plans and soil vegetation.
In this lesson, you will discover just what soil is and which factors are looked at when determining the structure and the types of soil. So, what exactly is soil? Soil can be defined as the organic and inorganic materials on the surface of the earth that provide the medium for plant growth. Soil develops slowly over time and is composed of many different materials.
Inorganic materials, or those materials that are not living, include weathered rocks and minerals. Weathering is the mechanical or chemical process by which rocks are broken down into smaller pieces. As rocks are broken down, they mix with organic materials, which are those materials that originate from living organisms. For example, plants and animals die and decompose, releasing nutrients back into the soil.
Now, if health lesson plans and soil look down at the soil under your feet, you cannot tell very much about that soil, health lesson plans and soil.
Each layer of a soil profile is referred to as a soil horizon. These horizons are identified by letters. Horizon A is the upper layer, closest to the surface.
You can think of this horizon as the topsoil. In fact, you can use this as a memory jogger to help remember the order of the horizons. The letter A is at the top of the alphabet and refers to the topsoil layer. As you move deeper into the layers of the soil profile, you have horizons B and C, giving us the three main horizons. There are three basic types of soil: But, most soils are composed of a combination of the different types. How they mix will determine the texture of the soil, or, in other words, how the soil looks and feels.
One type of soil is sand. Sand within soil is actually small particles of weathered rock. Sand is fairly coarse and loose so water is able to drain through it easily. While this is good health lesson plans and soil drainage, it is not good for growing plants because sandy soil will not hold water or nutrients. Silt is another type of soil. Silt can be thought of as fine sand, and it will hold water better than sand. If you were to hold a handful of dry silt in your hand, it would feel almost like flour.
Health lesson plans and soil you were to add water to the silt in your hand, it would do a fair job of holding the water and feels slick and smooth. Clay is very fine-grained soil, health lesson plans and soil. Its particles are even smaller than silt, so there is very little space between the fine grains for air or water to circulate.
Therefore, clay does not drain well or provide space for plant roots to flourish. If you were a farmer, you would not want your field to be mostly clay. However, if you were a potter, you would think clay was the best type of soil.
When moisture is added to clay, it can be molded into shapes, such as a pottery bowl or papillo virus and cervical cancer building brick. Now, we can consider loam as our fourth type of soil, even though it is really a combination of sand, silt and clay. Loam will vary depending on how much of each component is present, but generally if you are a gardener, this is the type of soil you want because it holds moisture, but also allows for good drainage.
If you were to hold loam in your hand, you could mold it into a ball, but the ball would easily crumble when disturbed. Get FREE access for 5 days, just create an account. So, health lesson plans and soil, we learned about the types of soil. This told us about the texture, which really comes down to the size of the particles and how much of each particle is present.
Now we can turn our attention to soil structure. The soil structure is based on the arrangement of individual particles of sand, health lesson plans and soil, silt and clay. When we have these individual soil particles bound together, they form soil aggregates. These aggregates form distinct shapes, and we want to know about these shapes because they tell us how easily water will penetrate down through soil. For example, if the soil structure is granular, then it is made up of small crumbs of soil.
Water will easily drain down past these small structures, and therefore, granular structure is a good medium for drainage and aeration. However, health lesson plans and soil, if the soil structure is platy, then we see a horizontal plate-like structure to the soil particles, health lesson plans and soil.
This makes water draining down from the surface take a windy, slow path around the plates, making for poor water and air circulation. Platy structure is common in highly compacted soil, such as forest soil and lake sedimentation. We also have columnar or prismatic structures, which have long vertical dimensions that look like columns of soil.
These structures are very dense, health lesson plans and soil, and penetrating water has to work fairly hard to travel through health lesson plans and soil structure. Blocky structure is, as you might have guessed, a block-like structure. If the blocks are large, then water penetration and movement of water will not be good due to the fact that the water must flow around the blocks as opposed to taking a more direct route downward. Soil is the organic and inorganic material on the surface of the earth that provides the medium for plant growth.
A soil profile is a vertical section of soil that ranges from the surface to the underlying rock. A layer of a soil profile is referred to as a soil horizonand we see that there are three main horizons named using the capital letters A, B and C. There are different types of soil based on the size of the particles and how much of each particle is present.
One type of soil is sandwhich is small particles of weathered rock. Sand is fairly coarse and loose, so water is able to drain through it easily. Silt is fine sand, and the particle size is in between sand and the next type of soil called clay. Clay is very fine-grained soil with particles that are even smaller than silt.
Clay does not drain well. Loam is a combination of sand, silt and clay. Loam is the best soil for gardening because it holds moisture, but also allows for good drainage. Soil structure is based on the arrangement of individual particles of sand, silt and clay. Soil aggregates is the term used to describe the individual soil particles bound together.
These aggregates form distinctive shapes and tell us how easily water will penetrate down through the soil. A granular structure is made up of small crumbs of soil that are easy for water to penetrate; whereas a platy structure is a horizontal plate-like structure that requires water to take a windy, slow path.
Other soil structures include columnar or prismatic structures, which have long vertical dimensions, and blocky, which has a block-like structure. Water has to work fairly hard to travel through these structures. To unlock this lesson you must be a Study. Become a member to get your questions answered by our experts. Start your 5-day FREE trial now to try it today!
If you have other phentermine thyroid and hair loss, we encourage you to please check out our knowledge base of Frequently Asked Questions FAQs or submit a question to customer support directly, health lesson plans and soil. We look forward to hearing from you! Did you national football league and retirement plan We have over college courses that prepare you to earn credit by exam that is accepted by over 1, colleges and universities.
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The videos on Study. Students in online learning conditions performed better than those receiving face-to-face instruction. By creating an account, you agree to Study. Explore over 4, video courses. Find a degree that fits your goals. Soil varies due to its structure and composition. Learn about the different types of soil and soil structures in this video lesson. An error occurred trying to load this video. Try refreshing the page, or contact customer support. Register for a free trial Are you a student or a teacher?
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