Soil profile


What is Soil Profile?

The soil profile is where the secrets of the soil and landscape around it are hidden. The soil profile is defined as a vertical section of the soil that is exposed by a soil pit. A soil pit is a hole that is dug from the surface of the soil to the underlying bedrock .If you look in a soil pit or on a roadside cut, you will see various layers in the soil. These layers are called soil horizons. The arrangement of these horizons in a soil is known as a soil profile. Soil horizons differ in a number of easily seen soil properties such as color, texture, structure, and thickness. Other properties are less visible. Properties, such as chemical and mineral content, consistence, and reaction require special laboratory tests. All these properties are used to define types of soil horizons.

Soil horizons

1.Organic Layer (O) and Top Soil (A)

Mostly organic matter such as decomposing leaves. The O horizon is thin in some soils, thick in others, and not present at all in others. Topsoil is often referred to as the organic layer. In this layer, plants grow and animals live on top of the soil. The plants keep the soil cool and from drying out. It also has decomposers that recycle the dead plants and animals. This layer consists of fine textured mineral particles and organic material known as humus. Humus is black and gives the topsoil its color and odor. This layer is very important to life since it is where the plants grow. It is rich in nutrients, oxygen and water. This is the layer that MUST be PROTECTED!

2. Subsoil (B)


 The subsoil layer is about one foot below the surface. Tree roots and earthworms live here. This is a mix of mineral particles and some humus near the top. Subsoil is very low in organic matter compared to the topsoil. A lot of soil nutrients are found in this layer. Deep plant roots come here looking for water. 

3.Parent Rock (C)

This horizon can be very deep. There’s no organic matter here at all. We’re out of reach of all living and dead organisms down here. It’s all rock particles that are full of minerals. This layer may contain rock particles that are different from the bedrock below.

4.Bedrock (R)
We finally find the foundation. Bedrock is the deepest layer that contains nothing but hard, solid rock in it. The bedrock formed the soil above it. It will wait here until erosion or an earthquake exposes it to the surface. Some of it will be weathered to become the next batch of parent material. The soil making process will begin all over again.


Comments

  1. SN kashikola August 17, 2024 at 7:25 AM

    What is the difference between soil profile and soil horizon

    ReplyDelete
    Replies
    1. Victoria NgolotiAugust 20, 2024 at 6:52 AM

      A **soil profile** refers to the vertical section of soil from the surface down to the parent material, showing all the different layers, or horizons, that make up the soil. It gives a comprehensive view of the soil's structure and composition across different depths.

      **Soil horizons**, on the other hand, are the individual layers within a soil profile. Each horizon has distinct physical, chemical, and biological characteristics that differ from the layers above and below it. These horizons are typically labeled as O (organic layer), A (topsoil), E (eluviation layer), B (subsoil), C (parent material), and R (bedrock).

      In summary, the soil profile is the entire sequence of horizons from the surface to the parent material, while soil horizons are the specific layers within that profile.

      Delete
  2. AnonymousAugust 17, 2024 at 7:27 AM

    Well Educated

    ReplyDelete
  3. Martha N ShimhandaAugust 17, 2024 at 7:51 AM

    Right information on Right time

    ReplyDelete
  4. 👂August 19, 2024 at 9:45 AM

    I wish I could change course, well explained notes.

    ReplyDelete
  5. Lucia NghuushiAugust 20, 2024 at 1:13 PM

    This comment has been removed by the author.

    ReplyDelete

Post a Comment

Popular posts from this blog

Image
Types of soil 1.Sandy Soil Sandy soil is coarse in texture with large ,gritty particles .Like the name suggests, sandy soil is mostly made up of sand. Because of the fine grains, water drains easily through this soil and makes it stays pretty dry. It is an easier soil to dig with but it means any plants growing here will need to be well watered. It usually has less organic material in it so needs fertilizer to provide any plants with nutrients  . Sandy soil tends to warm up quickly in the spring because of its light color and the fact that it does not hold much moisture. This can be advantageous for early planting but also means it can overheat and dry out in the summer. Sandy soil is usually formed by the breakdown or fragmentation of rocks like granite , limestone and quartz. 2.Loam Soil Loam soil is known for its ideal balance of the three primarily soil particles: approximately 40% sandy, 40% silt and 20% clay. This balance gives loam a smooth crumby texture that is easy to work wi
Read more
Image
  Ruminant Animals Many different species of ruminant animals are found around the world. Ruminants include cattle, sheep, goats, buffalo, deer, elk, giraffes and camels. These animals all have a digestive system that is uniquely different from our own. Instead of one compartment to the stomach they have four. Of the four compartments the rumen is the largest section and the main digestive centre. The rumen is filled with billions of tiny microorganisms that are able to break down grass and other coarse vegetation that animals with one stomach (including humans, chickens and pigs) cannot digest. Ruminant animals do not completely chew the grass or vegetation they eat. The partially chewed grass goes into the large rumen where it is stored and broken down into balls of “cud”. When the animal has eaten its fill it will rest and “chew its cud”. The cud is then swallowed once again where it will pass into the next three compartments—the reticulum, the omasum and the true stomach, the aboma
Read more
Image
  Different Farming Systems 1.Monoculture Monoculture is the the agricultural practice of growing of a single type of crop a large area for consecutive seasons or years. This method is widely used in modern industrial agriculture due to to its efficiency in producing large quantities of a single crop such as corn, wheat or soybeans. For example, in the northern part of Namibia, people repeatedly cultivate mahangu on the same field season after season. Advantages of Monoculture Efficiency and Specialization Monoculture allows farmers to specialize in one crop, leading to more efficient farming practices. This specialization often results in higher yields because the techniques, machinery and resources are optimized for that specific crop. Simplified Farming Operations  Since only one crop is grown, tasks like planting, harvesting, and pest control become more straightforward. It also allows for the use of specialized machinery, reducing labor costs and time spent on these operations. In
Read more