Soil

Question 1

an essential component on Earth that enabled life to exist on the planet and continues to support.

Answer 1

Soil

Question 2

The term pedosphere is derived from the Greek words “” which means soil and “”which means sphere

Answer 2

Pedon and sfaira

Question 3

Soil is composed of

Answer 3

Soil is generally composed of 45% mineral ( gravel, sand. silt and clay), 25% air, 25% water and 5% organic matter ( humus, roots, dead and decaying organisms). These components reflect the processes hat formed the so

Question 4

Is a loose mixture of rock fragments, organic matter, water, and air – that portion of the regolith ( rhegos=blanket, lithos = stone) that support the growth of vegetation

Answer 4

Soil

Question 5

First step of soil formation

Answer 5

Weathering of parent rock into smaller pieces

Question 6

What causes soil to form?

Answer 6

• Rock is broken down by weathering and plant root growth to form sediment
• Some microorganisms, such as bacteria and fungi, decompose the remains of plants and animals

Question 7

What factors determine how long it takes for soils to form?

Answer 7

These factors include parent material, time, climate, plants and animals, and topography

Question 8

The source of the weathered mineral matter from which soil develops. The rate of weathering depends on the structure of the rock and minerals that make up the rock. When the parent material is bedrock, the soils are termed residual so

Answer 8

Parent material

Question 9

By contrast, those developed on unconsolidated sediment are called

Answer 9

transported soil

Question 10

an important component of every geological processes and soil is no exception. The longer a soil has been forming, the thicker it becomes and the less it resembles the parent materia

Answer 10

Time

Question 11

Soil usually develops more quickly in warm, wet areas than in cold, dry areas. The most influential factor in soil formation. Variations in temperature and precipitation determine whether mechanical or chemical weathering prevails

Answer 11

Climate

Question 12

The biosphere plays a vital role in soil formation. The types and abundance of organisms present have a strong influence on the physical and chemical properties of soil. Without a lot of_, soil tends to develop slowly

Answer 12

plants and animals

Question 13

The lay of the land can vary greatly over short distances. Such variations can lead to the development of a variety of localized soil types.

Answer 13

Topography

Question 14

Defined as the relative proportion of the particle sizes in the soil – sand, silt and clay.
- Clay ( <0.002 mm) – smallest particle
- Silt ( 0.002 – 0.005 mm)
- Sand – ( 0.005 – 2.00 mm

Answer 14

Soil Texture

Question 15

Particles larger than coarse grained sand are called_ if they are > 75.00mm

Answer 15

gravel and rock

Question 16

ideal soil for agriculture use since it provides good aeration and drainage properties of large particles with nutrient nutrition and water holding abilities of clay particle

Answer 16

Loam

Question 17

is the superficial or topmost layer of the soil that is primarily composed of decaying organic matter, living organism, and fresh soil. The color of the topmost layer is normally either brown or black due to its organic composition. It is the layer that hosts most of the roots of small vegetation cover like grass and contains about 20% of organic matter

Answer 17

O-Horizon

Question 18

is the second layer of the soil. It is referred to as the top-soil. It is composed of highly decaying organic matter and minerals, and its color ranges from gray to brown. It is the layer that hosts many plants and supports many agricultural and grassland areas. Thus, seed germination and the growth of plant roots take place in this soil layer. It is distinguishable by the different soil types including loam, clay, sand, and silt. It is also the soil layer that is most vulnerable to water and wind erosion

Answer 18

A-horizon

Question 19

This is the third and the thinnest soil layer, and it is lighter in color compared to the A-Horizon. It is termed as the eluviation layer due to the leaching of minerals. As a result, this layer is depleted of aluminum, clay, organic compounds, and other soluble elements. It is mainly made up of silt and sand after losing most of its minerals as they drip down through the soil

Answer 19

E-horizon

Question 20

is the fourth layer and is also referred to as the sub-soil. It is mainly made up of large rocks, clay, and bedrock. The color of the sub-soil is lighter than the layers above it and ranges from rust to tan. It is also composed of minerals and little organic matter. The sub-soil accumulates a lot of clay, aluminum, iron, and organic compounds from the layers above it from the dripping down of mineralized water through a process known as illuviation. Hence, it is sometimes called the illuviation zone. It is the layer where the roots of big trees en

Answer 20

B-horizon

Question 21

This is the fifth layer of the soil and it also known as the regolith. Plant roots do not go through this layer and it has very little organic matter. The color of the_ is gray and is made up of fragmented pieces of bedrock. Also, it has compacted sediment and cemented geological material. Very little activity is present in this layer but there may be instance of additions or losses of minerals and other soluble compounds.

Answer 21

C-Horizon

Question 22

The_ is the sixth and final layer of the soil. It is also known as the bedrock. The materials here are mainly solid un weathered rock that are cemented and compacted by the weight of the overlying layers. The color of this layer is gray with several hard rocks. This layer is beyond 50 meters from the top-soil. Some of the rocks found here include granite, limestone, and basalt

Answer 22

R-Horizon

Question 23

describes the relative amounts of differently sized soil particles

Answer 23

Soil texture

Question 24

Soil properties are used to classify different soil

Answer 24

These properties include soil texture, color, chemistry, pore space, and fertility

Question 25

Soil particles are classified as

Answer 25

sand (largest particles), silt, or clay (smallest particles

Question 26

Soil color depends on the _matter that make up the soil

Answer 26

minerals and organic

Question 27

is a measure of how acidic or basic the soil i

Answer 27

Soil pH

Question 28

describes the spaces between soil particles

Answer 28

Pore space

Question 29

describes how well a soil can support plant growth

Answer 29

Soil fertility

Question 30

are light, warm, dry and tend to be acidic and low in nutrients. Sandy soils are often known as light soils due to their high proportion of sand and little clay (clay weighs more than sand). These soils have quick water drainage and are easy to work with. They are quicker to warm up in spring than clay soils but tend to dry out in summer and suffer from low nutrients that are washed away by rain. The addition of organic matter can help give plants an additional boost of nutrients by improving the nutrient and water holding capacity of the soil

Answer 30

Sandy soil

Question 31

are heavy soils that benefit from high nutrients. Clay soils remain wet and cold in winter and dry out in summer. These soils are made of over 25 percent clay, and because of the spaces found between clay particles, clay soils hold a high amount of water. Because these soils drain slowly and take longer to warm up in summer, combined with drying out and cracking in summer, they can often test gardeners

Answer 31

Clay soils

Question 32

are light and moisture retentive soils with a high fertility rating. As silt soils compromise of medium sized particles they are well drained and hold moisture well. As the particles are fine, they can be easily compacted and are prone to washing away with rain. By adding organic matter, the silt particles can be bound into more stable clumps.

Answer 32

Silt soil

Question 33

are high in organic matter and retain a large amount of moisture. This type of soil is very rarely found in a garden and often imported into a garden to provide an optimum soil base for planting

Answer 33

Peat soil

Question 34

can be either light or heavy but always highly alkaline due to the calcium carbonate or lime within its structure. As these soils are alkaline they will not support the growth of ericaceous plants that require acidic soils to grow. If a chalky soil shows signs of visible white lumps then they can’t be acidified and gardeners should be resigned to only choose plants that prefer an alkaline soil

Answer 34

Chalk soil

Question 35

are a mixture of sand, silt and clay that are combined to avoid the negative effects of each type. These soils are fertile, easy to work with and provide good drainage. Depending on their predominant composition they can be either sandy or clay loam. As the soils are a perfect balance of soil particles, they are considered to be a gardeners best friend, but still benefit from topping up with additional organic matter

Answer 35

Loam soil