Soil

Soil?

• It is “the bridge of life and the inanimate world.

• It is referred to as an interface – a common boundary where different parts of a system interact among

the different parts of the Earth System

Soil?

• It is dynamic and sensitive to almost every aspect of its

surroundings.

• It covers most land surfaces.

1.Where did soil started?

How is soil formed?

Soil is formed from weathering of rocks, weathering of minerals, and decomposition of organic materials. Through time, soil is born because of this so-called weathering

process.

•Soil is a combination of mineral, organic matter, water, air.

25%

25%

45%

5%

Air

Water

Mineral Material

Organic Matter

•It is the product of the complex interplay of several factors:

1. Parent Material

-Source of the weathered mineral from which soils develop.

2. Time

-Important component of any geological process, and soil formation is no exception.

-Rule: The longer the soil has been forming, the thicker it becomes and the less it resembles the parent material.

3. Climate-most influential control of soil formation-A hot, wet climate may produce a thick

layer of chemically weathered soil in the same amount of time that a cold, dry climate produces a thin mantle of mechanically weathered debris

4. Plants and animals-Microorganisms including fungi, bacteria,

and a single-celled protozoa, play an active role in the decay of plant and animal remains. The end product is humus, a material that no longer resembles the plants and animals from which it is formed.

Trivia: Did you know that:

The moon has no soil? All lunar terrains are mantled with a soil-like layer of debris called LUNAR REGOLITH (from bombardment by meteorites)

With few exceptions, Earth’s land surface is covered by regolith (rhegos = blanket, lithos = stone)

Types of Soil

Sandy SoilParticle size: 0.05 to 2mm

Defining Factors:

Large particlesDry and gritty to touch

Easily drains waterLess water retention

Warm and airyEven when wet, easily crumbles

through the fingersLacks essential nutrients

Ideal for crops like:Watermelons, Peanuts, and

Peaches

Ideal for plants like:Tulips, Cistus, and Hibiscus

Clay SoilParticle size: less than 0.002mm

Defining Factors:

Fine particlesSmooth when drySticky when wet

Retains waterDrains poorly

Less spaces to let air passRich in nutrientsCool and dense

Ideal for crops like:Leafy vegetables, Peas, Tomatoes, and Peppers

Ideal for plants like:Roses, Heleniums, Asters, and

Chaenomeles

Silty SoilParticle size: 0.002 to 0.05mm

Defining Factors:

Tiny particlesSlippery when wetNot grainy or rocky

Extremely fertileRetains water

Easily transported by wind and water

Good for agriculture purposesEasily compacted

Ideal for crops like:All vegetables and fruits

Ideal for plants like:Yellow Iris, Milkweed, and Red

Chokeberry

• Loam is soil composed of sand, silt, and clay in relatively even proportions (about 40%-40%-20% concentration respectively). 

• These proportions can vary to a degree however, and result in different types of loam soils: sandy loam, silty loam, clay loam, sandy clay loam, silty clay loam, and loam

• Loam soils generally contain more nutrients, moisture and humus than sandy soils

• They have better drainage and infiltration of water and air than silty soils

• They are easier to till than clay soils.

•The different types of loam soils each have slightly different characteristics, with some draining liquids more efficiently than others.

• It is considered ideal for gardening and agricultural uses because it retains nutrients well and retains water while still allowing excess water to drain away

• Loam is found in a majority of successful farms in regions around the world known for their fertile land

• Loam soil feels soft and crumbly and is easy to work over a wide range of moisture conditions.

http://www.youtube.com/watch?v=uS7zfeK4OTQ

Want to learn more?

Guess It Know #1

What is a system for classifying soils?

SOIL TAXONOMY

Soil Horizons

•Consists largely of organic material

•Upper part: plant-litter such as loose leaves, organic debris, that are still recognizable

•Has teeming microscopic life including bacteria, fungi, algae, and insects

•Largely mineral matter yet biological activity is high and humus is generally present- about 30% in some instances

TOPSOIL

• An impermeable and very compact layer from the formation of clay accumulation

“TRUE SOIL”

• SUBSOIL

•Layer that is characterized by altered parent material

•Below: unweathered parent material

R Horizon

•Weathered bedrock

Testing Soil pH

Using Red Cabbage

1. Take a head of red cabbage and finely chop it using a knife or food processor. The solution created from the cabbage juice will change color depending on the pH of what it comes in contact with.

2. Heat distilled water until boiling. Use pure distilled water will give an accurate pH test result.

3. Add the chopped red cabbage to the boiling distilled water. Allow it to soak for about 10 minutes and then drain the solid pieces out, leaving a violet hued juice. This juice should have a neutral pH of 7.

4. Test the cabbage juice. Pour a small amount into two separate cups, and add vinegar to one cup and baking soda to the other. Vinegar is acidic, and shoukd turn the solution hot pink. The baking soda solution is alkaline and will turn blue or green.

5. Test your soil. Pour a few inches of the cabbage juice into a clean cup and add one to two spoonfuls of soil. Wait 30 minutes and check the color of the solution.

•Purple or violet is a pH near 7, neutral.

•Pink means the soil is acidic with a pH between 1 and 7. The more acidic the soil is, the brighter the pink will be.

•Blue or green is a pH between 8 and 14, alkaline. The brighter the green or blue juice is, the more alkaline it is.

2. How can you determine the age of soil?

The age of the soil can be determined by looking at the horizonation of soil horizon. Upon that you can determine the extent of soil development

Age of soil can be classified as:

Young-the newly developed-can be Horizon O, A, and C-can also be Horizon A,C

Newly Developed (Mature)-has complete horizon-can be Horizon A, B, C, and R

Weathered-highly weathered soil-high in iron oxide-has:

=very thin Horizon A

=very thick Horizon B

(about 5 m)Color : yellowish-brownOr reddish-brown

3. When is it most effective to take soil tests?

Soil testing is to determine soil fertility. It is most effective to take soil tests before plant preparation like plowing, before planting. In that, you can analyze the soil and know how much fertilizer you need to apply to grow specific kinds of plants

Human or Natural Activities with Bad Effects On Soil

1. Sealing- cementation of soils or other construction soils

2. Compaction- the soil id forced closer together resulting to reduce its porosity which is caused by traffic

3. Landslide-soil is eroded, scattered and some places loose too much soil

4. Contamination-mixing of harmful substances reducing the soil’s nourishment

Human or Natural Activities with Bad Effects On Soil

5. Acid Deposition-acids contaminate soil when laboratories or

hospitals throw hazardous materials and acid substances

6. Land vegetation and Degredation-overusing of soil that’s why there is losing of its

nutrients, or fertilizers are not healthy for soil

7. Organic Matter Decline (Intensive Farming)-too much use of artificial fertilizers and other

chemicals or by intensive farming

8. Productivity/ Biodiversity Loss-plant uses too much nitrogen from soil is

consecutively planted which cause loss of nutrient.

Guess It Know #2:It is the process where in soil erosion, the

nutrient-layer of soil is removed which becomes desert-like and unable to support

life.

DESERTIFICATION

Erosion-transport of soil sediments across the

landscape

http://www.youtube.com/watch?v=Hy_PqKsv9mY

Fill in the blanks about the following processes in soil erosion:

1.________________ requires breaking of bonds that holds particle together to the source.

2.________________ is the lifting of particles by the agent/ agents of erosion.

3.________________ is when the process of erosion stops when the particles fall out of the transporting medium and settle on a surface.

Entrainment Deposition Detachment

Human Activities with Good Effects on Soil

1.Strip cropping and contour plowing-can reduce soil erosion as much as 50% gently

sloping lands

2. Windbreaks-blocks the wind and traps eroding soil, rows of

trees planted along edges of fields

3. Terracing-slowdown runoff and catch eroding soil

4. Conservation plowing-leaves the dead stalks and weeds from the

previous years that holds the topsoil in place

Want to learn more?

http://www.youtube.com/watch?annotation_id=annotation_387737&feature=iv&src_vid=Hy_PqKsv9mY&v=7pC7jnJ0OIk

Sources:• Earth Science by Tarbuck and Lutgens

•Phoenix Publishing House: Exploring Life through Science Series

• Soil Expert: Dr. Vigilia Armendi

• Wikipedia

• Wikihow.com

“What we plant in the soil of contemplation, we shall reap in the harvest of action” Meister Eckhart quotes (German Writer and Theologian. 1260-1328)

“Gardening is about enjoying the smell of things growing in the soil, getting dirty without feeling guilty, and generally taking the time to soak up a little peace and serenity.” Lindley Karstens quotes

“The Nation that destroys its soil destroys itself” Franklin D. Roosevelt quotes (American 32nd US President (1933-45), cousin of Theodore Roosevelt, 26th US president. 1882-1945)