FINALS SOIL CHEMISTRY

The deposit at Earth's surface from which the soil developed.

C - (parent material)

This factor is related to how soil properties may vary depending on how long the soil has been weathered.

Time

influencing soil properties.

Time

grade of slope affecting drainage, erosion and deposition

Topography

this is the shape, length and grade of a slope affects drainage. The aspect of a slope determines the type of vegetation and indicates the amount of rainfall received. These factors change the way soils form.

Topography

Soil forms continuously, but slowly, from the gradual breakdown of rocks throug ________. _______ can be a physical, chemical or biological process:

Weathering

covers extensive areas and has several causes the reasons for which are difficult to identify. Cases such as these involve the spreading of pollutants by air-ground- water systems and seriously affect human health and the environment

Widespread Pollution

14. Soils with a pH of 7 are neutral. Soils with pH values below 7 are....

acid or "sour"

(wind transported)

aeolian

soils with pH values above 7 are ......

alkaline or "sweet".

The pH level of ________ ____ __ ______ _, and it usually contains a great deal of sodium, calcium and magnesium.

alkaline soil / above 7 ph

(water transported)

alluvial

Transported soils include:

alluvial (water transported) colluvial (gravity transported) aeolian (wind transported) soils.

influencing soil formation

living organisms

Soils with a pH of 7 are

neutral

is divided into 14 divisions or pH units numbered from 1 to 14

pH Scale

minerals forming the basis of soil

parent material

—breakdown of rocks from the result of a mechanical action. Temperature changes, abrasion (when rocks collide with each other) or frost can all cause rocks to break down.

physical weathering

The soils left on steep hills are usually _______

shallower

The accumulation of material through the action of water, wind and gravity also contributes to

soil formation

A pH of 9 is _______ ____ ______ more alkaline than a pH of 8 and a pH of 10 is ___ _____ _____ ___ alkaline than a pH of 9

ten times more

is defined as a substance that tends to release hydrogen ions (H+)

An acid

Rich in minerals that leached (moved down) from the A or E horizons and accumulated here.

B - (subsoil)

act to both create and destroy order within soils.

Biogeochemical processes

is produced when ammonium containing materials are transformed to nitrate in the soil.

Acidity caused Nitrification

Soil alkalinity/Alkaline soil is referred to by some gardeners as.....

"sweet soil."

The major causes for soils to become acidic are listed below:

1. Rainfall and Leaching 2. Acidic Parent Material 3. Organic Matter Decay 4. Harvest of High Yielding Crops 5. Nitrification of Ammonium

Two types of soil pollution:

1. Specific Pollution 2. Widespread Pollution

One teaspoon of healthy soil contains ___ individual bacteria

100 million - 1 billion

a soil with a pH of 10 is ___ times more alkaline than a soil with a pH of 8

100 times

The pH scale is divided into __ divisions

14

Earthworms populations consume _________ of dry matter per acre per year

2 tons

soil is made up of

25%water 45%minerals 5%organic matter 25%air

Mostly minerals from parent material with organic matter incorporated. A good material for plants and other organisms to live.

A - (topsoil)

is defined as a substance that releases hydroxyl ions (OH-)

A base

This is defined a cause in which thedifferences in chemical composition of parent materials, causes the soil to become acidic after different lengths of time

Acidic Parent Material

are alkaline with a pH of about 7.5. It is not acidic and often stony with chalk or limestone bedrock. It is free draining because of its coarse and stony nature. Not the best for crops to grow in as they lack manganese and iron.

Chalky/Chalky Soils

It has very little air spaces. ____ very sticky when wet, and can be molded into any shape and form. When they dry, they are rock hard.

Clay

do not drain very well. Clay is believed to form in places where

Clay soils

is believed to form in places where the rock is in contact with water, air or steam. Example, sediments on sea or lake bottoms may become ____ _____ with time.

Clay/Clay Soild

This factor is described as temperature affecting the rate of weathering and organic decomposition. With a colder and drier climate, these processes can be slow but, with heat and moisture, they are relatively rapid.

Climate

affecting the rate of weathering and organic decomposition

Climate

has its effect on soil acidity development because crops absorb the lime- like elements, as cations, for their nutrition.

Crop Production/Harvesting of crops

Leached of clay, minerals, and organic matter, leaving a concentration of sand and silt particles of quartz or other resistant materials - missing in some soils but often found in older soils and forest soils.

E - (eluviated)

is the study of chemical reactions between soils and environmentally important plant nutrients, radionuclides, metals, metalloids, and organic chemicals.

Environmental soil chemistry

is an effective agent for removing basic cations over a long time period (thousand of years).

Excessive rainfall

contains less basic materials than leaves or stems.

Grains

soils that developed from _______ material are likely to be more acidic than solids developed from calcareous shale or limestone.

Granite

This soil is a mixture of sand, clay and silt particles and has the ability to retain water. It is high in calcium, aeration and ideal for most crops and vegetables. It is the soil all farmers dream of, as it is full of nutrients from decomposed organic material. It is soft and easy to cultivate.

Loamy

It is defined as The use of fertilizers, especially those supplying nitrogen, has often been blamed as a cause of soil acidity.

Nitrification

The more ________ ______ _____ is applied, the more acidic the soil gets.

Nitrification

Mostly organic matter such as decomposing leaves. The _ horizon is thin in some soils, thick in others, and not present at all in others.

O - (humus or organic)

It produces H+ which is responsible for acidity

Organic Matter Decay/Decaying organic matter

Like rainfall, the contribution to acid soil development by _____ _________ is generally very small, and it would only be the accumulated effects of many years that might ever be measured in a field.

Organic Matter Decay/Decaying organic matter

Soil formation is influenced by ________ (such as plants), micro-organisms (such as bacteria or fungi), burrowing insects, animals and humans

Organisms

Most _______ get their nutrients from the soil and they are the main source of food for humans, animals and birds. Therefore, most living things on land depend on soil for their existence.

Pants

Soil minerals form the basis of soil. They are produced from rocks through the processes of weathering and natural erosion. Water, wind, temperature change, gravity, chemical interaction, living organisms and pressure differences all help break down _____ _________.

Parent Materials

The types of ________ ________ and the conditions under which they break down will influence the properties of the soil formed.

Parent Materials

are acidic and as a result, does not support decomposition very well. It is dark in color, rich in organic material, although contains less nutrients than loamy soils. It retains water very well

Peaty/Peaty Soils

is the process of soil formation as regulated by the effects of place, environment, and history.

Pedogenesis

is a very old weathered landscape with many ancient soils.

Queensland (and Australia)

A mass of rock such as granite, basalt, quartzite, limestone or sandstone that forms the parent material for some soils - if the bedrock is close enough to the surface to weather. This is not soil and is located under the C horizon.

R - (bedrock)

It is a cause for soil to become acidic. it may take hundreds of years for new parent material to become acidic under this condition

Rainfall and Leaching/high rainfall.

is most effective in causing soils to become acidic if a lot of water moves through the soil rapidly.

Rainfalls

are free draining, with the largest, but fine and hard particles. It has a gritty feel. It does not bind very well. It is poor in holding water and easily warms up in the spring season.

Sandy soil

are often the first to become more acidic because water percolates rapidly, and sandy soils contain only a small reservoir of bases (buffer capacity) due to low clay and organic matter contents.

Sandy soils

are very low in nutrients, as they are usually washed away. Its degree of aeration depends on the sizes of the particles, which vary a lot in size. It is usually formed from the weathering or disintegration of bedrock such as shale, limestone, granite and quartz.

Sandy soils

When silt is deposited and cemented with time, it form

Silstone

are so small and not easily seen by the eyes. It leaves a bit of residue after you touch them

Silt particles

This kind is finer, smoother in texture and holds water better than sandy soils. It also holds up nutrients and makes it better for crop cultivation

Silty Soils

are heavier than sandy soils, and almost midway between the properties of sandy and clay soils. It is formed when fine sediments (dust, organic matter and debris) are carried by water or ice and deposited.

Silty Soils

It is made up mainly of mineral particles, organic materials, air, water and living organisms—all of which interact slowly yet constantly.

Soil

is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life

Soil

is the thin layer of material covering the earth's surface and is formed from the weathering of rocks.

Soil

These processes can be very slow, taking many tens of thousands of years.

Soil Formation

you'll see that it is made of layers, or horizons (O, A, E, B, C, R). Put the horizons together, and they form a ______

Soil Profile

involves intensity and quantity aspects.

Soil acidity

is referred to by some gardeners as "sweet soil."

Soil alkalinity/Alkaline soil

is discipline embracing all chemical and mineralogical compounds and reactions occurring in soils and soil- forming processes.

Soil chemistry

is the branch of soil science that deals with the chemical composition, chemical properties, and chemical reactions of soils

Soil chemistry

a complex problem that requires governments, institutions, communities and individuals to take joint measures.

Soil degradation

It describes the concentration of hydrogen ions in the soil solution.

Soil ph

accounted for by particular causes, occurring in small areas the reasons for which can be easily identified.Land pollution such as this is normally found in cities, old factory sites, around roadways, illegal dumps and sewage treatment stations

Specific Pollution

High yielding forages, such as ________ or __________, cause soil acidity to develop faster than with other crops.

bermudagrass or alfalfa

—the breakdown of rocks by living things. Burrowing animals help water and air get into rock, and plant roots can grow into cracks in the rock, making it split.

biological weathering

breakdown of rocks through a change in their chemical makeup. This can happen when the minerals within rocks react with water, air or other chemicals.

chemical weathering

(gravity transported)

colluvial

the strength of the acid depends upon the?

degrees of ionization (release of hydrogen ions) of the acid

Phenomena such as ...... are the major causes of current soil degradation.

erosion, loss of organic carbon, increased salt content, compacting, acidification and chemical pollution

The particles that make up clay are the _____ and they _____ very well.

finest and they bind very well

All acids contain...

hydrogen ions

Among the most common causes of soil contamination caused by human activity, highlights....

industry, mining, military activities, waste — which includes technological waste — and wastewater management, farming, stock breeding the building of urban and transport infrastructures.

aspects. The intensity aspect is universally characterized by the measurements of H+ ion activity, expressed as pH.

intensity aspect

Soil is the thin layer of material covering the earth's surface and is formed from the ____________

weathering of rocks.

Earth's body of soil, called the pedosphere, has four important functions:

• as a medium for plant growth • as a means of water storage, supply and purification • as a modifier of Earth's atmosphere • as a habitat for organisms • as a protector fro