Soil
Chemical 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
E- ( eluviated )
Leached of clay , minerals , and organic matter , leaving a concentration of sand and silt particles of quartz or other resistant materials
Nitrification of Ammonium
The use of fertilizers , especially those supplying nitrogen , has often been blamed as a cause of soil acidity .
Clay
Very sticky when wet , and can be molded into any shape and form . When they dry , they are rock hard .
Climate
affecting the rate of weathering and organic decomposition
Harvest of High Yielding Crops
its effect on soil acidity development because crops absorb the lime - like elements , as cations , for their nutrition .
Parent material
minerals forming the basis of soil
Pedogenesis
process of soil formation as regulated by the effects of place , environment , and history .
Base
substance that releases hydroxyl ions ( OH- )
Acid
substance that tends to release hydrogen ions ( H + )
Chalky
Alkaline with a pH of about 7.5 . Not acidic and often stony with chalk or limestone bedrock .
Soil Chemistry
Branch of soil science that deals with the chemical composition , chemical properties , and chemical reactions of soils .
Biological Weathering
Breakdown of rocks by living things .
Physical Weathering
Breakdown of rocks from the result of a mechanical action .
Living organisms
-influencing soil formation
R- ( bedrock )
A mass of rock such as granite , basalt , quartzite , limestone or sandstone that forms the parent material for some soils
Peaty
Acidic and as a result , does not support decomposition very well .
Widespread Pollution
Covers extensive areas and has several causes the reasons for which are difficult to identify .
Organic Matter Decay
Decaying organic matter produces H + which is responsible for acidity .
Soil Profile
Dig down deep into any soil , and you'll see that it is made of layers , or horizons ( O , A , E , B , C , R ) .
Acidic Parent Material
Due to differences chemical composition of _______ soils will become acidic after different lengths of time .
pedosphere
Earth's body of soil
Rainfall and Learching
Excessive rainfall is an effective agent for removing basic cations over a long time period .
Silty Soils
Finer , smoother in texture and holds water better than sandy soils .
Sandy Soils
Free draining , with the largest , but fine and hard particles . It has a gritty feel . It does not bind very well . Very low in nutrients .
Soil Formation
Made up mainly of mineral particles , organic materials , air , water and living organisms .
Soil pH
Measure of acidity or alkalinity of a soil .
Soil
Mixture of organic matter , minerals , gases , liquids , and organisms that together support life .
Loamy
Mixture of sand , clay and silt particles and has the ability to retain water .
A - ( topsoil )
Mostly minerals from parent material with organic matter incorporated . A good material for plants and other organisms to live .
O- ( humus or organic )
Mostly organic matter such as decomposing leaves . Thin in some soils , thick in others , and not present at all in others .
Specific Pollution
Occurring in small areas the reasons for which can be easily identified .
B - ( subsoil )
Rich in minerals that leached from the A or E horizons and accumulated here .
25%
Soil is made of about __ % air.
45%
Soil is made of about __ % minerals.
5%
Soil is made of about __ % organic matter.
25%
Soil is made of about __ % water.
Weathering of rocks
Soil is the thin layer of material covering the earth's surface and is formed from the ?
neutral
Soils with a pH of 7 are ?
alkaline or " sweet "
Soils with pH values above 7 are?
acid or " sour "
Soils with pH values below 7 are ?
Environmental Soil Chemistry
Study of chemical reactions between soils and environmentally important plant nutrients , radionuclides , metals , metalloids , and organic chemicals .
C- ( parent material )
The deposit at Earth's surface from which the soil developed .
Clay
The particles that make up ______ are the finest and they bind very well
Topography
grade of slope affecting drainage , erosion and deposition
Time
influencing soil properties
Soil Acidity
involves intensity and quantity aspects . The intensity aspect is universally characterized by the measurements of H + ion activity , expressed as pH .