Chapter 12- Soil Flashcards
A complex,plant-supporting system made up of disintegrated rock, remains of wastes of organisms, water, gases, nutrients, and microorganisms
Soil
The base geological material in a particular location.
Parent material
The continuous mass of solid rock that makes up earths crust.
Bed rock
Describes the physical and chemical processes that break down rocks and minerals into smaller particles. Often the first process in soil formation
Weathering
What are the six soil horizons and their names
- O Horizon: litter later
- A Horizon: topsoil
- E Horizon: leaching layer
- B Horizon: subsoil
- C Horizon: weathered/parent material
- R Horizon: parent material
What is in the soil horizons
O: mostly organic matter
A: organic matter mixed with minerals
E: minerals and organic matter leach down to B
B: minerals and organic matter accumulate
C: weathered parent material only slightly altered or not at all by soil formation
R: parent material
Which Horizon has the most plant nutrients available?
A horizon (topsoil)
What happens to particle size in organic matter as you move down to the horizons?
As one moves downward through soil a profile, the particle size increases and concentrate of organic matter decreases.
What happens to minerals in soil?
Minerals are transported downward as a result of leaching.
What is leaching?
The process where solid particles suspended or dissolved in a liquid are transported to another location.
A cross-section of all the soil horizons in a specific soil, from surface to bedrock.
Soil profile
Particles less than 0.002 millimeters in diameter
Clay
Particles ranging from 0.002 to 0.05 millimeters in diameter
Silt
A mix between clay, for silt, and sand and is the best for agriculture.
Loam
Particles with diameter of 0.05 or greater
Sand
What are some factors that influence soil formation?
Climate, organisms, landforms, parent material, and time
What are the two main types of weathering?
Physical and chemical wheathering
The drop-off of eroded material at a new location.
Deposition
The state/process of rotting/decay
Decomposition
The organic component of soil, formed by the decomposition of leaves and other plant material by soil microorganisms
Humus
What color is best for soil
A darker color soil
Is a soil more porous if it has larger particles or smaller particles?
Larger because of there would be more space in between the particles
What does a medium clumpiness mean for soil?
Clumpy soil may have a great deal of humus, meaning that the soil is rich in nutrients and can hold water. It is great for agriculture
What is pH and how may it affect plants?
PH is the acidity or alkalinity. Most plants need an average amount. Some need really high amounts but most die with high pH levels
The deterioration of the soil characteristics needed for plant growth or other ecosystem services.
Soil degradation
The process of eroding or being erased by wind, water, or their material agents
Erosion
The planting of different crops in mixed arrangements
Intercropping
When a farmer alternates crops grown in a field
Crop rotation
The planting of crops after a harvest and before planting.
Cover crops
Rows of trees or other plants that are planted along the edges of fields to slow the wind
Shelterbelts
The turning over of soil before planting; A method opposite of this that reduces erosion
Tilling; no till farming
A farming practice used on steep mountains and look like a staircase
Terracing
Plowing sideways across the hillside, perpendicular to the hill’s slope
Contour farming
A consequence of ranching
Overgrazing
Excessive grazing which causes damage to grassland/What can this cause?
Overgrazing can cause massive erosion and plant loss.
Which forestry practice causes the most erosion?
Clear cutting
What is desertification and what are the 8 main things that cause it?
A loss of more than 10% productivity due to: 1.erosion
- soil compaction
- forest removal
- overgrazing
- drought
- salt buildup
- climate change
- depletion of water sources
What is/caused the Dust Bowl and when did it take place?
Farmers destroyed the fields due to too much ranching and agriculture, causing massive dust storms in the 1930s. The dust bowl is what this region is called.
The providing of water other than precipitation to crops.
Irrigation
The buildup of salt and upper soil horizons, caused by too much or carelessly timed irrigation waterlogging crops
Salinization
What are three solutions to salinization?
- Avoid planting crops that require a great deal of water and dry areas
- Irrigate with water that is low in salt content
- Supplying no more water than crops require and close to the roots.
Irrigation that targets water directly at the root
Drip irrigation
Chemicals that kill organisms that attack or compete with plants that we value
Pesticides
Compounds used to kill pests
Chemical pesticides
Battling pests by using organisms that eat or infect them; An example
Biological pest control; and example of this is a wasp laying eggs on a caterpillar that is hurting crops.
A naturally occurring soil bacteria that produces a protein that kills many caterpillars and the larva of some flies and beatles
Bt
Different techniques combined to achieve the most effective long-term test reduction
Integrated pest management or IPM
The process by which male sex cells of a plant fertilizer female sex cells of a plant
Pollination
A syndrome that caused entire hive of honeybees to die or disappear for unknown reasons
Colony collapse disorder
What do N, P, and K stand for; why are the important to plants?
N- nitrogen
P- phosphorus
K- potassium
The more of this there is the more nutrients there is in the soil
