Chapter 12 Flashcards
Agricultural operations can cause modifications to the C Horizon
False
Soils in wet tropical regions tend to have high organic matter and distinct profiles
False
Weathered rock can be a source of essential minerals for plants
True
Plants with low C:N ratios decay rapidly
True
Sawdust added to the soil can cause nitrogen deficiency
True
Organic matter has a positive charge
False
Higher earthworm populations are achieved in conventional tillage in comparison to no-till
False
Plants infected with mycorrhizal fungi can absorb phosphorus better than noninflected plants
True
Productive soils are densely packed
False
A plant will extract water at field capacity until it reaches the permanent wilting point
True
Sandy soils darin at a faster rate than clay soils
True
Soils that are fertile and hold nutrients will have a low cation exchange capacity
False
The pH of a soil is important because it influences the availability of plant nutrients
True
Most crops grow well in soils with high salinity
False
Crop yields will increase indefinitely in response to increasing fertilizer
False
Synthetic fertilizers are used to provide organic matter to the soil
False
Geologic erosion occurs at a faster rate than soil formation
False
Erosion can leave behind less fertile subsoils
True
How thick does the soil layer tend to be in agricultural regions? A. 3 to 4 inches B. 4 to 12 inches C. 3 to 4 feet D. 4 to 12 feet
C. 3 to 4 feet
A vertical section through the soil extending from the surface to the unweathered rock is best described as the: A. Crust B. Horizon C. Profile D.Core
C. Profile
The topsoil is also known as the: A. A horizon B. B horizon C. C horizon D. O horizon
A. A horizon
The subsoil is also known as the: A. A horizon B. B horizon C. C horizon D. O horizon
B. B horizon
Which horizon has the highest amount of organic matter? A. A horizon B. B horizon C. C horizon D. O horizon
D. O horizon
Which of the following is one of the most important soils in agriculture production? A. Aridisol B. Mollisol C. Gelisol D. Spodosol
B. Mollisol
Which is the predominant parent material for soils? A. Igneous Rock B. Sedimentary rock C. Soil aggregation D. soil texture
D. Soil texture
The fineness or coarseness of a soil is called: A. Soil field capacity B. Soil structure C. Soil aggregation D. Soil texture
D. Soil Texture
Sand and silt are chemicals composed mostly of: A. Silica B. Potassium C. Aluminum D. Magnesium
A. Silica
Which soil particle contributes most to pant nutrition? A. Sand B. Silt C. Clay D. Silica
C. Clay
The clustering of soil particles into various shapes is called: A. Soils Field capacity B. Soil structure C. Soil Salinity D. Soil Texture
B. Soil Structure
The pH range that most field crops grow best at is: A. 4-5 B. 5-6 C. 6-7 D. 7-8
C. 6-7
Which of the following is an index that rates the soils for intensive agriculture production on a 0 to 100-value scale? A. Crop Agriculture Index B. Crop Productivity Index C. Crop Parameter Index D. Crop Suitability Index
B. Crop Productivity Index
One distinction between organic and inorganic fertilizers is that organic fertilizers contain: A. Carbon B. Nitrogen C. Potassium D. Lime
A. Carbon
Which of the following fertilizer nutrients is NOT obtain for mining? A. Phosphorus B. Nitrogen C. Potassium D. Lime
B. Nitrogen
Limestone is applied to soil to: A. Increase organic matter B. Add potassium C. Add phosphorus D. Increase soil pH
D. Increase soil pH
The biochemically weathered uppermost portion of Earth’s crust is called _______
Parent Material
The layers seen within a soil profile are called ______
Horizons
The number of elements essential for plant growth is _______
17
_________, ___________, and _________ are three essential elements that plants can obtain from the air
Carbon, oxygen and hydrogen
___________ is the portion of the soils that includes animal and plant residues
Organic matter
The soil water that drains through the soils within 48 hours of irrigation or rainfall is called ____________
Gravitational Water
The soil water content after drainage of gravitational water is called __________
Field Capacity
The three soils particles are _______, ________ and ________
Sand, Silt and Clay
The property too having beneficial qualities relating to crop plant growth is soil ________
Tilth
The concentration of hydrogen ions in a soil is the ______
Soil Reaction (pH)
The three terms used to describe soils salinity are ______, ________ and ________
saline, sadoic, and saline-sodic
A material applied to the soil to promote plant growth is called a ________
Fertilizer
Plants that are grown and plower under while green in order to provide organic mater and nutrients to the soils are known as ________
Green Manure
Commercial nitrogen fertilizers are made through the _________ process
Habor-Bosch
Erosion is the accelerated loss of soils through the action of ________ or _______
Wind or Water