WorksheetsSoil Properties MCQ Quiz
Total questions: 25
Worksheet time: 13mins
The study of soil as a natural entity, focusing on origin, classification, and description, is called:
Pedology
Edaphology
Geology
Soil Science
Which branch of soil science is concerned mainly with plant growth?
Pedology
Edaphology
Pedogenesis
Geomorphology
Soil is considered a three-phase system consisting of:
Solids, gases, nutrients
Solids, liquids, gases
Minerals, organics, nutrients
Rocks, water, air
What percentage of mineral matter generally composes agricultural soil?
25%
45%
5%
20%
Organic matter in soil primarily originates from:
Rocks and minerals
Plants and animals
Gases in the atmosphere
Parent material only
Which soil component usually has higher CO₂ content compared to the atmosphere?
Soil water
Soil air
Soil solids
Soil colloids
Which best describes soil pore spaces?
Occupied only by air
Occupied only by water
Occupied by air and water interchangeably
Always filled with gases
A soil with 25% water, 25% air, and 50% solids is considered:
Ideal soil
Poorly drained
Compact soil
Organic-rich soil
A soil scientist studying soil classification and mapping is best called:
Edaphologist
Pedologist
Petrologist
Hydrologist
Which soil component is responsible for carrying nutrients in solution form?
Soil solids
Soil air
Soil water
Soil colloids
The gaseous component of soil is primarily made up of:
O₂ only
N₂, O₂, CO₂, and traces of others
CO₂ only
CH₄ and CO₂
Which statement is TRUE about soil solids?
Only composed of mineral matter
Only composed of organic matter
Composed of mineral and organic matter
Not essential in soil formation
The mineral matter in soil originates from:
Decomposed plant and animal remains
Weathering of rocks and minerals
Microbial activity
Gaseous fixation
Which soil component acts as a buffer for rapid changes in pH?
Soil air
Soil water
Organic matter
Sand particles
What is the function of soil organic matter?
Improves soil structure and nutrient availability
Decreases microbial activity
Increases bulk density
Reduces water retention
Which soil phase has the least volume in an ideal agricultural soil?
Mineral matter
Organic matter
Air
Water
Soil is considered a "natural body" because:
It is composed entirely of minerals
It is static and unchanging
It results from interaction of parent material, climate, organisms, topography, and time
It is not influenced by the environment
A soil sample has 50% solid, 30% water, and 20% air. Which statement is MOST accurate?
Soil has high porosity and balanced composition
Soil is waterlogged and poorly aerated
Soil has poor fertility
Soil is ideal for plant growth
Which soil function directly supports crop growth?
Storage of heat energy
Medium for plant anchorage and water supply
Storage of gases for the atmosphere
Sink for waste disposal only
Soil air differs from atmospheric air mainly in its:
Higher nitrogen and oxygen levels
Higher carbon dioxide content
Lower CO₂ content
Lack of oxygen entirely
The relative proportion of sand, silt, and clay in soil is known as:
Soil structure
Soil texture
Soil consistence
Soil fertility
Which is NOT part of soil texture determination?
Feel method
Pipette method
Hydrometer method
Soil color method
The smallest soil separate under USDA classification is:
Silt
Clay
Sand
Gravel
Which soil textural class is considered "ideal" for most crops?
Sandy loam
Loam
Clay
Silty clay
A soil has 40% clay, 30% silt, and 30% sand. Its textural class is:
Sandy loam
Clay loam
Loam
Silty clay loam
