Soil formation (pedogenesis) video clip

What is soil often comprised of?

• Only clay

• Only organic remains

• A mixture of organic remains, clay, and rock particles

• Only rock particles

Which soil order typically develops in tropical and subtropical latitudes?

• Aridisols

• Mollisols

• Entisols

• Oxisols

What causes the breakdown of rocks or parent material over time?

• Chemical weathering

• Human activity

• Mechanical weathering such as frost or rain

• Biological activity

What type of soils form at the mouths of rivers?

• Alluvial soils

• Oxisols

• Mollisols

• Aeolian soils

What determines the chemical composition, properties, and nutrient content of soils?

• The amount of sunlight

• The parent material

• The amount of water

• The type of microorganisms present

Which soils are created from limestone and commonly support grassland environments?

• Andisols

• Mollisols

• Entisols

• Histosols

What influences a soil's ability to retain and drain water?

• The type of crops grown

• The particle size of the soil

• The amount of organic matter

• The color of the soil

How does climate directly affect soil?

• By determining the temperature and water content

• By changing its mineral composition

• By altering its texture

• By determining its color

What is the most important factor determining the nature of a soil over time?

• The type of bedrock beneath it

• The types of plants that grow in it

• The amount of rainfall it receives

• Time

What human activities disturb the soil, altering its chemical makeup?

• Observing the soil

• None of the above

• Clear-cutting forests, planting crops, using fertilizers and pesticides

• Walking on the soil