CEPSCI Soil Science and Erosion Fundamentals

Question 1

What are the three types of soil particles, listed from largest to smallest?

Accepted Answer

Sand, silt, clay

Answer

Gravel, sand, silt

Answer

Clay, silt, sand

Answer

Loam, sand, gravel

Question 2

Which soil textural class is generally considered most erodible by water?

Accepted Answer

Silt and fine sand

Answer

Clay

Answer

Gravel and coarse sand

Answer

Organic peat soils

Question 3

What is 'raindrop splash erosion' (interrill erosion)?

Accepted Answer

Erosion caused by the impact of raindrops detaching soil particles and splashing them into suspension

Answer

Erosion caused by concentrated channel flow

Answer

Erosion of stream banks by flowing water

Answer

Wind erosion on a construction site

Question 4

The Universal Soil Loss Equation (USLE) estimates:

Accepted Answer

Average annual soil loss from a field based on rainfall, soil erodibility, slope, cover, and management factors

Answer

The total volume of stormwater runoff from a site

Answer

The depth to groundwater beneath a site

Answer

The cost of erosion damage to downstream properties

Question 5

What is soil compaction, and why is it a concern on construction sites from a stormwater perspective?

Accepted Answer

Compaction reduces soil porosity and infiltration capacity, increasing stormwater runoff volume

Answer

Soil compaction makes soil stronger, which is always beneficial for erosion control

Answer

Compaction improves soil structure and vegetation establishment

Answer

Compaction has no effect on stormwater runoff

Question 6

What is 'rill erosion' and how does it differ from sheet erosion?

Accepted Answer

Sheet erosion removes a uniform thin layer of soil; rill erosion involves concentrated flow that carves small channels into the soil surface

Answer

Rill erosion is wind erosion; sheet erosion is water erosion

Answer

Rill erosion only occurs near streams; sheet erosion occurs everywhere

Answer

They are the same process described by different terms