Introduction to Environmental Geology, 5e (Keller)
Chapter 17 Soils and Environment
17.1 Multiple-Choice Questions
1) Why was Times Beach, Missouri, evacuated in 1983?
A) Soils had eroded so deeply in a large rainstorm that streets were irreparably damaged.
B) Soils had become contaminated with dioxin.
C) Soils had become infertile because of excessive agricultural use.
D) Expansive soils damaged most of the buildings in town.
2) How do engineers define soil?
A) solid Earth material that has been altered by physical, chemical, and biological processes
B) solid Earth material strong enough to support structures
C) solid Earth material that can be removed without blasting
D) solid Earth material that is generally fertile
3) Weathered material that remains in its place of formation is called
A) residual soil
B) transported soil
C) expansive soil
D) horizontal soil
4) Which soil horizon is known as the zone of accumulation?
A) A horizon
B) B horizon
C) C horizon
D) R horizon
5) In what way is color an indicator of soil drainage?
A) Well-drained soils tend to be well aerated and red in color.
B) Poorly drained soils tend to be well oxidized and red in color.
C) Moderately drained soils tend to be green in color.
D) Colors of soils are more reflective of organic matter than of drainage.
6) How do soils become fertile?
A) deep and thorough leaching of parent material to release nutrients
B) mild weathering of parent material and addition of organic matter
C) human manipulation to retain moisture and improve texture
D) intimate interaction with the soil biota
7) Soil taxonomy is a classification system based on
A) the processes that formed different soils
B) physical and chemical properties of the soil profile
C) divisions and subdivisions of soil texture
D) the organic matter content of the B horizon
8) Soil cohesion is enhanced by the presence of
A) gravel and sand particles
B) clay and silt particles
C) subsurface water
D) organic matter
9) What is hydraulic conductivity?
A) the velocity at which water passes through soil
B) the proportion of sand and gravel in a soil
C) the number and sizes of pore spaces in a soil
D) the ability of a porous material to transmit water
10) Shrink-swell potential of a soil is dependent upon
A) the hydraulic conductivity of the soil
B) the proportion of clay in the soil
C) the proportion of fine sand in the soil
D) the chemistry and water content of the soil
11) The principal advantage of the Universal Soil Loss Equation is
A) ease of use and ability to evaluate the potential impact of conservation practices
B) rapid estimation of soil erosion at every location in a site of interest
C) ready estimation of reservoir siltation
D) prediction of the amount of nutrient loading in a stream adjacent a farm field
12) Urbanization influences soil erosion processes primarily because of
A) increased runoff from impermeable surfaces
B) increased soil pollution from street runoff
C) vegetation removal and soil disturbance at construction sites
D) desiccation of soils through draining and pumping of water
13) Off-road vehicle use contributes to soil problems by
A) loosening soil and changing the hydrology of a site
B) polluting soil with vehicle emissions
C) changing the local rainfall characteristics
D) changing the classification of a soil
14) A sharp peak in sediment yield in the Piedmont region around 1960 corresponded with a
period of
A) conversion of land to agriculture
B) extensive off-road vehicle use
C) heavy rainfall
D) rapid urbanization
15) In what ways are soil surveys useful for land-use planning?
A) They provide the basis for rating limitations for specific land uses.
B) They provide maps showing the shrink-swell potential of soils.
C) They provide the basis for determining land valuation.
D) They show where existing soils have been covered by urbanization.
17.2 True/False Questions
1) Soil scientists and engineers view soil in essentially the same way.
2) The A horizon of a soil is typically richer in organic matter than is the B horizon.
3) Soil fertility depends primarily on bedrock type.
4) The unified soil classification system, which is based on soil texture, is particularly useful for
agricultural purposes.
5) Clay soils tend to resist deformation because clays have high cohesion and high intra-grain
friction.
6) Coarse-grained soils tend to have relatively low compressibility, low cohesion, low
erodibility, and high hydraulic conductivity.
7) Expansive soils typically present minor, localized problems.
8) Soil erosion is primarily a major problem only at the site where it occurs.
9) Impact of urbanization on soil erosion is primarily a problem during the construction phase.
10) Agricultural soil erosion affects the amount, but not the fertility, of the soil.
11) Off-road vehicles typically reduce soil erosion by compacting the soil.
12) Soil strength is primarily a function of cohesion, friction, and vegetation.
13) A soil E horizon is an eroded horizon.
14) An argillic soil horizon is enriched in clay moved from the A horizon.
1) ________ is the physical and chemical breakdown of rocks.
2) The ________ horizon of a soil is a zone of intense leaching.
3) An argillic B horizon is enriched in ________ transported from the A horizon.
4) A soil that consists of nearly equal amounts of sand and silt with a lesser amount of clay is
called a(n) ________.
5) ________ is the ability of a soil to resist deformation.
6) Response to vibrations is one aspect of soil ________.
7) Soils with the highest hydraulic conductivity consist of ________.
8) ________ works with the natural topography to reduce soil erosion.
9) ________ is the ability of soil particles to stick together.
10) ________ are aggregates of soil particles that comprise soil structure.
11) Soil ________ refers to the ease with which soil particles can be moved by wind or water.
12) A(n) ________ soil profile has a well-developed B horizon.
13) A soil ________ is a series of soils arranged by age according to their relative profile
development.