Chapter 12

Question 1

The weathered layer of loose inorganic material overlaying unfragmented rock is

A. clay.

B. separates.

C. horizons.

D. regolith.

E. peds.

Answer 1

D. regolith.

Question 2

The boreal forest in subarctic locations is the typical setting for _________ .

A. erosion

B. gleization

C. podzolization

D. calcification

E. laterization

Answer 2

C. podzolization

Question 3

A soil pH measuring 7 on the standard pH scale is considered

A. very acidic.

B. very alkaline.

C. unsuitable for agriculture.

D. too basic for minerals to form.

E. neutral hence most suitable for majority of plants and microorganisms.

Answer 3

E. neutral hence most suitable for majority of plants and microorganisms.

Question 4

The soil horizon comprising unconsolidated parent material beyond the reach of most roots is ________.

A. A horizon

B. C horizon

C. B horizon

D. O horizon

E. Z horizon

Answer 4

B. C horizon

Question 5

The productive wheat lands of parts of Washington, Oregon, and Idaho are underlain by soils incorporating volcanic ash and classified as _________.

A. andisols

B. mollisols

C. inceptisols

D. ultisols

E. spodosols

Answer 5

A. andisols

Question 6

The soil forming factor which relates to the parent material composition is the _________ forming factor.

A. climatic

B. geologic

C. metamorphic

D. biological

E. topographic

Answer 6

B. geologic

Question 7

Earthworms are important in soil processes due to

A. their length.

B. their ability to consume soil.

C. their excreted casts increasing amounts of nutrients.

D. their slime trails.

E. their ability to enhance biologic decay.

Answer 7

C. their excreted casts increasing amounts of nutrients.

Question 8

Regimes where soil-forming physical-chemical-biological processes occur are called

A. transformation regimes.

B. laterization regimes.

C. latholithic regimes.

D. pedogenic regimes.

E. aridisol regimes.

Answer 8

D. pedogenic regimes.

Question 9

_______ are positively charged particles which are essential for soil fertility and plant growth.

A. Cations

B. Anions

C. Isotopes

D. Ions

E. Colloids

Answer 9

A. Cations

Question 10

When the available soil water has been completely depleted, the _______ point has been reached.

A. nonsaturation

B. evaporation

C. eluviation

D. wilting

E. leaching

Answer 10

D. wilting