JAMB Biology Past Questions & Answers - Page 316

1,576.

The process of soil erosion is usually from

A.

rill → sheet → gully

B.

gully → rill → sheet

C.

sheet → guly → rill

D.

sheet → rill → gully

E.

rill → gully → sheet

Correct answer is D

No explanation has been provided for this answer.

1,577.

Leaching is 

A.

Washing away of humus from the soil surface

B.

reducing of soil aeration by pressure

C.

soil erosion by means other than rainfall

D.

loss of organic matter due to exposure to direct sunlight

E.

washing out chalk and limestone from upper layers of by heavy rains

Correct answer is A

No explanation has been provided for this answer.

1,578.

Denitrifying bacteria in nature liberate gaseous nitrogen directly from 

A.

ammonium salts

B.

soil nitrates

C.

thunderstorms

D.

soil nitrites

E.

plant and animal proteins

Correct answer is B

No explanation has been provided for this answer.

1,579.

If a handful of soil is shaken with water and left to settle, the soil particles will settle from light to heavy particles as follows 

A.

humus, clay, silt, sand, stones

B.

humus, silt, clay, sand, stones

C.

humus, clay,silt, stones, sand

D.

humus, sand, silt, clay, stones

E.

clay, humus, silt, sand, stones

Correct answer is A

No explanation has been provided for this answer.

1,580.

Erosion can be reduced along shape by

A.

ridging across slope

B.

ridging up slope

C.

 ridging down slope

D.

crop rotation

E.

bush fallowing system

Correct answer is A

No explanation has been provided for this answer.