Which of the following types of soil has minimum water retention capacity?
Correct Answer:
(A)
Alluvial Sand soil
Alluvial sand soil has minimum water retention capacity because soil with limited water holding capacity (i.e., sandy loam) reaches the saturation point much sooner than a soil with a higher water holding capacity (i.e., clay loam).
Ques:
32
The water holding capacity of different types of soils decreases in the order:
Correct Answer:
(A)
Clay > Silt > Sand
The water holding capacity of different types of soils in descending order is - Clay–silt–sand.
Ques:
33
Consider the statements:
Assertion (A): Among various types of soils, clay retains highest amount of water.
Reason (R): Clay has pore spaces of large size.
Select the correct answer using the codes given below:
Codes:
(A) and (R) are true, and (R) is the correct explanation of
(A).
Correct Answer:
(C)
is true, but (R) is false.
Among various types of soil, clay retains the highest amount of water. Sandy soil has pore spaces of large size. Silt has relatively small pore spaces then sandy clayey soil has the highest water retaining capacity because it has least pore spaces.
Ques:
34
Which soil particles are present in loamy soils?
Correct Answer:
(D)
All types of particles
Generally, Loam soil has 40% sand particles, 40% clay particles and 20% silt particles. Thus, option (d) is correct.
Ques:
35
Choose the correct statement out of the four statements given regarding alluvial soil:
Correct Answer:
(B)
Phosphoric acid is found in rich quantity in this soil.
Alluvial Soils: They are the largest group covering about 11 lakh sq. km or about 33.5% of the total area. Alluvial soils have Potash, phosphoric acid and alkalis in sufficient quantity. But the proportion of nitrogen is low. Alluvial soils as a whole are very fertile.
Reh, Thur, Chopan, Kallar, Rakar, Karl etc. are the local names for saline soils.
Ques:
36
Given below are two statements, one is labelled as Assertion (A) and the other as Reason (R).
Assertion (A): Black soils are suitable for cotton cultivation.
Reason (R): They are rich in humus.
Select the correct answer from the code given below:
(A) and (R) are true, and (R) is the correct explanation of
(A).
Correct Answer:
(C)
is true but (R) is false.
'Black Soil' or 'Regur Soil' or 'Black Cotton Soil' are generally clayey, deep and impermeable. They swell and become sticky when wet, and shrink when dried. So, during the dry season these soils develop wide cracks. Thus, there occurs a kind of 'Self-ploughing'. Because of this character the black soil retains the moisture for as very long time, which helps the crops, especially the rainfed ones, to sustain even during the dry season. Due to these characteristics, black soils are suitable for cotton cultivation. This soil lacks in phosphorus, Nitrogen, and humus.
Ques:
37
Which of the following statements is NOT correct?
Correct Answer:
(D)
Black soil is found in the Himalayan region
The Black soil is locally called regur which is good for growing cotton. It is found mainly in the states of Maharashtra, Gujarat, Karnataka and Madhya Pradesh. Due to high clayey content and high iron content, the regur soil responds well to irrigation and retains moisture.
Ques:
38
Lava soils are found in:
Correct Answer:
(C)
Malwa plateau
The black soil of western India is made up of lava. Hence it is also known as Lava soil. The Malwa Plateau comes under this black soil region of Deccan trap.
Ques:
39
Which soil needs little irrigation as it retains soil water?
Correct Answer:
(B)
Black
The black soil has a high moisture retention level. Remarkably "self-ploughed" by loosened particles fallen from the ground into the cracks, the soil retains moisture. The black soil needs little irrigation as it retains soil water. Hence, option (b) is correct.