Tag: mud and stones

Questions Related to mud and stones

Column I represent the size of the soil particles and Column II
represents type of solid components. Which of the following is
correct match for the Column I and Column II.

Column I Column II
A. 0.2 to 2.00mm (i) Slit
B. Less than 0.002 mm (ii) Clay
C. 0.02 to 0.2 mm (iii) Coarse and particle
D. 0.002 to 0.02 mm (iv) Fine sand particle



  1. (A) - (ii), (B) - (iii), (C) - (iv), (D) - (i)

  2. (A) - (iv), (B) - (i), (C) - (iii) , (D) - (ii)

  3. (A) - (iii) , (B) - (ii) , (C)-(iv), (D) - (i)

  4. None of the above


Correct Option: C
Explanation:

The texture of soil is determined by the proportions of particles of different sizes. Coarse sand particles are of 0.2 to 2.00 mm in size; 0.02 to 0.2 mm particles constitute fine sand; 0.002 to 0.02 particles represent silt and particles smaller than 0.002 mm are called clay.




Major constituent of soil is

  1. Organic matter

  2. Inorganic matter

  3. Soil air

  4. Soil water


Correct Option: B

O-horizon is a

  1. Top soil

  2. Sub-soil

  3. Organic layer

  4. Solum


Correct Option: C

Humus is good for plant growth because ________________.

  1. It makes the soil porous

  2. It increases water holding and aeration of soil

  3. It improves physical condition of soil

  4. All of the above


Correct Option: C

$A _0$ layer is rich in

  1. Litter

  2. Minerals

  3. Leachates

  4. Humus


Correct Option: D

The Precambrian red rock indicates the ________________.

  1. Presence of the free oxygen

  2. Absence of free oxygen

  3. Presence of hydrogen

  4. Presence of water


Correct Option: A

The geological age of a rock is determined by.

  1. The fossil flora and fauna

  2. Chemical composition of the rocks

  3. Radiometric dating

  4. Spectroscopic data


Correct Option: A

Humification results in the formation of ............. substance.

  1. Colloidal and Basic

  2. Acidic and Dark colored

  3. Amorphous and Light colored

  4. Light coloured colloidal


Correct Option: B
Explanation:

  • Humification is a process in which organic material decomposes and breaks down. It results in the formation of humus. Humus is a dark-coloured, amorphous and acidic substance. 
  • It occurs in soils and peats. It improves the quality of soil by providing nutrient substances like nitrogen.

Thus, the correct answer is 'Acidic, Dark coloured.'

'X' is an organic substance obtained from the decomposition of plant or animals wastes which provides lots of humus to the soil. Identify the incorrect statements regarding decomposition.

  1. It makes the soil porous

  2. It reduces the water holding capacity of the soil

  3. it increase the number of friendly microbes

  4. It improves the texture of the soil


Correct Option: D
Explanation:

Humus is the dark, organic material formed in the soil when plant and animal matter decays.
It is important as it retains-
1)  Moisture content in the soil.

2) Loosens the soil which allows better aeration and drainage.
3) It encourages the increase of soil organisms which help make nutrients available to plants. 
4) It makes the soil more porous.
5) High humus content increases water holding capacity of the soil.
So, the correct answer is 'It improves the texture of the soil'.

When a small amount of garden soil is put into a glass jar containing water, stirred and allowed to stand for two hours, the layers from top to bottom would be

  1. Debris, water, sand and clay

  2. Humus, water, clay and sand

  3. Debris, clay, gravel and sand

  4. Humus, clay, gravel and sand


Correct Option: B
Explanation:

Soil is comprised of air spaces and organic matter, but mostly mineral particles. There are three kinds of soil minerals, sand, silt and clay. The relative percentage of each of these particles in the soil determines its texture. Sand has the largest soil particles (0.4- to 0.01-inch diameter) and the largest pores between particles. Silt soil particle size is between clay and sand (0.01- to 0.0001-inch diameter). The characteristics of silty soil are similar to those of clay, but are moderated by its larger particle size. Clay soil has the smallest soil particles (less than 0.0001-inch diameter) and the least amount of water and air spaces between particles. Humus is dark, organic material that forms in soil when plant and animal matter decays. The thick brown or black substance that remains after most of the organic litter has decomposed is called as humus. Hence, humus settles at the topmost and sand the lowermost since, its size is maximum.