Tag: soil - formation and profile

Questions Related to soil - formation and profile

Precious stones, such as gem stones, are products of

evs mud and stones soil - formation and profile soil-nature soil profile

  1. Volcanic rocks

  2. Sedimentary rocks

  3. Metamorphic racks

  4. Igneous rocks

Show answer
Correct Option: D
Explanation:
  • A gemstone, also known as the precious stone, jewel, a gem is a piece of mineral crystal which is cut and polished and it is used to make jewellery or other accessories. Gemstones are formed from igneous rocks. Interlocking crystals grow within intrusive igneous rock and may form gemstones depending on elements present, cooling time and the environment.
  • Hence precious stones, such as gemstones, are products of igneous rocks.
  • So, the correct answer is 'Igneous rocks'.

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



evs mud and stones soil - formation and profile soil-nature soil profile

  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

Show answer
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

evs mud and stones soil - formation and profile soil-nature soil profile

  1. Organic matter

  2. Inorganic matter

  3. Soil air

  4. Soil water

Show answer
Correct Option: B

O-horizon is a

evs mud and stones soil - formation and profile soil-nature soil profile

  1. Top soil

  2. Sub-soil

  3. Organic layer

  4. Solum

Show answer
Correct Option: C

Humus is good for plant growth because ________________.

evs mud and stones soil - formation and profile soil-nature soil profile

  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

Show answer
Correct Option: C

$A _0$ layer is rich in

evs mud and stones soil - formation and profile soil-nature soil profile

  1. Litter

  2. Minerals

  3. Leachates

  4. Humus

Show answer
Correct Option: D

The Precambrian red rock indicates the ________________.

evs mud and stones soil - formation and profile soil-nature soil profile

  1. Presence of the free oxygen

  2. Absence of free oxygen

  3. Presence of hydrogen

  4. Presence of water

Show answer
Correct Option: A

The geological age of a rock is determined by.

evs mud and stones soil - formation and profile soil-nature soil profile

  1. The fossil flora and fauna

  2. Chemical composition of the rocks

  3. Radiometric dating

  4. Spectroscopic data

Show answer
Correct Option: A

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

evs mud and stones soil - formation and profile soil-nature soil profile

  1. Colloidal and Basic

  2. Acidic and Dark colored

  3. Amorphous and Light colored

  4. Light coloured colloidal

Show answer
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.

evs mud and stones soil - formation and profile soil-nature soil profile

  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

Show answer
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'.