Tag: soil-nature

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Questions Related to soil-nature

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

Which of the following layer of soil is called as zone of leaching?

  1. $A _0$

  2. $A _{00}$

  3. $A _2$

  4. $A _1$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Leaching is the process by which soluble nutrients are lost from the soil. The A horizon of the soil is the surface layer that consists largely of minerals. The A$ _2$ horizon of this layer shows the maximum leaching. 

So, the correct option is 'A$ _2$'.

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

Which of the following layer of the soil contains more humus?

  1. Top soil

  2. Subsoil

  3. Bedrock

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Top soil contains detritus micro-organisms  that decompose dead plant and animals and add to the organic content of the soil. The decomposed organic matter is called humus.

So, the correct answer is 'top soil'

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

.......... affect the soil profile and bring changes in soil structure.

  1. Vegetation

  2. Animals

  3. Climatic factors

  4. Fertilizers
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

  • Climate affects soil formation because it determines the amount of water that is available for processes such as the weathering of minerals, the transportation of minerals and the release of elements. Climate also influences the temperature of the soil, which determines the rate of chemical weathering.
  • Temperature and rainfall are the two main climatic factors responsible for soil formation. 
  • Hence, Climatic factors affect soil profile and bring changes in soil structure.
So, the correct answer is 'Climatic factors'.

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

Which of the following is not a characteristic of humus?

  1. It is rich in organic matter such as lignin and cellulose

  2. It is colloidal in nature and serves as a reservoir of nutrients

  3. It is highly resistant to microbial action and undergoes slow decomposition

  4. It is further degraded by the process of humification
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Humus is dark brown amorphous gummy substance formed by partial decomposition of plant and animal matter. It constitutes the organic component of soil and is rich in lignin and cellulose. Humus is formed from organic remains through the activity of decomposer microorganism. The process of formation of humus from raw organic remains is called humification. Humus is quite resistant to microbial action. It is a reservoir of nutrients and is helpful in the maintenance of soil moisture as well as aeration. It is colloidal in nature. Nutrients are released slowly as the humus is decomposed slowly. Humus is further degraded by some microbes and release of inorganic nutrients occur by the process of mineralization.

So, the correct answer is 'It is further degraded by the process of humification'.

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

Which of the following statements will not hold true if a plant is grown in only sand (S), only clay (C) and only humus (H)?

  1. Water availability to the roots will be more in (C) and (H) as compared to (S).

  2. Ability of roots to penetrate (S) and (H) will be low as compared to (C).

  3. Nutrient availability to roots will be less in (S) as compared to (C) and (H).

  4. Oxygen availability to roots will be low in (C) as compared to (S) and (H).
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

All statements are true except the ability of roots to penetrate in sand and hummus are low as compared to clay.

So, the correct option is 'Ability of roots to penetrate (S) and (H) will be low as compared to (C).'.

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

In addition to the rock particles, the soil contains

  1. Air and water

  2. Water and plants

  3. Minerals, organic matter, air and water

  4. Water, air and plants
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  • Soil composition refers to the nutrients and various other substances present in the soil. 
  • The basic components of soil are minerals, organic matter, water, and air. The typical soil consists of approximately 45% mineral, 5% organic matter, 20-30% water, and 20-30% air.
  • Hence In addition to the rock particles, the soil contains Minerals, organic matter, air, and water.
  • So, the correct answer is 'Minerals, organic matter, air, and water'.
Multiple choice evs mud and stones soil - formation and profile soil-nature soil profile

The process of mineralisation by microorganisms helps in the release of

  1. Inorganic nutrients from humus

  2. Both organic and inorganic nutrients from detritus

  3. Organic nutrients from humus

  4. Inorganic nutrients from detritus and formation of humus
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Mineralization is the release of inorganic substances, both non-mineral(e.g., CO2, H2O) and mineral(e.g., Ca2+, Mg2+, K+, NH+4) from organic matter. The process is slow because of trapping of these nutrients in humus and their immobilization in decomposers/detritivores. It prevents their washing out or leaching. Nutrients immobilized in decomposer microbes and detritivores are again exposed to humification and mineralization after the death of these organisms.

So, the correct answer is 'Inorganic nutrients from humus'.

Multiple choice biology natural resources - air, water and land soil - formation and profile soil-nature soil profile

Deep black soil is considered to be highly productive due to high proportion of

  1. Silt and earthworm

  2. Clay and humus

  3. Gravel and $Ca^{++}$

  4. Sand and Zn
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Deep black soil (often called Regur or Black Cotton soil) is highly productive because it is rich in clay, which retains moisture, and humus, which provides essential nutrients for plant growth.