Tag: mud and stones

Questions Related to mud and stones

Clayey soil is found in

evs mud and stones soil types types of soil soil - types, uses and need for conservation

  1. Tamil Nadu

  2. Jharkhand

  3. Odisha

  4. All of the above

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Correct Option: D

Plants growing on sandy soil are

evs mud and stones soil types types of soil soil - types, uses and need for conservation

  1. Lithophytes

  2. Psammophytes

  3. Hydrophytes

  4. Xerophytes

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Correct Option: B
Explanation:
  • Psammophytes are plants that thrive in shifting sands, primarily in deserts. They have a number of adaptations that enable them to exist on wind-blown sands. 
  • Lithophytes are plants that grow on stones and rocks or in their crevices.
  • Hydrophytes are aquatic plants that live in water and are evolutionarily suited to thrive in aquatic environments.
  • Xerophytes are plant species that have adapted to live in dry or desert conditions. They have evolved to bear and survive in extreme and harsh environments.

The weathering of rocks is caused by 

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

  1. Wind, water, and climate

  2. Only wind, and clay

  3. Only wind, and water

  4. Wind, water, and gravel

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Correct Option: A

Soil has five components. The proportions of different components are

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

  1. Mineral Matter-$40\%$, Organic Matter-$10\%$, Soil Moisture -$25\%$, Soil Atmosphere -$25\%$, Soil Organism- Variable

  2. Mineral Matter-$40\%$, Organic Matter-$10\%$, Soil Moisture -$25\%$, Soil Atmosphere - $25\%$, Soil Organism- $10\%$

  3. Mineral Matter-$40\%$, Organic Matter-$10\%$, Soil Moisture -$35\%$, Soil Atmosphere -$25\%$, Soil Organism- $10\%$

  4. Mineral Matter-$30\%$, Organic Matter-$20\%$, Soil Moisture -$25\%$, Soil Atmosphere -$25\%$, Soil Organism- $10\%$

Show answer
Correct Option: A
Explanation:

While a nearly infinite variety of substances may be found in soils, they are categorized into four basic components: minerals, organic matter, air and water. Most introductory soil textbooks describe the ideal soil (ideal for the growth of most plants) as being composed of 45% minerals, 25% water, 25% air, and 5% organic matter. In reality, these percentages of the four components vary tremendously. Soil air and water are found in the pore spaces between the solid soil particles. The ratio of air-filled pore space to water-filled pore space often changes seasonally, weekly, and even daily, depending on water additions through precipitation, throughflow, groundwater discharge, and flooding. The volume of the pore space itself can be altered, one way or the other, by several processes. Organic matter content is usually much lower than 5% . Some wetland soils, however, have considerably more organic matter in them (greater than 50% of the solid portion of the soil in some cases).


Microorganisms are the final basic element of soils, and they are found in the soil in very high numbers but make up much less than 1% of the soil volume. A common estimate is that one thimble full of topsoil may hold more than 20,000 microbial organisms. The largest of the these organisms are earthworms and nematodes and the smallest are bacteria, actinomycetes, algae, and fungi. Microorganisms are the primary decomposers of raw organic matter. Decomposers consume organic matter, water, and air to recycle raw organic matter into humus, which is rich in readily available plant nutrients.

So the correct option is 'Mineral Matter-40%,Organic Matter-10%,Soil Moisture -25%, Soil Atmosphere -$25$%,Soil Organism- Variable'.

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

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

  1. $A _0$

  2. $A _{00}$

  3. $A _2$

  4. $A _1$

Show answer
Correct Option: C
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$'.

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

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

  1. Top soil

  2. Subsoil

  3. Bedrock

  4. None of the above

Show answer
Correct Option: A
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'

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

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

  1. Vegetation

  2. Animals

  3. Climatic factors

  4. Fertilizers

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Correct Option: C
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'.

Which of the following is not a characteristic of humus?

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

  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

Show answer
Correct Option: D
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'.

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)?

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

  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).

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Correct Option: B
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).'.

In addition to the rock particles, the soil contains

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

  1. Air and water

  2. Water and plants

  3. Minerals, organic matter, air and water

  4. Water, air and plants

Show answer
Correct Option: C
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'.