Environmental Studies · Biology

Soil Science and Fertilizers

1,537 Questions

Soil science focuses on soil formation, classification, and fertility management using fertilizers and organic amendments. Agricultural and environmental science exams heavily feature questions on biofertilizers, mycorrhiza, and phytoremediation. Practice these questions to build a strong understanding of soil nutrient cycles.

Phytoremediation techniquesOrganic soil amendmentsBiofertilizers and mycorrhizaNitrous oxide emissionsIn-situ soil remediationGreen manuring effects

Soil Science and Fertilizers Questions

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

Build up of organic material in soil is under which of the following conditions to

  1. $< 10^oC$ temperature, Absence of oxygen.

  2. Warm temperature, Humid environment
  3. Aerobic conditions, $>25^oC$ temperature

  4. Nitrogen rich detritus, optimum moisture
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Presence of oxygen is necessary for the growth of a microorganism in the organic matter. Under anaerobic conditions most of fungi and actinomycetes growth suppressed only a few bacteria grow in anaerobic organic decomposition. The rate of temperature for maximum growth of the microorganism is 30° to 40°'. The adequate moisture is required for the proper decomposition of organic matter. The rate of decomposition of organic matter is maximum in the neutral soils than the acidic soil. C: N  ratio has a great influence on the decomposition. Narrow C: N ratio of soil and organic water is required for rapid and better decomposition of organic matter.

So, the correct answer is ' Aerobic conditions, > 25°C temperature '


Multiple choice evs modern agriculture agricultural practices in india different types of farming and agriculture various agricultural practices

In which of the following methods the nutrients are supplied through drip irrigation?

  1. Precision farming

  2. Composite farming

  3. Polyhouse farming

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

Drip irrigation also called micro irrigation system is the best for watering plants in a polyhouse. In drip irrigation system, water under high pressure is forced through nozzles arranged on a supporting stand at about 1 feet height. This enables watering at the base level of the plants.This watering system ensures that water does not fall on the leaves or flowers as it leads to disease and scorching problems.

Multiple choice evs modern agriculture agricultural practices in india different types of farming and agriculture various agricultural practices

Which type of farming produces fertilizers? 

  1. Net house farming

  2. Rooftop gardening

  3. Polyhouse farming

  4. Precision farming
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
A Shade net house is a structure made from Hot dip galvanized Steel Pipe with quick couplings and enclosed by Agro nets or Anti Insect net to allow required sunlight, moisture and air to pass through the gaps. The plants that can be grown are:
1)Tomato
2)Seedless cucumber
3)Lettuce
This type of farming even produces fertilizers.
So, the correct answer is 'Net house farming'.
Multiple choice zoology ecosystem : structure and function biogeochemical cycles - sedimentary biogeochemical cycle nitrogen and phosphorus cycles

In phosphorus, cycle phosphorus enters an ecosystem, during which of the following processes?

  1. Weathering

  2. Respiration

  3. Photosynthesis

  4. Nitrification

  5. Condensation
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
A. Weathering is the breakdown of rocks into smaller particles by the action of various environmental factors like wind, water, sunlight etc.
B. Respiration is the process by which living organisms derive energy by the oxidation of various complex organic substances.
C. Photosynthesis is the process by which green plants capture solar energy and convert it into light energy.
D. Nitrification is the conversion of ammonia into nitrates and is performed in two steps, nitrite formation and nitrate formation.
E. Condensation is the process by which gas changes into liquid drops.
Since rocks are made up of phosphorus and contain phosphates, their weathering will cause dissolution of phosphates in the soil and thus, phosphorus enters the ecosystem.
So, the correct answer is 'Weathering'.
Multiple choice zoology ecosystem : structure and function biogeochemical cycles - sedimentary biogeochemical cycle nitrogen and phosphorus cycles

In which of the following cycles does the reservoir of the
nutrient exist in material from

  1. Carbon cycle

  2. Phosphorous cycle

  3. Nitrogen cycle

  4. Water cycle
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The phosphorus cycle is a sedimentary cycle, meaning its primary reservoir is in the Earth's crust (rocks and sediments) rather than the atmosphere.

Multiple choice zoology ecosystem : structure and function biogeochemical cycles - sedimentary biogeochemical cycle nitrogen and phosphorus cycles

Some of the nutrient cycles are labelled as below.
Sulphur cycle (A), phosphorus cycle (B), carbon cycle (C) and nitrogen cycle (D). Of these, the sedimentary cycle is represented by

  1. (A) only

  2. (B) only

  3. (C) only

  4. (A) and (B) only

  5. (C) and (D) only
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The sedimentary cycle is one of the  biogeochemical cycles that forms an important factor for the growth and development of a living organism. For the sedimentary cycle, the major reservoir is the lithosphere which releases the  elements through weathering. The mineral elements required by living organisms are obtained  from inorganic sources either from salts dissolved in water or from rocks. The sedimentary cycle is represented  by phosphorous, sulphur and iodine cycles.
Sulphur cycle is the cycle which allows the circulation of sulphur from the source to the various living organism and back to the natural resources in form of salts of sulphur.

Phosphorous cycle is the cycle which allows the circulation of phosphorous from the source to the various living organism and back to the natural resources in form of salts of phosphorous.

Multiple choice zoology ecosystem : structure and function biogeochemical cycles - sedimentary biogeochemical cycle nitrogen and phosphorus cycles

In which of the following cycles, does the reservoir of the nutrient exist in material from?

  1. Carbon cycle

  2. Phosphorous cycle

  3. Nitrogen cycle

  4. Water cycle
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • The term biogeochemical cycle is used for the exchange or circulation of biogenetic nutrients between living and nonliving components of the biosphere.
  • The nutrient cycle can be a gaseous cycle in which the materials involved in circulation between living and nonliving components are gases or vapors, e.g., carbon, hydrogen, oxygen.
  • In sedimentary cycles of matter; the materials involved in circulation between biotic and abiotic components of the biosphere are non-gaseous e.g., phosphorous, calcium, magnesium.
  • The reservoir of phosphorous is phosphates present in rocks.

    Thus, the correct answer is option B.
Multiple choice zoology ecosystem : structure and function biogeochemical cycles - sedimentary biogeochemical cycle nitrogen and phosphorus cycles

In the phosphorus cycle, phosphate becomes available by weathering of rocks first to _____________.

  1. Consumers

  2. Producers

  3. Decomposers

  4. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
In the phosphorus cycle, weathering makes phosphate available to the soil from where plants or producers get them first.
So, the correct answer is 'Producers'
Multiple choice zoology ecosystem : structure and function biogeochemical cycles - sedimentary biogeochemical cycle nitrogen and phosphorus cycles

Out of nutrient cycles of sulphur (a) phosphorus (b) carbon (c) and nitrogen (d), which one is sedimentary?

  1. a only

  2. b only

  3. c only

  4. a and b only

  5. c and d only
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Biochemical cycle is also called as biogeochemical cycle or nutrient cycle. Biochemical cycle with gaseous phase includes various cycles like carbon cycle, nitrogen cycle, oxygen cycle. The nitrogen, carbon and oxygen are found in the gaseous form in the atmosphere. Calcium cycle, sodium cycle, phosphorous cycle, iron cycle, magnesium cycle, sulfur cycle are sedimentary cycles.

Thus, the correct answer is 'a and b only.'

Multiple choice zoology ecosystem : structure and function biogeochemical cycles - sedimentary biogeochemical cycle nitrogen and phosphorus cycles

In the phosphorus cycle, weathering makes phophate available first to 

  1. Decomposers

  2. Consumers

  3. Producers

  4. All of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The natural reservoir of phosphorus is rock, which contains phosphorus in the form of phosphates. When rocks are weathered, minute amounts of these phosphates is mixed in soil and are absorbed by the roots of the plants. Herbivores and other animals obtain this element from plants. 

So, the correct answer is 'Producers'

Multiple choice zoology ecosystem : structure and function biogeochemical cycles - sedimentary biogeochemical cycle nitrogen and phosphorus cycles

The excreta rich in phosphorus would be called as _________.

  1. Organic excreta

  2. Inorganic excreta

  3. Guano deposits

  4. Both B and C
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Marine birds plays a unique role in phosphorus cycle. These birds eat marine fish, which is rich in phosphorus . Their excreta are called a guano deposits.

Multiple choice zoology ecosystem : structure and function biogeochemical cycles - sedimentary biogeochemical cycle nitrogen and phosphorus cycles

Weathering of rocks makes phosphorus available to first

  1. Producers

  2. Decomposers

  3. Consumers

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

There are 4 layers of Earth, namely lithosphere (land), hydrosphere (water), biosphere (living), and atmosphere (air). Lithosphere of Earth includes the crust, sedimentary rocks and the uppermost mantle. It is reservoir of phosphorus. Hence, weathering of rocks makes phosphorus available to first producers.

Thus, the correct answer is 'Producers.'

Multiple choice biology transport in plants transport of food, water and minerals theories of translocation transport in the phloem of plants

The theory of transfer of ions from soil to root without passing into solution was given by

  1. Jenny.

  2. Oversheet.

  3. Donnan.

  4. Both A and B.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

According to the theory of ions put forth by Jenny and Overstreet, ions are transferred from soil to root or vice versa without passing into solution. The ions are electrostatically adsorbed to the surface of root cells and are held tightly. These ions oscillate within a small volume of space called oscillation volume. When the oscillation volume of two ions of same charge overlap one ion is exchanged for the other. This is called contact exchange. Thus the transfer of ions from soil to root takes place without passing into solution. Thus the correct answer is option D.