Environmental Studies · Biology

Soil Science and Fertilizers

1,509 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 botany adaptation plant adaptation adaptation in plants plant habitat importance and classification of angiosperms aquatic plant adaptations pollination through water life in water

Nitrates, phosphates and sulphates are plants

  1. Disease

  2. Pollutants

  3. Nutrients

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

Nitrates, phosphates, and sulphates are essential inorganic compounds that plants absorb from the soil to synthesize proteins and other vital molecules, thus acting as nutrients.

Multiple choice civics the nature of the indian economy part 1 three phases of indian agriculture cash crops of india agricultural nature of indian economy plantation of crops

What is the full form of chemical fertilizer, N.P.K.?

  1. Nitrogen, Phosphorus and Calcium

  2. Nitric acid, Phosphorus and Calcium

  3. Nitrogen Phosphorus and Potassium

  4. Nitric acid, Phosphorus and Potassium
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

NPK stands for "nitrogen, phosphorus, and potassium," the three nutrients that compose complete fertilizers. ... Also implied is a percentage symbol after each number because each of the three numbers represents the percentage of that nutrient in the makeup of the fertilizer.

Multiple choice evs a seeds tells a farmer's story manure manures and fertilisers water absorption organ

What is manure?

  1. It is a natural material obtained by decaying plant and animal waste.

  2. It is a synthetic material prepared in laboratory.

  3. It is a semi synthetic material.

  4. It can be both natural and synthetic.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Manure is a natural material, obtained by decaying plant and animal waste, that can be applied to the soil to enhance its fertility. Manure usually consist of faeces and urine of domestic livestock, with or without accompanying litter such as straw, hay, or bedding. The most common sources of manure are cows, horses, sheep.

So, the correct answer is 'It is a natural material obtained by decaying plant and animal waste '.

Multiple choice evs a seeds tells a farmer's story manure manures and fertilisers water absorption organ

The organic manure is considered better than fertilisers because

  1. It can be prepared in the factories.

  2. It is less rich in plant nutrient.

  3. It improves the texture of the soil.

  4. It decreases the water holding capacity of the soil.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The organic manure contains a high amount of organic matter which increases the capability of the soil to hold the water. They are prepared by the decomposition of the organic matter by the microbes. They are highly rich in the plant nutrients. They also help to improve the quality and texture of the soil. The gaseous exchange takes place easily in this soil which allows the germination and growth of the plants properly. 

Thus, the correct answer is option C. 

Multiple choice evs a seeds tells a farmer's story manure manures and fertilisers water absorption organ

Which of the following can replenish nutrients in the soil?

  1. Fertilizer

  2. Manure

  3. Compost

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

There are different methods by which nutrients in the soil can be replenished. Fertilizers and manures contain plant nutrients such as nitrogen, phosphorus, potassium. Fertilizer can be added to the soil. It helps in replenishing exhausted soils with rich sources of organic nutrients. Manure is environment friendly and replenishes the soil with organic nutrients. Compost is decomposed organic material. It reintroduces living organisms and nutrients in the soil. It improves soil structure and provides a healthy environment for plant roots. 

Thus, the correct answer is 'All of the above.'

Multiple choice evs a seeds tells a farmer's story manure manures and fertilisers water absorption organ

Bio-fertiliser which makes available phosphorus is?

  1. Azolla

  2. Aulosira

  3. Mycorrhiza

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

Mycorrhizal fungi, which form a symbiosis with the roots of nearly all vascular plants, play a key role in solving the phosphate shortage problem for plants. Mycorrhizal fungi can effectively increase phosphate uptake by converting insoluble phosphates to soluble, available forms.

So, the correct option is 'Mycorrhiza'.

Multiple choice evs a seeds tells a farmer's story manure manures and fertilisers water absorption organ

Biofertilizers are preferred over chemical fertilisers because

  1. They are cheap

  2. They do not cause pollution

  3. They are harmful

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Biofertiliser are preferred over chemical fertilisers because they contain organic materials while fertilisers contain chemical substances that when used in excess become harmful to the consumers. Continuous application of fertilisers to the soil decreases its fertility and also leads to increase in the acidity of the soil. Also the fertiliser runoff from the fields also causes water pollution. Cyanobacteria such as Anabaena and Nostoc also fix atmospheric nitrogen and act as bio-fertilisers especially in paddy fields.
So the correct option is 'They do not cause pollution' .
Multiple choice evs a seeds tells a farmer's story manure manures and fertilisers water absorption organ

Biofertilizers increase the _________ content of the soil.

  1. Nutrient

  2. Humus

  3. Water

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

Biofertilizer is a substance that contains living organisms which is used to increase the fertility of the soil. It improves the growth of plant by increasing the content of the soil and thereby increasing the availability of nutrients to the host plant. Also, it does not allow pathogens to flourish. Various biofertilizers are Rhizobium, Azotobacter, blue green algae (BGA). They live in symbiotic association with the plants and provides nitrogen to the plant. 

Thus, the correct answer is option A.

Multiple choice evs a seeds tells a farmer's story manure manures and fertilisers water absorption organ

Cow dung that is used as a fertilizer can be replaced by 

  1. Insecticides.

  2. Pesticides.

  3. Biofertilizers.

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

Traditionally, cowdung is used as a fertilizer. It provides growing medium for plants. It is nutrient-rich fertilizer. It is either mixed into the soil or used as top dressing. However, methane (greenhouse gas) is emitted from cowdung when it is processed. Hence, it is replaced by biofertilizers. Biofertilizers are substances which contains live organisms and are used to increase fertilizer of the soil. Examples of biofertilizers include rhizobium, azotobacter, azospirillum and blue green algae(BGA).

Thus, the correct answer is option C.

Multiple choice evs a seeds tells a farmer's story manure manures and fertilisers water absorption organ

Which of the following plants are used as green manure in crop field and in sandy soils?

  1. Crotalaria juncea and Alhagi camelorum

  2. Calotropis procera and Phyllanthus niruri

  3. Saccharum munja and Lantana camara

  4. Dichanthium annulatum and Azolla nilotica
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Crotalaria juncea and Alhagi camelorum are used as green manure in crop fields and sandy soils because these plants, when grown, replenish the soil with sufficient nutrients and nitrogen content after its usage by the crop plant.

So, the correct option is 'Crotalaria juncea and Alhagi camelorum'.

Multiple choice evs a seeds tells a farmer's story manure manures and fertilisers water absorption organ

Which of the following can differentiate chemical fertlizers from natural fertilizers?

  1. Chemical fertilizer is soluble but not natural fertilizer.

  2. Natural fertilizer is nutrient specific but not chemical fertilizer.

  3. Chemical fertilisers can affect the pH of the soil while natural fertilisers do not affect the pH of the soil.

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

  • Those fertilizers which get decomposed naturally are known as natural fertilizers whereas those which are human-made are known as chemical fertilizers. 
  • Natural fertilizers include compost, animal waste, dead organisms, etc. Chemical fertilizers include inorganic materials. 
  • Chemical fertilizers are directly available whereas natural fertilizers need to be prepared. Chemical fertilizers contain different chemical so they affect the pH value of soil whereas natural fertilizers don't.

So, the correct option is 'Both A and C'.

Multiple choice zoology living and non living characteristics of life attributes of living organisms signs of life biology : an introduction living world and classification

Which of the following helps in decomposition in soil and increases its nutrient content in the soil?

  1. Fungi

  2. Virus

  3. Protozoa

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

Fungi feed by saprophytic mode of nutrition on dead and decaying plants and animals. In this, the fungi release enzymes on the dead organism and break down complex substances into simpler substances. They absorb the required amount of released nutrients and release the rest in the soil hence increase its nutrient content.

So, the correct answer is 'Fungi'.

Multiple choice chemistry nitrogen and sulfur nitrogen gas component of air - nitrogen nitrogen

$\mathrm{A}$ nitrogenous fertilizers having more nitrogen is :

  1. $(\mathrm{N}\mathrm{H} _{4}) _{2}\mathrm{S}\mathrm{O} _{4}$
  2. $Ca(NO _{3}) _2$
  3. $NH _{2}CONH _{2}$
  4. $NH _4NO _3$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Percentage of $N _2$ in following compounds is calculated by formula 
$(atomic weight of N _2 in compound / Atomic weight  the compound)\times100$
So, percentage of $N _2$ in compounds is given as
In ${(NH _4)} _{2}SO _4$ it is 21%
In $Ca{(NO _3)} _{2}$ it is 17%
In $NH _2CONH _2$ it is 47%
In $NH _4NO _3$ it is 35%.