Agriculture and Environment: UPSC Previous Year Questions (Environment and Ecology)
3 previous year UPSC Prelims questions on Agriculture and Environment (Environment and Ecology). Choose an option to see the answer and explanation.
Explanations state facts as of the year each question was asked; words like “recently” refer to that year.
Showing 1–3 of 3 questions
UPSC 2018Environment and Ecology · Agriculture and Environment
Q1. Which of the following statements best describes "carbon fertilization"?
Explanation
Carbon fertilisation is the artificial enrichment of the atmosphere of greenhouses with carbon dioxide, an essential nutrient for plants and vegetables. It also goes by the name of "Carbon Dioxide Fertilization." It can be used to grow nearly any form of vegetable (asparagus, celery, lettuce, tomatoes, aubergines, etc.), greenhouse fruit (strawberries), and ornamental plants, and is especially suited for cold climates.
Option (a) is correct: Carbon fertilisation results in an increase in the instantaneous rate of photosynthesis in C3 plants; and increases the transpiration efficiency of the leaf (C3 and C4 plants). During high concentration of carbon dioxide, plants maintain narrow openings of leaf surface which protects them from water loss. Faster plant growth enhances food production and allows for the sequestration of more carbon dioxide. Plants distribute a greater proportion of photosynthate to roots under high concentrations of atmospheric carbon dioxide. The reproductive biomass growth, as well as vegetative biomass growth, is usually increased by elevated carbon dioxide.
Additional insight:
The term that describes "increased temperature of Earth due to increased concentration of carbon dioxide in the atmosphere" is Global Warming. Ocean acidification: It refers to the ongoing decrease in the pH (and thus increasing acidity) of Earth’s oceans due to the absorption of excess carbon dioxide from the atmosphere. The term that describes adaptation of all living beings on Earth to the climate change brought about by the increased concentration of carbon dioxide in the atmosphere is Climate Adaptation.
UPSC 2018Environment and Ecology · Agriculture and Environment
Q2. With reference to agricultural soils, consider the following statements: 1. A high content of organic matter in soil drastically reduces its water holding capacity. 2. Soil does not play any role in the sulphur cycle. 3. Irrigation over a period of time can contribute to the salinization of some agricultural lands. Which of the statements given above is/are correct?
Explanation
Statement 1 is incorrect: Soil water holding capacity is the amount of water that a given soil can hold for crop use. Soil texture and organic matter are the key components that determine soil water holding capacity. Organic matter influences the physical conditions of a soil in several ways.
Statement 2 is incorrect: Sulphur is one of three nutrients that are cycled between the soil, plant matter and the atmosphere. The sulphur cycle describes the movement of sulphur through the atmosphere, mineral and organic forms, and through living things.
Statement 3 is correct: Salinization is a major problem associated with irrigation, because deposits of salts build up in the soil and can reach levels that are harmful to crops.
Exam tip:
S1 and S2 contain extreme phrases like "Drastically reduces" and "any role", hence more probable to be false, instead, S3 contains "some" hence plausible to be true. "Some" = possibility logic, not absolute. If even one species of organism does something, the statement is likely correct.
UPSC 2018Environment and Ecology · Agriculture and Environment
Q3. With reference to the circumstances in Indian agriculture, the concept of "Conservation Agriculture" assumes significance. Which of the following fall under the Conservation Agriculture? 1. Avoiding the monoculture practices 2. Adopting minimum tillage 3. Avoiding the cultivation of plantation crops 4. Using crop residues to cover soil surface 5. Adopting spatial and temporal crop sequencing/crop rotations Select the correct answer using the code given below:
Explanation
Conservation Agriculture (CA) is a farming system that promotes minimum soil disturbance (i.e. no tillage), maintenance of a permanent soil cover, and diversification of plant species. It enhances biodiversity and natural biological processes above and below the ground surface, which contribute to increased water and nutrient use efficiency and to improved and sustained crop production. According to FAO’s website there are three principles of Conservation of Agriculture:
1. Minimum mechanical soil disturbance: It refers to low disturbance no-tillage and direct seeding. The disturbed area must be less than 15 cm wide or less than 25% of the cropped area (whichever is lower).
2. Permanent soil organic cover: Three categories are distinguished: 30-60%, >60-90% and >90% ground cover, measured immediately after the direct seeding operation. An area with less than 30% cover is not considered as CA.
3. Species diversification: Rotation/association should involve at least 3 different crop species. The rotation of crops is not only necessary to offer a diverse "diet" to the soil micro organisms, but as they root at different soil depths, they are capable of exploring different soil layers for nutrients.
Answer key for these questions
Q
UPSC year
Correct answer
1
2018
(a) Increased plant growth due to increased concentration of carbon dioxide in the atmosphere
2
2018
(b) 3 only
3
2018
(c) 2, 4 and 5
Frequently asked questions
How many previous year UPSC questions are there on Agriculture and Environment?
This page covers 3 previous year UPSC Prelims GS Paper-I questions on Agriculture and Environment (Environment and Ecology), asked from 2011 to 2022. Each has the correct answer and an explanation.
How should I use previous year UPSC questions for Prelims?
Attempt each question first, then open the answer and read the explanation for every option. Repeat by chapter, and track which statements UPSC reuses across years. Previous year questions show the exam pattern and difficulty level.
Which years are covered for Agriculture and Environment?
Questions on Agriculture and Environment (Environment and Ecology) are available for 9 years, from 2011 to 2022. Use the Year filter to practise a single paper.
