Previous year MCQs

Environment & Ecology UPPSC 2024 GS-I
Question

Which of the following is the correct sequence of phases of Biotic succession?

Answer & Solution

Answer: (Detailed Solution Below)

Option D: Migration - Ecesis - Reaction- Stabilisat

Detailed Solution:

The correct answer is “Migration - Ecesis - Reaction- Stabilisat”.

Biotic succession refers to the process of change in the species composition of an ecosystem over time. It occurs in several phases:

Migration: This is the first phase where species move into a newly formed or disturbed habitat. This could involve the movement of seeds, spores, or individual organisms from surrounding areas.

Ecesis: This is the phase where species establish themselves in the new environment. It involves the germination of seeds, growth, and survival of species in the new habitat.

Reaction: This phase refers to the modification of the environment by the established organisms, which may make it more suitable for other species. As the community develops, species interactions and environmental changes occur (e.g., changes in soil quality, moisture, etc.).

Stabilisation: In the final phase, the community reaches a state of equilibrium or climax, where the species composition stabilizes. This is called the climax community, which is relatively stable and persists for a long time unless disturbed.

Similar Questions:

Which of the following is not correctly matched ?
  1. A) Cartagena Protocol - Biosafety
  2. B) Stockholmes Convention - Persistent organic pollutant
  3. C) Montreal Protocol - Ozone Layer
  4. D) Kyoto Protocol - Save Water
Which one of the following agriculture practices is eco friendly?
  1. A) Cultivation of high yielding varieties
  2. B) Growing plants in glass houses
  3. C) Shifting cultivation
  4. D) Organic farming
The"Agenda—21" of RioSummit,1992 is related to-
  1. A) Sustainable development
  2. B) Polluter—Pays principle
  3. C) Preservation of ozone layer
  4. D) Environmental education
The environment modified by human activities is called:
  1. A) Natural environment
  2. B) Anthropogenic environment
  3. C) Urban environment
  4. D) Modern environment
Given below are two statements, one is labelled as Assertion (A) and other as Reason (R) :

Assertion (A) : Various components of an ecosystem are not interdependent,
Reason (R) : Human activities have an impact on the environment.
  1. A) Both (A) and (R) are true and (R) is correct explanation of (A)
  2. B) Both (A) and (R) are true, but (R) is not correct explanation of (A)
  3. C) (A) is true, but (R) is false
  4. D) (A) is false, but (R) is true
Rajiv Gandhi Wildlife Conservation Award is given to:
  1. A) Educational and Research Institutions
  2. B) Forest and wildlife officers
  3. C) Wildlife conservationists
  4. D) All the above
Which of the following is a correct statement?
  1. A) Energy flow in the biospheric ecosystem is unidirectional.
  2. B) Energy flow in the biospheric ecosystem is cyclic.
  3. C) Relative loss of energy in natural ecosystem decreases with increasing trophic levels.
  4. D) Species at progressively higher tropic levels appear to be less efficient in using available energy.
Endangered species are listed in:
  1. A) Dead Stock Book
  2. B) Red Data Book
  3. C) Live Stock Book
  4. D) None of the above
Which one of the following is not correctly matched?
  1. A) Article 153 — Office of the Governor
  2. B) Article 154 — Executive Authority of the Governor
  3. C) Article 155 — Removal of the Governor
  4. D) Article 156 — Term of the Governor
Trophic levels are formed by-
  1. A) Organisms linked in food chain
  2. B) Plants only
  3. C) Animals only
  4. D) Carnivorous animals
Consider the following statements with reference to the Workers and Peasants Party:

1. The Workers and Peasants Party was formed in 1927 and was given the form of an All India Organisation.
2. The objective of this party was to work within the Congress so that it could be made a more revolution inclined party and an organisation of the common people.

Which of the above statements is/are correct?
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  2. B) Neither 1 nor 2
  3. C) Only 1
  4. D) Only2
Which of the following energy sources produces NO atmospheric pollution?
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  2. B) Solar energy
  3. C) Petroleum energy
  4. D) Coal energy