The trophic level that has a certain mass of living material at a particular time is called as:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → Standing crop
Organisms at each trophic level depend on the level below for their energy. The mass of all the living organisms at one trophic level, at one particular time, is the standing crop. It is measured as biomass (fresh or dry weight) or as the number of organisms in a unit area.
(1) Standing crop — Correct. It is the stock of living material present at a particular time.
(2) Productivity — Incorrect. It is the rate of biomass production per unit area over a period of time, for example g m-2 yr-1. Standing crop is an amount at one moment, and productivity is a rate over time.
(3) Stratification — Incorrect. It is the vertical distribution of different species at different levels of an ecosystem, such as trees in the top layer of a forest and herbs at the bottom.
(4) Respiration loss — Incorrect. It is the part of the organic matter made by plants that they use up in their own respiration. It is not a mass of living material.
Note: A similar question was also asked in CUET (UG) 2023 on 30-05-2023 (Slot 1) and on 25-05-2023 (Slot 3).
NCERT Extract:
Energy Flow – …
