Question

In an area, a single banyan tree overshadows 200 parthenium grass. Which of the following is a more meaningful measure of population density?
A. Detritus per cent
B. Standing crop present
C. Total Number per unit area
D. Standing state percent

Answer 1

Ecologists used different terms and definitions to define the population density or ecosystem productivity in terms of pyramid number, the pyramid of biomass, the pyramid of energy and productivity of ecosystems like primary productivity and secondary productivity.

Complete answer:
In a given statement that an area a single banyan tree overshadows 200 parthenium grass, to measure the population density to compare both in terms of standing crop present or either in biomass per cent cover.

In the case of standing crops: The total dried biomass of the living organism or plant present in a given environment is the measure. This thing includes both natural and agricultural ecosystems.

In the case of the pyramid of biomass: The amount of biomass or organic matter present both fresh and dried weight, present in per unit area of different trophic level, is more real than the pyramid of number.

The detritus is the dead organic material present on the ground of the ecosystem which is going to be recycled by the detritus feeder.

Hence, the correct answer is option (A).

Additional information:
Total number per unit are- it represents the total number of individuals of given species living in per unit area in an ecosystem, which is not good to measure the productivity of the ecosystem.

Standing state per cent- it is defined as the amount of inorganic material present in an ecosystem, that represents the non-living matter which circulates in both living and nonliving components of the ecosystem.

Note: Apart from this, there is another measurement method which is the best representation method of ecosystem productivity, it is the pyramid of energy which determines the amount of energy trapped per unit of time in different trophic levels of the food chain.