Question

The rate of formation of new organic matter by deer in a forest ecosystem is called
A. Primary productivity
B. Secondary productivity
C. Standing crop
D. Net primary productivity

Answer 1

Hint:Forest ecosystem is an ecosystem consisting of all the trees, herbs, shrubs, animals, insects, and all the natural habitat that makes it a forest.
Productivity means the rate of generation of biomass in an ecosystem.
Deer are consumers in a forest ecosystem.

Complete answer:
Primary productivity is the rate of formation of new organic matter by producers ie. Plants and other photosynthetic organisms.
Secondary productivity is the rate of formation of new organic matter by consumers. For eg. Protists, fungi, bacteria, Deer, cow, goat, horse, etc.
A standing crop is the total amount of dried biomass of living organisms at a trophic level. It represents the above-ground biomass. It may differ throughout the year.
Primary productivity is of two types-
a) Gross primary productivity: It refers to the total rate of photosynthesis and the organic matter used up in respiration which depends on chlorophyll content.
b) Net primary production is the difference between gross primary production and respiration by organisms in an ecosystem. NPP = GPP-R.

So, the correct answer is B. Secondary productivity

Note: Various environmental factors affect productivity in an ecosystem such as temperature, humidity, nutrition, biotic activities such as predator and parasite relation, grazing, etc, human and nature conflicts, etc.
The amount of primary productivity depends on photosynthetic capacity, and it differs according to climatic conditions both in temperate and tropical regions.