Which of the following statements about primary productivity is incor…

The correct answer is Option (3) → Primary productivity depends on the consumer species inhabiting a particular area.

Primary productivity is the rate at which plants produce biomass by photosynthesis. Since it is the work of the plants, it depends on the plant species of the area, on environmental factors, on the nutrients available and on the photosynthetic capacity of the plants. For this reason it differs from one type of ecosystem to another.

Option (1) Primary productivity depends on a variety of environmental factors. — A correct statement. Primary productivity depends on a variety of environmental factors.

Option (2) Primary productivity depends on the availability of nutrients and the photosynthetic capacity of plants. — A correct statement. The availability of nutrients and the photosynthetic capacity of plants both affect primary productivity.

Option (3) Primary productivity depends on the consumer species inhabiting a particular area. — An incorrect statement. Primary productivity depends on the plant species inhabiting an area, because plants are the producers. Consumers do not carry out primary production.

Option (4) Primary productivity varies in different types of ecosystems. — A correct statement. Because the factors above differ from place to place, primary productivity varies in different types of ecosystems.

NCERT Extract:
Productivity – “… Secondary productivity is defined as the rate of formation of new organic matter by consumers. Primary productivity depends on the plant species inhabiting a particular area. It also depends on a variety of environmental factors, availability of nutrients and photosynthetic capacity of plants. Therefore, it varies in different types of ecosystems.”