Question

What is primary productivity? Give brief description of factors that affect primary productivity.

Answer 1

Primary productivity is defined as the amount of energy accumulation in photosynthetic organisms, by the process of photosynthesis, as biomass or organic matter per unit area over a period of time. It varies in different types of ecosystems because of the different factors that influence it like

• Plant species composition and succession: type of species determine rate and type of photosynthetic pathway.
• Photosynthetic activity: greater the activity, higher the primary production.
• Availability of nutrients, sunlight and precipitation: determine photosynthetic activity and hence, govern primary productivity.
• Type of soil and a number of environmental factors also determine primary productivity.
• eg. Primary productivity is greater for a grassland than a desert.