Question

Which atom is limiting the primary productivity mostly?

• A. Carbon
• B. Nitrogen
• C. Phosphorus
• D. Ca

Answer 1

The correct option is A Carbon

Primary production provides the organic carbon that supports the metabolism of ecosystems. Primary production is regulated by factors such as light, temperature, herbivores and the supply of water and nutrients. Models of primary production in ecosystems must consider multiple limiting processes. Net primary productivity varies widely among ecosystems from tens to thousands of grams carbon per year. The most important primary production is converted back to CO${}_2$ is through respiration but some residual carbon accumulates in biomass and refractory organic matter. The storage and fate of this unrespired carbon are important in understanding ecosystems as carbon sources and sinks.

So the correct answer is 'Carbon'.