Nitrogen is often the limiting nutrient in ecosystems.This is because A) there is very little nitrogen on Earth, compared with other nutrients. B) most nitrogen is in the form of N₂, which organisms cannot use. C) the chemical reactions needed to produce usable nitrogen are difficult. D) nitrogen is quickly removed from ecosystems and stored in rocks and sediments. E) humans turn most available nitrogen into ammonia, which organisms cannot use.

Question

Quizplus · Accepted Answer

Nitrogen is often found in the form of N₂, which organisms cannot use directly. It needs to be converted into a usable form through a process called nitrogen fixation. This is why nitrogen is often the limiting nutrient in ecosystems.

Nitrogen Is Often the Limiting Nutrient in Ecosystems