Key Concepts

CONCEPT 22.1 Nutrients enter ecosystems through the chemical breakdown of minerals in rocks or through fixation of atmospheric gases.

CONCEPT 22.2 Chemical and biological transformations in ecosystems alter the chemical form and supply of nutrients.

CONCEPT 22.3 Nutrients cycle repeatedly through the components of ecosystems.

CONCEPT 22.4 Freshwater and marine nutrient cycles occur in a moving medium and are linked to terrestrial ecosystems.