Learning Objectives

22.2.1 Describe why decomposition is a critical process in the supply of nutrients in ecosystems.

22.2.2 Evaluate the biological and physical factors that influence rates of decomposition.

22.2.3 Explain how microbial processes may alter the chemical forms of nutrients and make them either more or less available to plants.

Once they have entered an ecosystem, nutrients are subjected to further modifications as a result of uptake by organisms and chemical reactions that alter their form and influence their movement and retention within the ecosystem. Foremost among these transformations is the decomposition of organic matter, which releases nutrients back into the ecosystem.