Nutrient Cycles and Ecosystem Stoichiometry

Abstract

Nutrients have been discussed throughout this book in terms of limiting factors for producers, consumers, and decomposers, as electron donors for microbial decomposers, and in a number of other roles. It is clear, then, that nutrients are inextricably linked to almost all other ecological processes. In this chapter we first look at the transformations, exchanges, and general dynamic of three nutrients: phosphorus, nitrogen, and sulfur. The dyanmics of these three elements illustrate how nutrients interact with sediments and water, and the great significance of oxidation state and the interactions with organisms. Then we examine the stoichiometry by which nutrient cycles are coupled to transformations of organic matter in ecosystems.