Phosphorus and Sulphur Cycling in Terrestrial Ecosystems

Abstract

Phosphorus (P) and sulphur (S) are essential elements for all living cells. Among the biomolecules that contain P are nucleic acids (DNA and RNA), phospholipids, sugar phosphates (e.g. glucose-6-phosphate) and molecules with an energy-rich pyrophosphate bond (e.g. ATP), whereas S is contained in two amino acids (cysteine and methionine) and various coenzymes, vitamins and sulpholipids. The forms, amounts, transformation processes and cycling rates of the two elements in terrestrial ecosystems are usually studied either from an agronomic point of view, i.e. from the perspective of imminent deficiencies, since both elements are major plant nutrients and therefore essential to achieve sufficient crop yields, or from an environmental point of view, where a surplus of these elements in ecosystems may lead to eutrophication or even direct toxicity effects in the case of S.