DISSOLVED ORGANIC MATTER (DOM): ROLES IN AQUATIC SYSTEMS AND BIOGEOCHEMICAL PROCESSES

Dissolved organic matter (DOM) is a complex mixture of organic molecules derived from biological production, decomposition, and terrestrial inputs in aquatic environments. DOM plays central roles in carbon cycling, nutrient dynamics, and water quality by influencing microbial activity, light penetration, and pollutant transport. Its composition and reactivity vary widely across ecosystems, shaped by sources, physical conditions, and biotic interactions. This article reviews the sources, composition, and ecological significance of DOM, and discusses its role in ecosystem functioning and global biogeochemical cycles. Understanding DOM dynamics is vital for predicting ecosystem responses to environmental change.