Tracing chemical diversity in dissolved organic matter from freshwaters to marine environments

This dataset provides detailed measurements of the chemical composition and proton-binding properties of dissolved organic matter (DOM) collected along the Ebro River continuum, from its headwaters to the Mediterranean Sea. Samples were collected across different seasons to capture spatial and temporal variability. The dataset includes quantified concentrations of low- and high-affinity DOM binding groups (expressed in mmol·mol C⁻¹), estimates of the organic contribution to total alkalinity (μmol binding groups·L⁻¹), and metadata on sampling locations, environmental conditions, and physicochemical parameters.
The data enable exploration of seasonal shifts and spatial gradients in DOM reactivity, with particular attention to the influence of riverine processes, such as groundwater inputs, terrestrial runoff, and in-river degradation. Researchers can use this dataset to examine DOM's role in micronutrient cycling, carbon transport, and buffer capacity in aquatic systems.