Geochemistry-Utrecht University: Geochemical research at Utrecht University emphasizes the study of processes taking place in environments near the Earth's surface, in particular, soils, sediments, aquifers, estuaries, and the ocean. These environments are characterized by the presence of water and are linked to one another via the hydrological cycle. In addition to being a transport agent, solvent and chemical reactant, water is indispensable for life. The biogeochemical functioning of Earth surface environments is increasingly affected by human activity. The environmental changes due to mankind occur at the local, regional and global scale. An important task of geochemical research is to characterize these changes and to predict the responses of natural systems to anthropogenic perturbations. The study of past environmental changes provides important constraints on these predictions. Hence, geochemists at Utrecht investigate both modern and ancient environments.