An integrative theoretical concept—combining scientific approaches from soil science and slope hydrology—is given as a framework to study the influence of depth functions of geochemical concentrations for trace elements, dissolved organic carbon and stable isotopes in the soil pore water of stratified soils on the chemical composition of the hillslope runoff. Combining investigations at the point and hillslope scale opens the opportunity to identify sources of subsurface runoff components using geochemical depth functions as proxies.