Subsurface flow paths in a chronosequence of calcareous soils: impact of soil age and rainfall intensities on preferential flow occurrence

Abstract. Soil hydrologic processes play an important role in the hydro-pedo-geomorphological feedback cycle of landscape evolution. properties and subsurface flow paths both change over time, but due to a lack observations, water are often not properly represented soil evolution models. We investigated across chronosequence calcareous glacier forefield at Griessfirn Swiss Alps. Young soils developed from parent material usually have high pH value, which likely affects vegetation development pedogenesis thus paths. chose four glacial moraines different ages (110, 160, 4 900, 13 500 years) conducted sprinkling experiments with dye tracer Brilliant Blue on three plots each moraine. Each plot was divided into equal subplots, dyed applied irrigation intensities (20, 40, 60 mm h−1) amount 40 mm. Subsequent excavation profiles enabled tracing A types increasing moraine age observed rather homogeneous matrix 110 160 years heterogeneous finger-shaped 900 years. However, proportion preferential is necessarily directly related such as texture, layering, organic matter content, characteristics root length density biomass. Irrigation intensity had effect number two old moraines. also found that this evolved differently compared previous study siliceous material, emphasizes importance for path Our provides rare systematic dataset observations vertical soils, useful improve their representation context modeling.