Our understanding of how soils change over time and how this influences ecological, hydrological and geomorphological processes is still elementary. Some soil properties are persistent, but others can change rapidly with significant effects on water quantity and quality. This is particularly true at the hillslope scale, where lateral and vertical transport processes interact over various timescales. Water and vegetation shape the surface and subsurface properties of hillslopes through weathering, soil development, and erosion. These processes, in turn, control water flow paths. The distribution of water also affects the vegetation, while vegetation in turn also affects the flow pathways for water. The multidisciplinary HILLSlope Chronosequence And Process Evolution (HILLSCAPE) DFG project focuses on the vertical and lateral redistribution of water and matter along hillslopes and how this redistribution affects and is affected by soil, vegetation and landscape development. The project uses a chronosequence (4 ages) of highly instrumented plots at a glacier forcefield at the Klausenpass Glacier forcefield in Switzerland. For each age class, the vegetation complexity and functional biodiversity has been mapped (PhD student Geobotany), however, the interaction of there vegetation with the hydrological soil properties is still missing.
For a range of plots at each age class with the different functional biodiversity and vegetation complexity, experiments will be performed to determine the infiltration pathways using Brilliant Blue Dye tracer experiments.
Both projects need to run in parallel with the HILLSCAPE field campaign from July to Sept 2018 (July to Sept 2019 at the Klassenpass site) and in order to interact with the scientist of the project and to use available resources (accommodation etc.). Based on the mapped vegetation characteristics, the sites will be selected together with the Geobotany group and the experiments will be performed individually. Special equipment (e.g. sloping ring infiltrometer) have been developed in advance and additional observations of the soil properties will be taken in the field (soil hydrological mapping, root distribution)
For the field work, a period of roughly 2 month is foreseen at the field site and supporting the HILLSCAPE team may be necessary from time to time. In addition to performing the field experiments under variable weather and field conditions, the students will perform empirical and geo statistical analysis (Topic 1) and empirical and image processing analysis (topic 2).
English or German
Markus Weiler firstname.lastname@example.org, Michael Scherrer-Lorenzen (Geobotany Uni Freiburg), Theresa Blume (GFZ), Ilja van Meerfeld (Uni Zürich)
Weiler, M., & Naef, F. 2003. An experimental tracer study of the role of macropores in infiltration in grassland soils. Hydrological Processes, 17(2), 477-493. Bachmair, S., Weiler, M., Nützmann, G. 2009. Controls of land use and soil structure on water movement: Lessons for pollutant transfer through the unsaturated zone Journal of Hydrology, 369(3-4), 241-252. Ghestem M, RC Sidle, A Stokes. 2011 The influence of plant root systems on subsurface flow: implications for slope stability. BioScience, 61: 869-879. Ghimire CP, et al. 2013. Reforesting severely degraded grassland in the Lesser Himalaya of …. JGR: Earth Surface 118: 2013JF002888.