Soil geomorphology and landscape evolution
Soils form on almost any location of the landscape; thus, landscape evolution is strongly related to soil development. For example, soil chronosequences are one of the excellent usage of soil geomorphology to better understand landscape evolution through the ability of correlating between terraces, etc. Another example is the study of soil development to gain insight on hillslope properties and processes, such as hillslope convexity. Our group study both of these aspects.
Most mechanistic models of landscape evolution neglect dust addition to soils. We highlight the potential importance of dust and chemical weathering in soil production formulations and hillslope evolution models.
In collaboration with Itai Haviv (BGU) and Josh Roering (U. of Oregon).
Left: Characteristic morphology of loess mantled hills in Northern Negev, note the prominent hillslope convexity (Ben-Asher et al., 2019). Right: A modified soil mass balance formulation along with a hillslope element including soil influx and outflux (qs), soil production from mechanical weathering of bedrock (Pr), dust deposition rate (Pd) and a chemical depletion fraction (CDF) (Ben-Asher et al., 2021)
Publications:
Ben-Asher, M., Haviv, I., Crouvi, O., Roering, J.J., and Matmon, A. (2021). The convexity of carbonate hilltops: 36Cl constraints on denudation and chemical weathering rates and implications for hillslope curvature. Geological Society of America Bulletin, doi: https://doi.org/10.1130/B35658.1.
Ben-Asher, M., Haviv, I., Roering, J.J., and Crouvi, O. (2019). The potential influence of dust flux and chemical weathering on hillslope morphology: convex soil-mantled carbonate hillslopes in the Eastern Mediterranean. Geomorphology, 341, 203-215. https://doi.org/10.1016/j.geomorph.2019.05.021.
Ben‐Asher, M., Haviv, I., Roering, J. J., and Crouvi, O. (2017). The influence of climate and microclimate (aspect) on soil creep efficiency: Cinder cone morphology and evolution along the eastern Mediterranean Golan Heights. Earth Surf. Process. Landforms, 42: 2649– 2662. https://doi.org/10.1002/esp.4214.
Crouvi, O., Pelletier, J.D., and Rasmussen, C. (2013). Predicting the thickness and aeolian fraction of soils in upland watersheds of the Mojave Desert. Geoderma, 195-196C, 94-110. https://doi.org/10.1016/j.geoderma.2012.11.015.
Water divides are dynamic features that may shift over time in response to regional changes in climate or tectonics. Understanding the interaction between the dynamics of the divide and climate/tectonic changes requires an evaluation of the divide dynamics, e.g. its rate of movement and style of migration. The determination of the divide dynamics is a challenging task, as we normally have only a static snapshot of the present drainage network. We study soil chronosequences in the proximity of reorganized channels and estimate their relative and absolute ages.
In collaboration with Liran Goren (BGU) and Eitan Shelef (U. of Pittsburgh).
Water divide at Nahal Botem, near Mt. Berech, southern Negev.
Publications:
Harel, E., Goren, L., Crouvi, O., Ginat, H., and Shelef, E. (2022). Drainage reorganization induces deviations in the scaling between valley width and drainage area. Earth Surf. Dynam. 10, 875–894, https://doi.org/10.5194/esurf-10-875-2022.