In the deserts dust deposition can be an important input of sediment and nutrients. Dust deposition is a combination of dust eroded in far-away regions and more local erosion sources (Offer and Goossens, 2001). In extreme situations dust storms with dust concentrations up to 3000 mg/m occur (Brenig and Offer, 2001). Macro-topography as hills, valleys and mountains influence dust deposition (Offer and Goossens, 2004). Micro-topography as pebbles and shrubs are likely to influence dust deposition as well, though a research in the Northern Negev Desert did not demonstrate a difference in dust deposition based on micro-topographic, surface cover variation (Shachak and Lovett, 1998).
Case Studies: » Israel
In the current LAPSUS model dust deposition is assumed equal over a whole catchment, though adaptations can be made in future. In the model currently dust deposition is included as a layer of sediment (mm) added to the soil depth and digital elevation model of the studied area. Dust is added per time step.
- soildepth = soildepth + dust deposition
- dem = dem + dust deposition
- Brenig, L. and Offer, Z., 2001. Airborne particles dynamics: towards a theoretical approach. Environmental Modeling & Assessment, 6: 1-5.
- Offer, Z.Y. and Goossens, D., 2001. Airborne particle accumulation and composition at different locations in the northern Negev desert. Zeitschrift fur Geomorphologie, 45(1): 101-120.
- Offer, Z.Y. and Goossens, D., 2004. Thirteen years of aeolian dust dynamics in a desert region (Negev desert, Israel): analysis of horizontal and vertical dust flux, vertical dust distribution and dust grain size. Journal of Arid Environments, 57: 117-140.
- Shachak, M. and Lovett, G.M., 1998. Atmospheric deposition to a desert ecosystem and its implications for management. Ecological Applications, 8(2): 455-463.