Dry aeolian dust accumulation in rocky deserts: �a medium-term field experiment based on short-term wind tunnel simulations

Abstract

The spatial pattern of medium-term (a few months) dry aeolian dust accumulation in rocky deserts is predicted using shortterm deposition and erosion experiments in a wind tunnel. The predictions are tested in a field experiment set up in the northern Negev Desert of Israel. The results show that superimposing wind tunnel deposition and erosion maps usually leads to correct predictions of medium-term dust accumulation. The predictions are somewhat less confident near the inflection lines of windward hillslopes, where small-scale irregularities in the local topography make it difficult to locate the exact position of the areas of little accumulation. Elsewhere in the topography predictions are good, and the method works satisfactorily.Highest accumulation occurs on concave windward slopes and, to a lesser extent, on slopes parallel to the wind. Little accumulation occurs on the convex windward slopes and in dust separation bubbles. The smallest accumulation rates are observed immediately upwind of the top of pronounced hills and on leeslopes.The rate of dry dust accumulation measured during the field experiment varied from 17 to 93 g m À2 a À1 , depending on the topographic position of the accumulation plots. For most plots, it was of the order of 30±60 g m À2 a À1 .

Spatial distribution of dust deposition within a small drainage basin: Implications for loess deposits in the Negev Desert

“…Similar wind tunnel experiments were also reported by other scholars (Zufall et al, 1999;Brenig & Offer, 2001;Parker & Kinnersley, 2004). As for the Negev, field measurements, reported by Goossens (2000) and Goossens & Offer (1990 and Offer & Goossens (1995), were interpreted to support their wind tunnel experiments.…”

“…Subsequently, the data herein differ from those of Goossens & Offer (, ), Goossens () and Offer & Goossens (), regarding the preferential deposition of dust at the windward (principally at the concave slope section) aspect. The differences in field data may stem from the use of wet traps (Goossens & Offer, ; Offer & Goossens, ), which tend to trap all particles crossing the actual surface area occupied by the trap.…”

“…Previous measurements included dust (Goossens & Offer, 1990;Offer & Goossens, 1995;Goossens, 2000) and measurements of the depth of the colluvial sediments and the aeolian aprons, i.e. loess accumulation (Goossens & Offer, 2005).…”

Contemporary geochemical composition and flux of aeolian dust to the San Juan Mountains, Colorado, United States

“…Our estimates of dust fluxes to the SJM were based on observations from a single location with a small spatial sampling area (0.5 m 2 ), which may complicates efforts to scale up deposition fluxes to regional estimates. There is clear evidence that landscape position can influences deposition rates [ Goossens , 2000]. Vegetation can also influence dust deposition [ Hoffmann et al , 2008; Tegen et al , 2002a] and interception of dust by sub‐alpine forests may increase dust accumulation rates below tree line.…”

The effect of rain, wind-driven rain and wind on particle transport under controlled laboratory conditions

“…Butzen et al, 2015;Iserloh et al, 2013bIserloh et al, , 2013cIserloh et al, , 2012Keesstra et al, 2016;Montenegro et al, 2013;Peter et al, 2014;Prosdocimi et al, 2016;Ries et al, 2013Ries et al, , 2009Rodrigo Comino et al, 2016;Vermang et al, 2015;Wirtz et al, 2012) and wind (e.g. Fister and Ries, 2009;Funk and Engel, 2015;Goossens, 2000;McKenna Neuman et al, 2005;Youssef et al, 2012;Zhang et al, 2014;Zobeck et al, 2013), few focused on wind-driven rain (Cornelis et al, 2004;De Lima et al, 1992;Iserloh et al, 2013a;Ries et al, 2014). Experimental quantifications on autochthonous soils and disturbed substrates (Iserloh et al, 2013a) reveal a powerful impact of wind-driven rain on erosion rates that is highly dependent on soil surface characteristics.…”