Dust deposition in southern Nevada and California, 1984–1989: Relations to climate, source area, and source lithology

Abstract

Dust samples collected annually for 5 years from 55 sites in southern Nevada and California provide the first regional source of information on modern rates of dust deposition, grain size, and mineralogical and chemical composition relative to climate and to type and lithology of dust source. The average silt and clay flux (rate of deposition) in southern Nevada and southeastern California ranges from 4.3 to 15.7 g/m2/yr, but in southwestern California the average silt and clay flux is as high as 30 g/m2/yr. The climatic factors that affect dust flux interact with each other and with the factors of source type (playas versus alluvium), source lithology, geographic area, and human disturbance. Average dust flux increases with mean annual temperature but is not correlated to decreases in mean annual precipitation because the regional winds bring dust to relatively wet areas. In contrast, annual dust flux mostly reflects changes in annual precipitation (relative drought) rather than temperature. Although playa and alluvial sources produce about the same amount of dust per unit area, the total volume of dust from the more extensive alluvial sources is much larger. In addition, playa and alluvial sources respond differently to annual changes in precipitation. Most playas produce dust that is richer in soluble salts and carbonate than that from alluvial sources (except carbonate‐rich alluvium). Gypsum dust may be produced by the interaction of carbonate dust and anthropogenic or marine sulfates. The dust flux in an arid urbanizing area may be as much as twice that before disturbance but decreases when construction stops. The mineralogic and major‐oxide composition of the dust samples indicates that sand and some silt is locally derived and deposited, whereas clay and some silt from different sources can be far‐traveled. Dust deposited in the Transverse Ranges of California by the Santa Ana winds appears to be mainly derived from sources to the north and east.

Dust: Small‐scale processes with global consequences

“…Yet a growing body of literature reveals that vegetated landscapes and dune fields can emit dust [Bullard et al, 2008;Rivera Rivera et al, 2009] (Figure 1). Recent advances using satellite data over northern Africa have also shown that dust sources may be more diverse than previously believed [Schepanski et al, 2007], and in the Mojave Desert of the southwestern United States, alluvial fans and plains may be larger overall contributors to total dust emission than dry lakes [Reheis and Kihl, 1995].…”

Aeolian dust in Colorado Plateau soils: Nutrient inputs and recent change in source

“…M any studies have addressed the presence of aeolian dust in soils and surficial deposits in deserts to provide important geologic and ecologic information bearing on landscape dynamics (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16). From this body of work, we have improved understanding about: (i) current and past sources and flux of dust, hence changing conditions of dust emission; (ii) the genesis of desert soils; (iii) the influences of aeolian silt and clay on water-infiltration rates in soil; (iv) the evolution of desert surfaces (such as desert pavement) relevant to surface stability, as well as the distribution of surface and subsurface water; and (v) interrelations among aeolian dust, distribution of plants and soil crust, rain-water runoff, and productivity.…”

Characteristics and composition of the falling dust in urban environment

“…Shuwaikh city (Kuwait), based on this study, followed Bina of India in dust fall with an average amount of 53.7 ton km -2 month -1 , which is indeed expected as it is located in an arid region, and it is located within one of the five major regions where dust originates. Areas in North and Northwest India exhibited intermediate value (21 ton km -2 -month -1 ) of dust fall (Yadav and Rajamani 2006), followed by Nagev desert (Offer and Goossen 2001), Lanzhou (Liu et al 2004), Texas (Crabtree 2005), Yazd (Naddafi et al 2006), Arizona (Crabtree 2005), California (Crabtree 2005), and Southern Nevada (Reheis and Kihl 1995), as shown in Fig. 5.…”