On the ratio of wind- to water-driven sediment transport: Conserving soil under global-change-type extreme events

Excerpt

Wind and water are fundamental drivers of land surface dynamics through their net effects on sediment transport and associated soil erosion. In arid and semiarid environments, where vegetation cover is usually sparse, wind- and water-driven sediment transport can potentially occur over similar spatial and temporal scales and both can contribute substantially to total erosion (Oldeman et al. 1990; Breshears et al. 2003; Field et al. 2009). Sediment transport and associated soil erosion remains a serious and persistent environmental problem worldwide because of its potential adverse impacts on soil productivity, air and water quality, and ecosystem health (Trimble and Crosson 2000; MEA 2005). Notably, roughly two-thirds of the world's arable land is affected by moderate to severe soil degradation (Pimentel et al. 1995), most of which is attributed to wind and water erosional processes (Oldeman et al. 1990). The combined impact of wind and water erosion on agricultural land translates directly into considerable financial costs (Pimentel et al. 1995), and their effects permeate across all major types of ecosystem goods and services (MEA 2005). Further, synergistic relationships between wind- and water-driven sediment transport could be particularly important in dryland ecosystems because both processes can operate on the soil surface to redistribute…