Shrinking water bodies as hotspots of sand and dust storms: The role of land degradation and sustainable soil and water management

Abstract

Sand and Dust Storms (SDS) are a natural phenomenon with important impacts on ecosystems and human society. SDS hotspots are mostly located in drylands, however their impact goes beyond national and regional boundaries, making them a global issue. Factors affecting SDS occurrence include weather and climate, land cover and soil surface conditions, geomorphology and terrain types. “Playas”, the exposed beds of shrinking water bodies, play a significant role in dust generation. Land degradation and desertification processes play an important role on dust emission from playa sources, which is frequently triggered or increased by human activities such as unsustainable land and water use upstream, reduced vegetation cover on and around playas, and mechanical disturbance of the playa surfaces.It has been estimated that anthropogenic playa sources contribute 85% of global anthropogenic dust emissions. Anthropogenic playa sources are frequently located near human settlements, so that even relatively small dust sources can have severe socio-economic and environmental impacts, including soil salinization and soil pollution when playa sediments are salt-rich or polluted. In these contexts, the implementation of sustainable land and water management (SLWM) measures and integrated watershed planning is particularly urgent to reduce dust emission and its impacts. The United Nations Conventions to Combat Desertification (UNCCD) identified the mitigation of anthropogenic SDS sources as a major pillar towards combating SDS.The number of scientific articles addressing this issue is rapidly increasing, but our understanding of SDS emitted from anthropogenic playa sources remains limited and fragmented. This article reviews the literature on playa sources that are recognized to be mainly anthropogenic in nature, with particular focus on the anthropogenic drivers, the SDS-related impacts, and the possible SLWM-based solutions to reduce SDS impact.