Pointing and Belnap (2014) review regional-scale impacts arising from the disturbance of dryland soils and the biocrust communities living on them. They identify the causes of disturbance, emphasize the mobilization of dust to the atmosphere as a major driver of these impacts, and discuss the negative environmental consequences for terrestrial and marine ecosystems, including potential threats to biotic communities and

human health. Major efforts of biocrust researchers have traditionally been devoted to understanding their role in controlling soil and wind erosion (e.g. Eldridge and Greene 1994; Belnap and Gillette 1998; Bowker et al. 2008), and to study the factors influencing the hydrological behavior of biocrusts (e.g. Belnap 2006; Eldridge et al. 2010; Rodríguez-Caballero selleck chemical et al. 2013). Two articles in this issue deal with these topics. Zhao et al. (2014) evaluate the response of biocrusts of different successional stages to raindrop erosivity Citarinostat price in the northern Shaanxi province of China. Despite the large number of studies on this topic, research separating the multiple mechanisms of erosion control by biocrusts has been limited. These authors

found that biocrusts dramatically improved the resistance of the soil to erosion, and that the biocrust effect varied with both biocrust species composition and the successional stage. Their results suggest that the influence

of biocrusts can be incorporated into erosion models. The microstructure of the soil underneath biocrusts is one of the factors affecting their hydrological behavior (Belnap 2006). Felde et al. (2014) investigated the change of the pore system of three different successional stages of biocrusts in the NW Negev Desert (Israel) to describe the influence of the soil microstructure of biocrusts on water redistribution. They reported that the pore system undergoes significant the changes during crust succession; total porosity, as well as the pore sizes significantly increased from cyanobacteria- to lichen- and moss-dominated biocrusts, and the pore geometry changed from tortuous to straight pore shapes throughout this succession. The authors conclude that the influences of the structural properties of biocrusts must be considered to a much greater extent when investigating their hydrological behavior. While diversity assessments of above-ground biocrust constituents, like mosses, liverworts, and lichens, have been conducted for many years (e.g. Crespo 1973; Büdel et al. 2009; Buschardt 1979; Eldridge and Tozer 1996; Gutiérrez and Casares 1994; Rogers 2006), researchers have recently started to explore the diversity of microorganisms associated to biocrusts (e.g. Bates et al.