2011; Liu et al. 2013; Steven et al. 2013). Two articles of this special issue deal with this topic. Elliot et al. (2014) characterized the bacterial communities of biocrusts (0–1 cm depth) and the subsurface soil (1–2 cm depth) in the Kalahari Desert (southwest
Botswana) using a high Pifithrin �� throughput 16S ribosomal RNA gene sequencing approach. They found that biocrust bacterial communities were distinct with respect to vegetation type and soil depth, and varied in relation to soil carbon, nitrogen, and surface temperature. Cyanobacteria were predominant in the grass interspaces at the soil surface (0–1 cm) but rare in subsurface soils (1–2 cm depth) and under the shrubs and trees. Bacteroidetes were significantly more abundant in surface soils
of all areas even in the absence of a consolidated crust, whilst subsurface soils yielded more sequences affiliated to Acidobacteria, Actinobacteria, Chloroflexi, and Firmicutes. Maier et al. (2014) present a description of the prokaryotic communities found in biocrusts formed by Psora decipiens and Toninia sedifolia in the Tabernas basin (Almería, SE Spain) using 454 high throughput 16S ribosomal RNA gene sequencing approach. As found by Elliot et al. (2014), cyanobacteria were more abundant at the soil surface but rare in below-crust soils, whilst below-crust soils harbored significantly more Acidobacteria, Verrucomicrobia, Gemmatimonadetes, selleck chemicals Planctomycetes, and Armatimonadetes. Additionally, Maier et al. (2014) found that bacteria were mainly present at the upper cortex of the lichen squamules and attachment organs, in what represents an interesting fungal-bacterial interaction that merits further research. Biodiversity research with biocrusts has not been limited to the study of the taxonomic richness of their constituents, and an increasing number of researchers are focusing on other important aspects of biocrust diversity. Unlike the situation with their vascular counterparts, we know little about the diversity of ecological processes in biocrusts, Sirolimus cell line despite
its potential to improve our understanding of the maintenance of these ecosystems (Bowker et al. 2010b; Cornelissen et al. 2007). To contribute to this gap, Concostrina et al. (2014) characterized five functional traits for 31 lichens species along a rainfall gradient in Spain. They also evaluated the influence of large scale (i.e. precipitation) and small scale factors (i.e. substrate type, vegetation presence) on the functional diversity of biocrust communities. The authors found multiple trait shifts and a general increase of functional divergence with increasing precipitation. They also observed that substrate type and small scale biotic factors determined shifts in all traits studied, while these factors did not affect functional divergence as much.