Effects of biological soil crusts on a Mediterranean perennial grass (Stipa tenacissima L.)

In the last decades, there has been a growing interest on evaluating the effects of biological soil crusts (hereafter, biocrusts) on vascular plants. The purpose of this paper was to investigate the influence of biocrusts on Stipa tenacissima, key species in arid and semi-arid environments of the Mediterranean Basin. In fact, we explored the impact of biocrusts removal underneath S. tenacissima on soil chemical properties and leaf mineral uptake. Indeed, we studied the effect of mixed biocrusts on the seed germination of S. tenacissima under laboratory conditions. The research showed a greater availability of soil resources correlated with enhanced leaf nutrient levels of bioessential elements in the presence of intact biocrusts compared to fragmented biocrusts underneath S. tenacissima tussocks. We suggest that this is related to the loss of soil moisture as a result of biocrusts removal. In addition, we found that mixed biocrusts favored seed germination and viability of S. tenacissima. By improving soil chemical properties and leaf nutrient uptake, biocrusts can provide enhanced growth conditions for Stipa tenacissima. These findings with the positive effect on seed germination suggest that biocrusts can be used in the restoration of S. tenacissima.