Impact of Soil Biological Crusts on the Sustainability of Arid Ecosystems in Central-Western Argentina: Their Influence on Nutrient Dynamics and Soil Properties

Biological soil crusts (BSCs) are common in arid and semi-arid regions, found in vegetation patches and interpatches. However, their distribution, functionality, and composition studies are limited, especially in South America and Argentina. This study assessed the functional differences in BSCs between patches and interpatches focusing on their role as fertility islands. Sixty plots were analyzed at two sites, measuring the soil’s composition, diversity, and physical and chemical properties, including stability, compaction, temperature, moisture, nitrogen, phosphorus, organic matter, electrical conductivity, and pH. The results showed similar BSC coverage in patches and interpatches but with compositional variations: mosses dominated patches, while cyanobacteria and lichens were more common in interpatches. BSCs enhance soil stability, moisture retention, nitrogen fixation, and phosphorus availability, which are essential for soil health and ecosystem functionality. The observed variations across microenvironments are crucial for sustainability. Understanding these dynamics is vital for managing arid ecosystems, as healthy BSCs mitigate erosion, improve nutrient cycling, and enhance resilience to climate change. Preserving and managing BSCs composition and distribution are essential for the sustainability of these ecosystems in the region.