Desertification, a process of land degradation fueled by climate change and unsustainable human activities such as deforestation, is a growing threat to the Caatinga and other dryland ecosystems worldwide. This degradation is stripping the land of its native vegetation and impoverishing the soil. Yet even under these harsh conditions, life persists. Biological soil crusts, composed of a diverse community of bacteria, fungi and other organisms, form a living “skin” on the soil surface and act as oases of life by stabilizing the soil and preventing erosion. This project aims to elucidate the composition and evolution of these remarkable crusts in the desertified areas of the Caatinga. We will identify the key microorganisms involved and their morphology, genetics and physiology using traditional techniques (in vitro cultivation, laboratory analysis) and state-of-the-art genetic sequencing. Our ultimate goal is to develop methods to induce the growth of biological soil crusts and harness their potential as a nature-based solution to combat desertification and restore the health of the Caatinga.