Landslide ecological restoration using Nature-based Solutions: A case study in the Azores

<ns3:p> Landslides are common in the Azores due to orography, soil characteristics, and high rainfall, creating open spaces often colonized by invasive plant species, which degrade natural habitats in the Pico da Vara/Ribeira do Guilherme Special Protection Area (São Miguel Island). In 2015, as part of the LIFE+ Lands of Priolo project, nature-based solutions (NBS) were applied to stabilize slopes and support habitat restoration. This study evaluates the effectiveness of these interventions by monitoring five restored slopes over a ten-year period. Hydroseeding species accounted for 82.5% of total germination; although native species germinated more successfully (72.5%), exotic species were more numerous. After ten years, native species covered 87.9% of the restored slopes, though only <ns3:italic>Calluna vulgaris</ns3:italic> and <ns3:italic>Festuca francoi</ns3:italic> were originally seeded. Mosses ( <ns3:italic>Sphagnum</ns3:italic> sp.) and the fern <ns3:italic>Woodwardia radicans</ns3:italic> were abundant. Comparisons with control areas indicate successful ecological restoration. Ecological indices suggest that restored slopes tend to have lower species diversity but higher dominance. These findings demonstrate that NBS effectively stabilize slopes and support habitat recovery, as shown by the resulting biodiversity of the restored areas. </ns3:p>