Specific island biogeographic and landscape features shape plant diversity and habitat specialism on edaphic quartz islands in an arid ocean

Aim: Habitat islands on special soils in arid regions offer unique environmental conditions for plants and often harbour specialized and endemic floras, thus having high nature conservation value. In addition, habitat islands are characterized by distinct spatial features such as island characteristics, habitat diversity, insularity, and matrix effects. However, their role as drivers of biodiversity on habitat islands is still unclear. Therefore, we aim to quantify the extent to which island parameters, insularity metrics, habitat diversity, and the surrounding matrix, explain plant diversity on edaphic quartz islands.
Location: The quartz islands in our study area, located in the Knersvlakte Nature Reserve (South Africa), consist of naturally isolated patches covered by white quartz gravel within a zonal semi-arid vegetation matrix, hosting a unique vegetation predominantly composed of dwarf succulent shrubs.
Methods: We conducted a comprehensive field survey of the perennial flora on ..., , , # Data from: Specific island biogeographic and landscape features shape plant diversity and habitat specialism on edaphic quartz islands in an arid ocean

[https://doi.org/10.1038/s41598-025-94562-5](https://doi.org/10.1038/s41598-025-94562-5)

This dataset contains the data on which the analyses and results published in the linked research article in Scientific Reports are based. Quartz islands are edaphic habitat islands located in the arid zone of the Succulent Karoo in southern Africa. These habitat islands harbour outstanding numbers of endemic and habitat specialised plant species. Therefore, they provide unique opportunities to apply the theory of island biogeography and to analyze which effect several spatial features of this habitat island archipelago have on the species richness and the richness of endemic plant species.

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