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Background and Aims: Low-altitude mountains constitute important centres of diversity in landscapes with little topographic variation, such as the Southwest Australian Floristic Region (SWAFR). They also provide unique climatic and edaphic conditions that may allow them to function as refugia. We investigate whether the Porongurups (altitude 655 m) in the SWAFR will provide a refugium for the endemic Ornduffia calthifolia and O. marchantii under forecast climate change., Methods: We used species distribution modelling based on WorldClim climatic data, 30-m elevation data and a 2-m-resolution LiDAR-derived digital elevation model (DEM) to predict current and future distributions of the Ornduffia species at local and regional scales based on 605 field-based abundance estimates. Future distributions were forecast using RCP2.6 and RCP4.5 projections. To determine whether local edaphic and biotic factors impact these forecasts, we tested whether soil depth and vegetation height were significant predictors of abundance using generalized additive models (GAMs)., Key Results: Species distribution modelling revealed the importance of elevation and topographic variables at the local scale for determining distributions of both species, which also preferred shadier locations and higher slopes. However, O. calthifolia occurred at higher (cooler) elevations with rugged, concave topography, while O. marchantii occurred in disturbed sites at lower locations with less rugged, convex topography. Under future climates both species are likely to severely contract under the milder RCP2.6 projection (approx. 2 °C of global warming), but are unlikely to persist if warming is more severe (RCP4.5). GAMs showed that soil depth and vegetation height are important predictors of O. calthifolia and O. marchantii distributions, respectively., Conclusions: The Porongurups constitute an important refugium for O. calthifolia and O. marchantii, but limits to this capacity may be reached if global warming exceeds 2 °C. This capacity is moderated at local scales by biotic and edaphic factors., (© The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Restoration interventions require knowledge on the suitability of seed sources. Provenance delineation for ecological restoration of degraded environments has begun to incorporate genome‐wide information on adaptive variation, but this has only been completed on a small number of plant species. Rarely is provenance delineation using a genomics approach applied to species occurring across different habitats, and in the context of future climate scenarios, despite their potential importance for successful long‐term restoration. Here, we use neutral genetic data to investigate patterns of genetic differentiation and a landscape genomics approach to model putatively adaptive genetic variation under multiple climate scenarios for two species co‐occurring in a predominantly mesic environment, and two species co‐occurring in a semi‐arid environment. We then determine the genetic similarity of seed sourcing locations to hypothetical restoration sites, both under current and future climate scenarios. We found that the geographical extent of provenances and the amount of genetic change required to track the projected climatic conditions over time differed within the pairs of co‐occurring species, and between habitats. Additionally, future climate scenarios had differing effects on provenance patterns between the two landscapes indicating a differential response to changing climate between species from mesic and arid habitats. This implies that provenance guidelines can be both species and habitat dependent. We discuss how these results can be utilized to design seed sourcing strategies for successful restoration, and how these methods could be more broadly applied to delineate provenances of other species and locations. [ABSTRACT FROM AUTHOR]