Climate and land-use change drive population decline in a red-listed plant species

Highlights • Accelerating climate change may become an increasing threat to rare plant species. • Threatened Pulsatilla patens has lost several of its populations in Finland. • Land use and climate change pose additive effects on P. patens. • Advanced flowering triggered by warm spells exposes P. patens to spring frost. Abstract Land-use change is a perennial driver of biodiversity decline. However, climate change may pose novel pressures on species populations, adding to the mixture of anthropogenic threats. Determining the main causes for species decline is important for effective allocation of conservation efforts and for understanding the linkages between biodiversity decline and climate change. Here, we study the impacts of forest management, urbanization, and changes in spring climatic conditions on the presence of a threatened plant species, Pulsatilla patens. In addition, we examine if topographic heterogeneity has supported the persistence of species populations under climatic change starting from 1961. We modelled the effect of land-use and climate change both separately and jointly, finding that both drivers have individual and potentially direct impacts on the persistence of P. patens. This is in agreement with the historic standpoint of land-use change being the main threat for the species, as well as recent findings of the potentially harmful effects of altered climatic conditions in spring, e.g., through late frost damage following earlier emergence of flowers. However, we found no indication that topographic heterogeneity would offer a buffering effect, suggesting that changes in spring climatic conditions form a tangible threat to this species that is not alleviated in the current landscape. As climate change continues, it is likely that the number and intensity of stressors increases for a variety of species, which warrants further attention to the role of climate change and appropriate conservation action.