Climate-change impacts on understorey bamboospecies and giant pandas in China'sQinlingMountains

Climate change is threatening global ecosystems through its impact on the survival of individual species and their ecological functions1,2. Despite the important role of understorey plants in forest ecosystems3–5, climate impact assessments on understorey plants and their role in supporting wildlife habitat are scarce in the literature. Here we assess climate-change impacts on understorey bamboo species with an emphasis on their ecological function as a food resource for endangered giant pandas (Ailuropoda melanoleuca). An ensemble of bamboo distribution projections associated with multiple climate-change projections and bamboo dispersal scenarios indicates a substantial reduction in the distributional ranges of three dominant bamboo species in the Qinling Mountains, China during the twenty-first century. As these three species comprise almost the entire diet of the panda population in the region, the projected changes in bamboo distribution suggest a potential shortage of food for this population, unless alternative food sources become available. Although the projections were developed under unavoidable simplifying assumptions and uncertainties, they indicate potential challenges for panda conservation and underscore the importance of incorporating interspecific interactions into climate-change impact assessments and associated conservation planning. Like many understorey plants3,4, understorey bamboo species are an essential component in many forest ecosystems6,7. They not only influence the species composition and structural complexity of forests6,7, but also provide essential food and shelter for wildlife species, including one of the most endangered species in the world, the giant panda8,9. Deforestation and forest degradation are threatening the survival of about half of all bamboo species worldwide10, and climate change may present an additional significant threat. Many bamboo species are vulnerable to climate change because their unusual extended sexual reproduction intervals (from 10 to 120 yr; ref. 11), along with limited seed dispersal ability12, render them less capable of adjusting their distributions to the rapidly changing climate projected to occur within this century1. In addition, unlike other bamboo species with rapidly growing underground stems, many understorey bamboo species in mountain ecosystems have limited vegetative dispersal ability (for example, about 0.2–0.35m yr−1 forBashania fargesii and Fargesia robusta)13,14. Despite the vulnerability of bamboo species to climate change, knowledge of climate-change-induced dynamics of