Interactions between land use, pathogens, and climate change in the Monte Pisano, Italy 1850–2000

Context: Climate change, land use change, invasive species, and pests can combine to cause changes in species distributions. However, unlike climate change, future land use and ecological interactions are unpredictable. One strategy for confronting this unpredictability is to use interdisciplinary approaches. Objectives: In this paper we demonstrate how historical ecology and SDM modeling can be combined to reconstruct the impacts of land use change, invasive pathogens, and climate change upon the landscape of the Monte Pisano of Central Italy over the last two centuries. Methods: Species distribution and climate modeling are combined with early nineteenth century land use records and oral history, in order to reconstruct changes in species distributions of sweet chestnut and maritime pine on the Monte Pisano (Central Italy). Results: The extent of pine forest tripled while chestnut forest halved since 1850. Climatic conditions changed, with temperatures increasing by over 1.5 °C. These climatic changes are insufficient to account for the shift in chestnut and pine distribution, which was mainly driven by socioeconomic change that caused changes in land use, a process accelerated by pathogens that eliminated low elevation chestnut groves. Conclusions: In Mediterranean mountains, where human activities have impacted biota for a long time, changes in land management and climate change interacting on different temporal scales, can affect the magnitude of changes in species distributions. The effects of climate change can be partially addressed through changing land use, including by reducing fire frequency or improved phytosanitary controls.