Vortrag, Island Biology 2014, Honolulu, Oahu, Hawai'i, USA: 07.07.2014 - 11.07.2014
Recent climate projections indicate substantial environmental alterations in oceanic island regions until the end of the century, setting up profound threats to the flora of oceanic islands. Inherent characteristics of island species and ecosystems (e.g. small population sizes, low habitat availability, low functional redundancy and high endemism), as well as strong anthropogenic impairments cause a particular susceptibility to climate change impacts and disproportionally high potentials for biodiversity loss. We reviewed a growing body of research, finding indication of increasing negative impacts on insular species and ecosystems. Due to low functional redundancies, disruptions of ecological interactions will probably cause high rates of co-modifications and co-extinctions on oceanic islands. The greatest endangerments come from synergistic threat factor interactions, especially from the interplay between climatic alterations and local anthropogenic encroachments on native plant species and ecosystems. However, threats from global climate change are not evenly distributed among the world’s oceanic islands but rather vary with intrinsic (e.g. island area, structure, age and ecological complexity) and extrinsic factors (regional type and strength of environmental alterations, local human influences). We identified conditions that make particular types of islands, ecosystems or species vulnerable to climate change impacts. For example, we suppose the greatest flora susceptibilities on oceanic islands of small area, low elevation and homogeneous topographic structuring (with the most threatened islands being flat atolls). The suitability of oceanic islands and their ecosystems for potential research on the field of climate change ecology is highlighted and knowledge gaps and some implications for adequate approaches are given.