Vanuatu cultural landscapes across time and space

Islands are emblematic cases of anthropogenic impacts on ecosystems. First human settlements in Remote Oceanic Islands came along with major landscape modifications. Which factors led to the failure or the establishment of a sustainable human-ecosystem interaction remains an open question. Reconstructing past human activities can help to retrieve information on the environmental responses to different degrees of change. The archipelago of Vanuatu is a key area for the recent human colonization of the Pacific (~3000 years ago), which came along with major landscape modifications and is vulnerable to extreme events and climatic changes, past, present, and future. Through the multi-proxy analysis of lakes sediment cores from the archipelago of Vanuatu, we provide paleoclimatic and paleoenvironmental reconstructions, combining geochemical tools based on biomarkers with sedimentological and palaeoecological analyses in sites with different degrees of archeological knowledge. High-resolution radiocarbon dated sedimentological records from the islands of Efate, Espiritu Santo, and Ravenga are presented and confronted against different times and modes of human occupation. Environmental reconstructions are validated with local knowledge and memories to understand indigenous communities' resilience to environmental changes observed in the cores such as extreme events (volcanic eruptions, droughts, cyclones). Tracing past land-use and climate change, on remote Pacific islands, and the response of local inhabitants to these changes highlights the links between cultural activities, such as agricultural practices, and the environment and contribute to identifying key factors related to the ecological resilience and the adaptive capacity of socio-ecological systems in changing environments.