Summary1. Priority question exercises are becoming an increasingly common tool to frame future agendas in conservation and ecological science. They are an effective way to identify research foci that advance the field and that also have high policy and conservation relevance. 2. To date, there has been no coherent synthesis of key questions and priority research areas for palaeoecology, which combines biological, geochemical and molecular techniques in order to reconstruct past ecological and environmental systems on time-scales from decades to millions of years. 3. We adapted a well-established methodology to identify 50 priority research questions in palaeoecology. Using a set of criteria designed to identify realistic and achievable research goals, we selected questions from a pool submitted by the international palaeoecology research community and relevant policy practitioners. 4. The integration of online participation, both before and during the workshop, increased international engagement in question selection. 5. The questions selected are structured around six themes: human-environment interactions in the Anthropocene; biodiversity, conservation and novel ecosystems; biodiversity over long time-scales; ecosystem processes and biogeochemical cycling; comparing, combining and synthesizing information from multiple records; and new developments in palaeoecology. 6. Future opportunities in palaeoecology are related to improved incorporation of uncertainty into reconstructions, an enhanced understanding of ecological and evolutionary dynamics and processes and the continued application of long-term data for better-informed landscape management. 256-26750 priority research questions in palaeoecology 257 7. Synthesis. Palaeoecology is a vibrant and thriving discipline, and these 50 priority questions highlight its potential for addressing both pure (e.g. ecological and evolutionary, methodological) and applied (e.g. environmental and conservation) issues related to ecological science and global change.

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The charcoal record contained in lake sedimentary sequences is often used to infer past fire events. Studies to calibrate such charcoal records have been carried out in a range of mid- to high-latitude regions and relationships have been determined between size and quantity of charcoal in the sediment and proximity and spatial extent of the fires. Very little is known, however, about the relationship between fire events in savanna ecosystems and how these are represented in the charcoal record in lake sedimentary sequences. This study presents the results of a project that aimed to calibrate the micro- and macroscopic charcoal record from Kruger National Park, South Africa, with known fire events. Surface sediment samples were analysed for charcoal of different size classes and compared with data on fire proximity, area and intensity (the rate of energy released along a fire front) from fire events over the last 10 years, and the relevant source areas for micro- and macroscopic charcoal were quantified. Results indicated that (i) the Relevant Source Area of Charcoal for lakes c. 200 m diameter is between 0 and 5 km for charcoal particles >50 ∝m in length and between 10 and 15 km for charcoal particles <50 ∝m; (ii) that charcoal deposits are most likely to represent combined fire events from the preceding five years; (iii) that fire proximity, area and intensity are each significantly represented in the charcoal record, but not equally, as the signal resulting from fire intensity is stronger than that for fire proximity or area. Mathematical equations linking charcoal with fire proximity, area and intensity are presented.

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Aim  Coastal biodiversity hotspots are globally threatened by sea‐level rise. As such it is important to understand how ecosystems resist, respond and adapt to sea‐level rise. Using pollen, geochemistry, charcoal and diatom records in conjunction with previously published palaeoclimatic records, we investigated the mechanism, interactions and ecosystem response and resilience of Madagascar's littoral forest to late Holocene sea‐level rise. Location  Sediment sequences were collected along the south‐east coast of Madagascar in two adjacent habitats in Mandena; the highly diverse littoral forest fragment and species‐poor Erica‐matrix. Methods  We used a multi‐proxy approach to investigate the relative influence of environmental changes on the littoral ecosystem. We reconstructed past vegetation and fire dynamics over the past 6500 years at two sites in the littoral forest using fossil pollen and macrofossil charcoal contained in sedimentary sequences. Alongside these records we reconstructed past marine transgressions from the same sedimentary sequences using geochemical analyses, and a salinity and drought index through the analysis of fossil diatoms. Results  Our findings indicated that it was the synergistic effect of sea‐level rise coupled with rainfall deficits that triggered a threshold event with a switch from two types of littoral forest (an open Uapaca forest and a closed littoral forest fragment) to an Erica–Myrica heath/grassland occurring in approximately less than 100 years. Resilience to sea‐level rise differed in the two adjacent habitats, suggesting that the littoral forest fragment was more resilient to the impacts of sea‐level change and aridity than the open Uapaca woodland. Conclusions  We demonstrated that the littoral ecosystem was influenced by late Holocene sea‐level rise and climatic desiccation. While climate change‐integrated conservation strategies address the effects of climate change on species distribution and dispersal, our work suggests that more attention should be paid to the impacts of interactive climatic variables that affect ecosystem thresholds.