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Collection of conference abstracts presented at the vDEUQUA2021 (2021-09-30 to 2021-09-01), the virtual meeting of the German Quaternary Association (DEUQUA).

International audience; The southern Cape is a key focus for southern African palaeoenvironmental research as it represents the transitional region between temperate westerlies and subtropical rainfall sources. This study presents pollen, plant biomarker, geochemical and charcoal data preserved in the Rietvlei wetland. The bulk of the record spans the last 16 ka, but it also provides rare insights into late Marine Oxygen Isotope Stage (MIS) 3 (ca. 35–30k cal a BP). The data suggest that during the Pleistocene the development and permanence of this wetland was probably influenced by sea-level change via control on the local water table; notably lower sea levels within MIS 2 resulted in very limited wetland productivity. The MIS 3 section provides evidence both supporting previous suggestions of relatively humid conditions, but also some indication of periodic arid phases. The Holocene record suggests clear contrasts between the early (11–7k cal a BP; relatively humid), mid-Holocene (7–3.3k cal a BP; more arid, less productive wetland conditions) and latest Holocene (last 2k cal a BP; resurgence in both fynbos and aquatic/riparian pollen). While isolating the roles of winter/summer rainfall remains challenging, these data clarify the nature of change during key episodes in the regional palaeoenvironmental record.

Interpretations of fossil pollen data are often limited to broad, qualitative assessments of past climatic and environmental conditions (e.g.colder vs. warmer, wetter vs. drier, open vs. closed landscape). These assessments can be particularly imprecise in regions such as southern Africa, where botanical biodiversity is high, and there exists an associated uncertainty regarding the climatic/environmental sensitivities of the plants contributing to a given pollen type. This atlas addresses this limitation by characterising the climate sensitivities of the 140 pollen morphotypes most often recorded in late Quaternary palaeoecology studies in southern Africa, relying on their parent plant distributions as one of the basic factors that determine their presence. The atlas is designed as a suite of graphical diagnostic tools and photographs together with analyses of the modern geographical distribution of more than 22,000 plant species to identify their primary climatic sensitivities across southern Africa. Together, the elements included span the complete workflow from pollen identification through interpretation and climate reconstruction.&nbsp

Interpretations of fossil pollen data are often limited to broad, qualitative assessments of past climatic and environmental conditions (e.g. colder vs. warmer, wetter vs. drier, open vs. closed landscape). These assessments can be particularly imprecise in regions such as southern Africa, where botanical biodiversity is high, and there exists an associated uncertainty regarding the climatic/environmental sensitivities of the plants contributing to a given pollen type. This atlas addresses this limitation by characterising the climate sensitivities of the 140 pollen morphotypes most often recorded in late Quaternary palaeoecology studies in southern Africa, relying on their parent plant distributions as one of the basic factors that determine their presence. The atlas is designed as a suite of graphical diagnostic tools and photographs together with analyses of the modern geographical distribution of more than 22,000 plant species to identify their primary climatic sensitivities across southern Africa. Together, the elements included span the complete workflow from pollen identification through interpretation and climate reconstruction., {"references":["Chevalier, M., 2019. Enabling possibilities to quantify past climate from fossil assemblages at a global scale. Glob. Planet. Change 175, 27–35. doi:10.1016/j.gloplacha.2019.01.016","Chevalier, M., Cheddadi, R., Chase, B.M., 2014. CREST (Climate REconstruction SofTware): a probability density function (PDF)-based quantitative climate reconstruction method. Clim. Past 10, 2081–2098. doi:10.5194/cp-10-2081-2014","Chevalier, M., 2018. GBIF database for CREST. doi:10.6084/m9.figshare.6743207","Fick, S.E., Hijmans, R.J., 2017. WorldClim 2: new 1-km spatial resolution climate surfaces for global land areas. Int. J. Climatol. 37, 4302–4315. doi:10.1002/joc.5086","Trabucco, A., Zomer, R.J., Bossio, D.A., van Straaten, O., Verchot, L. V., 2008. Climate change mitigation through afforestation/reforestation: A global analysis of hydrologic impacts with four case studies. Agric. Ecosyst. Environ. 126, 81–97. doi:10.1016/j.agee.2008.01.015","Trabucco, A., Zomer, R.J., 2019. Global Aridity Index and Potential Evapotranspiration (ET0) Climate Database v2. doi:10.6084/m9.figshare.7504448.v3","Olson, D. M., Dinerstein, E., Wikramanayake, E. D., Burgess, N. D., Powell, G. V. N., Underwood, E. C., D'amico, J. A., Itoua, I., Strand, H. E., Morrison, J. C., Loucks, C. J., Allnutt, T. F., Ricketts, T. H., Kura, Y., Lam- oreux, J. F., Wettengel, W. W., Hedao, P., and Kassem, K. R.: Terrestrial ecoregions of the world a new map of life on Earth, BioScience, 51, 933–938, 2001.","GBIF: Global Biodiversity Information Facility [WWW Document], 2018. URL https://www.gbif.org","GBIF.org, 2020a. Anthocerotopsida occurrence data downloaded on September 24th, 2020. doi:10.15468/dl.t9zenf","GBIF.org, 2020b. Cycadopsidae occurrence data downloaded on September 24th, 2020. doi:10.15468/dl.sfjzxu","GBIF.org, 2020c. Liliopsida occurrence data downloaded on September 24th, 2020. doi:10.15468/dl.axv3yd","GBIF.org, 2020d. Polypodiopsida occurrence data downloaded on September 24th, 2020. doi:10.15468/dl.87tbp6","GBIF.org, 2020e. Gnetopsidae occurrence data downloaded on September 24th, 2020. doi:10.15468/dl.h2kjnc","GBIF.org, 2020f. Gingkoopsidae occurrence data downloaded on September 24th, 2020. doi:10.15468/dl.da9wz8","GBIF.org, 2020g. Pinopsidae occurrence data downloaded on September 24th, 2020. doi:10.15468/dl.x2r7pa","GBIF.org, 2020h. Magnoliopsida occurrence data downloaded on September 24th, 2020. doi:10.15468/dl.ra49dt","GBIF.org, 2020i. Lycopodiopsida occurrence data downloaded on September 24th, 2020. doi:10.15468/dl.ydhyhz"]}

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