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Pollen and environmental reconstruction, Holocene dynamics of tropical rainforest, climate, fire, human impact and land use in Sulawesi and Sumatra, Indonesia

The present-day configuration of Indonesia and SE Asia is the results of a long history of tectonic movements, volcanisms and global eustatic sea-level changes. Not indifferent to these dynamics, fauna and flora have been evolving and dispersing following a complicate pattern of continent-sea changes to form what are today defined as Sundaland and Wallacea biogeographical regions. The modern intraannual climate of Indonesia is generally described as tropical, seasonally wet with seasonal reversals of prevailing low-level winds (Asian-Australian monsoon). However at the interannual scale a range of influences operating over varying time scales affect the local climate in respect of temporal and spatial distribution of rainfall. Vegetation generally reflects climate and to simplify it is possible to distinguish three main ecological elements in the flora of Malaysia: everwet tropical, seasonally dry tropical (monsoon) and montane. Within those major ecological groups, a wide range of specific local conditions caused a complex biogeography which has and still attract the attention of botanists and biogeographers worldwide. Being one of the richest regions in the Worlds in terms of species endemism and biodiversity, Indonesia has recently gone through intensive transformation of previously rural/natural lands for intensive agriculture (oil palm, rubber, cocoa plantations and rice fields). Climate change represents an additional stress. Projected climate changes in the region include strengthening of monsoon circulation and increase in the frequency and magnitude of extreme rainfall and drought events. The ecological consequences of these scenarios are hard to predict. Within the context of sustainable management of conservation areas and agro-landscapes, Holocene palaeoecological and palynological studies provide a valuable contribution by showing how the natural vegetation present at the location has changed as a consequence of climate variability in the long-term (e.g. the Mid-Holocene moisture maximum, the modern ENSO onset, Little Ice Age etc.). The final aim of my PhD research is to compare the Holocene history of Jambi province and Central Sulawesi. In particular: - Reconstructing past vegetation, plant diversity and climate dynamics in the two study areas Jambi (Sumatra) and Lore Lindu National Park (Sulawesi) - Comparing the ecological responses of lowland monsoon swampy rainforest (Sumatra) and everwet montane rainforests (Sulawesi) to environmental variability (vulnerability/resilience) - Investigating the history of human impact on the landscape (shifting cultivation, slash and burn, crop cultivation, rubber and palm oil plantation) - Assessing the impact and role of droughts (El Niño) and fires - Adding a historical perspective to the evaluation of current and future changes.

Data from a multi-proxy comparison from the Little Belt (IODP Expedition 347, Site M0059: palynomorph, diatom, geochemical data)

The data published here were gathered in the framework of a multi-proxy-based study of paleotemperature (both marine and terrestrial), -salinity, and -ecosystem changes from the Little Belt (Site M0059). They cover the past ~8,000 years and contain only material from the uppermost subunits 1a and 1b encountered at Site M0059 (see e.g. Andrén et al. 2015). Four environmental zones (EZ1: oldest, freshwater conditions; EZ2 to EZ4 reflecting following salinity and ecosystem changes in the region) were identified in Kotthoff et al. (2017). The age model and the sedimentology are discussed in Kotthoff et al. (2017). The datasets comprise data for salinity proxies (diatoms, aquatic palynomorphs, diol index) and for water temperature proxies (foraminiferal Mg/Ca-ratios, long chain diol index and TEXL86) as well as temperature reconstruction based on pollen grains. It is discussed in Kotthoff et al. (2017) that applying and interpreting proxies in coastal environments and marginal seas needs particular caution. For example, foraminiferal Mg/Ca-ratios may have been influenced by contamination by authigenic coatings in the deeper intervals of the record. Lipid paleothermometers were probably influenced by significant changes in depositional settings in the Little Belt. References: Andrén, T., Jørgensen, B.B., Cotterill, C., and the Expedition 347 Scientists: Baltic Sea Paleoenvironment. Proceedings IODP, 347. College Station, TX (Integrated Ocean Drilling Program), https://doi.org/10.2204/iodp.proc.347.101.2015, 2015. Kotthoff, U., Groeneveld, J., Ash, J. L., Fanget, A.-S., Krupinski, N. Q., Peyron, O., Stepanova, A., Warnock, J., Van Helmond, N. A. G. M., Passey, B. H., Clausen, O. R., Bennike, O., Andrén, E., Granoszewski, W., Andrén, T., Filipsson, H. L., Seidenkrantz, M.-S., Slomp, C. P., and Bauersachs, T.: Reconstructing Holocene temperature and salinity variations in the western Baltic Sea region: a multi-proxy comparison from the Little Belt (IODP Expedition 347, Site M0059), Biogeosciences, 14, 5607–5632, https://doi.org/10.5194/bg-14-5607-2017, 2017.

Pollen record of surface samples from mire Weisses Lauch in Niederlausitz, Brandenburg, Germany

Pollen record of surface samples from mire Pastlingsee in Niederlausitz, Brandenburg, Germany

Late Glacial and Holocene palynological data from Füramoos, Southwestern Germany

Palynological data from the Late Glacial and Holocene (c. 14500 – 200 yrs cal. BP) obtained from an ombrotrophic peat bog at Füramoos (southern Germany).

REVEALS land-cover reconstructions for Europe during the Late Pleistocene (75-15 ka BP)

We present the first pollen-based REVEALS land-cover reconstructions of Europe during the late Last Glacial period from Europe. The results are based on fossil pollen data from 61 sites in Europe and bordering regions, using 38 plant taxa in total. The reconstruction uses the "Regional Estimates of VEgetation Abundance from Large Sites"(REVEALS) model that factors in the relative pollen productivity (RPPs) and fall speed of pollen (FSP) (Sugita, 2007). All REVEALS estimates and their Standard Erorrs are given in proportions for each site in 1kyr time steps from 75 to 15 ka BP. Moreover, we provide the RPP and FSP table, which was adapted from Githumbi et al. (2022) and Serge et al. (2023). We also include REVEALS land-cover reconstructions of the same dataset, using the RPP compilation of Wieczorek & Herzschuh (2020) as well as optimized RPP data after Schild et al. (2024) to highlight the impact of different RPP data on REVEALS land-cover reconstructions.

Percentages of pollen data from late MIS 6 to MIS 1 from Füramoos, Southern Germany

High-resolution palynological data (taxa and groups) from the Füramoos peat bog. The data span from the latest Rissian glaciation (MIS 6) to the present (MIS 1) at an average temporal resolution of ~230 years and are given as percentages and a depth and age scale. The data highlight the presence of several forest expansions and contractions associated with Greenland Interstadials / Dansgaard-Oeschger Events during MIS 3 and 4. Interglacials (MIS 1 and 5e) are characterized by the establishment of a dense temperate forest and the Early Glacial (MIS 5d-5a) is marked by a persistent boreal forest. Pollen data from the Late Glacial and Holocene (14.5 - 0 ka BP) has been incorporated from Kern et al. (2021).

Late Glacial and Holocene lead isotopes and lead concentration data from Füramoos, Southwestern Germany

Lead concentration and stable isotopes were analysed using inductively coupled plasma mass spectrometry (ICP-MS) in samples from an ombrotrophic peat bog at Füramoos (southern Germany).

Pollen and environmental reconstruction, Pollen und Umweltrekonstruktion - Pleistozäne und holozäne Umweltveränderungen im brasilianischen Amazonasgebiet

Amazonien, das größte zusammenhängende Regenwaldökosystem der Erde, beherbergt eine enorme Artenvielfalt und spielt eine entscheidende Rolle für das globale Klima, den Kohlenstoffhaushalt sowie für den Wasserkreislauf. Trotz der enormen Bedeutung des Amazonasregenwaldes für heutige und zukünftige weltweite Umweltveränderungen ist nur wenig über seine Vergangenheit bekannt. Zur Untersuchung der spätquartären Umweltdynamik stehen uns mehrere Seesediment- und Sumpfkerne aus Regionen des brasilianischen Amazonasgebietes zur Verfügung, nördlich und südlich des Äquators gelegen. Die zeitlich hochauflösende Analyse der vorliegenden Sedimentkerne auf Pollenmaterial, Holzkohlepartikel, Sedimente und Isotope, als auch Radiokarbondatierungen und multivariate Datenanalysen, sollen im Einzelnen Aufschluss geben über: - Veränderungen in Vegetation und Artenvielfalt, - Klimaveränderungen einschließlich der Dynamik der Innertropischen Konvergenzzone (ITCZ) und der Rolle von El Niño Southern Oscillation (ENSO) Ereignissen, - die Feuergeschichte und ihren Einfluss auf das Ökosystem und - anthropogene Einflüsse.

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