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Pollen record of a sediment core from the Neualbenreuth Maar, Germany

The Neualbenreuth Maar (49°58' N, 12°28' E, 601 m asl) is a filled up former maar lake, located within a presently swampy depression 2.5 km ESE of the village Neualbenreuth (NE-Bavaria, Germany). It represents one of four hitherto known volcanic structures of Pleistocene age along the NNW-SSE trending Tachov fault zone. The maar structure was detected by gravity surveys and was subsequently confirmed by the recovery of lake sediments by an exploratory drilling campaign in 2015. Within the scope of a pilot study, a set of 141 pollen samples collected from sediment depths between 17.7 to 96.0 m below the recent surface. The samples were analyzed in order to evaluate the potential of the sequence for detailed palaeoenvironmental investigations, and to estimate the age of the sedimentary record. The pollen analyses from the Neualbenreuth Maar sediments reveal a continuous record of vegetation and climate changes encompassing four interglacial stages and five cold periods. The dominance of cold and dry tolerant herbs and the sparse representation trees and shrubs during most parts of the sequence indicates open landscapes of steppe to woody-steppe character typically of late Middle and Late Pleistocene glacial periods in Central Europe. The pollen assemblages of the warm stage in the upper part of the core clearly support its correlation with the Eemian interglacial (MIS 5e). The three pre-Eemian warm stages represent terrestrial analogues of the marine isotope stages (MIS) 7e, 7c, and 7a within the Saalian glacial period. In Central Europe, which was strongly affected by glacial and periglacial processes during the major Middle and Late Pleistocene cold periods, palaeoecological evidence of the Saalian complex of alternating warm and cold stages is ambiguous so far. The Neualbenreuth record provides the first biostratigraphical sequence from this region covering MIS 8 to 5 without notable depositional gaps

Results of palynological analysis from 2020 of the varved MO-05 core from Lake Mondsee (Austria) section (249-526 cm)

This study reports a precisely dated pollen record with a 20-year resolution from the varved sediments of Lake Mondsee in the north-eastern European Alps (47°49′N, 13°24′E, 481 m above sea level). The analysed part of core spans the interval between 1500 BCE and 500 CE and allows changes in vegetation composition in relation to climatic changes and human activities in the catchment to be inferred. Intervals of distinct but modest human impact are identified at ca. 1450-1220, 740-490 and 340-190 BCE and from 80 BCE to 180 CE. While the first two intervals are synchronous with prominent salt mining phases during the Bronze Age and Early Iron Age at the nearby UNESCO World Heritage Site of Hallstatt, the last two intervals fall within the Late Iron Age and Roman Imperial Era, respectively. Comparison with published records of extreme runoff events obtained from the same sediment core shows that human activities (including agriculture and logging) around Lake Mondsee were low during intervals of high flood frequency as indicated by a higher number of intercalated detrital event layers, but intensified during hydrologically stable intervals. Comparison of the pollen percentages of arboreal taxa with the stable oxygen isotope and potassium ion records of the NGRIP and GISP2 ice cores from Greenland reveals significant positive correlations for Fagus and negative correlations for Betula and Alnus. This underlines the sensitivity of vegetation around Lake Mondsee to temperature fluctuations in the North Atlantic as well as to moisture fluctuations controlled by changes in the intensity of the Siberian High and the North Atlantic Oscillation (NAO) regime.

Global optimized REVEALS reconstruction of past vegetation cover for taxonomically harmonized pollen data sets

This data set presents the reconstructed vegetation cover for 3083 sites based on harmonized pollen data from the data set LegacyPollen 2.0 (https://doi.pangaea.de/10.1594/PANGAEA.965907) and optimized RPP values. 1115 sites are located in North America, 1435 in Europe, and 533 in Asia. Sugita's REVEALS model (2007) was applied to all pollen records using REVEALSinR from the DISQOVER package (Theuerkauf et al. 2016). Pollen counts were translated into vegetation cover by taking into account taxon-specific pollen productivity and fall speed. Additionally, relevant source areas of pollen were also calculated using the aforementioned taxon-specific parameters and a gaussian plume model for deposition and dispersal. In this optimized reconstruction, relative pollen productivity estimates for the ten most common taxa were first optimized by using reconstructed tree cover from modern pollen samples and LANDSAT remotely sensed tree cover (Townshend 2016) for North America, Europe, and Asia. Values for non-optimized taxa for relative pollen productivity and fall speed were taken from the synthesis from Wiezcorek and Herzschuh (2020). The average values from all Northern Hemisphere values were used where taxon-specific continental values were not available. We present tables with optimized reconstructed vegetation cover for all Europe, North America and Asia. As further details we list a table with the taxon-specific parameters used and a list of parameters adjusted in the default version of REVEALSinR.

Macroremains records of sediment core JW2 (Jungferweiher infilled maar), Eifel, Germany

Pollen were analyzed in a total of 560 lake sediment samples from four Eifel maars (lake Holzmaar, Jungferweiher infilled maar, Dehner infilled maar, Hoher List infilled maar). The results were combined with seven already published pollen records from Schalkenmehrener Maar (Sirocko et al., 2016, doi:10.1016/j.gloplacha.2016.03.005), Holzmaar (Sirocko et al., 2016, doi:10.1016/j.gloplacha.2016.03.005), Auel infilled maar (Britzius & Sirocko, 2023 (doi:10.3390/quat6030044) and Sirocko et al., 2022 (doi:10.1038/s41598-022-22464-x)), Dehner infilled maar (Sirocko et al., 2013, doi:10.1016/j.quascirev.2012.09.011), and Hoher List infilled maar (Sirocko et al., 2005 doi:10.1038/nature03905) to form the ELSA-23-Pollen-Stack covering the past 132,000 years. The pollen stack is complemented by a record of macroremains from Jungferweiher.

Pollen records of sediment core JW3 (Jungferweiher infilled maar), Eifel, Germany

Pollen were analyzed in a total of 560 lake sediment samples from four Eifel maars (lake Holzmaar, Jungferweiher infilled maar, Dehner infilled maar, Hoher List infilled maar). The results were combined with seven already published pollen records from Schalkenmehrener Maar (Sirocko et al., 2016, doi:10.1016/j.gloplacha.2016.03.005), Holzmaar (Sirocko et al., 2016, doi:10.1016/j.gloplacha.2016.03.005), Auel infilled maar (Britzius & Sirocko, 2023 (doi:10.3390/quat6030044) and Sirocko et al., 2022 (doi:10.1038/s41598-022-22464-x)), Dehner infilled maar (Sirocko et al., 2013, doi:10.1016/j.quascirev.2012.09.011), and Hoher List infilled maar (Sirocko et al., 2005 doi:10.1038/nature03905) to form the ELSA-23-Pollen-Stack covering the past 132,000 years. The pollen stack is complemented by a record of macroremains from Jungferweiher.

Pollen records of sediment core DE2 (Dehner infilled maar), Eifel, Germany

Pollen were analyzed in a total of 560 lake sediment samples from four Eifel maars (lake Holzmaar, Jungferweiher infilled maar, Dehner infilled maar, Hoher List infilled maar). The results were combined with seven already published pollen records from Schalkenmehrener Maar (Sirocko et al., 2016, doi:10.1016/j.gloplacha.2016.03.005), Holzmaar (Sirocko et al., 2016, doi:10.1016/j.gloplacha.2016.03.005), Auel infilled maar (Britzius & Sirocko, 2023 (doi:10.3390/quat6030044) and Sirocko et al., 2022 (doi:10.1038/s41598-022-22464-x)), Dehner infilled maar (Sirocko et al., 2013, doi:10.1016/j.quascirev.2012.09.011), and Hoher List infilled maar (Sirocko et al., 2005 doi:10.1038/nature03905) to form the ELSA-23-Pollen-Stack covering the past 132,000 years. The pollen stack is complemented by a record of macroremains from Jungferweiher.

Pollen records of sediment core HL4 (Hoher List infilled maar), Eifel, Germany

Pollen were analyzed in a total of 560 lake sediment samples from four Eifel maars (lake Holzmaar, Jungferweiher infilled maar, Dehner infilled maar, Hoher List infilled maar). The results were combined with seven already published pollen records from Schalkenmehrener Maar (Sirocko et al., 2016, doi:10.1016/j.gloplacha.2016.03.005), Holzmaar (Sirocko et al., 2016, doi:10.1016/j.gloplacha.2016.03.005), Auel infilled maar (Britzius & Sirocko, 2023 (doi:10.3390/quat6030044) and Sirocko et al., 2022 (doi:10.1038/s41598-022-22464-x)), Dehner infilled maar (Sirocko et al., 2013, doi:10.1016/j.quascirev.2012.09.011), and Hoher List infilled maar (Sirocko et al., 2005 doi:10.1038/nature03905) to form the ELSA-23-Pollen-Stack covering the past 132,000 years. The pollen stack is complemented by a record of macroremains from Jungferweiher.

REVEALS reconstruction of past vegetation cover with optimized RPP values for European samples

This data set presents the reconstructed vegetation cover for 1451 European sites based on harmonized pollen data from the data set LegacyPollen 2.0 and optimized RPP values. Sugita's REVEALS model (2007) was applied to all pollen records using REVEALSinR from the DISQOVER package (Theuerkauf et al. 2016). Pollen counts were translated into vegetation cover by taking into account taxon-specific pollen productivity and fall speed. Additionally, relevant source areas of pollen were also calculated using the aforementioned taxon-specific parameters and a gaussian plume model for deposition and dispersal and forest cover was reconstructed. In this optimized reconstruction, relative pollen productivity estimates for the ten most common taxa were first optimized by using reconstructed tree cover from modern pollen samples and LANDSAT remotely sensed tree cover (Sexton et al. 2013) for Europe. Values for non-optimized taxa for relative pollen productivity and fall speed were taken from the synthesis from Wiezcorek and Herzschuh (2020). The average values from all Northern Hemisphere values were used where taxon-specific continental values were not available. We present tables with optimized reconstructed vegetation cover for all records in Europe. As further details we list a table with the taxon-specific parameters used and a list of parameters adjusted in the default version of REVEALSinR.

REVEALS reconstruction of past vegetation cover with optimized RPP values for Asian samples

This data set presents the reconstructed vegetation cover for 706 Asian sites based on harmonized pollen data from the data set LegacyPollen 2.0 and optimized RPP values. Sugita's REVEALS model (2007) was applied to all pollen records using REVEALSinR from the DISQOVER package (Theuerkauf et al. 2016). Pollen counts were translated into vegetation cover by taking into account taxon-specific pollen productivity and fall speed. Additionally, relevant source areas of pollen were also calculated using the aforementioned taxon-specific parameters and a gaussian plume model for deposition and dispersal and forest cover was reconstructed. In this optimized reconstruction, relative pollen productivity estimates for the ten most common taxa were first optimized by using reconstructed tree cover from modern pollen samples and LANDSAT remotely sensed tree cover (Sexton et al. 2013) for Asia. Values for non-optimized taxa for relative pollen productivity and fall speed were taken from the synthesis from Wiezcorek and Herzschuh (2020). The average values from all Northern Hemisphere values were used where taxon-specific continental values were not available. We present tables with optimized reconstructed vegetation cover for records in Asia. As further details we list a table with the taxon-specific parameters used and a list of parameters adjusted in the default version of REVEALSinR.

Pollen records of sediment core HM4 from lake Holzmaar, Eifel, Germany

Pollen were analyzed in a total of 560 lake sediment samples from four Eifel maars (lake Holzmaar, Jungferweiher infilled maar, Dehner infilled maar, Hoher List infilled maar). The results were combined with seven already published pollen records from Schalkenmehrener Maar (Sirocko et al., 2016, doi:10.1016/j.gloplacha.2016.03.005), Holzmaar (Sirocko et al., 2016, doi:10.1016/j.gloplacha.2016.03.005), Auel infilled maar (Britzius & Sirocko, 2023 (doi:10.3390/quat6030044) and Sirocko et al., 2022 (doi:10.1038/s41598-022-22464-x)), Dehner infilled maar (Sirocko et al., 2013, doi:10.1016/j.quascirev.2012.09.011), and Hoher List infilled maar (Sirocko et al., 2005 doi:10.1038/nature03905) to form the ELSA-23-Pollen-Stack covering the past 132,000 years. The pollen stack is complemented by a record of macroremains from Jungferweiher.

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