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Here we describe the LegacyClimate 1.0, a dataset of the reconstruction of mean July temperature (TJuly), mean annual temperature (Tann), and annual precipitation (Pann) from 2594 fossil pollen records from the Northern Hemisphere spanning the entire Holocene with some records reaching back to the Last Glacial. Two reconstruction methods, the Modern Analogue Technique (MAT) and Weighted-Averaging Partial-Least Squares regression (WA-PLS) reveal similar results regarding spatial and temporal patterns. To reduce the impact of precipitation on temperature reconstruction and vice versa, we also provide reconstructions using tailored modern pollen data limiting the range of the corresponding other climate variables. We assess the reliability of the reconstructions using information from the spatial distributions of the root-mean squared error of prediction and reconstruction significance tests. The dataset is beneficial for climate proxy synthesis studies and to evaluate the output of climate models and thus help to improve the models themselves. We provide our compilation of reconstructed TJuly, Tann, and Pann as open-access datasets at PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.930512; Herzschuh et al., 2021). R code for the reconstructions is provided at Zenodo (https://doi.org/10.5281/zenodo.5910989; Herzschuh et al., 2022), including harmonized open-access modern and fossil datasets used for the reconstructions, so that customized reconstructions can be easily established. [ABSTRACT FROM AUTHOR]

Methodological papers advise to collect moss surface samples either at the beginning or at the end of the flowering season. In reality, such collections occur often within the flowering season for purposes of vegetation description or because of accessibility of remote study areas. Here we test whether the season of moss surface sample collection has an influence on pollen spectra. Ten moss/litter samples were collected in different habitats of the natural reserve 'Spasskaya Gora' (Perm region, Russia) in July and September from the same locations exactly. The results show that pollen assemblages reflect well the present dominant vegetation of Pinus-Betula-forests and grasslands and demonstrate differences between open and forested areas as well as between abandoned fodder meadows and semi-natural hay meadows in use. Paired t-tests and Wilcoxon tests demonstrate that the dominant pollen taxa Pinus diploxylon-type, Betula and Poaceae as well as the rarefied number of pollen taxa do not differ significantly between seasons, while values of Artemisia are significantly higher in September. A significant decrease in pollen concentration in September indicates the importance of washing-out of pollen by precipitation. PCA results demonstrate the similarity of the pollen spectra between the seasons. Based on our results, we conclude that the season of surface sample collection does not significantly influence the pollen assemblages and appropriate field studies can be carried out in summer during the flowering season. However, we strongly recommend to collect bulk samples of mosses with basal parts and/or litter with surface soils in order to ensure representation of the average pollen signal for the previous years and to dilute local extremes in the pollen deposition. [ABSTRACT FROM AUTHOR]

Recent revision of the Pleistocene glaciation boundaries in northern Eurasia has encouraged the search for nonglacial geological records of the environmental history of northern West Siberia. We studied an alluvial paleosol-sedimentary sequence of the high terrace of the Vakh River (middle Ob basin) to extract the indicators of environmental change since Marine Oxygen Isotope Stage (MIS) 6. Two levels of the buried paleosols are attributed to MIS 5 and MIS 3, as evidenced by U/Th and radiocarbon dates. Palynological and pedogenetic characteristics of the lower pedocomplex recorded the climate fluctuations during MIS 5, from the Picea-Larix taiga environment during MIS 5e to the establishment of the tundra-steppe environment due to the cooling of MIS 5d or MIS 5b and partial recovery of boreal forests with Picea and Pinus in MIS 5c or MIS 5a. The upper paleosol level shows signs of cryogenic hydromorphic pedogenesis corresponding to the tundra landscape, with permafrost during MIS 3. Boulders incorporated in a laminated alluvial deposit between the paleosols are dropstones brought from the Enisei valley by ice rafting during the cold MIS 4. An abundance of eolian morphostructures on quartz grains from the sediments that overly the upper paleosol suggests a cold, dry, and windy environment during the MIS 2 cryochron. [ABSTRACT FROM AUTHOR]

Today, the East European forest-steppe is an agricultural landscape with very few remains of its former natural vegetation. The history of the transformation from natural vegetation to a human-made landscape in the area of Sudzha (Kursk region, Russia) is studied here. We compare the off-site pollen record Sudzha with three on-site pollen records obtained from the archaeological site Kurilovka-2. The sediment core Sudzha covering the last 2,500 years was taken from an oxbow lake in an area with archaeological sites of the early Slavonic period (3rd–8th centuries ce). The Sudzha pollen record indicates dominance of broadleaf forests and meadow steppes in the area from 2,500 to 200 cal year bp with two major settlement phases one between ~ 2,000 and 1,600 cal year bp (~ 50 bce to 350 ce) and the other between 1,100 and 600 cal year bp (850 and 1350 ce) followed by a total deforestation and transformation to an agricultural landscape over the last 200–300 years. Similar changes in the last 300–400 years are indicated by the three on-site pollen records. It is noteworthy, however, that the record Sudzha does not provide an intensive signal of human impact during the 5th–8th centuries ce. This points to a quite restricted spatial influence of the Early Slavonic settlements on the vegetation, leading to a relatively low contribution of palynological anthropogenic indicators to the regional pollen rain signal. [ABSTRACT FROM AUTHOR]

Lake Ladoga hosts preglacial sediments, although the Eurasian ice sheet overrode the area during the LGM. These sediments were first discovered by a seismic survey and are investigated using a 22.75‐m‐long core. Its upper 13.30 m comprise Holocene and Lateglacial sediments separated from the lower 11.45 m of preglacial sediments by a hiatus. They consist of highly terrigenous lacustrine sediments, which according to OSL dating, were deposited during an early stage of the last ice age (MIS 5). The palynological data allow a first reconstruction of the Early Weichselian environmental history for northwestern Russia. Birch and alder forests with broad‐leaved taxa dominated during MIS 5d (c. 118–113 ka), suggesting a climate more favourable than in the Holocene. A high content of well‐sorted sands and poorly preserved palynomorphs indicates a shallow‐water environment at least temporarily. More fine‐grained sediments and better preserved organic remains suggest deeper water environments at the core location during MIS 5c (c. 113–88 ka). Pine and spruce became dominant, while broad‐leaved taxa started to disappear, especially after c. 90 ka, pointing to a gradual climate cooling. An increase in open herb‐dominated habitats at the beginning of MIS 5b (c. 88–86 ka) reflects a colder and dryer climate. However, later (c. 86–82 ka) pine and spruce again became more common. Birch and alder forests dominated in the area c. 82–80 ka (beginning of MIS 5a). Although open treeless habitats also became more common at this time, a slight increase in hazel may point to somewhat warmer climate conditions coinciding with the beginning of MIS 5a. The studied sediments also contain numerous remains of freshwater algae and cysts of marine and brackish‐water dinoflagellates and acritarchs documenting that the present lake basin was part of a brackish‐water basin during the Early Weichselian, probably as a gulf of the Pre‐Baltic Sea. [ABSTRACT FROM AUTHOR]

The first Holocene record of the freshwater ascomycete Megalohypha aqua - dulces from the sediment core Kongor (NE Iran) is presented here. Based on the similarity of the spore morphology with the fossil form genus Fusiformisporites , we establish a link between extant and fossil taxa. Comparative analysis of morphological characteristics of fossil spores of Fusiformisporites indicates that several different fungal groups might be included in this form genus. At least five species of Fusiformisporites share similar morphology with spores of Megalohypha aqua - dulces : Fusiformisporites annafrancescae , Fusiformisporites crabbii , Fusiformisporites keralensis , Fusiformisporites paucistriatus , and Fusiformisporites pseudocrabbii . Based on Fusiformisporites , the evolution of Megalohypha aqua - dulces can be traced to the late Cretaceous, corresponding with diversification of the flowering plants and pointing to a co-evolution of both groups. Megalohypha aqua - dulces has a tropical to subtropical distribution but also occurs in the semi-arid steppe environments of Kongor together with other freshwater fungal genera such as Xylomyces , Dictyosporium , and Sporoschisma , which spores we describe here. The ecological requirements of Megalohypha indicate that its spores can be used for the palaeoecological sign of dead submerged wood as well as of tropical to subtropical conditions. [ABSTRACT FROM AUTHOR]

Abstract: This multiproxy study on SE Black Sea sediments provides the first detailed reconstruction of vegetation and environmental history of Northern Anatolia between 134 and 119ka. Here, the glacial–interglacial transition is characterized by several short-lived alternating cold and warm events preceding a meltwater pulse (~130.4–131.7ka). The latter is reconstructed as a cold arid period correlated to Heinrich event 11. The initial warming is evidenced at ~130.4ka by increased primary productivity in the Black Sea, disappearance of ice-rafted detritus, and spreading of oaks in Anatolia. A Younger Dryas-type event is not identifiable. The Eemian vegetation succession corresponds to the main climatic phases in Europe: i) the Quercus–Juniperus phase (128.7–126.4ka) indicates a dry continental climate; ii) the Ostrya–Corylus–Quercus–Carpinus phase (126.4–122.9ka) suggests warm summers, mild winters, and high year-round precipitation; iii) the Fagus–Carpinus phase (122.9–119.5ka) indicates cooling and high precipitation; and iv) increasing Pinus at ~121ka marks the onset of cooler/drier conditions. Generally, pollen reconstructions suggest altitudinal/latitudinal migrations of vegetation belts in Northern Anatolia during the Eemian caused by increased transport of moisture. The evidence for the wide distribution of Fagus around the Black Sea contrasts with the European records and is likely related to climatic and genetic factors. [Copyright &y& Elsevier]

Abstract: Sediments from the Black Sea, a region historically dominated by forests and steppe landscapes, are a valuable source of detailed information on the changes in regional terrestrial and aquatic environments at decadal to millennial scales. Here we present multi-proxy environmental records (pollen, dinoflagellate cysts, Ca, Ti and oxygen isotope data) from the uppermost 305cm of the core 22-GC3 (42°13.53′N, 36°29.55′E) collected from a water depth of 838m in the southern part of the Black Sea in 2007. The records span the last ~18kyr (all ages are given in cal kyr BP). The pollen data reveal the dominance of the Artemisia-steppe in the region, suggesting rather dry/cold environments ~18–14.5kyr BP. Warming/humidity increase during melt-water pulses (~16.1–14.5kyr BP), indicated by δ 18 O records from the 22-GC3 core sediment and from the Sofular Cave stalagmite, is expressed in more negative δ 13 C values from the Sofular Cave, usually interpreted as the spreading of C3 plants. The records representing the interstadial complex (~14.5–12.9kyr BP) show an increase in temperature and moisture, indicated by forest development, increased primary productivity and reduced surface run-off, whereas the switch from primary terrigenous to primary authigenic Ca origin occurs ~500yr later. The Younger Dryas cooling is clearly demonstrated by more negative δ13C values from the Sofular Cave and a reduction of pines. The early Holocene (11.7–8.5kyr BP) interval reveals relatively dry conditions compared to the mostly moist and warm middle Holocene (8.5–5kyr BP), which is characterized by the establishment of the species-rich warm mixed and temperate deciduous forests in the low elevation belt, temperate deciduous beech-hornbeam forests in the middle and cool conifer forest in upper mountain belt. The border between the early and middle Holocene in the vegetation records coincides with the opening of the Mediterranean corridor at ~8.3kyr BP, as indicated by a marked change in the dinocyst assemblages and in the sediment lithology. Changes in the pollen assemblages indicate a reduction in forest cover after ~5kyr BP, which was likely caused by increased anthropogenic pressure on the regional vegetation. [Copyright &y& Elsevier]