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As peatlands are a major terrestrial sink in the global carbon cycle, gaining an understanding of their development and changes throughout time is essential in order to predict their future carbon budget and potentially mitigate the adverse outcomes of climate change. With this aim to understand peat development, many studies have investigated the paleoecological dynamics by analyzing various proxies, including pollen, macrofossil, elemental, and biomarker analyses. However, as each of these proxies is known to have its own benefits and limitations, examining them in parallel allows for a deeper understanding of these paleoecological dynamics at the peatland and a systematic comparison of the power of these individual proxies. In this study, we therefore analyzed peat cores from a peatland in Germany (Beerberg, Thuringia) to (a) characterize the vegetation dynamics over the course of the peatland development during the late Holocene and (b) evaluate to what extent the inclusion of multiple proxies, specifically pollen, plant macrofossils, and biomarkers, contributes to a deeper understanding of those dynamics and interaction among factors. We found that, despite a major shift in the regional forest composition from primarily beech to spruce as well as many indicators of human impact in the region, the local plant population in the Beerberg area remained stable over time following the initial phase of peatland development up until the last couple of centuries. Therefore, little variation could be derived from the paleobotanical data alone. The combination of pollen and macrofossil analyses with the elemental and biomarker analyses enabled further understanding of the site development as these proxies added valuable additional information, including the occurrence of climatic variations, such as the Little Ice Age, and more recent disturbances, such as drainage. [ABSTRACT FROM AUTHOR]

This study investigated the history of the development of six, paleo-lakes, which are at present filled with sediments, in a dune area in Central Poland, based on multiproxy paleoecological analyses and accelerator mass spectrometry radiocarbon dating. The aims of the paleoecological studies were: i) to determine the initial age of lakes development, ii) to reconstruct the local and regional plant succession, as well as iii) to reconstruct the environmental conditions during the initial stage of the development of lakes and peatlands. The obtained results indicated that: the former lakes in dune depressions were developed during the Bølling and Allerød when sparse vegetation allowed strong aeolian activity. Climate warming in Bølling led to the development of a denser plant cover, inhibition of sand transportation and the formation of mid-dune reservoirs with the accumulation of organic sediments. As indicated by 14C dating, mid-dunes basins were formed between 14 686 ± 60 cal. yr BP and 13 421 ± 60 cal. yr BP. The results of the paleobotanical analysis suggested that the reservoirs were shallow, oligo-mesotrophic, inhabited by pioneer calcicole vascular plant species such as: Chara sp., Hippuris vulgaris, Potamogeton natans, Potamogeton fresii, Potamogeton alpinus and Potamogeton filiformis, and mosses such as: Pseudocalliergon trifarium, Calliergon sp. and Calliergonella cordifolium. The area next to the reservoirs was covered with sparse pine forests combined with birch, which is typical of the Late Glacial period. The open areas were dominated by psammophilic and steppe vegetation, including Poaceae, Artemisia and Hippophae rhamnoides. Geochemical analysis revealed that Ca2+ and Fe3+ were in high concentrations, which could have influenced the presence of taxa preferring soil with high Ca2+ content. The accumulation of calcium in sediments confirms that the reservoirs were fed by groundwater originating from the progressive degradation of permafrost associated with thermal changes. [ABSTRACT FROM AUTHOR]

Sedimentary charcoal records are widely used to reconstruct regional changes in fire regimes through time in the geological past. Existing global compilations are not geographically comprehensive and do not provide consistent metadata for all sites. Furthermore, the age models provided for these records are not harmonised and many are based on older calibrations of the radiocarbon ages. These issues limit the use of existing compilations for research into past fire regimes. Here, we present an expanded database of charcoal records, accompanied by new age models based on recalibration of radiocarbon ages using INTCAL2020 and Bayesian age-modelling software. We document the structure and contents of the database, the construction of the age models, and the quality control measures applied. We also record the expansion of geographical coverage relative to previous charcoal compilations and the expansion of metadata that can be used to inform analyses. This first version of the Reading Palaeofire Database contains 1681 records (entities) from 1477 sites worldwide. The database (DOI: 10.17864/1947.319) is available from https://researchdata.reading.ac.uk/id/eprint/319. [ABSTRACT FROM AUTHOR]

This article presents a reconstruction of Late Holocene vegetation changes within the lower montane forest zone in the Beskid Wyspowy Mountains (Western Carpathians, Central Europe). Pollen, non-pollen palynomorphs, loss on ignition, and microscopic charcoal analyses were applied to a profile collected from the deposits of the rich fen which developed in the landslide depression. The results reveal that during the period between ca. 4800 ± 70 and 4160 ± 60 cal. BP, Picea abies dominated in the local forests. Between ca. 4800 ± 70 and 4660 ± 60 cal. BP, Acer was an important component in local woodlands, which distinguishes the study site from others in the Western Carpathians. At ca. 4100 ± 60 cal. BP, forests dominated by Abies alba and Fagus sylvatica expanded. Nowadays, this type of vegetation is characteristic of the lower montane zone in the Polish Western Carpathians. This expansion was probably a consequence of environmental disturbances related to the cold and wet '4.2 ka BP' event. The spread of these forests was preceded by a short episode of expansion of Tilia (Tilia cordata and/or Tilia platyphyllos) which was a very local event. The area of the Beskid Wyspowy Mountains provided suitable habitats for the occurrence of T. baccata, which has not been recorded in pollen data spanning the Middle and beginning of the Late Holocene from this mountain range. A significant increase in the percentages of Kretzschmaria deusta, a parasitic fungus, reveals that A. alba–F. sylvatica forests provided an optimal habitat for such species during the period from 4070 ± 60 to 47 cal. BP. Since ca. 2640 ± 110 cal. BP, pollen of pioneer trees, such as Pinus sylvestris and Betula, as well as human activity indicators (Cerealia type and Plantago lanceolata) have become more frequent. Nonetheless, it is highly probable that this section of deposits also includes the presence of one or more sedimentary gaps. [ABSTRACT FROM AUTHOR]