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Интеллектуальная Система Тематического Исследования НАукометрических данных |
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The present research aimed to assess Holocene woody cover densities and vegetation dynamics in the forest steppe zone of European Russia using analogue-based methods of quantity reconstructions and one of the innovative approaches, which combines modern and fossil pollen datasets with MODIS satellite images. The main steps of our study were follows: (1) creation the reference dataset consisting of 965 surface pollen spectra and associated satellite (MODIS)-based estimates of woody cover density, (2) checking the accuracy of regional woody cover reconstructions using the BMA approach applied to the reference modern dataset, and (3) application the method for reconstruction of vegetation disturbance in the key-region in the forest-steppe zone. The accuracy of regional woody cover reconstructions was tested by leave-one-out cross-validation (R2=0.57 and SEE= 10.8%). The study area locates in the central part of the East European Plain which includes the Upper Don River basin and its tributaries, the so-called Kulikovo Battlefield area. New pollen, plant macrofossil, micro-charcoal evidences and radiocarbon dates were revealed from “Podkosmovo” mire (N 53.67027 E 38.59055); these allow us to reconstruct the landscape and human activity for the time span ranging from the mid-Atlantic period to the present. The obtained results show that the high biodiversity of the forest-steppe area made the upper Don River basin very attractive for early human populations. Signals of anthropogenic changes in the vegetation and human-induced fires are clearly pronounced in the pollen and micro-charcoal records in the Neolithic and Bronze Ages, however human impact on plant cover was not significant until 2400 cal. yr. BP. Reconstructions of total woody cover show a good agreement with land-use history of the territory. An extensive agriculture during the periods of human occupation resulted in decrease in forest coverage, when the territory was abandoned forests recovered their areas. Large-scale landscape changes and the degradation of natural vegetation occurred in the medieval time and become conspicuous over the last two centuries. Application of the best-modern-analogue technique to pollen data from the key-region in the forest-steppe zone of European Russia demonstrated that the changes in regional woody cover are appeared as a good tool for reconstruction of anthropogenic disturbance in the prehistoric time.