Environment and man around Lakes Duba and Pelesa, SE Lithuania, during the Late Glacial and Holocene

Interdisciplinary investigations (pollen and diatom analysis, 14C dating and geological-geomorphological and archaeological data) around Lakes Duba and Pelesa, in SE Lithuania, have elucidated the environmental history and human impact throughout the Late Glacial and Holocene. Aerial photograph interpretations indicate that both lakes are residual basins of one Post-Glacial palaeolake outside the morainic relief of the Nemunas (Weichselian) Glaciation. Pollen assemblages from lacustrine deposits date back to the Older Dryas (Lake Duba) and Alleröd (Lake Pelesa) and cover all chronozones of the Post-Glacial. Diatom analysis has illustrated the palaeoecological conditions in the lakes and helped reconstruct successive water levels throughout the last 12300 radiocarbon years. Diatom abundance and the distribution of the planktonic, benthic and epiphytic species suggest a lowering of Lake Duba and Lake Pelesa at (e.g.) 11900-10900 14C BP, (e.g.) 10000-8100 14C BP and (e.g.) 3700-2500 14C BP. Pollen data suggest that the earliest signs of human impact and local forest clearances data from about (e.g.) 8400-8300 14C BP. The first record of cereal pollen in sediments dates from earlier than (e.g.) 6000 14C BP. Therefore, agriculture was introduced into the area not earlier than the second half of the Midle Neolithic, at about (e.g.) 5000-4400 14C BP. Continous indications of agriculture and progressive clearing of woodland is consistent with the increasing role of a farming economy during the Bronze Age. Since the 1800-1900 14C BP formation of an open canopy, increasing soil erosion and changes in vegetation emphasize the remarkable human impact on the environment

Testing the Effect of Relative Pollen Productivity on the REVEALS Model: A Validated Reconstruction of Europe-Wide Holocene Vegetation

Reliable quantitative vegetation reconstructions for Europe during the Holocene are crucial to improving our understanding of landscape dynamics, making it possible to assess the past effects of environmental variables and land-use change on ecosystems and biodiversity, and mitigating their effects in the future. We present here the most spatially extensive and temporally continuous pollen-based reconstructions of plant cover in Europe (at a spatial resolution of 1 degrees x 1 degrees) over the Holocene (last 11.7 ka BP) using the 'Regional Estimates of VEgetation Abundance from Large Sites' (REVEALS) model. This study has three main aims. First, to present the most accurate and reliable generation of REVEALS reconstructions across Europe so far. This has been achieved by including a larger number of pollen records compared to former analyses, in particular from the Mediterranean area. Second, to discuss methodological issues in the quantification of past land cover by using alternative datasets of relative pollen productivities (RPPs), one of the key input parameters of REVEALS, to test model sensitivity. Finally, to validate our reconstructions with the global forest change dataset. The results suggest that the RPPs.st1 (31 taxa) dataset is best suited to producing regional vegetation cover estimates for Europe. These reconstructions offer a long-term perspective providing unique possibilities to explore spatial-temporal changes in past land cover and biodiversity