Изменения окружающей среды в позднеледниковье и голоцене на юго-востоке Беларуси

Communicated by Academician Aleksey V. MatveevThe reconstruction of environmental changes in the southeast of Belarus during the last 14700 cal. BP is based on the results of palynological, radiocarbon, isotope and lithological studies of Lake Staroje deposits. Climatic fluctuations, fires and human activities played a significant role in the transformation of the vegetation cover. The beginning of the lacustrine sedimentation was dated circa 16000 cal. BP. The intensification of erosion processes on the water catchment area was marked by an increase in the mineral material flow into the lake. These events have a positive correlation with the climate cooling and humidity phases in the Late Glacial and Early Holocene, and in the Late Holocene with anthropogenic impact stages. The traces of the episodic human activity were dated to 5800 cal. BP, while the expansion of farming and pasturing areas began at 3000 cal. BP Currently the consequences of human activities (including drainage of bogs) are reflected in the treeless landscapes adjacent to the lake.Представлено академиком А. В. МатвеевымРеконструкция изменений окружающей среды на юго-востоке Беларуси в течение последних 14,7 тыс. кал. л. н. основана на результатах палинологических, радиоуглеродных, изотопных и литологических исследований отложений оз. Старое. Климатические колебания, пожары и деятельность человека играли значительную роль в преобразовании растительного покрова. Начало озерного седиментогенеза датируется около 16,0 тыс. кал. л. н. Усиление эрозионных процессов на водосборе было отмечено повышенным поступлением минерального материала в озеро. Эти события в позднеледниковье и раннем голоцене имеют положительную корреляцию с фазами похолодания и увлажнения климата, а в позднем голоцене с этапами антропогенного воздействия. Следы эпизодической деятельности человека установлены с ~5,8 тыс. кал. л. н., а начало земледелия и расширение пастбищных площадей с 3,0 тыс. кал. л. н. В настоящее время последствия хозяйственной деятельности человека (включая осушение болот) иллюстрируют безлесные ландшафты, прилегающие к озеру

European pollen-based REVEALS land-cover reconstructions for the Holocene: methodology, mapping and potentials

Quantitative reconstructions of past land cover are necessary to determine the processes involved in climate–human–land-cover interactions. We present the first temporally continuous and most spatially extensive pollen-based land-cover reconstruction for Europe over the Holocene (last 11 700 cal yr BP). We describe how vegetation cover has been quantified from pollen records at a 1∘ × 1∘ spatial scale using the “Regional Estimates of VEgetation Abundance from Large Sites” (REVEALS) model. REVEALS calculates estimates of past regional vegetation cover in proportions or percentages. REVEALS has been applied to 1128 pollen records across Europe and part of the eastern Mediterranean–Black Sea–Caspian corridor (30–75∘ N, 25∘ W–50∘ E) to reconstruct the percentage cover of 31 plant taxa assigned to 12 plant functional types (PFTs) and 3 land-cover types (LCTs). A new synthesis of relative pollen productivities (RPPs) for European plant taxa was performed for this reconstruction. It includes multiple RPP values (≥2 values) for 39 taxa and single values for 15 taxa (total of 54 taxa). To illustrate this, we present distribution maps for five taxa (Calluna vulgaris, Cerealia type (t)., Picea abies, deciduous Quercus t. and evergreen Quercus t.) and three land-cover types (open land, OL; evergreen trees, ETs; and summer-green trees, STs) for eight selected time windows. The reliability of the REVEALS reconstructions and issues related to the interpretation of the results in terms of landscape openness and human-induced vegetation change are discussed. This is followed by a review of the current use of this reconstruction and its future potential utility and development. REVEALS data quality are primarily determined by pollen count data (pollen count and sample, pollen identification, and chronology) and site type and number (lake or bog, large or small, one site vs. multiple sites) used for REVEALS analysis (for each grid cell). A large number of sites with high-quality pollen count data will produce more reliable land-cover estimates with lower standard errors compared to a low number of sites with lower-quality pollen count data. The REVEALS data presented here can be downloaded from https://doi.org/10.1594/PANGAEA.937075 (Fyfe et al., 2022)

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° × 1°) 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