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Spatial vegetation patterns potentially reflect coeval continental climate variations which are also impacted by palaeogeographical settings. Plant functional types (PFTs) and their distribution, frequently applied in ecological studies and biome modelling, serve as a tool for reconstructing palaeovegetation units and ultimately tracing palaeoecological/climate gradients. Earlier quantitative studies focusing on distribution patterns of PFTs and designed to put forward data‐model comparisons were carried out on well‐dated Middle and Late Miocene floras. Moreover, the PFT approach has been successfully applied to reconstruct Eocene vegetation patterns in several time slices at a global scale as well as in regional vegetation reconstructions throughout the Cenozoic. In the current study, a PFT approach with 41 different classes is applied on Rupelian and Chattian fossil floras of Europe and western Asia to infer spatial vegetation differences across the study area. A comprehensive palaeobotanical record including ~163 macro‐ (leaves, fruits and seeds) and microfloras was compiled. The floristic components of these palaeofloras are translated to PFTs including herbaceous to arboreal classes. The PFTs are defined using traits and climatic thresholds of key taxa, and comprise species assigned by morphological and phenological features with respect to the related ecosystem. Diversity values of each PFT are calculated for the fossil floras and spatial gradients over western Eurasia are investigated for the Rupelian and Chattian. PFT diversity maps and transects for both time slices reveal basic patterns of the vegetational structure at the continental scale. It is shown that in both time slices studied tropical and broadleaved evergreen PFTs were more diverse in the West and at lower latitudes. Consistently with the global climate evolution as known from marine archives and regional continental records their level was higher in the Rupelian compared to the Chattian. All over low diversities of xeric PFTs coincide with the previously assumed dominance of humid climate conditions in western Eurasia throughout the Oligocene, however, the reconstructed spatial gradients suggest somewhat drier conditions to the southwest and southeast of the study area. [ABSTRACT FROM AUTHOR]

Cenozoic vegetation gradients in the mid- and higher latitudes of Central Eurasia are studied based on a total of 22 mega- (fruits and seeds, leaves) and 20 microfloras (pollen and spores) compiled from literature. Vegetation is interpreted at the level of plants functional types (PFTs) using a system including 26 classes and an aquatic functional type. The obtained ecospectra showing diversity of PFTs are interpreted in three time slices, namely the early Oligocene, early Miocene and late Pliocene/early Pleistocene. Our results confirm the presence of diverse mixed forests (Turgai type) in the study area throughout the late Paleogene and early Neogene, partly, raised diversity of herbaceous components, especially of dry herbs, and the presence of xeric shrub PFTs points to more open plant cover. The late Pliocene/early Pleistocene spectra from the central and southern latitudinal zones of the study area confirm the existence of open landscapes in general, but partly have a considerable arboreal diversity excluding the presence of mere steppe. Ecospectra obtained from the diversity of functional types have a characteristic representativeness depending on the organ types considered in each case, and therefore have a delimited comparability. Our results show that PFT diversities obtained from microfloras are most suitable in estimating the openness of landscape and in representing zonal biomes in general. The vegetational patterns reconstructed based on the ecospectra of fossil floras basically support the results obtained from previous palaeoclimate reconstructions evidencing cooling and drying of the continental interior of Eurasia throughout the later Neogene. Moreover, the PFT approach is proven more sensitive to identify seasonal drought when compared to other, taxonomy based climate reconstruction methods. Moreover, a first attempt is made to quantify latitudinal temperature gradients for the study area. Data indicate that the Oligocene and early Miocene gradients where shallow and almost identical while the late Pliocene/early Pleistocene gradient was intermediate between the earlier Neogene and the modern one. [ABSTRACT FROM AUTHOR]

Abstract: Recent studies in the frame of the NECLIME (Neogene Climate Evolution in Eurasia) network provide a comprehensive inventory of continental palaeoclimate data for various time slices reconstructed from the palaeobotanical record. The integrative analysis of spatial gradients and patterns observed from the proxy data, together with data obtained from numeric modelling studies considerably improved our knowledge about the functioning of the climate system in the Cenozoic. When compared to the present an overall warmer, more humid climate existed. Cenozoic climates are characterized by warm high latitudes, shallow latitudinal and longitudinal gradients and wet continental interiors while concentration of greenhouse gases was about at the present-day level or considerably higher. Thus, these past climates potentially are valuable to better understand future climate change because they allow empirical access to climate situations that do not or not yet exist today. In the present study, continental climate data calculated from micro- and macrofloras using the Coexistence Approach are analysed in order to compare past gradients and patterns and their anomalies relative to present-day conditions with future climate change scenarios. For the case study, three time intervals are selected: The Mid-Eocene represents a very warm period of the Cenozoic exemplifying greenhouse conditions with high atmospheric CO2 of over 1.100 ppmv. The Mid-Miocene is known as outstanding warm time interval as well. The concentration of greenhouse gases is still controversially discussed, but was certainly below the Eocene level. A third interval selected, the Tortonian, represents a time-span of subsequent cooling with the beginning of Arctic glaciation. For this period, a pre-industrial CO2 level is assumed. It is shown that the study of past climate patterns provides important clues when evaluating modelling results for future scenarios. Anomalies predicted under global warming partly coincide with the palaeoclimate data sets. As an example for greenhouse conditions, the Mid-Eocene data also show a strong warming of the high latitudes and a significant positive anomaly of winter temperatures in the continental interior as in the model study for the future scenario. However, for the Tortonian where a pre-industrial CO2 can be assumed data show the best agreement with predicted patterns. [Copyright &y& Elsevier]