Pollen analysis of the peat in a small mire on the northern slope of the Alborz Mountains (550 m a.s.l.) in the Central Caspian forests of Iran reveals changes in forest and wetland vegetation during the last millennium. A forest, principally of Alnus and Carpinus occurred over almost the whole period. Quercus, Ulmus and Parrotia were less common, while Fagus, Pterocarya, Acer and Diospyros fluctuated as a probable result of human interference and/or climatic change. Two phases of clay deposition in the mire can be dated to the `Mediaeval Climatic Anomaly' (AD 1100) and the beginning of the `Little Ice Age' (AD 1560—1600). Although human activity seems to have persisted in the region during the whole of the past millennium, increased NAP values point to intensified human interference since the beginning of the nineteenth century.

Aim To evaluate the biomization technique for reconstructing past vegetation in the Eastern Mediterranean–Black Sea–Caspian‐Corridor using an extensive modern pollen data set and comparing reconstructions to potential vegetation and observed land cover data. Location The region between 28–48°N and 22–62°E. Methods We apply the biomization technique to 1,387 modern pollen samples, representing 1,107 entities, to reconstruct the distribution of 13 broad vegetation categories (biomes). We assess the results using estimates of potential natural vegetation from the European Vegetation Map and the Physico‐Geographic Atlas of the World. We test whether anthropogenic disturbance affects reconstruction quality using land use information from the Global Land Cover data set. Results The biomization scheme successfully predicts the broadscale patterns of vegetation across the region, including changes with elevation. The technique discriminates deserts from shrublands, the prevalence of woodlands in moister lowland sites, and the presence of temperate and mixed forests at higher elevations. Quantitative assessment of the reconstructions is less satisfactory: the biome is predicted correctly at 44% of the sites in Europe and 33% of the sites overall. The low success rate is not a reflection of anthropogenic impacts: only 33% of the samples are correctly assigned after the removal of sites in anthropogenically altered environments. Open vegetation is less successfully predicted (33%) than forest types (73%), reflecting the under‐representation of herbaceous taxa in pollen assemblages and the impact of long‐distance pollen transport into open environments. Samples from small basins (<1 km2) are more likely to be reconstructed accurately, with 58% of the sites in Europe and 66% of all sites correctly predicted, probably because they sample an appropriate pollen source area to reflect regional vegetation patterns in relatively heterogeneous landscapes. While methodological biases exist, the low confidence of the quantitative comparisons should not be over‐emphasized because the target maps themselves are not accurate representations of vegetation patterns in this region. Main Conclusions The biomization scheme yields reasonable reconstructions of the broadscale vegetation patterns in the Eastern Mediterranean–Black Sea–Caspian‐Corridor, particularly if appropriate‐sized sampling sites are used. Our results indicate biomization could be used to reconstruct changing patterns of vegetation in response to past climate changes in this region.

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New pollen evidence from two sites in South-Central Zagros (Lake Maharlou), Southwestern Iran, and Sahand Mountains (Lake Almalou), Northwestern Iran, provide evidence for the emergence of tree cultivation in Southwestern Iran since the 3rd and 2nd millennia BC and upland agricultural activities in Northwestern Iran since 5th to 3rd centuries BC. Juglans cf. regia could have been cultivated fi rstly at ~2500 BC and became more extensively cultivated since ~1200 BC. Platanus cf. orientalis was also probably cultivated very early at ~1900 BC during the Middle Elamite period (2800-550 BC) and became more widely cultivated from ~1200 BC along with Juglans. The latter arboricultural events could have resulted from the establishment of great urban civilizations in Southwestern Iran. The rise of the Persian Empires seems to have been associated with a large-scale agricultural revolution over the Iranian Plateau. During the Persian Achaemenid Empire (550-330 BC) tree cultivation expanded in the Lake Maharlou area and agricultural practices expanded into upland areas in Lake Almalou area probably due to socioeconomic stability and the development of water exploitation and irrigation techniques. The Parthian (250 BC-225 AD) and Sassanian (224-642 AD) periods were also associated with tree cultivation practices in Lake Maharlou area but to a lower extent comparing to the Achaemenid period. In the Lake Almalou area, the Parthian period saw no spectacular agricultural event at least partly due to political and socioeconomic instability caused by confl icts with Romans over Armenia. The socioeconomic stability and further development in agricultural techniques during the Sassanian Empire could, however, favor again the large-scale tree cultivation practices in Northwestern Iran. The Post-Islamic period is characterized by reduced agricultural activities in the Iranian Plateau most probably due to political instability caused by numerous invasions by Arabs, Turks and Mongols. The last signifi cant agricultural event recorded in the Lake Almalou pollen record is the appearance of Ricinus communis cultivated since the beginning of the Safavid Empire (1501-1722 AD). Résumé : De nouvelles données polliniques provenant de deux sites dans les montagnes du Zagros (lac Maharlou, Sud-Ouest l'Iran) et de Sahand (lac Almalou, Nord-Ouest de l'Iran), apportent des indications sur l'émergence de l'arboriculture dans le Sud-Ouest iranien depuis les III e et II e millénaires av. J.-C., et sur les pratiques agricoles dans les hautes terres du Nord-Ouest iranien du V e au III e siècles av. J.-C. Juglans cf. regia fut probablement cultivé dès 2500 av. J.-C., puis plus extensivement à partir de 1200 av. J.-C. environ. Platanus cf. orientalis fut probablement cultivé précocement, vers 1900 av. J.-C., au cours de la période élamite moyenne (2800-550 av. J.-C.), et il devint plus largement cultivé à partir de ca. 1200 av. J.-C, parallèlement à la culture de Juglans. Ces innovations agricoles ont pu résulter du développement des grandes civilisations ...