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The synthetic analysis of several pollen records from sub-Mediterranean lowland Pre-Pyrenean regions evidences expansion of forests during the Early Holocene in Northeastern Iberia and the establishment of dense deciduous broadleaf forests during the Holocene Climate Optimum. Pollen records show the broadleaf deciduous forests resilience against cooling phases during the Mid-Holocene period, with slight regressions of oak woodlands and expansion of conifers or xerophytic taxa contemporary to some cooling episodes (i.e. 8.2 and 7.2 kyr cal. BP). Major vegetation changes influenced by climate change occurred in the transition to the Late Holocene, in terms of the start of a succession from broadleaf deciduous forests to evergreen sclerophyllous woodlands. The lack of evidence of previous occupation seems to support the Neolithisation of the NE Iberian Peninsula as a result of a process of migration of farming populations to uninhabited or sparsely inhabited territories. In that context, remarkable changes in vegetation were recorded from 7.3 kyr cal. BP onwards in the Lake Banyoles area, where the establishment of permanent farming settlements caused the deforestation of oak woodlands. In La Garrotxa region, short deforestation episodes affecting broadleaf deciduous forests, together with expansion of grasslands and presence of Cerealia-t were documented in the period 7.4–6.0 kyr cal. BP. Finally, in the coastal area, where less evidence of Early Neolithic occupations is recorded, evidence of Neolithic impact is reflected in the presence of Cerealia-t in 6.5–6.2 kyr cal. BP, but no strong human transformation of landscape was carried out until more recent chronologies. [ABSTRACT FROM AUTHOR]

Several taphonomic factors influence the composition of the palynological record especially in archaeological deposits, where human activities alter the representation of taxa. Spatial analysis by a taphonomic approach to the distribution of pollen and non-pollen palynomorphs (NPP) provides useful information about intra-site spaces and environments in the Early Neolithic lakeside settlement of La Draga (Banyoles, NE Iberia). The spatial correlation of algae, lakeshore and aquatic plants and herbs with an economic value, together with eggs of intestinal parasites and spores of coprophilous fungi, evidence a humid and organic environment beneath a hut, where consumption waste is concentrated. In contrast, high values of arboreal pollen (AP) and spores of fungal indicators of soil erosion show a sub-aerial environment strongly altered by taphonomic processes in outside areas. Finally, the association of the highest values in Cerealia-t and the spatial distribution of grinding stones within Sector D identifies an area of cereal processing, proving the suitability of spatial analysis in archaeopalynology as a powerful tool for reconstructing activity areas within archaeological settlements. [ABSTRACT FROM AUTHOR]

Pollen and non-pollen palynomorphs (NPP) from the Early Neolithic settlement of La Draga have provided new palaeoenvironmental data concerning the establishment of the first farming societies in NE Iberian Peninsula. The analysis of samples from the archaeological profiles allowed the comprehension of several processes involved in the formation of this archaeological site and the reconstruction of environmental conditions in the different phases of occupation, in addition to obtaining new data about the ecological significance of NPP in archaeological levels. New NPP have been described, illustrated, and discussed. The first farming societies settled at La Draga in a humid and densely forested area, with the predominance of deciduous trees (deciduous Quercus and Corylus ) and Pinus and Abies in the surrounding mountains. Following their establishment at the site, abrupt changes in vegetation are recorded, in terms of deforestation of oak and riparian forests. Sedimentation dynamics involved in the formation of the archaeological site influenced the composition of the NPP spectra, reflected in the contraposition between waterlogged and subaerial layers, but especially, between organic peaty layers formed at local level and sediments transported by erosive processes in the layers belonging to the second phase of occupation. [ABSTRACT FROM AUTHOR]

• Geochemical and charcoal data show an interaction human- climate-fire interaction. • Archaeological data show information of burning practices during Late Mesolithic. • Human presence and fire gap episodes during the 8.2 ka event show the same dynamic. • Neolithic charcoal data show climate-human relation during landscape changes. Climate variability such as higher or lower temperatures, changing precipitation patterns, shifts in plant communities and other climate-related changes have particularly affected areas with Mediterranean-type climates. A multi-proxy analysis including pollen, sedimentary charcoal, mineralogy and Summed Probability Distributions (SPD) of archaeological 14C dates, allowed the reconstruction of landscape change, geomorphological evolution and fire history at the Laguna de Villena, in the southeastern Iberian Peninsula, during the Mesolithic-Neolithic transition. The Villena paleolake was sensitive to Early Holocene and Middle Holocene regional climatic variability that included several arid phases (around 8.2 ka cal BP, 6.8 ka cal BP and 5.9 ka cal BP) according to geochemical and pollen data. During this period, landscape dynamics show the degradation of oak forests and expansion of pyrophytic pine forests and shrublands, as well as open spaces predominated by grasses. The charcoal record shows a decreasing trend of biomass burned from 8.5 ka cal BP onwards, although fire peaks occurred recurrently during the Early and Middle Holocene. The most intense phase of fire activity was experienced in the last millennia of the Early Holocene, with five fire episodes from 9.1 to 8.4 ka cal BP, coinciding with a phase of higher archaeological evidence in the area. A decrease in archaeological evidence coincides with a gap in fire episodes during the Early Holocene-Middle Holocene transition, suggesting an effect of the abrupt 8.2 ka cal BP event on human activity and on landscape dynamics. After 8.0 ka cal BP, lowerer biomass burned is explained by the configuration of a more open landscape due to the combination of climate (increasing aridity) and increasing human activities in the region. The mineralogical and palynological data highlighted the interaction between human activities, climate and fire dynamics. The sedimentary charcoal record evidenced how most of the fire peaks did not occur in the context of dry episodes, as often assumed, deriving on an anthropogenic explanation related to Early and Late Mesolithic burning practices during a phase of higher archaeological evidence in the Villena paleolake surroundings. Afterwards, combined agropastoral activities from the Early Neolithic onwards and increasing aridity during the Middle Holocene maintained the forest clearances, in the context of fire episodes characterised by decreased biomass burned. This study shows how Middle Holocene palaeoecological records reflect complex histories blending climate and anthropogenic processes that derived in major landscape changes explaining the origin of current landscapes. [ABSTRACT FROM AUTHOR]

This paper focuses on high-resolution analysis of pollen and sedimentology and botanical macro-remains analysis in a core from Lake Banyoles (Girona, Spain). The core sequence comprises a high resolution mid-Holocene (ca. 8.9–3.35 cal ka BP) vegetation succession, and sedimentological, geochemical and geomorphological proxies are related to both climatic and anthropogenic causes. Deforestation processes affected natural vegetation development in the Early Neolithic (7.25–5.55 cal ka BP) and Late Neolithic (5.17–3.71 cal ka BP), in the context of broadleaf deciduous forest resilience against cooling and drying oscillations. Changes in sedimentation dynamics and in lake water level caused the emergence of dry land on the lake margin where riparian forest was established from 5.55 cal ka BP onwards. The data show that in the context of an increasing aridification process, Neolithic land-use played an important role in vegetation history and environmental evolution. [ABSTRACT FROM AUTHOR]