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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]

The Pliocene Villarroya basin fill consists of lacustrine and alluvial deposits over 100 m thick. The lacustrine deposits, up to 30 m thick, comprise three sequences. The two lower sequences consist of profundal, laminated deposits formed by mostly terrigenous facies that are overlain by charophytic carbonates and varves. The uppermost, third sequence made up of massive bioturbated mudstones corresponds to a very shallow lacustrine–palustrine environment. Bulk mineralogy comprises carbonates, clay minerals, quartz and feldspars. The carbonates are: exogenic, biogenic calcite and biogenic aragonite. Biogenic calcite constitutes ostracod shells and charophyte stem encrustations, whereas aragonite forms gastropod shells and, in some varve intervals, charophyte encrustations. The clay minerals are illite, kaolinite, palygorskite, chlorite and paragonite, which are inherited from source rocks, and smectite and interstratified clays, which are probably formed in the soils of the source area. Variations in clay mineralogy reflect the interplay between the climate, tectonic rejuvenation and the paleogeography of the basin.The pollen assemblages indicate significant variations in climate: a first phase of varying climate was followed by cool-temperate and sub-humid phases that culminated in a temperate and dry episode, which is recorded in the lower part of the second lacustrine sequence. This was succeeded by a marked warm and humid episode, which may be correlated with the Mid-Pliocene warmth about 3.0 Ma and the subsequent cooling phase, which is recorded in the upper, third sequence.In the two lower sequences (profundal lacustrine deposits), ostracods indicate oligosaline to mesosaline waters with salinity variations and some warm and Na–Cl episodes. Molluscs are characterized by hydrobiids, suggesting a salinity stress. In the upper, palustrine deposits, the ostracods and aquatic mollusc assemblages indicate fresh, cold waters. Faunal records indicate that changes in salinity do not correlate with climate, suggesting phases of significant saline inputs to the lake which were recorded in the lower first sequence and in the upper part of the second sequence.The lacustrine sequence of Villarroya record pronounced variations in climate and in the lacustrine environment. However, there are no consistent relationships between the climate conditions inferred from the pollen data and the sedimentary record of the environmental changes, showing that other factors, especially tectonics, have exerted an influence on the paleoenvironmental evolution, and on the sedimentary record of the Pliocene Villarroya lake. [Copyright &y& Elsevier]

This paper assesses the landscape and management of firewood resources during the Holocene at La Garrotxa (Girona, NE Iberia), a middle mountain region (400-1600 m a.s.l.) located within a volcanic area in the Pre-Pyrenees. Anthracological and palynological data from archaeological sites and lacustrine and peat deposits in this area have been considered in an interdisciplinary approach to the landscape and use of resources. According to Early Holocene palynological data, the landscape was characterised by the progressive expansion of forests, mainly dominated by conifers (pine and juniper) and deciduous trees (oak and hazel). The Holocene Climatic Optimum led to the culmination of forest expansion, with the dominance of dense oak forests, the landscape that the first farming societies found on arrival in this area. During the Middle to Late Holocene transition ( c. 4000 cal BP), the expansion of evergreen sclerophyllous trees and the regression of broadleaf deciduous trees are recorded, in response to both climatic and anthropic causes. Deciduous Quercus and Buxus sempervirens were the most important taxa in all periods and areas, as shown in charcoal data from 26 archaeological levels. However, some other taxa had certain importance in some periods and sites. The variability observed between sites is discussed in terms of the availability of resources and the transformation of landscape evidenced in pollen records. This could explain the appearance of evergreen Quercus and other Mediterranean taxa in the Middle-Late Holocene anthracological record. The characteristics of the sites and socio-historical processes have also been considered in order to understand the use of firewood. In that sense, social necessities would have been the determining factor in planning timber and firewood procurement strategies rather than adapting to the environmental availability. [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]