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For several decades, conventional pollen analyses have been supplemented with information provided by Non-Pollen Palynomorphs (NPP). Generally, the taxa included in this group are microalgae, fungi, insects and arachnid's chitinous remains, as well as plant debris and other organic palynomorphs of undetermined origin, that are valuable tools with which to characterise the original strata as well as the local environmental features that influence deposit formation processes. In this work, we present the results of the NPP analysis of the archaeological and palaeontological deposits of Sima del Elefante, Gran Dolina and Galería, all of which are located in the Trinchera area (Sierra de Atapuerca, Burgos), spanning a period from 200 ka to almost 1.5 million years ago. The NPP analysis of the three deposits has provided information about the presence of decayed organic matter accumulations, erosion processes and moisture conditions. Knowledge of palynomorphs contributes to the understanding of the biological, physical and chemical dynamics that resulted in different sedimentary sequences. In almost all cases, there is a clear connection between the major stratigraphic trends established for the three deposits and the NPP assemblages identified. However, the eminently local character of the dispersion of most of the palynomorphs identified has prevented the interrelation between the three sequences analysed. [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]