Little is known about the vegetation and fire history of Sardinia, and especially the long-term history of the thermo-Mediterranean belt that encompasses its entire coastal lowlands. A new sedimentary record from a coastal lake based on pollen, spores, macrofossils and microscopic charcoal analysis is used to reconstruct the vegetation and fire history in north-eastern Sardinia. During the mid-Holocene (c. 8,100-5,300 cal BP), the vegetation around Stagno di Sa Curcurica was characterised by dense Erica scoparia and E. arborea stands, which were favoured by high fire activity. Fire incidence declined and evergreen broadleaved forests of Quercus ilex expanded at the beginning of the late Holocene. We relate the observed vegetation and fire dynamics to climatic change, specifically moister and cooler summers and drier and milder winters after 5,300 cal BP. Agricultural activities occurred since the Neolithic and intensified after c. 7,000 cal BP. Around 2,750 cal BP, a further decline of fire incidence and Erica communities occurred, while Quercus ilex expanded and open-land communities became more abundant. This vegetation shift coincided with the historically documented beginning of Phoenician period, which was followed by Punic and Roman civilizations in Sardinia. The vegetational change at around 2,750 cal BP was possibly advantaged by a further shift to moister and cooler summers and drier and milder winters. Triggers for climate changes at 5,300 and 2,750 cal BP may have been gradual, orbitallyinduced changes in summer and winter insolation, as well as centennial-scale atmospheric reorganizations. Open evergreen broadleaved forests persisted until the twentieth century, when they were partly substituted by widespread artificial pine plantations. Our results imply that highly flammable Erica vegetation, as reconstructed for the mid-Holocene, could re-emerge as a dominant vegetation type due to increasing drought and fire, as anticipated under global change conditions.

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a b s t r a c tVegetation changes in the Maya Lowlands during the Holocene are a result of changing climate conditions, solely anthropogenic activities, or interactions of both factors. As a consequence, it is difficult to assess how tropical ecosystems will cope with projected changes in precipitation and land-use intensification over the next decades. We investigated the role of fire during the Holocene by combining macroscopic charcoal and the molecular fire proxies levoglucosan, mannosan and galactosan. Combining these two different fire proxies allows a more robust understanding of the complex history of fire regimes at different spatial scales during the Holocene. In order to infer changes in past biomass burning, we analysed a lake sediment core from Lake Pet en Itz a, Guatemala, and compared our results with millennial-scale vegetation and climate change available in the area. We detected three periods of high fire activity during the Holocene: 9500e6000 cal yr BP, 3700 cal yr BP and 2700 cal yr BP. We attribute the first maximum mostly to climate conditions and the last maximum to human activities. The rapid change between burned vegetation types at the 3700 cal yr BP fire maximum may result from human activity.

Knowledge about vegetation and fire history of the mountains of Northern Sicily is scanty. We analysed five sites to fill this gap and used terrestrial plant macrofossils to establish robust radiocarbon chronologies. Palynological records from Gorgo Tondo, Gorgo Lungo, Marcato Cixé, Urgo Pietra Giordano and Gorgo Pollicino show that under natural or near natural conditions, deciduous forests (Quercus pubescens, Q. cerris, Fraxinus ornus, Ulmus), that included a substantial portion of evergreen broadleaved species (Q. suber, Q. ilex, Hedera helix), prevailed in the upper meso-mediterranean belt. Mesophilous deciduous and evergreen broadleaved trees (Fagus sylvatica, Ilex aquifolium) dominated in the natural or quasi-natural forests of the oro-mediterranean belt. Forests were repeatedly opened for agricultural purposes. Fire activity was closely associated with farming, providing evidence that burning was a primary land use tool since Neolithic times. Land use and fire activity intensified during the Early Neolithic at 5000 BC, at the onset of the Bronze Age at 2500 BC and at the onset of the Iron Age at 800 BC. Our data and previous studies suggest that the large majority of open land communities in Sicily, from the coastal lowlands to the mountain areas below the thornycushion Astragalus belt (ca. 1,800 m a.s.l.), would rapidly develop into forests if land use ceased. Mesophilous Fagus-Ilex forests developed under warm mid Holocene conditions and were resilient to the combined impacts of humans and climate. The past ecology suggests a resilience of these summer-drought adapted communities to climate warming of about 2°C. Hence, they may be particularly suited to provide heat and drought-adapted Fagus sylvatica ecotypes for maintaining drought-sensitive Central European beech forests under global warming conditions.

Knowledge about the vegetation history of Sardinia, the second largest island of the Mediterranean, is scanty. Here, we present a new sedimentary record covering the past ~ 8,000 years from Lago di Baratz, north-west Sardinia. Vegetation and fire history are reconstructed by pollen, spores, macrofossils and charcoal analyses and environmental dynamics by high-resolution element geochemistry together with pigment analyses. During the period 8,100–7,500 cal bp, when seasonality was high and fire and erosion were frequent, Erica arborea and E. scoparia woodlands dominated the coastal landscape. Subsequently, between 7,500 and 5,500 cal bp, seasonality gradually declined and thermo-mediterranean woodlands with Pistacia and Quercus ilex partially replaced Erica communities under diminished incidence of fire. After 5,500 cal bp, evergreen oak forests expanded markedly, erosion declined and lake levels increased, likely in response to increasing (summer) moisture availability. Increased anthropogenic fire disturbance triggered shrubland expansions (e.g. Tamarix and Pistacia) around 5,000–4,500 cal bp. Subsequently around 4,000–3,500 cal bp evergreen oak-olive forests expanded massively when fire activity declined and lake productivity and anoxia reached Holocene maxima. Land-use activities during the past 4,000 years (since the Bronze Age) gradually disrupted coastal forests, but relict stands persisted under rather stable environmental conditions until ca. 200 cal bp, when agricultural activities intensified and Pinus and Eucalyptus were planted to stabilize the sand dunes. Pervasive prehistoric land-use activities since at least the Bronze Age Nuraghi period included the cultivation of Prunus, Olea europaea and Juglans regia after 3,500–3,300 cal bp, and Quercus suber after 2,500 cal bp. We conclude that restoring less flammable native Q. ilex and O. europaea forest communities would markedly reduce fire risk and erodibility compared to recent forest plantations with flammable non-native trees (e.g. Pinus, Eucalyptus) and xerophytic shrubland (e.g. Cistus, Erica).