Although rare, temporally and taxonomically highly-resolved palaeoecological studies with high chronological precision are essential to perform detailed comparisons with precisely dated independent ...evidence such as archaeological findings, historical events, or palaeoclimatic data. Using a new highly-resolved and chronologically precise sedimentary record from Lago di Mezzano (central Italy), we reconstruct decadal-scale vegetation, species diversity, and fire dynamics, aiming to better understand the linkages between climate, land use, fire, and plant communities from the Neolithic to the Copper Age (c. 5100–3100 cal. BC). Closed, mixed beech-oak forests, including evergreen Quercus ilex, dominated the landscape around Lago di Mezzano during the Neolithic and were disturbed by repeated opening phases, with important implications for lake biogeochemistry and mixing regimes. This was in conjunction with increasing fire activity to promote agro-pastoral practices, as inferred from increasing charcoal, Cerealia type, Triticum type, Hordeum type, Plantago lanceolata type, and Urtica pollen. Fires, on their turn, augmented species diversity (richness and evenness). The comparison of the Mediterranean record from Lago di Mezzano with available continuous and high-precision submediterranean and cool-temperate palynological sequences suggests comparable land use pulses across Southern and Central European regions, most likely in connection with climate change. The outcomes of this study are not only of palaeoecological and archaeological interest; they may also help to improve projections of ecosystem dynamics under future global change.
Both climate change and anthropogenic disturbance affect vegetation composition, but it is difficult to separate these drivers of vegetation change from one another. A better understanding of past ...vegetation dynamics is necessary to disentangle the influence of different forcing factors and assess future vegetation change. Here we present the first multi-proxy palaeoecological study combining sedimentary ancient DNA (sedaDNA), pollen, spores, stomata, charcoal and plant macrofossils from the Alps. We reconstructed the Holocene vegetation dynamics and fire history at Lago Inferiore del Sangiatto (1980 m asl), a small lake in the subalpine belt of the Ossola region, Italian Lepontine Alps. Afforestation in response to climate warming started at 10,700 cal yr BP with Larix decidua and tree Betula, which formed open forests together with Pinus cembra from 10,500 cal yr BP onwards. Human impact on the regional vegetation started at 5100 cal yr BP, resulting in expansions of Picea abies and Alnus viridis and the collapse of Abies alba. Species response models and ordination analysis show that livestock grazing and fire were major drivers of vegetation change at Lago Inferiore del Sangiatto during the late Holocene. Finally, increasing human impact during the Bronze (ca. 4200–2900 cal yr BP) and Iron Age (ca. 2900–2000 cal yr BP) led to the formation of species-rich larch meadows and alpine pastures that are still dominant today. The palaeoecological data suggest that under projected climate change and land abandonment, the treeline ecotone will likely shift to higher altitudes, leading to important changes in species composition and increasing the risk of biodiversity loss.
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•First record in the European Alps combining sedaDNA, pollen and macrofossils.•Afforestation in response to climate warming started at 10,700 cal yr BP.•First human impact on the vegetation is visible from 5,100 cal yr BP.•Livestock grazing and fire were major drivers of vegetation change.•Humans created species-rich larch meadows and alpine pastures.
Detailed knowledge about the interactions between vegetation, climate and land use during the Mesolithic and Neolithic, at the transition from foraging to farming, is still scarce in the Balkans. ...Here we present a palaeoecological study combining pollen, spores and charcoal found in sedimentary cores from Lake Ohrid, Ploča Mičov Grad, North Macedonia, with a particular focus on the vegetation dynamics during the Late Glacial-Holocene and the Mesolithic-Neolithic transitions. Our record begins at ca. 13,500 cal
bp
(11,550 cal
bc
) when partially open vegetation, consisting mainly of
Pinus
,
Abies
and deciduous
Quercus
tree stands grew on the hilly flanks of the bay of Ploča. From 12,650 cal
bp
(cal 10,700
bc
), herbs dominated the record until the onset of the Holocene (ca. 11,700 cal
bp
; 9750 cal
bc
), when increasing temperatures led to the establishment of pine-deciduous oak forests including
Alnus
,
Fraxinus ornus
,
Tilia
,
Ulmus
and
Abies
. These forests persisted until 7,500 cal
bp
(cal 5550
bc
), when deforestation started due to Neolithic land use. This first phase of Neolithic activities in the Ploča Mičov Grad area precedes the earliest archaeological structures so far recorded by almost 1,000 years. Our data suggest two phases of human land use between 7,500 and 6,300 cal
bp
(5550–4350 cal
bc
), when high values of Cerealia type pollen and other cultural indicators indicate intense arable and pastoral farming activities. Once human activities decreased, forests were able to re-establish quickly (within 100–250 years), although the composition changed with disturbance-adapted
Ostrya
type (mostly
Ostrya carpinifolia
) and
Fagus
becoming more important. We conclude that forests were resilient to early human disturbance, despite intensive land use and logging activities gradually leading to forest composition changes. Many of these composition changes can still be seen today, suggesting the legacy of Neolithic farmers is still present in today’s landscape.
