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179
IX/2/2018
INTERDISCIPLINARIA ARCHAEOLOGICA
NATURAL SCIENCES IN ARCHAEOLOGY
homepage: http://www.iansa.eu
Holocene Vegetation Dynamics and First Land-Cover Estimates in the
Auvergne Mountains (Massif Central, France): Key Tools to Landscape
Management
Yannick Miras
a,b*
, Michela Mariani
c
, Paul M. Ledger
b
, Alfredo Mayoral
b
,
Léo Chassiot
d,e
, Marlène Lavrieux
d,f
a
CNRS, UMR 7194, Histoire Naturelle de l’Homme Préhistorique, Muséum National d’Histoire Naturelle, Institut de Paléontologie Humaine,
1 rue René Panhard, 75013 Paris, France
b
CNRS, Université Clermont Auvergne, GEOLAB, F-63000 Clermont-Ferrand, France
c
School of Geography, University of Melbourne, 221 Bouverie Street, Parkville VIC 3010, Australia
d
CNRS, UMR 7327, Institut des Sciences de la Terre d’Orléans (ISTO), Université d’Orléans/BRGM, 1A rue de la Férollerie, 45071 Orléans Cedex 2, France
e
INRS – Eau Terre Environnement, 490 rue de la Couronne, Québec, QC, G1K 9A9, Canada
f
University of Basel, Department of Environmental Sciences, Bernoullistrasse 30, 4056 Basel, Switzerland
1. Introduction
The nomination of the “Chaîne des Puys” to the UNESCO
World Heritage list makes the development of sustainable
management strategies of current landscapes of the
Auvergne mountains a pressing concern (Ballut
et al
., 2012;
Miras
et al
., 2015). The development of such strategies is
a priority as human-induced ecological disturbances are
already being observed, particularly a loss in biodiversity
in diferent plant communities (Carrère
et al
., 2014). The
causes of this are numerous and include the destruction
of natural habitats, a widespread enhanced erosion and
organic pollution. Although the Chaîne des Puys is located
in a Natural Park (“Parc Naturel Régional des Volcans
d’Auvergne”), this volcanic mid-mountain area (up to
1465 m asl) is characterized by a relatively dense human
occupation. Thus, anthropogenic pressure is current and
mainly induced through agropastoralism and tourism. The
process of environmental-decision making must therefore
ensure environmental quality, biodiversity conservation and
restoration of ecosystem services without preventing socio-
economic development, which is vital for this rural territory.
Volume IX ● Issue 2/2018 ● Pages 179
–190
*Corresponding author. E-mail: yannick.miras@mnhn.fr
ARTICLE INFO
Article history:
Received: 11
th
May 2018
Accepted: 10
th
November 2018
DOI: http://dx.doi.org/ 10.24916/iansa.2018.2.5
Key words:
vegetation history
cultural landscape
human impact
mountain
Auvergne
Holocene
palaeoecology
pollen
REVEALS
ABSTRACT
A multi-proxy palaeoecological investigation has been undertaken at high spatio-temporal resolution
in the Lower Auvergne Mountains (France). It allows us to investigate the Holocene trajectories
of landscape evolution arising from the interplay between human impact and adaptability, climate
oscillations and environmental evolution. The mechanistic models for the regional vegetation
reconstruction applied here provide the frst quantifcation of land cover changes in this region. The
results obtained allow an improved understanding of past vegetation dynamics and a discussion of:
(1) the natural variability of the vegetation to climate oscillations; (2) the development of the cultural
landscape and the land uses involved; (3) the timing and the extent of the landscape openness; and (4)
the richness in vegetation units within the landscape mosaic measured by the foristic diversity. These
long-term changes highlight the sensitivity of these mountainous landscapes: having formed socio-
ecosystems that have been shaped over millennia. It is therefore crucial to consider this ecological and
cultural heritage when directing future sustainable management plans.
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IANSA 2018 ● IX/2 ● 179–190
Yannick Miras, Michela Mariani, Paul M. Ledger, Alfredo Mayoral, Léo Chassiot, Marlène Lavrieux: Holocene Vegetation Dynamics and First Land-Cover Estimates
in the Auvergne Mountains (Massif Central, France): Key Tools to Landscape Management
180
Previous research has underlined that several fresh
insights for the governance, conservation and promotion
of landscapes can be gained from palaeoenvironmental
research (
e.g.
Ekblom, Gillson, 2017; Mercuri, 2014;
Whitlock
et al
., 2017). In the frst place, palaeoenvironmental
research provides a long-term perspective on the complex
interplay between human impact and adaptability, climate
oscillations and environmental evolution. Secondly, it
allows the reconstruction of the long-term development of
landscapes which are defned nowadays as coupled human-
environment systems – named socio-ecosystems – with
diverse and complex linkages over time (Turner
et al
.,
2003).
Finally, it allows a better characterization through time of
the ecological processes before, during and after an impact
(both natural or human-induced). Moreover, recent advances
in palynology play an important role in this issue as follows:
(1) the multi-proxy study of numerous high-quality pollen
stratigraphical sequences at high spatio-temporal scales (
e.g.
in mountains areas, Ejarque
et al
., 2010; Joufroy-Bapicot
et al
., 2013); (2) the use of mechanistic models for regional
vegetation quantifcation (
e.g.
Gaillard
et al
., 2010; Mariani
et al
., 2017; Mazier
et al
., 2012); and (3) the use of pollen-
assemblage richness indexes which trace the evolution of the
foristic diversity (Birks
et al.
, 2016) and which particularly
assess the infuence of woodland clearance on biodiversity,
in the case of a combined study with land-cover estimates.
The overall objective of this paper is to investigate
the Holocene vegetation history in the Lower Auvergne
Mountains and the long-term shaping of this cultural
landscape as inferred by the high-resolution study of three
lacustrine and peat sequences. In addition, the frst quantitative
reconstructions of land cover have been performed in order
to examine large-scale changes in land cover. REVEALS
converts pollen data collected from large sites or multiple
small sites into plant cover estimates at a macro-regional
level defned at a spatial scale of c. 100×100 km (Sugita,
2007; Trondman
et al
., 2016). Consequently, the frst results
obtained are only discussed with regard to the major trends
of plant-landscape trajectories at a macro-regional scale.
Finally, the potential of the obtained palaeoenvironmental