extension of forest area in the Pyrenees (approximately 50,000 ha); we find the
southernmost populations in the Montseny massif (Costa et al. 1998). At present,
the stands are highly fragmented and in some cases degraded by human activity
(Alba–Sánchez et al. 2010). Their environmental needs include atmospheric
humidity, dense cover for proper germination, and resistance to cold, placing this
species below the altitude limits of Pinus uncinata, in other words at the subalpine
and montane level. The species can also share the ecological range of Fagus
sylvatica, with which it can form mixed stands of forest (Costa et al. 1998).
The available information about the paleogeographic history of Abies alba and
its current distribution generates a long list of questions about its environmental
history (genetic changes, a shift in distribution areas, etc.) and origins (colonization,
refuge populations, etc.) in the Iberian peninsula. These questions must be
answered to understand its current distribution, predict future developments within
the current framework of global change, and support better management of the
species.
Various paleogeographic studies at the European level, mainly in the Alps and
Apennines, have shown the decrease in the distribution area of firs, compared to the
mid-Holocene (ca. 5000–6000 years ago). At that time, the species would have
achieved a dominant presence in the montane zones and low-altitude areas
(Schneider and Tobolski 1985; Tinner et al. 1999; Wick and Möhl 2006). In the
Pyrenees, environmental geohistory studies have confirmed this trend (Jalut 1988;
Pèlachs et al. 2009b; Galop et al. 2013; Cunill et al. 2015). A study by Cunill et al.
(2015) in fir populations at 300 m altitude on the north slope of the Pyrenees
showed that, far from being anomalies or the fruits of repopulation efforts, these
arboreal masses are witness to the greater importance of firs in the past in low
pre-Pyrenees zones and a presence in the area for at least 5000 years.
It has not always been possible to apply the concepts of resilience, baseline, and
RNV to managing these forests because we still lack knowledge of their paleoecological history and distribution. During the late glacial periods, Abies alba
withdrew to refuge zones (still little-known to this day) and then at the beginning of
the Holocene migrated progressively from east to west along the Pyrenees range. It
appears earlier in the Mediterranean Pyrenees (in Estanilles about 8500 years cal
BP, in the Burg Lake about 8000 years cal BP), and later in the Bassa Nera of the
Atlantic-influenced Aran Valley (at about 6500 years cal BP) (Jalut et al. 1998;
Esteban et al. 2003; Pèlachs et al. 2009b). In coming years, recently initiated pollen
and genetic studies should begin to provide more information on this topic
(Sancho–Knapik et al. 2014; Matías et al. 2016).
Palynological studies of five sedimentary records (Fig. 5.1) confirm the change
over time in the presence of Abies alba and provide new data about the chronology
of its dynamics (Pèlachs et al. 2009b; Bal et al. 2011; Pérez–Obiol et al. 2012;
Cunill et al. 2013). In addition, other techniques of high spatial precision such as
soil charcoal analysis or sedimentary macroremains analysis have confirmed this
chronology and provided more information about the altitudinal and local distribution. Our group has found Abies alba on the shady and sunny sides of both slopes
5 The Role of Environmental Geohistory …
115
southernmost populations in the Montseny massif (Costa et al. 1998). At present,
the stands are highly fragmented and in some cases degraded by human activity
(Alba–Sánchez et al. 2010). Their environmental needs include atmospheric
humidity, dense cover for proper germination, and resistance to cold, placing this
species below the altitude limits of Pinus uncinata, in other words at the subalpine
and montane level. The species can also share the ecological range of Fagus
sylvatica, with which it can form mixed stands of forest (Costa et al. 1998).
The available information about the paleogeographic history of Abies alba and
its current distribution generates a long list of questions about its environmental
history (genetic changes, a shift in distribution areas, etc.) and origins (colonization,
refuge populations, etc.) in the Iberian peninsula. These questions must be
answered to understand its current distribution, predict future developments within
the current framework of global change, and support better management of the
species.
Various paleogeographic studies at the European level, mainly in the Alps and
Apennines, have shown the decrease in the distribution area of firs, compared to the
mid-Holocene (ca. 5000–6000 years ago). At that time, the species would have
achieved a dominant presence in the montane zones and low-altitude areas
(Schneider and Tobolski 1985; Tinner et al. 1999; Wick and Möhl 2006). In the
Pyrenees, environmental geohistory studies have confirmed this trend (Jalut 1988;
Pèlachs et al. 2009b; Galop et al. 2013; Cunill et al. 2015). A study by Cunill et al.
(2015) in fir populations at 300 m altitude on the north slope of the Pyrenees
showed that, far from being anomalies or the fruits of repopulation efforts, these
arboreal masses are witness to the greater importance of firs in the past in low
pre-Pyrenees zones and a presence in the area for at least 5000 years.
It has not always been possible to apply the concepts of resilience, baseline, and
RNV to managing these forests because we still lack knowledge of their paleoecological history and distribution. During the late glacial periods, Abies alba
withdrew to refuge zones (still little-known to this day) and then at the beginning of
the Holocene migrated progressively from east to west along the Pyrenees range. It
appears earlier in the Mediterranean Pyrenees (in Estanilles about 8500 years cal
BP, in the Burg Lake about 8000 years cal BP), and later in the Bassa Nera of the
Atlantic-influenced Aran Valley (at about 6500 years cal BP) (Jalut et al. 1998;
Esteban et al. 2003; Pèlachs et al. 2009b). In coming years, recently initiated pollen
and genetic studies should begin to provide more information on this topic
(Sancho–Knapik et al. 2014; Matías et al. 2016).
Palynological studies of five sedimentary records (Fig. 5.1) confirm the change
over time in the presence of Abies alba and provide new data about the chronology
of its dynamics (Pèlachs et al. 2009b; Bal et al. 2011; Pérez–Obiol et al. 2012;
Cunill et al. 2013). In addition, other techniques of high spatial precision such as
soil charcoal analysis or sedimentary macroremains analysis have confirmed this
chronology and provided more information about the altitudinal and local distribution. Our group has found Abies alba on the shady and sunny sides of both slopes
5 The Role of Environmental Geohistory …
115