5.2.4 From the Late Roman to the Medieval Age Was Born
the Open Landscape: Threshold Forestry Without
Turning Back?
If we analyze the intensity of human disturbance in our mountains, agriculture
would be among the most important. As Willis and Bhagwat (2010) point out,
based on examples from around the world, “Many of the landscapes in so-called
biodiversity hotspots have a long history of human habitation and have been under
some form of cultivation in the past” (Willis et al. 2004). The socioeconomic
changes of the second half of the 20th Century led to the abandonment of many
traditional practices related to the primary sector, and the Pyrenees are no exception
(García–Ruíz et al. 1996). The loss of biodiversity associated with farming and
livestock mosaics is a subject of debate in the management of Natural Spaces, to the
extent that in recent years some of them, such as the Alt Pirineu Natural Park, have
put in place policies of recovering fields and planting cereal crops. According to
Willis and Bhagwat (2009: 807), “It has long been assumed that in a fragmented
landscape, the fragment size and its isolation are important factors in determining
species persistence; the smaller and more isolated the fragment, the lower its
occupancy.” One idea that contradicts the forest recolonization that provoked the
abandonment of the traditional farming and livestock system in the valleys and
mid-slopes. Bradshaw et al. (2015) summed it up this way: “Long forest continuity
may be of importance for the local survival of higher plants, but for the insects,
fungi, lichens, and bryophytes that are so valued in contemporary European temperate and boreal forests, habitat diversity maintained by dynamic processes would
appear to be of greater significance” (Bradshaw et al. 2015: 194). This issue is also
under discussion. Should managers strengthen the farming and livestock mosaic?
Should agriculture be incentivized? Managers ask for specific answers, but policy
management must be more general (Dietl and Flessa 2011). The following is an
example of a threshold from more than a thousand years ago.
To understand the agricultural system, we analyzed the curves of cereals and
grasses on the pollen diagram for Burg Lake, observing that the starting point of the
modern farming and livestock system began about 4250 years cal BP (Fig. 5.5).
The trend has clearly been on the increase, especially over the last two millennia. In
other words, in the past 2000 years, there has never been such a small farming and
livestock system in that study area. During those two millennia, the landscape has
almost always been more open than it is now and forest recovery has clearly been in
deficit compared to the recovery of pastures and open spaces.
A paradigmatic case occurred in Estanilles (Fig. 5.2), where deforestation was at
its maximum 500 years ago, with AP% below one-third, coinciding with a maximum
curve of cereal pollen. The peculiarity of this case is that this process occurred at an
altitude of 2247 m.a.s.l., which is usually associated only with pastures. Nonetheless,
the data indicate an open farming and livestock landscape without trees.
Is the speed and intensity of these changes comparable throughout history?
The current landscape often inhibits our ability to see beyond the human scale
122
A. Pèlachs et al.
the Open Landscape: Threshold Forestry Without
Turning Back?
If we analyze the intensity of human disturbance in our mountains, agriculture
would be among the most important. As Willis and Bhagwat (2010) point out,
based on examples from around the world, “Many of the landscapes in so-called
biodiversity hotspots have a long history of human habitation and have been under
some form of cultivation in the past” (Willis et al. 2004). The socioeconomic
changes of the second half of the 20th Century led to the abandonment of many
traditional practices related to the primary sector, and the Pyrenees are no exception
(García–Ruíz et al. 1996). The loss of biodiversity associated with farming and
livestock mosaics is a subject of debate in the management of Natural Spaces, to the
extent that in recent years some of them, such as the Alt Pirineu Natural Park, have
put in place policies of recovering fields and planting cereal crops. According to
Willis and Bhagwat (2009: 807), “It has long been assumed that in a fragmented
landscape, the fragment size and its isolation are important factors in determining
species persistence; the smaller and more isolated the fragment, the lower its
occupancy.” One idea that contradicts the forest recolonization that provoked the
abandonment of the traditional farming and livestock system in the valleys and
mid-slopes. Bradshaw et al. (2015) summed it up this way: “Long forest continuity
may be of importance for the local survival of higher plants, but for the insects,
fungi, lichens, and bryophytes that are so valued in contemporary European temperate and boreal forests, habitat diversity maintained by dynamic processes would
appear to be of greater significance” (Bradshaw et al. 2015: 194). This issue is also
under discussion. Should managers strengthen the farming and livestock mosaic?
Should agriculture be incentivized? Managers ask for specific answers, but policy
management must be more general (Dietl and Flessa 2011). The following is an
example of a threshold from more than a thousand years ago.
To understand the agricultural system, we analyzed the curves of cereals and
grasses on the pollen diagram for Burg Lake, observing that the starting point of the
modern farming and livestock system began about 4250 years cal BP (Fig. 5.5).
The trend has clearly been on the increase, especially over the last two millennia. In
other words, in the past 2000 years, there has never been such a small farming and
livestock system in that study area. During those two millennia, the landscape has
almost always been more open than it is now and forest recovery has clearly been in
deficit compared to the recovery of pastures and open spaces.
A paradigmatic case occurred in Estanilles (Fig. 5.2), where deforestation was at
its maximum 500 years ago, with AP% below one-third, coinciding with a maximum
curve of cereal pollen. The peculiarity of this case is that this process occurred at an
altitude of 2247 m.a.s.l., which is usually associated only with pastures. Nonetheless,
the data indicate an open farming and livestock landscape without trees.
Is the speed and intensity of these changes comparable throughout history?
The current landscape often inhibits our ability to see beyond the human scale
122
A. Pèlachs et al.