of Nardus stricta, rich in flowers and sandy mountain soils of the mid-Atlantic or
sub-Atlantic) and ecotonic bands of mountain with clusters of Cytisus
oromediterraneus or Juniperus communis, among others, that colonize the meadows. In many cases, these areas are directly related to the open spaces and ecotonic
areas that contain a great diversity of habitats.
At present, a topic of discussion is whether management must be based on a
certain level of active human disturbance, or if open spaces can be maintained from
a naturalist point of view. Fires and domestic cattle are indispensable elements for
the first option, and there are wild plant-eating animals for the second. A second
idea expressed by Willis and Bhagwat (2010: 765) is that “understanding the
relationship between past herbivore densities and their role as ‘ecosystem engineers’ is an important future research challenge for long-term ecology.” In both
cases, the arboreal reforestation that could exist without either of these interventions
is discarded. Just as we are told that not all meadows have an exclusively human
origin, there are also natural origins, which quickly become the excuse to label the
landscape as deteriorated and of little priority for conservation efforts, when it could
mean exactly the opposite and have important endemic species of high conservation
priority (Willis and Bhagwat 2010).
The altitudinal boundary of the forest is used to study climate change (Grau et al.
2013) and human impact (Catalan et al. 2013). As we have seen, however, the
limits of the ‘natural forested areas’ have been substantially altered by the uses
during recent centuries. That is why managing the forest for multiple uses, agricultural and livestock management and even improving animal habitat require
knowledge of how the forest boundaries have varied to apply conservation policies.
A study by Cunill et al. (2013) carried out in the Vall de Cardós using
pedoanthracology, palynology, and sedimentary charcoals deduced the transformation of the Pyrenean landscape, specifically the forest boundaries, during the
Holocene (Fig. 5.4). Analysis of the data showed that human management has
affected the forest boundaries. Fire, along with pastures and agriculture, has had a
decisive role for thousands of years. Therefore, the current configuration of alpine
and sub-alpine belts has been equally or more influenced by human action than by
climate factors.
We could ask ourselves, why we value stability when studying vegetation
succession but assign less value to systemic stability that results from human
activity. Once again, the discussion must occur between two conflicting points of
view: one side thinks that a certain dose of human disturbance contributes to the
diversity of habitats and, therefore, to biodiversity; the others argue that the absence
of human perturbations and the trend toward landscape homogenization that occurs
with a high degree of maturity (e.g., in a mature forest) is the best way to encourage
the natural system. The key question is, where is the limit? Does the management of
protected natural spaces necessarily favor biodiversity by way of heterogeneity
of habitats or will prolonged homogeneity lead to sufficient maturity and richness of
species and biodiversity over time?
120
A. Pèlachs et al.
sub-Atlantic) and ecotonic bands of mountain with clusters of Cytisus
oromediterraneus or Juniperus communis, among others, that colonize the meadows. In many cases, these areas are directly related to the open spaces and ecotonic
areas that contain a great diversity of habitats.
At present, a topic of discussion is whether management must be based on a
certain level of active human disturbance, or if open spaces can be maintained from
a naturalist point of view. Fires and domestic cattle are indispensable elements for
the first option, and there are wild plant-eating animals for the second. A second
idea expressed by Willis and Bhagwat (2010: 765) is that “understanding the
relationship between past herbivore densities and their role as ‘ecosystem engineers’ is an important future research challenge for long-term ecology.” In both
cases, the arboreal reforestation that could exist without either of these interventions
is discarded. Just as we are told that not all meadows have an exclusively human
origin, there are also natural origins, which quickly become the excuse to label the
landscape as deteriorated and of little priority for conservation efforts, when it could
mean exactly the opposite and have important endemic species of high conservation
priority (Willis and Bhagwat 2010).
The altitudinal boundary of the forest is used to study climate change (Grau et al.
2013) and human impact (Catalan et al. 2013). As we have seen, however, the
limits of the ‘natural forested areas’ have been substantially altered by the uses
during recent centuries. That is why managing the forest for multiple uses, agricultural and livestock management and even improving animal habitat require
knowledge of how the forest boundaries have varied to apply conservation policies.
A study by Cunill et al. (2013) carried out in the Vall de Cardós using
pedoanthracology, palynology, and sedimentary charcoals deduced the transformation of the Pyrenean landscape, specifically the forest boundaries, during the
Holocene (Fig. 5.4). Analysis of the data showed that human management has
affected the forest boundaries. Fire, along with pastures and agriculture, has had a
decisive role for thousands of years. Therefore, the current configuration of alpine
and sub-alpine belts has been equally or more influenced by human action than by
climate factors.
We could ask ourselves, why we value stability when studying vegetation
succession but assign less value to systemic stability that results from human
activity. Once again, the discussion must occur between two conflicting points of
view: one side thinks that a certain dose of human disturbance contributes to the
diversity of habitats and, therefore, to biodiversity; the others argue that the absence
of human perturbations and the trend toward landscape homogenization that occurs
with a high degree of maturity (e.g., in a mature forest) is the best way to encourage
the natural system. The key question is, where is the limit? Does the management of
protected natural spaces necessarily favor biodiversity by way of heterogeneity
of habitats or will prolonged homogeneity lead to sufficient maturity and richness of
species and biodiversity over time?
120
A. Pèlachs et al.