36
species or threatened genetic resources but on landscapes of tourist attraction or
species of social interest. As an example, conservation of Nothofagus alpina, appreciated for its wood quality, was the main aim for the creation of Lanín National Park
in 1937. This park covers almost the whole natural range of the species in Argentina
(Sabatier et al. 2011). In addition, other six National Parks were subsequently created with the aim of protecting the Subantarctic forests: “Los Arrayanes,” “Lago
Puelo,” “Los Alerces,” “Perito Moreno,” “Los Glaciares,” and “Tierra del Fuego.”
All these National Parks cover the more humid area of the Andean Patagonian forests, where lush vegetation grows, leaving aside the ecotone zones and the steppe.
Paradoxically, these left out areas harbor genetic hotspots of some of the most
emblematic species of Patagonia such as A. chilensis (Pastorino and Gallo 2002;
Arana et al. 2010), A. araucana (Gallo et al. 2004; Marchelli et al. 2010), and
Fitzroya cupressoides (Premoli et al. 2000a).
However, forest conservation should not be restricted to preserving natural areas
but to also promoting its sustainable management. The traditional exploitation
implemented during the first half of the twentieth century consisted in a high grading sivicultural management, i.e., selection and cutting of all mature good-quality
trees from a forestry point of view. This method changed to modern conceptions
where promoting recruitment of new individuals through natural regeneration is of
primary concern. Then, for example, the shelterwood system consists of successive
regeneration cuttings (preparatory cuts in immature stands and seed cuts in mature
stands) which retain a forest cover of around 30–40%, until completing the regeneration phase (ca. 20 years) (Chauchard et al. 2012). This management system is
being used for the Nothofagus mixed forest within Lanín National Park (Sola et al.
2020). More recently, other methods also stimulating natural regeneration by opening the canopy are being implemented. Variable retention, for example, has been
designed to conserve the original biodiversity and to maintain some heterogeneity
in old-growth forests and is used for management of N. pumilio forests in Tierra del
Fuego island (Martínez Pastur et al. 2011). Nowadays, forestry in the AndeanPatagonian forests focuses on the provinces of Tierra del Fuego and Chubut, where
the main species under use is N. pumilio. At a lower scale, silvicultural management
of A. chilensis in being done, as well as of N. alpina and N. obliqua in Lanín National
Park as mentioned before.
In spite of the protection of large areas of the Subantarctic forests under national
or provincial parks, two main menaces attempt against its preservation. Firstly, forest fires, mainly of anthropic origin that usually light in the outskirts of the main
cities. Between 1993 and 1999, forest fires affected about 57,900 ha of native forests in the Provinces of Río Negro and Chubut. In addition, 44,257 ha of native
forests burnt in 2015 in the Provinces of Neuquén, Río Negro, and Chubut, from
which 27,101 ha belonged to a single forest fire at Las Horquetas – Cholila (MohrBell 2015). Climate change predictions foreseen an increase in the frequency of
fires (Veblen et al. 2011) causing concern for the future of these forests.
The other menace against the conservation of the Andean-Patagonian forests is
the progress of urbanizations. In a region with a population growth rate doubling
that of the rest of the country (INDEC 2012), there is genuine need to have land for
P. Marchelli et al.
species or threatened genetic resources but on landscapes of tourist attraction or
species of social interest. As an example, conservation of Nothofagus alpina, appreciated for its wood quality, was the main aim for the creation of Lanín National Park
in 1937. This park covers almost the whole natural range of the species in Argentina
(Sabatier et al. 2011). In addition, other six National Parks were subsequently created with the aim of protecting the Subantarctic forests: “Los Arrayanes,” “Lago
Puelo,” “Los Alerces,” “Perito Moreno,” “Los Glaciares,” and “Tierra del Fuego.”
All these National Parks cover the more humid area of the Andean Patagonian forests, where lush vegetation grows, leaving aside the ecotone zones and the steppe.
Paradoxically, these left out areas harbor genetic hotspots of some of the most
emblematic species of Patagonia such as A. chilensis (Pastorino and Gallo 2002;
Arana et al. 2010), A. araucana (Gallo et al. 2004; Marchelli et al. 2010), and
Fitzroya cupressoides (Premoli et al. 2000a).
However, forest conservation should not be restricted to preserving natural areas
but to also promoting its sustainable management. The traditional exploitation
implemented during the first half of the twentieth century consisted in a high grading sivicultural management, i.e., selection and cutting of all mature good-quality
trees from a forestry point of view. This method changed to modern conceptions
where promoting recruitment of new individuals through natural regeneration is of
primary concern. Then, for example, the shelterwood system consists of successive
regeneration cuttings (preparatory cuts in immature stands and seed cuts in mature
stands) which retain a forest cover of around 30–40%, until completing the regeneration phase (ca. 20 years) (Chauchard et al. 2012). This management system is
being used for the Nothofagus mixed forest within Lanín National Park (Sola et al.
2020). More recently, other methods also stimulating natural regeneration by opening the canopy are being implemented. Variable retention, for example, has been
designed to conserve the original biodiversity and to maintain some heterogeneity
in old-growth forests and is used for management of N. pumilio forests in Tierra del
Fuego island (Martínez Pastur et al. 2011). Nowadays, forestry in the AndeanPatagonian forests focuses on the provinces of Tierra del Fuego and Chubut, where
the main species under use is N. pumilio. At a lower scale, silvicultural management
of A. chilensis in being done, as well as of N. alpina and N. obliqua in Lanín National
Park as mentioned before.
In spite of the protection of large areas of the Subantarctic forests under national
or provincial parks, two main menaces attempt against its preservation. Firstly, forest fires, mainly of anthropic origin that usually light in the outskirts of the main
cities. Between 1993 and 1999, forest fires affected about 57,900 ha of native forests in the Provinces of Río Negro and Chubut. In addition, 44,257 ha of native
forests burnt in 2015 in the Provinces of Neuquén, Río Negro, and Chubut, from
which 27,101 ha belonged to a single forest fire at Las Horquetas – Cholila (MohrBell 2015). Climate change predictions foreseen an increase in the frequency of
fires (Veblen et al. 2011) causing concern for the future of these forests.
The other menace against the conservation of the Andean-Patagonian forests is
the progress of urbanizations. In a region with a population growth rate doubling
that of the rest of the country (INDEC 2012), there is genuine need to have land for
P. Marchelli et al.