Abies pinsapo var. pinsapo

Pinaceae

One of two varieties of the Spanish fir restricted to three areas of southern Spain where in the last 45 years large areas of forest have been lost mainly as a result of fire.

Description

Habit

Tree to 30m tall, d.b.h. 1–1.5m; trunk straight but sometimes forked or twisted; crown narrowly conical in young trees and irregular in mature trees. Bark smooth and dark grey in young trees, rough and scaly in old trees. Branches, lower curved downwards, uppermost ascending, branchlets very rigid, reddish brown or greenish brown, vegetative buds ovoid–globose, 5–-6 x 4–4.5mm, greenish to purple-brown

Foliage

Leaves spirally arranged all around shoot radially and perpendicularly from the shoot, those below bent backwards; 1–1.8cm, leathery, stiff, bluntly rounded (fully exposed); dull grey-green or blue-grey with two broad stomatal bands of grey-green or dull bluish white on each surface.

Cones

Female cones 9–14cm x 3–4cm, abruptly narrowed to apex, greenish purple when immature, ripening dark or light brown. Male cones crowded along underside of shoot, dark brown, opening cherry–red.

Notes

This is one of two varieties, the other being A. pinsapo var marocana (treated on a seperate page), which is native to north Morocco. The differencies between these two varieties is slight; in var. marocana the leaves are arranged around the shoot pectinately and not radially and perpendicularly from the shoot as in var. pinsapo. The female cones in the var. marocana are much larger, 10–18 x 3.5–5cm.

Distribution

Abies pinsapo var. pinsapo occurs in three locations: Sierra de Grazalema (Cádiz), Sierra de las Nieves and Sierra Bermeja (Málaga). The largest forests occur in Sierra de Grazalema and Sierra de las Nieves. In total the population has an extent of occurrence of 940km² with an area of occupancy 28.7km²

In the Sierra de Grazalema the main distribution is along the Sierra del Pinar where it is restricted to an area of occupancy of 4km²; the three small localities in this area contain trees which have not yet reached reproductive age. In the Sierra de las Nieves location most trees are concentrated in the municipalities of Yunquera, Ronda and Tolox, where they occur in an area of 24km². The smallest and most isolated subpopulation is at Los Reales, within the Sierra Bermeja, where it is restricted to a small area of 0.7km². There are currently no accurate figures for the total number of mature individuals over the full extent of its range.

Habitat and Ecology

It grows mainly on northerly exposures of the Sub-Betic mountains. The trees in Sierra de Grazalema and Sierra de las Nieves occur on dolomitic soils and have an altitudinal range of 900 to 1,600 m. Above 1,100m they form dense, pure forests, but below this altitude they form mixed communities in dense forest with Quercus rotundifolia and Q. faginea and with a shrub layer mainly of Daphne laureola ssp. latifolia, Hedera helix, Helleborus foetidus, Ruscus aculeatus and the herbs Iris foetidissima and Rubia peregrina. In the more open forest areas the fir is associated with Crataegus monogyna ssp. brevispina, Prunus spinosa, Ptilotrichum spinosum, Bupleurum spinosum, B. gibraltaricum and Cistus albidus. The forest in Sierra Bermeja is on serpentine soils and here the tree layer occurs with Quercus suber and with other conifers such as Pinus pinaster and P. halepensis (this association is also occasionally found on calcareous soils). The shrub layer on serpentine soils is composed of Erica terminalis, Genista lanuginosa, G. triacanthos, Cistus populifolius ssp. major, Bunium alpinum ssp. macuca and Cerastium gibraltaricum. Abies pinsapo has a reproductive cycle of one year; the differentiation of reproductive buds occurs in July and pollen shed and female cone receptivity occurs in April to May. Wind-borne pollen dispersal has a low capacity. Fertilization occurs two months after pollination and female cones achieve their full development by June. Seeds begin to shed in October and they enter dormancy until February when germination occurs; seeds that fail to germinate in this year die, hence there is no persistent seed bank formed.

Human Uses

The timber has historically been locally used for house construction. The forests in the Sierra del Pinar were managed for timber production but there is no present-day use of the timber.

Conservation Status

Global Status and Rationale

Endangered B1ab(iii)+2ab(iii)

Fire is the main threat to this taxon and during the last 45 years, 566 hectares of forests has been lost. Abies pinsapo is not fire-adapted; it does not have the ability to regenerate from sprouting and there is a lack of seed longevity, hence there is no soil seed bank available for potential post fire regeneration. Other threats include pests and diseases which have increased in their occurrence over the last 15 years, especially in drought years and in forests resulting from reforestation. The main pathogens are the fungi Armillaria mellea and Heterobasidium annosum, and the insect species Dioryctria aulloi and Cryphalus numidicus. The latter is the most detrimental insect as it attacks the trunk and branches causing death. The isolation of populations due to fragmentation and a low genetic flow is currently an important risk that could give rise to a low genetic diversity within populations which would make them more susceptible to diseases. Threats from livestock are no longer a problem. During the last decade (1990s) a regional warming trend and a the decrease in precipitation has been observed. These changes in climate together with changes in landuse appear to be the causes of mortality of trees at elevations below 1100m (Linares, 2009). The extent of occurrence has been calculated as being 940km² and the area of occupancy has been calculated as being 28.7km²; when a standard 4km² grid is used, the area of occupancy is between 10km² and 500km². The number of locations is limited to three.

Conservation Actions

Abies pinsapo var. pinsapo is protected at a regional level under the Spanish law in the “Andalusian Catalogue of Threatened Wild Plants“ (Decree 104/94) which means that it has to have a plan of conservation which is currently being developed. At the European level, the forests have been included in the Habitats Directive (92/43/CEE).

In situ conservation action: i) most of the forests are included in the so-called “Network of Protected Areas in Andalusia”: Sierra de Grazalema Natural Park (1984), Sierra de las Nieves Natural Park (1989) and Los Reales de Sierra Bermeja Nature Area (1989). ii) In the last seven years the “Action Program for A. pinsapo conservation” has been established. Under this program conservation actions are being carried out which include the prevention of forest fires, phytosanitary treatments, fencing small trees to protect them from livestock, and experimental reforestations.

Ex situ conservation actions are being carried out by the “Andalusian Networks of Botanic Gardens” and the “Andalusian Germoplasm Bank”.

Lastly, research studies are being undertaken to better understand the genetic variability of the remaining forests, the level and frequency of gene flow between them and to assess the possible problems derived from climate change.

References and further reading

Arista, M. (1995). The structure and dynamics of an Abies pinsapo forest in Southern Spain. Forest Ecology and Management. 74: 81–89.
Arista, A., Knees, S. & Gardner, M. 2011. Abies pinsapo var. pinsapo. In: IUCN 2012. IUCN Red List of Threatened Species. Version 2012.2. . Downloaded on 07 March 2013.
Arista, M., Herrera, F.J. & Talavera, S. (1997). Biología del Pinsapo. Junta de Andalucía, Consejería del Medio Ambiente, Seville, Spain.
Arista, M., Talavera, S. & Herrera, F. J.(1997). Abies pinsapo: a protected especies in a protected area. Bocconea. 7: 421-436.
Barbero, M., Bonin, G., Loisel, R. & Quézel, P. (1990). Changes and disturbances of forest ecosystems caused by human activities in the western part of the Mediterranean basin. Vegetatio. 87: 151–173.
Barbey, A. (1931). A Travers les Forêts de Pinsapo d’Andalousie: Étude de Dendrologie, de Sylviculture et d’Entomologie Forestière. Librairie Agricole, Paris, France.
Esteban, L. G., De Palacios, P., Guindeo, A. & García Fernández, F. (2007). Comparative anatomy of the wood of Abies pinsapo and its two Moroccan varieties. IAWA Journal. 28: 285–298
Esteban, L. G., De Palacios, P. & Rodriguez-Losada Aguado, L. (2010). Abies pinsapo forests in Spain and Morocco: threats and conservation. Oryx 44(2): 276-284.
Génova, M. (2007). El crecimiento de Abies pinsapo y el clima de Grazalema: aportaciones dendroecológicas. Investigación Agraria: Sistemas y Recursos Forestales. 16: 145–157.
Herrera, J., Arista, M. & Talavera. S. (1999). Abies pinsapo Boiss. In Blanca G. et al. (eds.) Libro Rojo de la Flora silvestre amenazada de Andalucía. Tomo I: especies en peligro de extinción. Consejería de Medio Ambiente, Junta de Andalucía.
Knees, S.G. 2011. Phylogeny, Systematics and Conservation of Abies, especially those around the Mediterranean Basin. Reading. Unpublished PhD Thesis, University of Reading.
Linares, J. C. & Carreira, J. A. (2006). El pinsapo, abeto endémico andaluz. O, ¿qué hace un tipo como tú en un sitio como éste? Ecosistemas. 3: 171–191.
Linares, J. C. (2008). Efectos del cambio global sobre la dinámica poblacional y la ecofisiología de bosques relictos de Abies pinsapo Boiss. PhD Thesis, Universidad Jaén, Jaén, Spain.
Linares, J. C., Camarero, J. J. & Carreira, J. A. (2009). Interacting effects of changes in climate and forest cover on mortality and growth of the southernmost European fir forests. Global Ecology and Biogeography. 18: 485-497.
Terrab, A., Talavera, S., Arista, M., Paun, O., Stuessy, T. F. & Tremetsberger, K. (2007). Genetic diversity at chloroplast microsatellites (cpSSRs) and geographic structure in endangered West Mediterranean firs (Abies spp., Pinaceae). Taxon 56(2): 409-416.
Soto, D. (2006). Núcleos residuales de pinsapo perdidos en Andalucía en el siglo XX. Investigación Agraria: Sistemas y Recursos Forestales, Special issue. 79–86.