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CAJALBANA TABLELAND
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| Location: Comprises two upland regions near the north coast of western Cuba: the
Cajálbana Tableland and the Preluda Mountain region, located at latitude 22°40'N and
longitude 83°16'W, in the province of Pinar del Rio, about 100 km from La Habana. Area: c. 100 km² Altitude: Cajálbana Tableland reaches 464 m above sea-level; Preluda Mountain is over 200 m above sea-level. Vegetation: Pine forests (with Pinus caribaea), thorny xerophytic thickets, some gallery forests. Flora: c. 353 vascular plant species, including c. 40 strictly endemic species and 4 endemic genera. The region includes the highest concentration of endemic taxa per unit area in Cuba. Useful plants: Pines (e.g. Pinus caribaea) used for timber and as sources of resin. Other values: Seed source of timber trees used in reforestation programmes, high landscape value, potential tourism, forestry education. Threats: Fire, soil erosion, clearance for agriculture, timber exploitation, some tourist activities (e.g. camping). Conservation: The region is traditionally managed as "Forestry Patrimony" and part is included in Mil Cumbres Integrated Management Area (166 km²) (IUCN Management Category: VIII). Map 32: CPD Site CB3 Map 33: CPD Site CB3 Vegetation Zones References |
Geography
The region comprises two upland areas: the Cajálbana Tableland and Preluda Mountain (Map 32). The Cajálbana Tableland is 15 km in length and 9 km wide, parallel to the north coast. The whole region is between 300 and 400 m above sea-level, the highest point reaching 464 m. The southern slopes of the tableland are abrupt. Preluda Mountain lies to the south-west of the Cajálbana Tableland, from which it is separated by the Tortuga River. The easternmost limit is the Puercas River. The mountain is 2 km long and 1 km wide.
Both areas contain old serpentine ultramafic igneous rock basement (peridotites), dating from the Late Cretaceous (100-65 million years BP). The Cajálbana Tableland has very deep red, lateritic or ferritic soils which are slightly acidic, contain high concentrations of nickel and oxides of iron and aluminium, and have a low Ca/Mg ratio. Preluda Mountain and the southern slopes of Cajálbana Tableland are rocky, with undifferentiated serpentine soils (magnesic black soils), which also contain high concentrations of nickel.
The annual rainfall is 1300-1500 mm, with a dry season from November to April and a rainy season from May to October. The mean annual temperature is 25°C (slightly lower at the highest points). The warmest month is August, with a mean temperature of 28°C, and the coldest is January (with a mean of 21.5°C).
Vegetation
Pine forests
Pine forests are the most extensive vegetation over deep lateritic soils on the Cajálbana
Tableland (Map 33), covering nearly 70 km². The canopy is closed,
the main emergent species being Pinus caribaea, which can reach 30 m. In moist
areas, pines are mixed with broadleaved trees, such as Calophyllum pinetorum and Clusia
rosea.
The understorey is very dense and rich in shrubs, most belonging to Rubiaceae, Euphorbiaceae, Myrtaceae and Melastomataceae. Palms of the genera Copernicia and Coccothrinax are particularly distinctive. The shrubs are mainly xerophytic (microphyllous) species, including Jacquinia brunnescens, Vaccinium ramonii, Sauvallella immarginata, Neomazaea phialanthoides, Acuneanthus tinifolius and Malpighia horrida. Mesophytic shrubs include Purdiaea cubensis, Tetrazygia coriacea and Tabebuia lepidota. The herbaceous layer is dominated by grasses of the genera Aristida, Andropogon and Arthrostylidium, herbaceous dicots and ferns, such as Ayenia cajalbanensis, Mitracarpus glabrescens and Anemia cajalbanica. The forests contain some lianas, such as Lescaillea equisetiformis, Cynanchum spp., Aristolochia spp., and the spiny fern Odontosoria wrightiana. Epiphytes include many species of Tillandsia spp.
Where clearances have been made in the past, the canopy of the forest is more open and the shrub layer is dominated by Comocladia dentata (a very poisonous member of the Anacardiaceae); grasses, lianas and epiphytes are poorly represented.
At the southern side of the Cajálbana Tableland, a dry type of pine forest occurs on rocky substrates. It includes pines, thorny shrubs and the succulent Agave cajalbanensis.
Thorny xerophytic thicket
Thorny xerophytic thicket contains the highest floristic diversity of all vegetation types
in the region. It occurs on the rocky (magnesic black) soils of the southern slopes of
Cajálbana Tableland and Preluda Mountain (Map 33). The thicket is
a dense bushy formation, about 3 m high. It includes xeromorphic, sometimes thorny, shrubs
and succulents, with some emergent trees and palms. Examples of the emergent species are: Amyris
lineata, Euphorbia cubensis, Pseudocarpidium ilicifolium and Cocccothrinax
yuraguana. The most abundant shrubs are: Phyllanthus trigonocarpus, Erythroxylum
minutifolium and members of the Rubiaceae, Myrtaceae and Euphorbiaceae.
The herb layer is rich in species of Aristida, Andropogon and Arthrostylidium. Other interesting herbaceous plants include Heptanthus ranunculoides, Lachnorhiza piloselloides and the cycad Zamia kickii. Lianas include Mesechites rosea and Jacquemontia spp. Epiphytes are represented principally by species of Tillandsia and Encyclia.
Gallery forests
Gallery (riverine) forests are developed on alluvial deposits along rivers (especially the
Tortuga River) and streams (Map 33). The tree layer has a dense
canopy, with Didymopanax morototoni, Bombacopsis emarginata, Syzygium
jambos and Dendropanax cuneifolius, and the palms Calyptrogyne dulcis
and Copernicia glabrescens, among others.
The shrub layer is dense and comprises mesophytic plants, such as Rondeletia peduncularis and Calyptranthes enneantha. The herb layer includes Pinillosia berteri, Wedelia rugosa, Pinguicula albida and grasses such as Mniochloa strephioides and Arthostylidium capillifolium. Species of Adiantum, Blechnum, Polypodium and Thelypteris are the most common ferns. Lianas include Dioscorea wrightii, Vanilla dilloniana and Clematis dioica. Orchids, such as Encyclia spp. and Epidendrum spp., are among the epiphytes.
Compared to the other formations, gallery forests have relatively low species endemism.
Flora
Borhidi (1991) considers the Cajálbana Mountains (Cajalbanense) to be a separate floristic district within the Pinar del Rio sector of the phytogeographic Sub-Province of Western Cuba (Occidento-Cubanicum) (see CPD Site Cb3 in Regional Overview).
The flora of Cajálbana Tableland and Preluda Mountain contains nearly 330 species of angiosperms, 3 species of gymnosperms and c. 20 species of ferns and fern allies. Of the 181 genera of angiosperms in Cuba, 75 are found in the district. Families with the most number of species are Rubiaceae (40), Compositae (27), Gramineae (24), Euphorbiaceae (18), Myrtaceae (15) and Leguminosae (15). There are 4 strictly endemic genera, namely: Neomazaea, Sauvallella, Phyllacanthus and Lescaillea (all of which are monotypic) and about 40 strictly endemic species, many of which are found on serpentine soils. Indeed, the Cajálbana Tableland and Preluda Mountain Region has the highest concentration of endemic taxa per unit area in the whole of Cuba.
Useful plants
The most important species are pines (especially Pinus caribaea), which are used as sources of timber, resin and other products. The region contains an important gene pool for species used in reforestation programmes in Cuba.
Local people use the leaves of the palm Coccothinax yuraguana (yuraguano) as roofing material for their houses.
Social and environmental values
Only a few people live in the upper part of the Cajálbana Tableland, where there is a Forestry School. The Preluda Mountain is uninhabited.
The region is the source of several rivers. The landscape is one of the most beautiful in western Cuba and has considerable potential for tourism.
Cuba and the Bahama Islands constitute one Endemic Bird Area (EBA) with a total of 24 restricted-range landbirds occurring of which 19 are endemic; 13 of these birds are confined to Cuba and the Isle of Pines only. A further nine species are endemic to Cuba, but occur on the island widely, and thus do not qualify as restricted-range. Habitat requirements vary but many species are reliant on forest (including pine forest) and woodland.
Threats
The most serious threat is fire, which can spread rapidly through the xeromorphic and resiniferous vegetation.
Agriculture is increasing around the perimeter of the area. Timber exploitation and, to some extent, tourism could increase soil erosion and open up areas to invasion by exotic plant species.
Table 48 shows the 18 strict endemic taxa that are considered to be rare or threatened according to the IUCN Red Data Book categories; several more taxa may also qualify for listing.
Conservation
The region is traditionally managed as "Forestry Patrimony". The southern side of Cajálbana Tableland is included in the Mil Cumbres Integrated Management Area (of area 166 km²) (IUCN Management Catagory: VIII).
Fires are controlled by planting broadleaved plants as barriers and by creating firebreaks in the forest.
Map 32. Cajalbana Tableland and Preluda Mountain Region, Cuba (CPD Site CB3, in part)
Map 33. Cajalbana Tableland and Preluda Mountain Region, Cuba (CPD Site CB3, in part), showing vegetation zones
Alain, H. (1950). Notas sobre la vegetación de la loma de Cajálbana, Pinar del Rio. Rev. Soc. Cub. Bot. 7(1): 8-18.
Berazaín, R. (1987). Notas sobre la vegetación y flora de la Sierra de Cajálbana y Sierra Preluda (Pinar del Rio) Rev. Jardín Bot. Nac. 8(3): 39-68.
Borhidi, A. (1987). The main vegetation units of Cuba. Acta Bot. Hung. 33(3-4): 151-185.
Borhidi, A. (1991). Phytogeography and vegetation ecology of Cuba. Akadémiai Kiadó, Budapest. 858 pp.
Borhidi, A. and Muñiz, O. (1986). The phytogeographic survey of Cuba II. Floristic relations and phytogeographic subdivisions. Acta Bot. Hung. 32 (1-4): 3-48.
Samek, V. (1973). Pinares de Cajálbana. Estudio Sinecológico. Ser. Forestal Academica de Ciencias 13: 3-56.
Authors
This Data Sheet was written by Drs Angela Leiva and Rosalina Berazain (Jardin Botanical
Nacional de Cuba, Universidad de la Habana, Carrelera del Ricio Km 35, Calabazar, Habana,
Cuba.