97 SOME LOW ELEVATION FOG FORESTS OF DRY ENVIRONMENTS: A P P LICAT 1 O NS TO A F R ICAN PA LE O E NV I R O N ME N TS ALAINGIODA, JEAN MALEY, ROBERTOESPEJO GUASP, AND ANDRÉSACOSTA BALADON MACARONESIAN ELFIN CLOUD the Canary Islands harbor the richest botanical FORESTS: CANARIAN EXAMPLES diversity and most extensive remnant stands of fog/ cloud forest. We.. Dresent some examdes of cloud water and fog- precipitation on vegetation following Kerfoot's EI Hierro is the smallest island (280 km2) of the pioneer work (1 968). High fog frequency allows for Canarian archipelago (28" N;13-1 8" W) (Figure 1). the existence of forest communities.in otherwise Under an arid climate, "fountain" trees (laurels, arid (low rainfall) conditions. Using the EI Hierro junipers, pine trees) have been used for centuries to fountain tree as an example, Macaronesian elfin provide freshwater. Water is naturally collected by forests are described, with special attention to the such trees from the intense fog (niebla) that occurs Garajonay National Park (La Gomera, Canary often without any rainfall. From the leaves, the Islands) where very significant stands of fog/cloud water drops on the soil where it can be collected and forest remain. stored. One laurel tree (Ocotea foetens), the so- called Garoé, was used by the native pre-Hispanic The Macaronesian region includes the Azores, populations until 1610, when it was uprooted by a Canary, Cape Verde, and the Selvagens. Of these, hurricane (Figure 2). The following is an extract I I 1 30' 18' 14' LANZAROTE LA PALMA Roque de los M9 c ach L"Rs- na 2 8' - GRANDE CANARIE f 4 2 6'N 18'W 14' 1 FIGURE 1. Canary Islands, Spain, including the location of the Garoé and Garajonay National Park. Drafted by M. Suavin. 8 $"q p-\? p 98 GODAET AL. HIERRO FIGURE 2. EI Hierro coat of arms. The fountain tree, the so-called Garoé, is at the center of the escutcheon. This tree. which was uprooted in I610 by a hurricane. is still visible symbolically, espe- i cially o'n taxi cabs that alwa-vs carry stickers with I El Hierro's arms on their doors. FIGURE 3. Ocotea foetens, a Macaronesian laurel. The Garoé was an O. foetens. Drawn by M. Djellouli. from George Glas's History of the Discovery and Conquest of the Canary Islands (1 764): On the top ofthis rock [=1,000 m] grows a tree called, Martin, who worked with ICONA (Instituto Nacio- in the language of the ancient inhabitants, Garoé nal para la Conservación de la Naturaleza). By 1993, (sacred or holy tree), which for many years has been 48 years later, this laurel had become a new foun- preserved sound, entire and fresh. Its leaves constantly distill such a quantity of water, as is sufficient to tain tree producing high quantities of fog water like fumish drink to every living creature in Hierro; nature the ancient Garoé (Gioda et ai. 1992; Gioda, having provided this remedy for the drought of the Hemández Martin, and Gonzales 1993). The aver- island. It is disrinct from other trees, and stands by age annual rainfall is 800 mm in this El Hierro itself. The circumference of its trunk is about twelve region, according to data from Consejeria de Obras spans [l span G 72.8 cm], the diameter four, and in Publicas. height from the ground to the top ofthe highest branch forty spans: the circumference of all the branches Another famous fountain tree, a juniper (Juni- together is one and twenty feet [ 1 footr 30.5 cm]. The perus phoenicea) located at Cruz de los Reyes branches are thick and extended; the lowest com- mence about an ell [ 1 ell % 120 cm] from the ground. (1,353 m), was destroyed by a bush fire in 1990, but Its fruit resembles the acom, and tastes something like both the concrete collector under the plant and the the kemel of a pineapple, but it is sofier and more water storage system, built on behalf of Don Zósimo aromatic. The leaves of this tree resemble those of the Hemández Martin, are still in place (Acosta Baladón laurel, but are larger, wider, and more curved; they 1992). Plans have been made to transplant a new come forth in perpetual succession, so that the tree always remains green. juniper tree in this location (Gioda 1993) with the concurrence of local authorities (island government, In memory ofthe Garoé, another laurel (Ocotea ICONA), who in the 1970s and 1980s supported foetens; Figure 3) was planted in 1945 at the same construction of the concrete collector and fog wa- place as the old one by Don Zósimo Hernández ter storage tanks. Today, cattle drink fog water Smne Low Elevacicm Fog Foresls of Dry EnvironmenIs: Applications lo African Pal~.oenvircitirricnl.s 99 collected from pine trees (Pinus canariensis) on Many other Canarian cndcmic trees and shrubs Mirador de los Bascos (650 m) and on El Hierro occur in this forest, including Appollonias barbu- (Gioda, Hernández Martin, and Gonzáles 1993). jana spp. ceballosi, Ilex perado spp. lopez-lilloi (specific to La Gomera), Arhufus canariensis, Erica Besides these Canarian examples, farmers have scoparia spp. platycodon. Gesnouìna arborea, Ilex used fog water.on Brava (Cape Verde Islands) since perado SQP. platyphilla, Junipems cedrus, Mqtenus 1942, mainly collected from agaves (Furcraea canariensis, Sambucus palmensis. Teline stenope- giganfeu) and palm trees (Phoenix sp.) (Reis F. tala var. microphylla. Viburnum tinus spp. rigidum, Cunha 1964; Acosta Baladón and Gioda 1991, and Myrica rivus-murfinezii (PCrez de Pm 1990). 1992). In the Canary Islands, the evergreen forest has Garajonay National Park (La Gomera Island): vanished on Gran Canaria, where only 1 percent of A Canarian Elfin Cloud Forest the pre-Hispanic forest community still exists; and The elfin cloud forest of Mount Garajonay on La it is endangered on Tenerife where less than 1O per- Gomera Island has been classified a Spanish na- cent of this forest type remains, concentrated in the tional park since 1981 (total area: 3,985 ha). Since Montes de las Mercedes region (White 1986; Garcia 1986, it has been registered as a UNESCO World Morales 1989). Heritage site (Pérez de Paz 1990). SOUTH AMERICAN Climate and Hydrology. The Canary Islands are CLOUD COMMUNITY: THE LACHAY essentially influenced by the subtropical high NATIONAL RESERVE, PERU pressure systems ofthe north Atlantic Ocean, trade winds being the factor driving the atmospheric In 1977, the Lachay National Reserve, a woodland circulation. These winds from the NNE are humid in a very dry and foggy formation, was declared by (relative humidity 75-90 percent) and collide with the Peruvian authorities (total area 5,070 ha). It is the insular blocks, producing a "sea of clouds," the located 105 km north of Lima near the Panamerican altitude of which usually ranges from 600 to Road (1 1 " S; 77" W). It is representative of lomas 1,500 m. In the vicinity of Tenerife island, the (hill) formations located between 8" S (Peru) and average frequency of occurrence of the "sea of & 20" S (Chile). Lomas also refers to botanic forma- clouds" is 199 days per year. These clouds do not tions. In central and southern Peru, not far away result in abundant rainfall because an upper-level from the Pacific coast, many loinus such as Lachay temperature inversion restricts their vertical growth are found, with ancient pzteblos (pre-Colombian and the formation of a deep cloud layer necessary settlement ruins [Engel 19871). Their inhabitants for raindrop formation. Mount Garajonay National had preserved natural resources without any'destruc- Park (elevation 700-1,487 m) has an evergreen tive pressure by grazing and exploitation of wood. forest sustained by direct interception of cloud water. The mean annual rainfall in the area ranges Climate and Hydrology from 600 to 800 mm. It is estimated that forest fog/ Based on 44 years of observation, the climate of cloud-water interception is more than double this Lachay is characterized by the following pa- amount (Santana Pérez 1990; Gischler I99 1). rameters: (1) rainfall, 173 mm; (2) fog (gariia) precipitation under the canopy: depth of rainfall Vegetation and Flora. The laurel forest, the multiplied by 3-8; (3) monthly average tempera- so-called lazt~-isifva,is a luxuriant subtropical tures: 12.8"-20.8" C; (4) monthly average sunshine vegetation with a diverse structure of trees, shrubs, periods: 36-21 8 hours. herbs, and climbers so dense that they prevent light penetration into the forest interior. The evergreen SENAMHI (Servicio Nacional de Meteorología forest zone is dominated by four species of laurel e Nidrologia) has been working since the 1960s in (bay): L LI u rus az u ri CLI, A ppo Il o 17 ias h ar0 zija n a, the tollo\ving lutnus: Lxliay, Pasamayo, Cerro Persea indica, and Ocorea foefens. These are all Campana, Atiquipa, Cerro Orara (Ventanilla- Macaronesian endemics and relicts of a now virtu- Ancon), Cerro Colorado (Villa Maria de Triunfo), ally extinct tertiary Mediterranean flora that occu- and Parque Recreacional de Cahuide (Ate-Vitarte). pied southern Europe and North Africa about The aim of SENAMHI is to develop the use of fog 15-40 million years ago. catchers on lomas at altitudes between 400 and " .'1. k 1 O0 GIODAET AL. 1,000 m. SENAMHI obtains an average fog water 1991). However, cloud phenomena may be present production of up to 10 liters/m2/day using a mesh at distances up to 800-1,000 km from the Atlantic proposed by ESTRATUS Company. Ocean in Gabon and the Congo (Maley 199 1).