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Home , George Glas, Ilex perado, Laurel forest, Ocotea, Ocotea foetens, Podocarpus

97 SOME LOW ELEVATION FOG 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 harbor the richest botanical FORESTS: CANARIAN EXAMPLES diversity and most extensive remnant stands of fog/ cloud . We.. . Dresent some examdes of cloud water and fog- precipitation on 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 , "fountain" (laurels, arid (low rainfall) conditions. Using the EI Hierro junipers, trees) have been used for centuries to fountain 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 (, Canary often without any rainfall. From the , 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 ( foetens), the so- called Garoé, was used by the native pre-Hispanic The Macaronesian region includes the , populations until 1610, when it was uprooted by a Canary, , and the Selvagens. Of these, hurricane (Figure 2). The following is an extract

I I 1 30' 18' 14'

LANZAROTE 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, , 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 's arms on their doors. FIGURE 3. , 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 resembles the acom, and tastes something like both the concrete collector under the 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 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, 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. tinus spp. rigidum, Cunha 1964; Acosta Baladón and Gioda 1991, and rivus-murfinezii (PCrez de Pm 1990). 1992). In the Canary Islands, the forest has Garajonay National Park (La Gomera Island): vanished on Gran Canaria, where only 1 percent of A Canarian Elfin the pre-Hispanic forest community still exists; and The elfin cloud forest of Mount Garajonay on La it is endangered on 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, 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 (). 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 . 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 : depth of rainfall Vegetation and Flora. The , 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 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 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 Mediterranean flora that occu- and Parque Recreacional de Cahuide (Ate-Vitarte). pied southern Europe and North 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). All studies concerning the history of the vegeta- Vegetation and Flora tion in Africa have concluded that during climate The vegetation is characteristic of the central cooling, mountain vegetal species extended to Peruvian hills (lomas) along the desertic Pacific relatively low elevations. analyses carried out coast (Weberbauer 191 1). The most representative in eastern Africa (Bonnefille et al. 1992) and in trees are two species: tara (Caesalpina tinctoria) central and western Africa (Maley 1989, 1991) and pallilo (Capparis prisca), growing at altitudes show that temperatures dropped by 3"-8" C during ranging from 500 to 700 m. Among the trees and the last maximum about 18,000 years BP. On shrubs, the following species are vanishing in the the high mountains of east Africa, the observational lomas: Eupatorium sternbergianum. Cassia biflora, evidence of the descent of glaciers by about 1,000 Carica candicans, Lobelia decurrens, Capparis m has led to similar conclusions (Hamilton 1982). prisca, and Caesalpina tinctoria (Dourojeanni and To understand the effect of lower temperatures, we Ponce 1978). The woodland contains few succu- can examine the composition of flora and fauna at lents. The trees are scattered, gnarled, and stunted. elevations in the middle altitude range, between They are located on often skeletal soils between 1,000 and 3,000 m. For example, the percentages of rocks where are growing. The most plant species common to Mount and the abundant are the genera Pitcairnia and Puya. mountains of eastern Africa are 53 percent for mountain forests and 49 percent for mountain SOME ASPECTS OF AFRICAN meadows. Similar percentages occur for QUATERNARY PALEOENVIRONMENTS and (Moreau 1966). To explain these similari- Tropical cloud forests help us to understand some ties, many authors have ventured that during the paleoenvironmental paradoxes, such as lowland coldest periods of the Quaternary, mountain flora extensions of mountain ecosystems during Quater- and fauna have spread to low altitudes, thus allow- nary Ice Ages. The mountain ecosystems generally ing migrations between mountain ranges. Indeed, appear above 1,000 m. However, in tropical Africa pollen analyses for location sites far away from high we find today several lowland spots with mountain mountains have supported this assumption. For ecosystems, for example, on the southem border of example, a small depression at 600 m (Bois de the Zaire-, in the Mayombe, Chaillu, Bilanko, about 35 km north of Brazzaville, Congo) . and Monts de Cristal hills (White 1981; Maley has yielded a section with pollen types dominated Caballé, and Sita 1988) or in other areas such as the (before the beginning of the Holocene) by mountain Freetown hills (Liberia), Mount Cameroon, the species: Iatijolius (50 percent), Ilex Angola plateau, and Mount Usambara (Maley mitis, and Olea capensis, constituting 60 percent of 1989). Outside Africa, there are many examples of the pollen spectra. Moreover, between the mountain this phenomenon in the Antilles and around the ranges of eastern Africa and Cameroon, isolated Sea (Baynton 1968; Howard 1970). In the occurrences of species typical of mountain areas still northern tip of , Cavelier and Goldstein exist today (Maley, Caballé, and Sita 1988). These (1 989) described the elfin forest of the Serrania de are benchmarks on a preferenrial path of migration, Macuira, which occurs at a maximum elevation of which probably operated intermittently during the 865 m. coldest periods of the Quaternary, or before the Quaternary. This path joins eastern Africa to In fact, such communities can be found at eleva- Angola, and through the hills of Mayombe, Chaillu, tions as low as 500 m, or even 300 m (Ango1a):They and Monts de Cristal, it reaches the mountains of can occur on lower slopes of high mountains (Mount Cameroon (Maley 1989, 199 1). Cameroon, 4,070 m) (Serle 1964; Thomas 1986), on plateau escarpments (Angola, ), or on hilltops as a result of crest effects (Peru, Chile). These communities are particularly numerous near the sea (Moreau 1966; Kerfoot 1968;'Whitmore 1975; Blot Some Low Elevalion Foy Fores& of Dr?,Environments: Applicalions 10 Afiican Pa1eoenvironmcnf.s 101

ACKNOWLEDGMENTS Glas, G. 1764. Descripcihn de lus Islus Canurius 1764. SIC. Tenerife: Instituto de Estudios Canarios-Goya Ediciones, We thank the Spanish ICONA staff, the Chilean CONAF 2nd ed., 1982 (in Spanish from the British original (Corporación Nacional Forestal) team, Dr. Luis Acosta Alvarez version). (head ofthe Peruvian SENAMI-II), and Pierre Pourrut (Orstom- Antofagasta) for their contributions. Comments by Pierre I-tamilton, A.C. 1982. Environmentul history ofEust Africa. A Fontanel, Edouard Lclloc’h (CNRS, and Riseau Zones study í/ihr Quuternury. London: Academic Press. Arides- MAB France-Montpellier), and Yann L’Hôte Howard, R.A. 1970. The “Alpine” of the Antilles. (Orstom-Montpellier) helped in the preparation of the paper. Biotropicu 224-28. The Cameroonian program on lowland and mountain forests results from collaboration ofseveral Cameroonian scientific in- Kerfoot, O. 1968. Mist precipitation on vegetation. Forestry stitutions (MESIRES, ISH, CGM, CRH, IRGM, University of Abstracts 293-20. Yaoundé). Also, the EEC helped with research on Spanish Maley. J. 1989. Late Quaternary climatic changes in the African organisms (Comett-II: Prof. André Van der Beken). The rain forest: Forest refugia and the major role ofsea surface fountain tree project of Cruz de los Reyes (EI Hierro, Canary temperature variations. In M. Leinen and M. Sarnthe, Islands) is supported by the 1993 Rolex Awards for Enterprise editors, Paleoclimatologyand Paleometeorology: Modem (Selected Projects in Environment). and past putterns ofglobal atmospheric Irunsport, pages 585-6 16. Dordrecht, the Netherlands: Kluver, NATO Adv. REFERENCES Sc. Inst., Series C, Math. and Phys. Sc., 282. Acosta Baladón, A. N. 1992. Niebla potable. Conciencia Maley, J. 1991. The African rain forest vegetation and Pluneruria 12:50-55. paleocnvironmcnts during late Quaternary. Climatic Change 19:79-98. Acosta Baladón, A. N., and A. Gioda. 199 I. L’importance des précipitations occultes sous les tropiques secs. SGcheresse Maley, J., G. Caballé, and P. Sita. 1988. Etude d’un peuplement 2(2): 132-135. résiduel a basse altitude de Podocorpus latifolius sur le Acosta Baladón, A. N., and A. Gioda. 1992. Las precipi- flanc congolais du massif du Chaillu. In R. Lafranchi and taciones ocultas y la desertificación. In Encuentro Meteo D. Schwartz, editors, Paysages quaternaires de 1 ‘Afrique 92, II:370-374. Madrid: Instituto de Meteorología centrale atlantique, pages 336-352. Paris: Orstom, série Española. Didactiques. Baynton, 1968. The ecology ofan elfin forest in Puerto Moreau, R.E. 1966. The birdfaunas $-Africa and its islands. H.W. New York: Academic Press. Rico. 2. The microclimate of Pico del Oeste.Journa1 of the Arnold Arboretum 49(4): 4 19-430. Pérez de Paz, P.L., editor. 1990. Parque Nacional de Gara- jonay. Blot, J. 1991. Bilan écologique des forêts 6 Juniperus procera Madrid: ICONA. de la corne orientale de l’Afrique et de la péninsule Reis F. Cunha. 1964. O problema da captacão de água do arabique. Thèse, Université de Bordeaux III, France. nevoeiro em Cabo Verde. Gurcia de Orta fLisboa) 12(4): Bonnefille, R., F. Chalié, J. Guiot, and A. Vincens. 1992. 71 9-756. Quantitative estimates of full glacial temperatures in Santana Pérez, L. 1990. La importancia hidrológica de las equatorial Africa from palynological data. Climuric nieblas en las cumbres del Parque Nacional de Garajonay. Dynumics 6:25 1-257. In P. L. Pérez de Paz. editor, Parque Nacional de Gara- Cavelier, J., and G. Goldstein. 1989. Mist and fog interception jona-v. pages 67-71. Madrid: ICONA. in elfin cloud forests in Colombia and . Journal Serle, W. 1964. The lower altitudinal limit of the montane of Tropical Ecology 5:; 09-3 22. forest birds in the Cameroon mountains, .

Dourojeanni, M.J., and C.F. Ponce. 1978. Los Parques Bulletin of lhe British Ornithological Club 8437-9 1 ~ Nacionales del Perii. Madrid: INCAFO. Thomas, D.W. 1986. Vegetation in the montane forests of Engel, F.E. 1987. De las begonias al maiz. Vida y produción Cameroon. In S.N. Stuart, editor, Conservaiion of Cam- en el Perii antiguo. Lausanne: CIZA. eroon montaneforests, pages 20-27. Cambridge: Report of Intern. Council Preserve. Garcia Morales, M. 1989. El bosque de laurisilva en la economía guanche. SIC. Tenerife: ACT, 12. Weberbauer, A. 19 1 I. Die Pflanzenwelt der peruanischen Anden. XII, Leipzig: Wilhelm Engelmann (2nd ed., 1976. Gioda, A. 1993. A new fountain tree for Hierro (Canary Vaduz, Leichtenstein: Gantner). Islands.). In The Spirit for Enterprise: The I993 Rolex Awards. Bem: Buri Intemational. White, F. 1981. The history of the archipelago and the ,scientific needs of conservation. African Journal Gioda, A., A. Acosta Baladón, P. Fontanel, 2. Hernández of Ecolo~y19~33-54. Martin. and A. Santos. 1992. L’arbre fontaine. La Recher- che23(249): 1400-1408 (EI árbol fuente. Mundo Cientijìco White, F. 1986. La vkggdfafionen Afrique. Paris: Orstom- 1993, 1311321: 126-134). Unesco. Gioda, A., Z. Hernandez Martin, and E. Gonzáles. 1993. Whitmore, T.C. 1975. Tropical in the Far Easf. Observatoires, brouillards et arbres fontaines aux Canaries. Oxford: Clarendon. Submitted Veille Climatique Satellitaire. 46 = 3 8 - 49. Gischler. Ch. 199 I. The missing link in u production chain. Montevideo, Uruguay: Unesco-Rostlac. Tropical Montane Cloud Forests Proceedings of an International Symposium TROPICAL MONTANE CLOUD FORESTS

Proceedings of an Intemational Symposium at San Juan, 31 May-5June1993

Compiled and Edited by

Lawrence S. Hamilton East-West Center

James O. .Juvik University of Hawai'i, Hilo

and

Fred N. Scatena International Institute of Tropical Forestry

1993

I International Hydrological Programme Intemational Institute of Tropical Forestry