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"In this massive African continent, with its rather low altitudes, Ethiopia is a fortress – a land all of its own. On a giant bedrock of heavily seated, powerfully muscled, volcanic terraces, a forest of strange turret-shaped mountain tops, rising up to 5000 metres, are covered with persistent snow and fields of hailstones." (René Pilou, Revue des Deux Mondes, April 1901). These highlands are indeed far from tropical, often cold et sometimes very damp; they constitute nearly 45% of Ethiopia's total area, host over 85% of its population (64 million) and are the source of a number of great rivers: the Blue Nile, Awash and Omo.
Mountainous Ethiopia is split diagonally by a vast and deep furrow that widens out to the north: the Rift Depression. This major fracture of the Earth's crust, with its intensive tectonic activity, descends from Lake Nyassa to the Red Sea. At the foot of the country's steep bordering cliffs, lie vast depressed landscapes whose tropical climates can be torrid, and which are strewn with highly mineralised lakes. Sharp, repeated topographic contrasts range from 100 m below sea-level and altitudes of 4,600 metres: this unique configuration conditions Ethiopia's local climates, hydrography, vegetation and fauna, as well as its human societies and the activities they have developed throughout history.
To describe Ethiopia's environment, the master words are: diversity, contrasts and originality. These terms evoke the land's natural components as well as the way human societies have used them. The country offers a rather complete collection of all the types of ecosystems found on the African Continent. Thus it represents a sort of conservatory for many natural elements and human practices that have practically disappeared in other areas. The international community has shown considerable interest for nature in Ethiopia: its different ecosystems have been grouped into two biodiversity hotspots: the "Horn of Africa" for the lowlands; the "East-African mountainous arc" for the highlands.
Ecosystems
Ethiopia comprises some ten major ecosystems, characterised by their vegetation. On the highest mountain tops, above 3,500 meters, everlasting flower bushes, moor-lands with briars, alpine meadows strewn with clovers, as well as giant Kniphofia et de Lobelia specimens are emblematic of Afro-Alpine ecosystems, famous for their endemic flora and fauna (the Abyssinian wolf, Nyala antelope...) Around 3,000 meters, grow superb dry mountain forests, dominated by conifers and olive-trees: on the densely inhabited plateaus, they are increasingly replaced by low, bushy plant populations – mountain thickets with a wealth of woody species (Rhus, Carissa, Dodonea…). In the more humid south-western areas, this altitude level is sometimes covered by bamboo forests (Dorze, Gamo) but, more frequently, by coffee forests. Populated with large-leaved plants (fig trees, Dracaena, Milletia), its underbrush hosts tree ferns, kororima pepper and wild varieties of Coffea arabica – a species which originated from this region.
Ethiopia's lowlands display ecosystems with more usual tropical features. They host all of the classic big African mammals: zebras, giraffes, antelopes, lions, etc. On the edges of the Rift Valley, cascading hillsides descend from the plateaus: they are the kingdom of savannah woodland dominated by Combretaceae (Combretum and Terminalia). The lower strata of these hills, with their perennial high herbs, are periodically subject to dry season fires. The vast plains at the bottom of the Depression, particularly around the Great Lakes, are covered by a low, dry forest, well known for its umbrella-shaped acacias and large desert cactus-like, candle-shaped euphorbia. The drier hills host a low, entangled cover of bushy Acacia and Commiphora, the myrrh-producing trees. To the north and the east, on the lands of Afar and Ogaden, the vegetal cover becomes more sparse and scattered throughout desert ecosystems strewn with Acacia, Commiphora and Boswellia (the famous "incense trees"). Last, the banks of great rivers, the swampy areas and lake shores host aquatic ecosystems: gallery forests and palm groves, water nympheas, bull rushes and reeds, with a highly diversified avifauna.
The transition from temperate to tropical, or dry to humid, climates can occur over very short distances. Thus, in terms of biodiversity, while it does not compare with inter-tropical regions of the tropical humid forest zone, Ethiopia ranks as an important natural wildlife reserve in the planet's biosphere. Its main asset is a high rate of endemism, related to its contrasted situations, isolates, and ground irregularities. Recent surveys estimate at 3,500 the number of superior plant species in Ethiopian flora (including 300 trees and 10 to 12% endemics). The inventory of inferior plants (Briophyta, Pteridophyta, algae, etc.) has not yet been completed. In terms of fauna species and numbers, the most reliable evaluations state 860 bird species (18 endemics), 277 mammal species (35 endemics, mainly mountain animals such as the famous gelada and goureza monkeys), 201 reptiles (10 endemics) and 63 batrachians (34 endemics).
Cultural Diversity and Agrobiodiversity
Local human societies have long exploited the natural wealth of Ethiopian ecosystems and their numerous endemic wildlife species. The country's cultural diversity is remarkable: over 80 spoken languages, multiple religions, a wide variety of social and political organisations, and of populations – ranging from the sedentary tribes of the highlands to the great nomads of the Rift Valley. Nowadays, 85% of the country's inhabitants are still rural and live off the land. Agriculture and cattling are combined in many ways with food gathering, hunting and fishing. Such patterns were created when dense and often very ancient human settlements encountered this outstanding wealth of natural resources (indigenous, endemic as well as introduced). Depending on their location and culture, human groups have specialised at a given altitude (for example, the highland Amharas, or the lowland Afars) or have, on the contrary, developed strategies to adapt to mountain as well as valley environments (like the Konsos).
Since immemorial times, Ethiopian societies have been able to deploy original techniques, to select plant varieties and to develop unique productions. No wonder Ethiopia offers such outstanding agri-biodiversity. The country is one of the 12 world centres where domestic plant species originated and were differentiated. It was the cradle of many cultivars currently grown throughout the world: sorghum, wheat, barley, green peas, field peas, chick peas, sesame, safflower, Arabica coffee, khat, castor oil... Many plants are exclusively cultivated in Ethiopia: noug, enset, some tubers... Garden species are abundant (over 700), and horticultural gardens show highly original and varied patterns and compositions – which reflect social and cultural differences within the country.
Ethiopia is also a great cattle-raising land: 40 million bovines (zebus from local races): Boran, Fogera, Horro, Sheko, Abigat…), 50 million goats and sheep, 5 million donkeys and mules. It is the world leader in dromedary raising (2.3 million specimens of this famous "one-hump camel" provide milk and meat). 4 million beehives enable the country to produce and process varied and refined types of honey.
The Dangers of Evolution
The amazing wealth of Ethiopia's natural resources should not occult current threatening developments. As elsewhere in the world, population growth, increasing needs, industrialisation, intensified production and environmental ravages (desertification, mountain soil erosion and floods) are modifying local ecosystems and farming systems. Expanding agriculture, fires and intensified cattle raising tend to eliminate natural forests, which are replaced by exotic plantations: eucalyptus, cypress and acacias from Australia. The global trend is to flock down to the lowlands: as a result, big mammals become scarce. In the mountains, intensive farming takes over and reduces traditional gardening activities. The share of coffee plantations in national production is on the rise. While 14% of the country's total area enjoys a natural reserve status (a rate well above the world average), and in spite of the fact that Ethiopia has signed most major international environmental treaties – including the Convention on Biological Diversity – local wildlife is not always sufficiently protected and domestic biological resources require further and more radical measures in terms of preservation and sustainable use. To this purpose, Ethiopia has created strong institutional instruments such as the Institute of Biodiversity Conservation and Research (IBCR) and the Environmental Protection Authority (EPA). These entities are progressively designing new management tools and new governance models.
For further information :
- IBC website: www.telecom.net.et/~ibcr
- EPA website: www.epa.gov.et
- Convention on Biological Diversity website: www.biodiv.org/reports. Ethiopia : Third National Report.
- Edwards S. et al., 2000-2007- Flora of Ethiopia and Eritrea. National Herbarium, Department of Systematic botany. Addis Ababa- Upsala, 6 volumes déjà parus.
- Engels J.M. M., J.G. Hawkes & Melaku Worede, eds., 1991.- Plant Genetic Resources of Ethiopia. Cambridge University Press, 383 p. |
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