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Deforestation and Land Degradation in the Ethiopian Highlands: A strategy for physical Recovery
Tue, 12/01/2009 - 05:52 — TihtnaPublisher:
North East African Studies (ISSN 0740-9133) Vol. 8, No. 1 (New Series) 2001, pp. 7-26
Year:
2001
Link:
Full Title:
Deforestation and Land Degradation in the Ethiopian Highlands: A strategy for physical Recovery
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Is Eucalyptus ecologically hazardous tree species?
Tue, 12/01/2009 - 05:44 — TihtnaPublisher:
www.etff.org
Link:
Full Title:
Is Eucalyptus ecologically hazardous tree species?
Abstract:
Ehiopia’s natural forest mainly consists of broad-leaved trees often mixed with conifer species such as J. procera and P. falcutus. The natural forest of the country particularly the Juniperous-Podo-Olea forest around the capital city were depleted at faster rate for fuel and construction material. As a result the development of the capital city, Addis Ababa was threatened by a fuel wood scarcity. In 1895, Emperor Menelik II introduced Eucalyptus as a potential solution to the fuel and timber shortage. As it has been reported by Breitenbach (1961), it was a French railway engineer called Mondo-Vidaillet who established trail plantation of 15 eucalyptus species for first time in Ethiopia.
The introduction of this species was a great success. Sooner or later the planting of eucalyptus for fuel, particularly, E. globulus and E. camaldulensis was expanding in the vicinity of Addis and other small towns in the country. By the beginning of 1980s the total E. globulus plantation in the country was estimated to be 91, 000ha(Henry 1973).
It is undeniable fact that eucalyptus plantations have played and will play a tremendous role in alleviating the fuel and construction material problems of the community. Since 1960, world wide eucalyptus planting has doubled every decade. In 1990 the total area in hectares planted by eucalyptus was 7 million. In spite of this, quite a number of people express their reaction against eucalyptus planting. These adverse reactions against eucalyptus planting are based on some ecological, technical and socio- economic arguments. As it has been reported by Davidson(1989) a lot of these arguments are unfair, biased, nationalistic or emotional. Most arguments are unjustified and could also be applied to some tree species such as Gravillea robusta which has allelopathic effect on most agricultural crops and Azadricata indica which is an invasive of native woodland. It is therefore worthwhile discussing some of the arguments to have a better understanding.
Water consumption of eucalyptus
Most people think that eucalyptus consumes a lot of water more than any other tree species and agricultural crop. This misconception is untrue. There are quite a number of research results which revealed that eucalyptus is efficient water user. For instance, Davidson (1989) reported that on a “leakproof hectare” at Nekemet(with annual rainfall of 2158mm), E. saligna and E. grandis could produce 46.6 m3/ha/yr without drawing on water reserves(rainfall only) compared to 16.4, 16, 12.4 m3/ha/yr biomass production for the coniferous, acacia and broadleaf species, respectively. These figures reveal that for the same amount of water consumed eucalyptus produce higher amount of biomass which is economically profitable and acceptable.
Most eucalyptus species need on average 785 litres of water/kg of biomass produced as opposed to cotton/coffee/banana(3200), sunflower(2400), field pea(2000), cow pea(1667) soyabean(1430), potato(1000), sorghum(1000) and maize(1000) liters/kg biomass produced(Davidson 1989). The above figures show that eucalyptus species are efficient water users.
Does eucalyptus promote or pervert soil erosion?
There are two main ways to conserve soil. These are physical and biological conservation measures. Construction of check dams and bench terraces can be mentioned as some of the physical measures of soil conservation while planting tree species is a biological measure. Planting of any kind of tree species in the form of a monoculture should not be taken as the best solution to sheet or surface erosion. In state owned eucalyptus forests, eucalyptus stands are established at wider spacing particularly on gentle slop sites. Wider spacing has an advantage to let the penetration of sun rays to the forest floor which is one of the many prerequisites necessary for undergrowth development. The presence of undergrowth minimises the surface runoff. Most of the Munessa Shashemene Forest Project eucalyptus stands have favoured the natural regeneration of P. falcutus, Croton machrostatchus and many other species. The depth of the accumulated letter in the above forests are found to be on average 20-30 cm. Nevertheless, in stands near very big towns and Addis Ababa, this is not the case as a result of human and cattle perplexity. Although eucalyptus generally produces less annual litter fall(1800kg/ha/yr) compared, for example, with A. lebbeck, 5000kg/ha/yr, if all litter were not totally collected by people for fuel, it would have been incorporated into the soil system to slow down runoff and improve infiltration. As a result of litter collection the ground is left bare and exposed to soil erosion. This misconception has incorrectly attributed to the allelopathy.
In addition most of state owned forests are harvested on clear felling scheme particularly on steep slops which exposes the site for soil erosion. Eucalyptus species planted for catchment protection should be cut on selective basis.
The root system of selected species for catchment protection influence the soil binding capacity as a result of which soil erosion is checked. E. globulus, for instance, has a strong tap root and good lateral root system that makes it very reputable species for catchment protection.
Soil nutrient consumption of eucalyptus
It is very difficult task to model soil/plant nutrient cycling in any forest type. This is mainly because there are a number of environmental factors influencing nutrient replenishment from parent materials as a results of weathering. Not only that the rate of leaching is also very difficult to quantify in natural systems as the system is not closed and controllable. The nutrient consumption of fast growing species like eucalyptus species need to be well studied before wrong conclusion and recommendation is being made. As fast growing species, it seems logical and sensible if the species consumes and drains nutrient from the soil.
What matters is the economic return against the biomass produced per unit of water consumed and the management practices put in place to replenish the nutrient bank of the soil system. In fact, the presence of mycorrhizas is an advantage to most eucalyptus species which facilitates accumulation of nutrients even in poor soils. If the litter are left on the forest floor uncollected, substantial amount of nutrients may pass to the soil system. The soil nutrient levels under eucalyptus forest could also be improved by adjusting spacing and introducing leguminous planting. Mixing eucalyptus with acacia species (e. g A. nilotica which produces high amount of litter, 8000kg/ha/yr) increase the litter fall and thereby improve the soil nutrient bank.
Conclusion
From the above discussion it is apparent that eucalyptus planting is not harmful be it in ecological and financial terms. In a country such as Ethiopia where the community has no other energy alternatives and where about 90% of the annually produced wood is used for fuel, it is totally unacceptable to disfavour eucalyptus planting.
Most of the rural and urban dwellers also depend on eucalyptus planting for the production of construction poles. Eucalyptus flowers produce nectare for honeybees. Species like E. citrodora are also used for perfume and oil production(e. g. Wondo Genet Essential Oil Factory). From 600 different varieties 10 eucalyptus species are widely planted virtually in all sites and ecological zones of Ethiopia except the most arid. In most parts of the country, e. g., Hossahena and Wollayta , eucalyptus became the main stay of the community for additional income generation. Eucalyptus species are tolerant to severe periodic moisture stress, low soil fertility and fire and insect attack. These comparative advantages of the species made it part of the life of the rural people. Some indigenous species seem to have such advantages as they are adaptive to the local conditions and could be used for various purposes. The sad fact is that little is known about their growth, yield, soil nutrient/plant interaction, water consumption, silviculture and management. Foresters are challenged and confronted with such problems which they should solve in order to fill the knowledge gap and come up with more indigenous species pool for reforestation and afforestation purposes. Until such time, however, eucalyptus seem to be planted widely in Ethiopia. In conclusion, it seems that there are no profound reasons not to continue or discourage eucalyptus planting in Ethiopia.
References
Breitenbach, F. 1961. Exotic forest trees in Ethiopia. A. A. Ethiopian Forestry Association, Ethiopian Forestry Review. 2:19 - 39.
Davidson, J. 1989. The Eucalyptus dilemma. Arguments for and against Eucalyptus planting in Ethiopia. The Forestry Research Centre Seminar Note Series No. 1. A. A.
Henery, P. W. 1973. Notes on maps of the eucalyptus plantations around A. A. and the Menagesha State Forest, Ethiopia.. ODA. London. Misc. Report. 150:1-10.
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Agroforestry and Community Forestery for Rehablitation of Degraded Watersheds on the Ethiopian Highlands - 2003
Tue, 12/01/2009 - 05:36 — TihtnaPublisher:
www.etff.org
Year:
2003
Link:
Full Title:
Agroforestry and Community Forestery for Rehablitation of Degraded Watersheds on the Ethiopian Highlands - 2003
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Seed and regeneration ecology in dry Afromontane forests of Ethiopia.
Sat, 07/04/2009 - 00:51 — TihtnaPublisher:
SINET: An Ethiopian Journal of Science. Tropical Ecology 46(1): 29-44, 2005. (Copy) Interantional Society for Tropical Ecology. ISSN 0564-3295
Year:
2005
Link:
Full Title:
Seed and regeneration ecology in dry Afromontane forests of Ethiopia.
Abstract:
A series of events occur in the process of regeneration, namely flowering, seedproduction and dispersal, incorporation of seeds into the soil, seed predation or germination, seedling establishment and growth and formation of seedling banks. Forests are subjected toboth natural and anthropogenic disturbances, which disrupt the process of plant regeneration. In response to these disturbances, succession is triggered in which different plants use varying strategies to regenerate themselves. For instance, tropical forest plants regenerate from one or more pathways, namely seed rain, soil seed bank, seedling bank or advance regeneration and coppice. The objective of this paper is to present the first part of an overview of the availableinformation on seed and regeneration ecology in dry Afromontane forests (DAF) of Ethiopia. The review focuses on: (i) seed production and dispersal; (ii) soil seed banks: incorporation ofseeds into the soil, species richness and densities, spatial and temporal variation and depletion of seeds in the soil; (iii) seed dormancy and germination, requirements for seed germination: light, temperature, interaction between light and temperature, scarification, moisture and dry storage; and (iv) seedling banks, seedling survival, seedling growth and population structuresof woody plants. Thematic areas for future research are recommended.
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Chapter 4. The barleys of Ethiopia
Mon, 05/04/2009 - 02:44 — TihtnaPublisher:
IDRC (The International Development Research Centre) is a Canadian Crown corporation:
Link:
Full Title:
Chapter 4. The barleys of Ethiopia
Abstract:
Introduction
Recognized as one of the world's most ancient food crops, barley has been an important cereal crop since the early stages of agricultural innovations 8,000 to 10,000 years ago. Throughout history, barley has undergone continuous manipulation in an effort to optimize its use for human consumption and as animal feed. Barley has been used as a model organism in experimental botany, the plant of choice because of its short life cycle and morphological, physiological, and genetic characteristics. Globally, barley ranks fourth among cereal crops in both yield and acreage, after wheat, rice, and maize (Munck 1992b). With advances in food production and agriculture, major dietary shifts from barley to rice and/ or wheat have resulted in the decline in barley consumption, with the exception of societies — particularly those relying on traditional, small-scale agricultural systems — in which its use as human food has continued to the present.
The world has now "re-discovered" barley as a food grain with desirable nutritional composition including some medicinal properties. Barley breakfast foods and snacks are increasingly available, driven by recent research findings, which show that barley fiber contains beta-glucans and tocotrinols, chemical agents known to lower serum cholesterol levels (Burger et al. 1981; Anderson et al. 1991). In Ethiopia, barley is the third most important cereal crop next to teff and maize. It is the staple food grain for Ethiopian highlanders, who manage the crop with indigenous technologies and utilize different parts of the plant for different purposes.
Efforts to improve barley have demonstrated a preference for a limited number of modern, genetically uniform cultivars suited for high input agriculture, to the neglect of the various farmers'varieties, or landraces, on which a large sector of the human population has subsisted for millennia. The trend has narrowed the genetic base of the local material, leading to the gradual replacement of landraces with modern barley cultivars or of other crops such as wheat and oats. One consequence of this replacement is the loss of indigenous knowledge associated with replaced landraces. It is noted that some earlier morphotypes of Ethiopian barley (e.g., hooded barley; Bell 1965) are no longer found in cultivation. Some Ethiopian barley types (e.g., smooth awned types, hull-less types) kept at the Gatersleben gene bank in Germany (Index Seminum 1983) are not found in the country at present. Some varieties reported as abundant during the Vavilovian expedition (many naked and some rare covered forms) (Orlov 1929) could not be found in those areas (Asfaw 1988). The global trend has been to select for a few high yielding types, thus narrowing the genetic base of a crop. This trend has influenced the direction of Ethiopia's limited barley research over the past four decades. In crop genetic resources conservation efforts, Ethiopian barley has been identified as a priority crop since the 1920s, and extensive germplasm collections have been deposited in gene banks all over the world, especially in Russia and the U.S. (Orlov 1929; Ciferri 1940, 1944; Negassa 1985). Both the usefulness of barley and its high genetic and morphological diversity have rendered barley conservation a matter of top priority. This is evidenced by a long history of conservation in gene banks around the world since the 1920s, beginning formally in Ethiopia in 1976. Ex situ germplasm conservation has facilitated the preservation of the diversity present at a given point in time, but does not preserve the dynamic co-evolutionary processes that take place when landraces are continuously cultivated in their natural agroecological settings. To remedy this shortcoming, the need for complementary in situ conservation has been recommended and is under serious consideration (Feyissa 1995; Soleri and Smith 1995; Altieri and Montecinos 1993).
Scientists are currently working to improve barley using genetic engineering and other modern techniques; they are looking forward to the formulation of barley ice cream and many other fabulous products for future markets. Another area of research concentrates on alternative approaches for sustainable use and conservation of the diversity in the barley gene pool. This approach focuses on in situ conservation of barley landraces — a new line of thought rooted in the traditional practices that have preserved the indigenous farmers'varieties. Traditional farming systems have the dual functions of production and conservation since the entire agroecosystems are crop germplasm repositories (Altieri and Montecinos 1993). This chapter highlights the case of barley in Ethiopia, focusing on the importance of traditional management and cultural practices associated with the landraces. Traditional farmer practices are viewed in the light of on-farm conservation activities being implemented under a new landrace on-farm conservation project, A Dynamic Farmer-Based Approach to the Conservation of Ethiopia's Plant Genetic Resources, supported by the Global Environment Facility and implemented by the Biodiversity Institute of Ethiopia in collaboration with other institutions.
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The maize seed system in Ethiopia: challenges and opportunities in drought prone areas - 2008
Mon, 05/04/2009 - 02:29 — TihtnaPublisher:
African Journal of Agricultural Research Vol. 3 (4), pp. 305-314, April, 2008 Available online at http://www.academicjournals.org/AJAR ISSN 1991- 637X 2008 Academic Journals
Link:
Full Title:
The maize seed system in Ethiopia: challenges and opportunities in drought prone areas - 2008
Abstract:
This study examines how the performance of the maize seed system in Ethiopia affects small-scale
farmers’ access to and use of improved maize varieties. Particular emphasis is given to the droughtprone
agro-ecologies of the Rift Valley region and the specific maize varieties developed for and
disseminated in this area. Data for this study were gathered in 2005 from focus group discussions with
maize farmers across three districts in the Rift Valley; household surveys of a random sample of 60
maize farmers; key informant interviews with public and private sector stakeholders in the maize seed
market; and government and industry secondary sources. Findings show that despite extensive varietal
development by the public research system, dissemination of improved varieties to farmers remains
limited. This may be partially due to the continued dominance of public sector organizations in the
multiplication and supply of seed to farmers, and to the relatively low level of private sector
participation. The result is a seed market characterized by limited competition, insufficient supply of
seed relative to demand, limited choice in the few varieties that are available, and excessively high
costs of maize seed production. Without significant structural and organizational change to the maize
seed system, these market and institutional failures will continue to hamper smallholder access to
improved varieties developed for drought-prone regions such as the Rift Valley.
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Sowing the Seeds of Famine in Ethiopia - 2000
Tue, 03/24/2009 - 01:01 — TihtnaPublisher:
The Ecologist, 2000-09-01, Global Research, September 10, 2001
Year:
2001
Link:
Full Title:
Sowing the Seeds of Famine in Ethiopia - 2000
Abstract:
The "economic therapy" imposed under IMF-World Bank jurisdiction is in large part responsible for triggering famine and social devastation in Ethiopia and the rest of sub-Saharan Africa, wreaking the peasant economy and impoverishing millions of people.
With the complicity of branches of the US government, it has also opened the door for the appropriation of traditional seeds and landraces by US biotech corporations, which behind the scenes have been peddling the adoption of their own genetically modified seeds under the disguise of emergency aid and famine relief.
Moreover, under WTO rules, the agri-biotech conglomerates can manipulate market forces to their advantage as well as exact royalties from farmers. The WTO provides legitimacy to the food giants to dismantle State programmes including emergency grain stocks, seed banks, extension services and agricultural credit, etc.), plunder peasant economies and trigger the outbreak of periodic famines.
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Changes of Sorghum bicolor landrace diversity and farmers’ selection criteria over space and time, Ethiopia - 2007
Thu, 03/12/2009 - 21:10 — TihtnaPublisher:
Springer Netherlands. Volume 54, Number 6 / September, 2007. Genetic Resources and Crop Evolution
Link:
Full Title:
Changes of Sorghum bicolor landrace diversity and farmers’ selection criteria over space and time, Ethiopia - 2007
Abstract:
Temporal and spatial changes of sorghum landrace diversity and related factors in five farming communities in north Shewa and south Welo, between 1992/1993 and 2000/2001, were studied in order to ascertain the stability of a range of factors that support the maintenance of the crop genetic diversity. The same farmers were interviewed and the same sorghum fields were surveyed both times. Over the 8-year period: the total area planted to sorghum decreased drastically in all five farming communities and a large percentage of the farmers in the communities.
(Hayk, 69%; Borkena, 68%; Epheson, 51%; Merewa Adere, 72%; and Bati, 54%) decreased the field size planted to sorghum, because of population growth, land redistribution policy, seasonal changes, and stagger cropping followed by interspecies crop displacement; landrace richness increased significantly in Merewa and Borkena, but decreased significantly in Bati, Epheson and Hayk; and farmers’ selection criteria, the reasons for growing specific landraces, increased significantly (10 in 1992/1993 vs. 22 in 2000/2001). Significant differences in field size distribution occur among the five farming communities. In 2000/2001, 22 “generalist” landraces (grown widely across three or more communities), and 46 “specialist” landraces (niche specific, restricted to certain microhabitats in one or two communities) were found. Landrace gains and losses from the farms surveyed in individual communities over the period are demonstrated.
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Deforestation and degradation of natural resources in Ethiopia: Forest management implications from a case study in the Belete-G
Tue, 03/03/2009 - 11:17 — NES-Global WebmasterPublisher:
Springer Japan - Volume 3, Number 4 / November 1998
Year:
2006
Link:
Full Title:
Deforestation and Degradation of Natural Resource in Ethiopia Forest Mangement Implifications from a case studey in the Belete-Gera
Abstract:
The major causes of deforestation and degradation of natural resources in the Belete-Gera Forest of Ethiopia are coffee production activities and encroachment into forestland to expand farmland and pasture. Population growth, and the government’s land-reform and re-settlement programs have caused local residents to lose harmony with the land. Forest management in this area hasn’t yet been fully developed. The objectives of this study are to identify the extent of deforestation and natural resource degradation, in preparation for a sound management plan. Encroachment of farmland and pasture into natural forest during the past four years has been identified through interviews and aerial photo interpretation. The encroachment rate is 1.45% per year. Encroachment occurred mostly on areas with gentle slopes adjacent to populated villages and along roads and footpaths. The extent and impact of coffee production activities were examined through agency documents, forest survey data and vegetation survey. It is estimated that up to 49% of the accessible natural forest is under the influence of coffee production activities, among which collecting of naturally grown coffee beans has the least and the coffee plantations has the most impact on the natural forest. Coffee plantations in natural forest have reduced the forest density and species diversity. Age structure of the trees is limited to mature and old classes only, which eventually endangers their function as shade for coffee plantations.
Journal Article
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