Ethiopian Environment and Forest Research Institute

Addis Ababa, Ethiopia

Ethiopian Environment and Forest Research Institute

Addis Ababa, Ethiopia
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Derero A.,Ethiopian Environment and Forest Research Institute | Tesfaye G.,Ethiopian Environment and Forest Research Institute | Woldemariam Z.,Ethiopian Environment and Forest Research Institute
Journal of Forestry Research | Year: 2017

Cordia africana is a very important indigenous tree species for timber and other products and services in Ethiopia. Seed traits and seedling vigour of seeds from 12 provenances of the species were compared. Mean seed mass for each provenance was assessed for 1000 seeds in 10 replications, and seed length and width were measured for 100 seeds in four replications per provenance. Germination was assessed in a glasshouse taking 400 seeds from each provenance. Root collar diameter and height of 440 seedlings grown in a nursery for 290 days in Addis Ababa were measured. Seed length, seed width, seed mass, and shoot height and root collar diameter of seedlings showed significant differences (P < 0.001) among provenances. Correlation analysis between seed and seedling traits and environmental variables revealed significant positive correlations between seed width and germination percentage, seed width and altitude, seed width and longitude and seed length and latitude. Negative correlations were obtained between seed width and temperature, seed width and rainfall, seed mass and temperature, and germination and temperature of the seed source. As expected, differences in seed trait did not explain the variability in seedling vigour. Determining quantitative variations in seed traits and seedling vigour among provenances and the patterns along environmental gradients are essential for informing decisions on the tree improvement programme of the species. © 2017 Northeast Forestry University and Springer-Verlag Berlin Heidelberg

Lemma B.,Mekelle University | Kebede F.,Ethiopian Environment and Forest Research Institute | Mesfin S.,Mekelle University | Fitiwy I.,Mekelle University | And 2 more authors.
Environmental Earth Sciences | Year: 2017

The loss of soil from land surfaces by erosion is widespread and reduces the productivity of agricultural lands. Concurrently, due to increasing human population, agricultural land expansion and exploitation, soil erosion and nutrient loss are the major environmental problems in Ethiopia. This study was conducted to estimate annual losses of soil, soil nutrients and carbon due to rill erosion. The entire watershed was classified into 12 land mapping units (LMUs). Consequently, the cropland was delineated to estimate soil and nutrient losses. Dimensions of the rills were measured at different parts of the landscape, and rill volume of rill erosions was assessed in the field. Disturbed representative composite soil samples were taken from each LMU to estimate the main soil nutrients, and each soil nutrient was estimated using different methods. The result revealed that the amount of soil lost through rill erosion was found to be 3.17 t ha−1 year−1. The average annual nutrient loss by the rill erosion was 41.4 kg ha−1 soil organic matter content, 2.4 kg ha−1 total N, 0.02 kg ha−1 available P and 0.3 kg ha−1 exchangeable K. The annual estimated cost of the soil nutrient lost (total N and available P) due to rill erosion was found to be 1341 USD. This cost would be used to replace the total N and available P nutrients lost through the addition of mineral fertilizers. Water erosion in the form of rill erosion was severely affecting soil fertility management and crop production in the study watershed. Hence, effective integrated watershed management interventions and farmland managements could combat soil erosion. © 2017, The Author(s).

Yirgu A.,Central Ethiopia Environment and Forest Research Center | Manjur B.,Mekele Environment and Forest Research Center | Haile A.,Mekele Environment and Forest Research Center | Girmay T.,Mekele Environment and Forest Research Center | And 3 more authors.
African Entomology | Year: 2017

Cordia africana grows in the Middle East and Africa. It is a multipurpose tree with several groups of insect pests that affect the seeds, fruits and leaves of this species. The aim of this study was to identify the causative agent responsible for leaf defoliation in Raya Azebo District and Wondo Genet College of Forestry and Natural Resource in Ethiopia. Two leaf defoliators viz. Dictyla poecilla and Compseuta brevicarinata were found associated with leaves of C. africana that were raised in Facha Gama Research Station and Wondo Genet, respectively. The insects were limited to different geographical areas and higher rate of defoliation was recorded in Facha Gama than in Wondo Genet. This is the first report on C. africana hosting D. poecilla and C. brevicarinata. © 2016 Entomological Society of Southern Africa.

Amare E.,Addis Ababa Institute of Technology | Kebede F.,Ethiopian Environment and Forest Research Institute | Mulat W.,University of Connecticut
International Journal of Environmental Science and Technology | Year: 2017

The present study monitored textile factory, distillery, and domestic wastewaters and investigated the effects of blending on the physicochemical properties of these wastes. Findings revealed that distillery wastewaters had the highest values of all tested parameters, including heavy metals, biodegradable organics, and nutrients. Biological and chemical oxygen demands in the textile wastewater were higher than domestic wastewater, while total phosphorus, total nitrogen, and sulfate were higher in the domestic wastewater. Likewise, while higher mean concentrations of zinc, copper, iron, and manganese were found in the domestic wastewater, the rest studied heavy metals did not show statistical differences (p < 0.05). This study concluded that blending improves biological treatability and effectively neutralizes the alkaline textile, acidic distillery, and domestic wastewaters at volumetric ratios of 3:1:18, respectively. This methodology will help to avoid the use of chemicals for neutralization and can be a useful entry point to establish sustainable wastewater management strategy in the developing countries. The results suggest the need for inclusion of the tested nine heavy metals in the Ethiopian standards for discharge from the distillery and domestic effluents. © 2017, Islamic Azad University (IAU).

Fikir D.,University of Gondar | Tadesse W.,Ethiopian Environment and Forest Research Institute | Gure A.,Hawassa University
International Journal of Forestry Research | Year: 2016

The study was conducted in Hammer district, Southern Ethiopia, to provide empirical evidence on economic contribution to local livelihoods and households dependency on dry forest products. One agropastoral and two pastoral kebeles were purposively selected, and data was collected through household survey, group discussions, market assessments, and field observation. A total of 164 households, selected based on a random sampling procedure, were interviewed using structured questionnaire. The study found that income from forest products contributes 21.4% of the total annual household income. The major dry forest products include honey, fuel wood, gum and resin, and crafts and construction materials, contributing 49%, 39%, 6%, and 6% of the forest income, respectively. Households of the pastoral site earned more forest income and were relatively more dependent on forest products income than those in the agropastoral study site. Significant variation was also found among income groups: households with higher total annual income obtain more forest income than those with lower income, but they are relatively less dependent on forest products than the lower counterpart. Besides, various socioeconomic and contextual factors were found to influence forest income and dependency. The findings of the study provide valuable information up on which important implications for dry land forest development and management strategies can be drawn. © 2016 Dagm Fikir et al.

Iiyama M.,Research Strategy Office | Iiyama M.,International Center for Research in Agroforestry | Neufeldt H.,International Center for Research in Agroforestry | Njenga M.,International Center for Research in Agroforestry | And 6 more authors.
Frontiers in Environmental Science | Year: 2017

The production of charcoal is an important socio-economic activity in sub-Saharan Africa (SSA). Charcoal production is one of the leading drivers of rural land-use changes in SSA, although the intensity of impacts on the multi-functionality of landscapes varies considerably. Within a given landscape, charcoal production is closely interconnected to agriculture production both as major livelihoods, while both critically depend on the same ecosystem services. The interactions between charcoal and agricultural production systems can lead to positive synergies of impacts, but will more often result in trade-offs and even vicious cycles. Such sustainability outcomes vary from one site to another due to the heterogeneity of contexts, including agricultural production systems that affect the adoption of technologies and practices. Trade-offs or cases of vicious cycles occur when one-offresource exploitation of natural trees for charcoal production for short-term economic gains permanently impairs ecosystem functions. Given the fact that charcoal, as an important energy source for the growing urban populations and an essential livelihood for the rural populations, cannot be readily substituted in SSA, there must be policies to support charcoal production. Policies should encourage sustainable technologies and practices, either by establishing plantations or by encouraging regeneration, whichever is more suitable for the local environment. To guide context-specific interventions, this paper presents a new perspective-the charcoal-agriculture nexus-aimed at facilitating the understanding of the socio-economic and ecological interactions of charcoal and agricultural production. The nexus especially highlights two dimensions of the socio-ecological contexts: charcoal value chains and tenure systems. Combinations of the two are assumed to underlie varied socio-economic and ecological sustainability outcomes by conditioning incentive mechanisms to affect the adoption of technologies and practices in charcoal and agriculture productions. Contrasting sustainability outcomes from East Africa are presented and discussed through the lens of the charcoal-agriculture nexus. The paper then concludes by emphasizing the importance of taking into account the two-dimensional socio-ecological contexts into effective policy interventions to turn charcoal-agriculture interactions into synergies. © 2017 Iiyama, Neufeldt, Njenga, Derero, Ndegwa, Mukuralinda, Dobie, Jamnadass and Mowo.

Derero A.,Ethiopian Environment and Forest Research Institute | Worku A.,Ethiopian Environment and Forest Research Institute | Kassa H.,Center for International Forestry Research
Journal of Forestry Research | Year: 2017

Rapid changes in land-use in the Combretum–Terminalia woodlands of northwestern Ethiopia are mainly due to the increases in commercial farming and immigration. We used integrated ecological and social data collection techniques, including subdivision of the vegetation zone, vegetation survey, focus group discussions and key informant interviews, to identify genecological zones and set criteria for selection of viable populations of Boswellia papyrifera (Del.) Hochst in Ethiopia for conservation. Interviews of senior experts were supported with a rating method and involved 43 respondents and focused on identifying and weighting criteria and indicators of selection in a participatory way to prioritize populations for conservation. Using mean annual rainfall data, we reclassified the Combretum–Terminalia woodland vegetation region into three moisture zones (wet, moist and dry), and designated them as genecological zones for B. papyrifera conservation. A total of 35 woody species were identified at Lemlem Terara site in Metema district, and the Shannon diversity index and evenness were 2.01 and of 0.62, respectively. There were 405 adult trees, and 10 saplings and 3314 seedlings per ha. The trees were medium-sized with overall mean diameter at breast height (dbh) of 16.9 (±9.5) cm. Seedling recruitment was poor due to grazing, crop production and fire incidences. Through a multi-criteria decision analysis, five criteria and 20 quantitative indicators were identified and weighted to prioritize populations for conservation. These criteria in their descending order of importance are (1) forest ecosystem health and vitality, (2) forest cover and population structure of B. papyrifera, (3) productive function of the forest, (4) biological diversity in the forest, and (5) socioeconomic benefits of the forest to communities. Multivariate tests in the general linear model revealed significant differences among researchers and nonresearchers in rating the criteria and indicators, but not among foresters and nonforesters. Hence, participatory multi-criteria decision analysis should involve people from various institutions to rectify decisions on conservation of the species. Careful evaluation of the investment policy environment and engaging those government bodies that are responsible to allocate the dry forests for commercial farming is recommended before the proposed criteria are applied to select populations for conservation, thus ensuring subsequent use of the outcomes of such exercises and better reconciling conservation and agricultural production increment goals. © 2017 Northeast Forestry University and Springer-Verlag GmbH Germany

Yonas G.A.,Bahir Dar University | Shimelis E.A.,Addis Ababa Institute of Technology | Sisay A.F.,Ethiopian Environment and Forest Research Institute
LWT - Food Science and Technology | Year: 2016

The objective of this work was to evaluate the effect of processing factors on butter yield and mineral concentration of Shea butter (Vitellaria paradoxa) subspecies nilotica extracted using screw expeller. The significant effect of conditioning duration (CD), kernel moisture content (MC) and die temperature (DT) were investigated by a 33 full factorial design combined with response surface methodology. Butter yield, fines particles (foot), Ca and Zn concentration were selected as response variables. The model enabled to identify the optimum operating settings (MC = 6.5 g/100 g w.b and DT = 65.5 °C) for maximize butter yield, under which it predicted 42.05 g/100 g d.w. While considering other response, in allover optimization, CD of 30 min, MC of 9 g/100 g w.b and DT of 65 °C were obtained. © 2015 Elsevier Ltd.

Gezahegn Y.A.,Bahir Dar University | Emire S.A.,Addis Ababa Institute of Technology | Asfaw S.F.,Ethiopian Environment and Forest Research Institute
Food Science and Nutrition | Year: 2016

The quality of Shea butter is highly affected by processing factors. Hence, the aim of this work was to evaluate the effects of conditioning duration (CD), moisture content (MC), and die temperature (DT) of screw expeller on Shea butter quality. A combination of 33 full factorial design and response surface methodology was used for this investigation. Response variables were refractive index, acid value, and peroxide value. The model enabled to identify the optimum operating settings (CD = 28–30 min, MC = 3–5 g/100 g, and DT = 65–70°C) for maximize refractive index and minimum acid value. For minimum peroxide value 0 min CD, 10 g/100 g MC, and 30°C were discovered. In all-over optimization, optimal values of 30 min CD, 9.7 g/100 g MC, and 70°C DT were found. Hence, the processing factors must be at their optimal values to achieve high butter quality and consistence. © 2016 The Authors. Food Science & Nutrition published by Wiley Periodicals, Inc.

Dedefo K.,Arsi University | Derero A.,Ethiopian Environment and Forest Research Institute | Tesfaye Y.,Hawassa University | Muriuki J.,International Center for Research in Agroforestry
Forests Trees and Livelihoods | Year: 2016

Most tree nurseries in Ethiopia overemphasize mass seedling production to the expense of seedling quality. The study aimed at evaluating nursery characteristics and tree seed procurement approaches, and how these influenced seedling quality in eight purposively selected Woredas of Oromia region. A total of 169 respondents from government and non-government organizations, farmer nursery owners and development/extension agents and officers were interviewed. Seed quality was explored through assessing the seed supply sources, the type of seed source and mother tree selection, and the practices in seed physiological quality assessments. Our results revealed that over half (62.5%) of the nurseries were government owned, while 20% were NGO-run nurseries and the remaining 17.5% were owned by farmers. Nine challenges constraining tree seedling production and leading to underperformance were identified, with the two major problems shared by all nursery types being lack of sufficient material and germplasm input and using seeds of low or unknown quality. Informal seed dealers were the main source of seeds (87.6%) for all the nursery types. On the other hand, nursery operator’s own seed collection was from any free-standing trees either planted or retained as these sources were easily accessible. Seeds were, on average, collected from few mother trees, implying a high probability of sourcing seeds of narrow genetic diversity. Analysis of variance revealed statistically significant differences in seedling germination among the different seed procurement approaches within the same seed type. The seeds obtained from formal seed dealers had the highest germination rates in both hard-coated (87.3%) and soft-coated (79.7%) seeds. Our findings suggest that there is need to improve the seed procurement and the seedling supply system through quality assurance of the seeds used in seedling production. © 2016 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group

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