Effect of Tillage and Fertilizer Practices on Sorghum Production in Abergelle Area, Northern Ethiopia

Sorghum (Sorghum bicolor L. Moench) production is mainly constrained by soil water and nutrient deficits in northern Ethiopia. The aim of this research was to evaluate the effects of tillage and fertilizer practices on productivity of two sorghum varieties in Abergelle area, northern Ethiopia. The experimental design was split-plot design. The main-plot treatments included five tillage practices. These were shilshalo (traditional ridge without ties) for broadcasted planting (SBP), tied-ridging at planting (TR0WAP), tied-ridging at four weeks after planting (TR4WAP), zero tillage (ZT), and shilshalo for row planting (SRP). Two fertilizer rates of nitrogen (N) and phosphorus (P), as0-0 N-P ha-1(without fertilizer, F1) and 32-10 kg N-P ha-1 (with fertilizer, F2) treatments, were used in the sub-plots. The local sorghum varieties i.e., Woitoziraand Chibal (Sorghum bicolor L. Moench) were tested for two years (2002-2003). The pooled and yearly-basis data analysis showed that the main and interaction treatment effects were significantly (P ≤ 0.05) influenced the yield and yield components of both varieties. This study also demonstrated sorghum yield increment by 7 to 48% due to the interaction effect of TR0WAP with F2 as compared to the interaction effects of the other tillage treatments with F2. However, the increment of yield and yield components due to the tied-ridging and fertilizer interaction effects were higher for Chibalas compared to Woitozira. The mean sorghum crop yield due to TR0WAP interaction with F2 for Chibal was 1.45 t ha-1 and that of Woitozirawas 1.31t ha-1. Thus, suitable time of tied-ridging integrated with proper rate of fertilizer should be adopted for effective increase of crop production in the semi-arid areas of northern Ethiopia such as the Abergelle area.Keywords: Abergelle area, Fertilizer, Sorghum varieties, Tied-ridging, Tillage practices, Northern Ethiopi

Estimating Soil Bulk Density and Total Nitrogen from Catchment Attributes in Northern Ethiopia

Even though data on soil bulk density (BD) and total nitrogen (TN) are essential for planning modern farming techniques, their data availability is limited for many applications in the developing word. This study is  designed to estimate BD and TN from soil properties, land-use systems, soil types and landforms in the Mai-Negus catchment, northern Ethiopia using stepwise multiple regression (SMR) and generalized linear model (GLM) analyses. Different soil properties and other catchment attributes were collected following a standard procedure. The SMR analysis showed overall model coefficients of determination (R2) of 0.91 and 0.89 with significant F-statistics for the relationships of BD and TN, respectively, with soil properties, land-use and landforms. In addition, the GLM analysis resulted in an overall R2 of 0.92 with significant F-statistic for BD, and an R2 of 0.94 with significant F-statistic for TN. The model coefficients of both analyses for the dependent variables showed higher for organic carbon (OC) as compared to the other variables even though higher values were found from GLM. This study thus confirmed that practices which improve OC can strongly influence the variation of both dependent variables. This study suggested that BD and TN should be estimated based on the  relationships explained by the different techniques (analysis) in similar conditions in order to improve data availability; however, the GLM is preferable as it considers the effect of the interaction terms.Keywords: Bulk density, Total nitrogen, Stepwise multiple regression, Generalized linear model, Mai-Negus catchment

The Role of Cooperatives In Unlocking Potentials of People with Disability: The Case of Tigray War Veterans in Mekelle

This study presents analysis of the role of cooperatives in unlocking the potentials of disabled war veterans. Veterans are indeed interested to join themselves in a genuine synergy under cooperatives to solve their social and economic problems. The ultimate objective of this thesis was to assess and measure the overall role of cooperatives in unlocking potentials of the disabled veteran through cooperatives, and in attaining social and economical empowerment of people with disabilities. To find out the role of cooperatives in attaining sustainable livelihood of the veterans engaged in cooperatives, by the degree of physical, human, social, and financial capital they owned; To examine the role of cooperatives in improving the lifestyle, self image and attitude; To identify the challenges encountered by the disabled members of the cooperatives; To assess the compatibility of the cooperative units (activities) to people with disabilities and to suggest future directions for all-inclusive policy and interventions. Data was collected from primary & secondary sources through structured & unstructured personal interview, discussion and questionnaire; In-depth interview was used with 10 key informants. The researcher investigated the role of cooperatives in attaining sustainable livelihood of members with in-depth interview of 5 cooperative members. The population of the study had comprised 300 war veterans living with disability and are being found engaged in 20 different cooperative unites and therefore the whole population, which is 100% of the participants were target population of the study. The result of the study indicates that cooperatives brought both directly and indirectly a significant physical, psycho-social, and economic rehabilitation among the veteran by unlocking their potential. The compatibility of the cooperative units, the credit facility and infrastructure are found to be the major hindrances to the improvement of productivity of the veterans in cooperatives. More importantly cooperatives; helped the veterans to know more about themselves, that they are productive and have got the potential. The result of the study is presented in a simple table, cross tabulation and bar graph which indicates that cooperatives are the best means ever to unlock the potential of the disabled war veterans and lead them to productivity and independent living economically. Generally it is concluded that cooperatives offered a unique experience for the disabled war veterans to enhance their efforts at empowerment and to decrease their dependence on the state and on their association

Is fine needle aspiration cytology a useful tool for the diagnosis of tuberculous lymphadenitis

Objective: To study the role of fine needle aspiration cytology (FNAC) in the diagnosis of tuberculous lymphadenitis and find a place for FNAC as laboratory diagnostic method in tuberculosis (TB) control programmes. Design: Prospective laboratory study. Method: Duplicate smears from 127 lymphnode aspiration were prepared. Both slides were air-dried. Giemsa stain for cytological examination and Ziehl-Neelsen stain for demonstration of acid fast bacillus(AFB) were used and examined by a pathologist and laboratory technologist respectively. Setting: Tigrai Regional Health Research and Laboratory Centre which is the only unit with microbiological and cytopathological service in the region. Subjects: Patients with one or more enlarged lymph nodes who were sent for FNAC were included. Results: The AFB positivity among the cytologically diagnosed cases of TB lymphadenitis was 56.77%. If we had used culture media for Mycobacterium spp, the positivity would have probably been higher. The positivity rate varied depending on the type of the aspirate. Caseous aspirate showed a higher positivity rate of 60.47% whereas no AFBs were detected in haemorrhagic aspirates. Conclusion: This study has demonstrated the usefulness of FNAC in the diagnosis of TB lymphadenitis and the national TB and leprosy control programmes should encompass FNAC as a diagnostic means instead of biopsy which is more invasive and costly.East African Medical Journal, May 1999, 260-26

Soil erosion modeling and soil quality evaluation for catchment management strategies in northern Ethiopia

About 85% of the Ethiopian population is engaged primarily in agriculture. However, changing environmental factors have led to soil quality (SQ) degradation that poses a critical risk for food security. But, despite some alarming figures, there is no consistent information on the rate and extent of soil degradation in the country. This is due to the fact that the results of research on SQ degradation are more generalized to the country with its different environments and also based on empirical models or on runoff plot studies. It is problematic to extrapolate results from such case studies to other areas, and the resulting reports are thus inadequate to guide policy action on a large scale. Appropriate approaches that address such research gaps are thus needed for the country. This study employs a participatory survey and scientific soil measurements, geostatistics and erosion modeling to concurrently evaluate SQ degradation that can facilitate development of appropriate management strategies for the Mai-Negus catchment conditions in the northern Ethiopian highlands. A participatory SQ survey and group discussions with local farmers were conducted to identify SQ diagnosis indicators as well as the severity and determinants of SQ degradation. Soil samples were collected for analysis from the different SQ categories, land-use and soil management systems and erosion-status sites identified in the catchment. Data were subjected to statistical analysis. A soil erosion model (Soil and Water Assessment Tool; SWAT) interfaced in a GIS environment was evaluated and then applied to identify and prioritize erosion-hotspot sub-catchments. Finally, potential management strategies (scenarios) were simulated targeting prioritized areas to identify scenarios that can better reduce soil degradation caused by erosion. The results of this study show that farmers used indicators such as crop yield, soil depth, soil color, soil erosion risk, sedimentation, for categorizing the catchment soils into high, medium and low SQ status (categories). The scientifically measured soil attributes were significantly different (P ≤ 0.05) among these SQ categories. Using the soil attributes (cation exchange capacity, porosity, sand, total phosphorus, and Ca:Mg) retained in four component factors that explain about 88% of the SQ variability, discriminant analysis correctly classified the soils in the different SQ categories. Such SQ variability shows that farmer evaluation of SQ agrees well with the measured soil attributes. The maps of the interpolated soil properties show a well-defined trend of higher contents of fine soil particles and soil nutrients in the toe-slope and foot-slope areas in the catchment and those with better vegetation cover and soil management practices. The results of the soil erosion model show that > 45% of the catchment area has experienced soil losses through erosion of over 30 t ha-1 y-1, which is higher than the soil loss tolerance for Ethiopia (18 t ha-1 y-1). About 91% of the catchment experienced a soil erosion rate over 15 t ha-1 y-1, which is higher than the average African soil loss (10 t ha-1 y-1). Land management scenarios that involve land-use redesign, terracing, grassed waterways and gully stabilization structures can reduce runoff, sediment yield and nutrient losses by up to 75% at catchment level and up to 90% in the hotspot sub-catchments (soil loss over 18 t ha-1 y-1) as compared to the baseline scenario. Generally, the results of this study confirm that the use of farmers` knowledge to evaluate SQ status and prioritize areas for implementing management intervention is useful as it is rapid, less expensive, has high reproducibility and is reasonably accurate as compared to scientific soil measurements and erosion modeling. This can thus support informed decision-making about SQ degradation in areas where professional experts and resources are limited, and where extrapolation of measured soil data is difficult. However, further research on catchments with contrasting environment is necessary to account for the heterogeneity of farmer knowledge of SQ degradation on a regional and national scale.Modellierung von Bodenerosion und Bewertung von Bodenqualität für Managementstrategien in Nord-Äthiopien Etwa 85% der äthiopischen Bevölkerung ist primär in der Landwirtschaft beschäftigt. Veränderte Umweltfaktoren haben jedoch zu einer Verschechterung der Bodenqualität (soil quality; SQ) geführt, die große Risiken für die Nahrungssicherheit darstellt. Aber trotz alarmierenden Zahlen gibt es kaum konsistente Information über Geschwindigkeit und Ausmaß der Bodendegradation im Lande. Dies liegt daran, dass die Forschungsergebnisse für das gesamte Land mit seinen verschiedenen Umweltbereichen generalisiert werden und auf empirischen Modellen oder Studien über Abflussflächen basieren. Es ist problematisch, die Ergebnisse solcher Fallstudien auf andere Gebiete zu übertragen; die Berichte sind daher als Grundlage für entsprechende Maßnahmen im großen Maßstab ungeeignet. Geeignete Ansätze, die solche Forschungslücken schließen könnten, sind daher notwendig. In dieser Studie wurden partizipative Erhebung, wissenschaftliche Bodenuntersuchungen, Geostatistik, und Erosionsmodellierung eingesetzt, um die SQDegradation zu bewerten und damit die Entwicklung sinnvoller Managementstrategien für die Bedingungen im Mai-Negus Wassereinzugsgebiet im nördlichen Hochland Äthiopiens zu erleichtern. Eine partizipative SQ-Erhebung und Gruppendiskussionen mit örtlichen Farmern wurden durchgeführt, um Indikatoren für eine SQ-Diagnose sowie Ausmaß und Bestimmungsgrößen der SQ-Degradation zu bestimmen. Im Einzugsgebiet wurden zur Analyse Bodenproben aus den verschiedenen SQ-Kategorien, Landnutzung- bzw. Bodenbewirtschaftungssysteme und Bereichen mit unterschiedlichem Erosionsstatus genommen. Die Daten wurden einer statistischen Analyse unterzogen. Ein Boden- Erosionsmodell (Boden und Wasser Bewertungsinstrument; SWAT) innerhalb einer GISUmgebung wurde bewertet und anschließend eingesetzt, um die besonders stark von Erosion betroffenen Bereiche (hotspots) zu ermitteln und priorisieren. Schließlich wurden potentielle Managementstrategien (Szenarien) zielgerichtet auf die priorisierten Bereiche simuliert, um Szenarien zu ermitteln, die am besten erosionsbedingte Bodendegradation reduzieren können. Die Ergebnisse dieser Studie zeigen, dass die Farmer Ertrag, Bodentiefe, Bodenfarbe, Erosionsrisiko und Bodenablagerungen als Indikatoren verwendeten, um die Böden in die Kategorien hohe, mittlere bzw. niedrige SQ einzuteilen. Die wissenschaftlich gemessenen Bodenattribute waren signifikant unterschiedlich (P ≤ 0.05) zwischen diesen SQ-Kategorien. Die Bodenattribute (Kationenaustauschkapazität, Durchlässigkeit, Sandgehalt, Gesamtphosphor und Ca:Mg), die in vier Komponentenfaktoren verblieben, die circa 88% der SQ-Variabilität erklärten, wurden in der Diskriminanzanalyse verwendet und klassifizierten die Böden korrekt in die verschiedenen SQ-Kategorien. Eine solche SQ-Variabilität zeigt, dass die SQ-Bewertung der Farmer mit den gemessenen Bodenattributen gut übereinstimmt. Die Bodenkarten weisen einen klaren Trend mit feinkörnigeren Böden in den Hangfußbereichen sowie in den Bereichen mit höheren Vegetationsbedeckungsgraden und mit besseren Bewirtschaftungsmethoden auf. Die Ergebnisse des Erosionsmodels zeigen, dass > 45% des Gebiets erosionsbedingte Bodenverluste von über 30 t ha-1 y-1 erfahren hat, ein Wert höher als die Bodenverlusttoleranz für Äthiopien (18 t ha-1 y-1). Ungefähr 91% des Gebietes leidet unter Bodenverlusten von über 15 t ha-1 y-1, höher als der afrikanische Durchschnitt von 10 t ha-1 y-1. Managementszenarien mit einer Neuausrichtung der Landnutzung sowie Terrassen, mit Gras bewachsenen Wasserwege sowie Strukturen zur Stabilisierung von Erosionsrinnen können Abfluss, Bodenablagerungen und Nährstoffverluste um bis zu 75% im gesamte Einzugsgebiet verringern und bis zu 90% in den hotspot Bereichen (Bodenverlusts über 18 t ha-1 y-1) verglichen mit dem Grundszenario. Die Ergebnisse dieser Studie bestätigen, dass der Einsatz von Farmerwissen zur Bewertung der SQ und zur priorisieren von Bereichen für die Implementierung von Managementmaßnahmen von großem Nutzen sein kann, da die Methode schnell, weniger teuer, leicht reproduzierbar und verhältnismäßig genau ist verglichen mit Bodenanalysen und Erosionsmodellierung. Diese Methode kann daher Entscheidungen in Bezug auf SQ-Degradation in Gebieten unterstützen wo Experten und Ressourcen beschränkt sind und wo die Extrapolation von Bodendaten schwierig ist. Weitere Untersuchungen über Wassereinzugsgebiete mit unterschiedlichen Umweltbedingungen sind auf regionaler und nationaler Ebene notwendig, um die Heterogenität des Farmerwissens über SQ-Degradation zu berücksichtigen

Performance Measurement of Manufacturing industries in Ethiopia- An Analytical Study

Manufacturing sector is the heart and soul of many developed and developing country’s economy. However, the growth and contribution of the sector to the Ethiopian Economy is at its infant stage. In this study, using time series data base of the central statistics Agency (CSA), the trend in the performance of the manufacturing sector is investigated taking labor productivity as a dependent performance indicator variable. The study covers 15 manufacturing industrial groups as categorized by the CSA. Based on performance reports and related literature reviews, factors that can affect the performance were identified and their influence was analyzed using fixed effects regression model. The result of the analysis indicated that there is overall improvement in the value added growth performance of machinery and equipment, food and beverages, footwear, luggage and handbags manufacturing categories. However, despite the textile and leather industries of Ethiopia have resource based competitive advantage, their performance growth rate is not promising. The human capital, capital intensity, and the firm size (economies of scale) were found as major determinants of the performance of the sector. The average labor productivity of the sector showed incremental growth because of improvements in the educational and skill level of labor forces which has resulted from the intensive government efforts in addressing technical and vocational educations to all citizens. In Ethiopia, there is huge demand for products of manufacturing sectors, hence industries which are producing at large scale using their maximum capacities have shown improvement in their labor productivity. Keywords: value added, labor productivity, performance, manufacturin

Soil Quality Assessment Strategies for Evaluating Soil Degradation in Northern Ethiopia

Soil quality (SQ) degradation continues to challenge sustainable development throughout the world. One reason is that degradation indicators such as soil quality index (SQI) are neither well documented nor used to evaluate current land use and soil management systems (LUSMS). The objective was to assess and identify an effective SQ indicator dataset from among 25 soil measurements, appropriate scoring functions for each indicator and an efficient SQ indexing method to evaluate soil degradation across the LUSMS in the Mai-Negus catchment of northern Ethiopia. Eight LUSMS selected for soil sampling and analysis included (i) natural forest (LS1), (ii) plantation of protected area, (iii) grazed land, (iv) teff (Eragrostis tef)-faba bean (Vicia faba) rotation, (v) teff-wheat (Triticum vulgare)/barley (Hordeum vulgare) rotation, (vi) teff monocropping, (vii) maize (Zea mays) monocropping, and (viii) uncultivated marginal land (LS8). Four principal components explained almost 88% of the variability among the LUSMS. LS1 had the highest mean SQI (0.931) using the scoring functions and principal component analysis (PCA) dataset selection, while the lowest SQI (0.458) was measured for LS8. Mean SQI values for LS1 and LS8 using expert opinion dataset selection method were 0.874 and 0.406, respectively. Finally, a sensitivity analysis (S) used to compare PCA and expert opinion dataset selection procedures for various scoring functions ranged from 1.70 for unscreened-SQI to 2.63 for PCA-SQI. Therefore, this study concludes that a PCA-based SQI would be the best way to distinguish among LUSMS since it appears more sensitive to disturbances and management practices and could thus help prevent further SQ degradation

Trawl-door Shape Optimization by Space-mapping-corrected CFD Models and Kriging Surrogates

AbstractTrawl-doors are a large part of the fluid flow resistance of trawlers fishing gear and has considerable effect on the fuel consumption. A key factor in reducing that consumption is by implementing computational models in the design process. This study presents a robust two dimensional computational fluid dynamics models that is able to capture the nonlinear flow past multi-element hydrofoils. Efficient optimization algorithms are applied to the design of trawl-doors using problem formulation that captures true characteristics of the design space where lift-to-drag ratio is maximized. Four design variables are used in the optimization process to control the fluid flow angle of attack, as well as position and orientation of a leading-edge slat. The optimization process involves both multi-point space mapping, and mixed modeling techniques that utilize space mapping to create a physics-based surrogate model. The results demonstrate that lift-to-drag maximization is more appropriate than lift-constraint drag minimization in this case and that local search using multi-point space mapping can yield satisfactory design at low computational cost. By using global search with mixed modeling a solution with higher quality is obtained, but at a higher computational cost than local search

Predicting soil erosion after land use changes for irrigating agriculture in a large reservoir of southern Portugal

The construction of the Alqueva reservoir in a semi-arid Mediterranean landscape brought new opportunities for irrigated farming. Land use changes and climate change may alter the risk of soil erosion that was not predicted in the initial development plans and decrease the lifetime of the investment. A comprehensive methodology that integrates the Revised Universal Soil Loss Equation (RUSLE) and geographic information system was adopted to study the effect on soil erosion of different land-uses of the Alqueva reservoir region. Analysing the soil erosion of each land-use it was obtained the following land use erosion vulnerability: Olive orchard>Vineyard>Montado>Alfalfa. The strong erosion variances that were observed in the study area show the importance of locating the 'hot spots' of soil erosion. Simulated scenarios for the entire area can be used as a basis for site-specific soil conservation plans, to promote sustainable land management practices and to facilitate localized erosion control practices and environmentally friendly farming. (C) 2015 The Authors. Published by Elsevier B.V

PV with multiple storage as function of geolocation

© 2018 Elsevier Ltd A real PV array combined with two storage solutions (B, battery, and H, hydrogen reservoir with electrolyzer-fuel cells) is modeled in two geolocations: Oxford, UK, and San Diego, California. All systems meet the same 1-year, real domestic demand. Systems are first configured as standalone (SA) and then as Grid-connected (GC), receiving 50% of the yearly-integrated demand. H and PV are dynamically sized as function of geolocation, battery size B M and H's round-trip efficiency η H . For a reference system with battery capacity B M =10 kW h and η H =0.4, the required H capacity in the SA case is ∼1230 kW h in Oxford and ∼750 kW h in San Diego (respectively, ∼830 kW h and ∼600 kW h in the GC case). Related array sizes are 93% and 51% of the reference 8 kW p system (51% and 28% for GC systems). A trade-off between PV size and battery capacity exists: the former grows significantly as the latter shrinks below 10 kW h, while is insensitive for B M rising above it. Such a capacity achieves timescales’ separation: B, costly and efficient, is mainly used for frequent transactions (daily periodicity or less); cheap, inefficient H for seasonal storage instead. With current PV and B costs, the SA reference system in San Diego can stay within 2·10 4 $CapEx if H's cost does not exceed ∼7$/kW h; this figure increases to 15 $/kWh with Grid constantly/randomly supplying a half of yearly energy (6.5$/kWh in Oxford, where no SA system is found below 2·10 4 $ CapEx). Rescaling San Diego's array (further from its optimal configuration than Oxford's) to the ratio between local, global horizontal irradiance (GHI) and Oxford GHI, yields in all cases a 11% reduction of size and corresponding cost, with the other model outputs unaffected. The location dependent results vary to different extents when extending the modeled timeframe to 18 years. In any case, the variability stays within ±10% of the reference year