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Phenotypic diversity in Ethiopian durum wheat(Triticum turgidum ***)landraces

The Crop Journal 2015年第3期3卷 190-199页

作者： Dejene K.Mengistu afeworki y.kiros Mario E.Pè Department of Dryland Crop and Horticultural Sciences Mekelle University P.O.Box 231 Mekelle Ethiopia Scuola Superiore Sant'Anna (SSSUP) Pizza Martiri Liberà 33 – 56127 Pisa Italy

The phenotypic diversity of 274 Ethiopian durum wheat accessions was analyzed, taking their geographic origins into account. The aim was to assess the extent and patterns of agronomically important phenotypic variation across districts of origin and altitude classes for major qualitative traits using diversity index and multivariate methods. Eight qualitative and three quantitative traits were scored for 2740 plants and analyzed for diversity. The Shannon–Weaver diversity(H′) index was used to estimate phenotypic diversity. The estimated H′ ranged from monomorphic for glume hairiness to highly polymorphic for other traits. The highest(0.86) H′ was obtained for seed degree of shriveling, possibly indicating the differential responses of the genotypes to water deficit during later growth stages. With respect to district of origin, the highest(0.72) and lowest(0.44) H′ values were obtained for the Bale and SNNP districts, respectively. With respect to altitude, the highest(0.76) and lowest(0.62) H′ values were recorded for altitudes 1600–2000and > 3000 m above sea levels, respectively. Principal components analysis explained substantial variation contributed by district of origin and altitude range. Genotypes were clustered into three groups by districts of origin and altitude class, with relatively strong bootstrap values of 57 and 62 for the former and latter, respectively. It could be concluded that Ethiopian durum wheat landraces are very diverse both within and among districts of origin and altitude classes. This wealth of genetic diversity should be exploited for wheat improvement of yield and for resistance to biotic and abiotic stresses, particularly terminal drought.

关键词： Phenotypic diversity Diversity index Landraces Districts of origin Altitude Ethiopia

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Experimental evaluation of rice husk ash for applications in geopolymer mortars

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Journal of Bioresources and Bioproducts 2021年第2期6卷 160-167页

作者： G.Ogwang P.W.Olupot H.Kasedde E.Menya H.Storz y.kiros Department of Mechanical Engineering College of EngineeringDesignArt and TechnologyMakerere UniversityP.O.Box 7062Kampala-Uganda Department of Biosystems Engineering Gulu UniversityP.O.Box 166GuluUganda Thuenen Institute of Agricultural Technology Bundesallee 4738116 BraunschweigGermany Department of Chemical Engineering KTH Royal Institute of TechnologySE 10044 StockholmSweden

Rice husks obtained from upland and lowland rice varieties were characterized for composition and content of *** of the rice husk varieties was fired at temperatures of 600,800 and 900℃ for a soaking period of 3 *** resultant rice husk ash was analyzed for oxide composition and crystallinity using X-ray fluorescence and diffraction techniques,*** generated amorphous ash with the highest silica content,together with metakaolin,aggregate,water,and an alkaline activator was employed to formulate geo-polymer mortar prisms according to the standard EN *** showed that the content of ash in the varieties ranged from 18.3%to 28.6%dry *** of this,89 wt%-96 wt%was silica,with amorphous and crystalline forms of silica obtained at 600℃ and 900℃,respectively,regardless of the rice ***,at 800℃,the silica in the generated ash exhibited both amorphous and crystalline *** amorphous ash generated at 600℃ was used in formulation of geopolymer *** and flexural strength of the formulated mortar after 7 days of curing was 1.5 and 1.3 MPa,*** results reveal the firing protocol to form pozzolanic ash,with potential applications in mortar production.

关键词： Rice husk ash Metakaolin Activator Geopolymer mortar Characterization

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Arbuscular mycorrhizal fungi improve biomass, photosynthesis, and water use efficiency of Opuntia ficus-indica (L.) Miller under different water levels

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Journal of Arid Land 2023年第8期15卷 975-988页

作者： Teame G KEBEDE Emiru BIRHANE kiros-Meles AyIMUT yemane G EGZIABHER Department of Land Resource Management and Environmental Protection College of Dryland Agriculture and Natural ResourceMekelle UniversityMekelle 231Ethiopia Department of Animal Production and Technology College of Agriculture and Environmental ScienceAdigrat UniversityAdigrat 50Ethiopia Institute of Climate and Society Mekelle UniversityMekelle 231Ethiopia Department of Dryland Crop and Horticultural Science College of Dryland Agriculture and Natural ResourceMekelle UniversityMekelle 231Ethiopia

Opuntia ficus-indica(L.)Miller is a CAM(crassulacean acid metabolism)plant with an extraordinary capacity to adapt to drought stress by its ability to fix atmospheric CO_(2) at nighttime,store a significant amount of water in cladodes,and reduce root *** that grow in moisture-stress conditions with thick and less fine root hairs have a strong symbiosis with arbuscular mycorrhizal fungi(AMF)to adapt to drought *** stress can limit plant growth and biomass production,which can be rehabilitated by AMF association through improved physiological *** objective of this study was to investigate the effects of AMF inoculations and variable soil water levels on the biomass,photosynthesis,and water use efficiency of the spiny and spineless *** experiment was conducted in a greenhouse with a full factorial experiment using ***-indica type(spiny or spineless),AMF(presence or absence),and four soil water available(SWA)treatments through seven *** treatments applied were 0%–25%SWA(T1),25%–50%SWA(T2),50%–75%SWA(T3),and 75%–100%SWA(T4).Drought stress reduced biomass and cladode growth,while AMF colonization significantly increased the biomass production with significant changes in the physiological performance of *** presence significantly increased biomass of both ***-indica plant types through improved growth,photosynthetic water use efficiency,and *** presence of spines on the surface of cladodes significantly reduced the rate of photosynthesis and photosynthetic water use *** photosynthesis,photosynthetic water use efficiency,transpiration,and stomatal conductance rate significantly decreased with increased drought *** drought stress,some planted mother cladodes with the absence of AMF have not established daughter cladodes,whereas AMF-inoculated mother cladodes fully established daughter *** root colonization significantly increased with the decrease o

关键词： biomass cactus pear cladode growth photosynthesis water stress water use efficiency

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Impact analysis of compressor rotor blades of an aircraft engine

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Frontiers of Structural and Civil Engineering 2019年第3期13卷 505-514页

作者： y B SUDHIR SASTRy B G kiros F HAILU R BUDARAPU Department of Aeronautical Engineering Institute of Aeronautical EngineeringDundigalHyderabad 500043India Department of Aeronautical Engineering College of EngineeringDefense UniversityBishoftu 1041Ethiopia School of Mechanical Sciences Indian Institute of Technology BhubaneswarBhubaneswar 752050India

Frequent failures due to foreign particle impacts are observed in compressor blades of the interceptor fighter MIG-23 aircraft engines in the Ethiopian air force,supplied by the Dejen Aviation *** this paper,we made an attempt to identify the causes of failure and hence recommend the suitable materials to withstand the foreign particle *** and stress analysis of one of the recently failed MIG-23 gas turbine compressor blades made up of the following Aluminum based alloys:6061-T6,7075-T6,and 2024-T4,has been performed,apart from the impact analysis of the rotor blades hit by a granite *** numerical results are correlated to the practical *** on the modal,stress and impact analysis and the material properties of the three considered alloys,alloy 7075-T6 has been recommended as the blade material.

关键词： axial flow compressor rotor and stator blades aircraft engine stress and impact analysis aluminum alloys

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Spatially explicit statistical modeling of random and systematic land cover transitions in the main grassland plain of Nech Sar National Park, Ethiopia

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Ecological Processes 2019年第1期8卷 560-579页

作者： kiros Tsegay Deribew Department of Geography and Environmental Studies Jimma UniversityP.O.Box 378JimmaEthiopia

The main grassland plain of Nech Sar National Park(NSNP)is a federally managed protected area in Ethiopia designated to protect endemic and endangered ***,like other national parks in Ethiopia,the park has experienced significant land cover change over the past few ***,the livelihoods of local populations in such developing countries are entirely dependent upon natural resources and,as a result,both direct and indirect anthropogenic pressures have been placed on natural *** previous research has looked at land cover change in the region,these studies have not been spatially explicit and,as a result,knowledge gaps in identifying systematic transitions continue to *** study seeks to quantify the spatial extent and land cover change trends in NSNP,identify the strong signal transitions,and identify and quantify the location of determinants of *** this end,the author classifies panchromatic aerial photographs in 1986,multispectral SPOT imagery in 2005,and Sentinel imagery in *** spatial extent and trends of land cover change analysis between these time periods were *** strong signal transitions were systematically identified and ***,the basic driving forces of the change were *** locations of these transitions were also identified and quantified using the spatially explicit statistical *** analysis revealed that over the past three decades(1986–2019),nearly 52%of the study area experienced clear landscape change,out of which the net change and swap change attributed to 39%and 13%,*** conversion of woody vegetation to grassland(~5%),subsequently grassland-to-open-overgrazed land(28.26%),and restoration of woody vegetation(0.76%)and grassland(0.72%)from riverine forest and open-overgrazed land,respectively,were found to be the fully systematic transitions whereas the rest transitions were recorded either partly systematic or random *** location of these most sy

关键词： Agro-pastoralist Deforestation Degradation Overgrazing Pastoralists

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Spatiotemporal analysis of urban growth on forest and agricultural land using geospatial techniques and Shannon entropy method in the satellite town of Ethiopia,the western fringe of Addis Ababa city

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Ecological Processes 2020年第1期9卷 526-541页

作者： kiros Tsegay Deribew Department of Geography and Environmental Studies Jimma UniversityP.O.Box 378JimmaEthiopia

Rapid conversion of conserved land and cropland to non-agricultural purposes is threatening the ecological areas and dominant agricultural activities that are the main sources of livelihood in urban fringe areas of Addis Ababa *** combinations of government policy,socioeconomic,demographic dynamics,and biophysical triggers have driven such ***,the recent fast urban expansion and infrastructural development could have accelerated the severity and rate at which urban growth impacts the ecosystem and fertile agricultural ***,little attention is given about their impacts on forest and farming communities in the western fringe areas of Addis Ababa during the recent *** study,therefore,aimed at quantifying and analyzing the trends of the urban growth and its impacts on flora and agricultural land in Sebeta-Awas town using an integrated GIS tool,remote sensing technique,and Shannon entropy *** TM of 1986,ETM+of 2002,and OLI of 2019 were used to produce land use/land cover(LULC)***-based classification technique was carried out to generate the LULC and to measure the changes in the urban land-use class within the satellite town in the year 1986,2002,and *** entropy method was applied to model study area’s urban sprawl,growth trend,and spatial *** the past three decades(1986-2019),Sebeta-Awas town has experienced severe urban sprawl following lack of proper development control and *** annual urban growth rates of 1.2,5.5,and~15%for the periods of 1986,2002,and 2019,respectively were obtained mainly at the expenses of agricultural land(25.48%)and forest land(16.6%),catalyzed urban sprawl which finally led to serious deforestation and reduction in rural *** findings indicate that the average of entropy index increased from 0.02 in the year 1986 to 0.996 in the year 2019,indicating more dispersed urban growth to the outskirts,and spatially indicating anticlockwise *** this rega

关键词： Concentric rings Entropy index Urbanization Urban sprawl

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Effect of endogenous hydrogen utilization on improved methane production in an integrated microbial electrolysis cell and anaerobic digestion： Employing catalyzed stainless steel mesh cathode

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Chinese Journal of Chemical Engineering 2018年第3期26卷 574-582页

作者： kiros Hagos Chang Liu Xiaohua Lu State Key Laboratory of Materials-Oriented Chemical Engineering Nanjing Tech University Nanjing 210009 China Mizan-Tepi University Mizan-Aman 260 Ethiopia

Improving the production of methane, while maintaining a significant level of process stability, is the main challenge in the anaerobic digestion process. Recently, microbial electrolysis cell(MEC) has become a promising method for CO_2 reduction produced during anaerobic digestion(AD) and leads to minimize the cost of biogas upgrading technology. In this study, the MEC-AD coupled reactor was used to generate and utilize the endogenous hydrogen by employing biocompatible electrodeposited cobalt-phosphate as catalysts to improve the performance of stainless steel mesh and carbon cloth electrodes. In addition, the modified version of ADM1 model(ADM1 da) was used to simulate the process. The result indicated that the MEC-AD coupled reactor can improve the CH_4 yield and production rate significantly. The CH_4 yield was enhanced with an average of 48% higher than the control. The CH_4 production rate was also increased 1.65 times due to the utilization of endogenous *** specific yield, flow rate, content of CH_4, and p H value were the variables that the model was best at predicting(with indexes of agreement: 0.960/0.941, 0.682/0.696, 0.881/0.865, and 0.764/0.743) of the process with SSmeshes 80/SS-meshes 200, respectively. Employing the catalyzed SS mesh cathode, in the MEC-AD coupled reactor, could be an effective approach to generate and facilitate the utilization of endogenous hydrogen in anaerobic digestion of CH_4 production technology, which is a promising and feasible method to scale up to the industrial level.

关键词：消化过程生产率催化剂不锈钢微生物厌氧网孔阴极

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Current and future predicting potential areas of Oxytenanthera abyssinica(***)using MaxEnt model under climate change in Northern Ethiopia

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Ecological Processes 2020年第1期9卷 59-73页

作者： yikunoamlak Gebrewahid Selemawi Abrehe Esayas Meresa Gebru Eyasu kiros Abay Gebrehiwot Gebreab kiros Kidanemariam Gezu Adissu Gebrekidan Abreha Girmay Darcha Mekelle Agricultural Research Center(MARC) Tigray Agricultural Research Institute(TARI)P.O.Box 256TigrayEthiopia Mekelle Soil Research Center(MSRC) Tigray Agricultural Research Institute(TARI)P.O.Box 1070TigrayEthiopia Humera Agricultural Research Center(HuARC) Tigray Agricultural Research Institute(TARI)P.O.Box 62TigrayEthiopia Abergele Agricultural Research Center(AARC) Tigray Agricultural Research Institute(TARI)P.O.Box 44TigrayEthiopia Shire-Mytsebri Agricultural Research Center(SmARC) Tigray Agricultural Research Institute(TARI)P.O.Box 241TigrayEthiopia

Introduction:Climate change will either improve,reduce,or shift its appropriate climatic habitat of a particular species,which could result in shifts from its geographical *** the potential distribution through MaxEnt modeling has been developed as an appropriate tool for assessing habitat distribution and resource conservation to protect bamboo ***:Our objective is to model the current and future distribution of Oxytenanthera abyssinica(***)based on three representative concentration pathways(RCP)(RCP2.6,RCP4.5,and RCP8.5)for 2050s and 2070s using a maximum entropy model(MaxEnt)in Northern *** modeling procedure,77 occurrence records and 11 variables were retained to simulate the current and future distributions of Oxytenanthera abyssinica in Northern *** evaluate the performance of the model,the area under the receiver operating characteristic(ROC)curve(AUC)was ***:All of the AUCs(area under curves)were greater than 0.900,thereby placing these models in the“excellent”*** jackknife test also showed that precipitation of the coldest quarter(Bio19)and precipitation of the warmest quarter(Bio18)contributed 66.8%and 54.7%to the *** the area of current distribution,1367.51 km2(2.52%),7226.28 km2(13.29%),and 5377.26 km2(9.89%)of the study area were recognized as high,good,and moderate potential habitats of Oxytenanthera abyssinica in Northern Ethiopia,and the high potential area was mainly concentrated in Tanqua Abergele(0.70%),Kola Temben(0.65%),Tselemti(0.60%),and Tsegede(0.31%).Kafta Humera was also the largest good potential area,which accounts for 2.75%.Compared to the current distribution,the total area of the high potential regions and good potential regions for Oxytenanthera abyssinica under the three RCPs(RCP2.6,RCP4.5,and RCP8.5)would increase in the 2050s and ***,the total area of the least potential regions under the three RCPs(RCP2.6,RCP4.5,and RCP8.5)in 2050s and 2070s would

关键词： Oxytenanthera abyssinica MaxEnt model Climate change

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Evaluation of land suitability for Moringa oleifera tree cultivation by using Geospatial technology:The case of Dhidhessa Catchment,Abay Basin,Ethiopia

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Oil Crop Science 2023年第1期8卷 45-55页

作者： Mitiku Badasa Moisa Muleta Ebissa Feyissa Indale Niguse Dejene Firdissa Sadeta Tiye kiros Tsegay Deribew Zenebe Reta Roba Mengistu Muleta Gurmessa Dessalegn Obsi Gemeda Department of Agricultural Engineering Faculty of TechnologyWollega University Shambu CampusEthiopia Department of Earth Sciences College of Natural and Computational SciencesWollega University Nekemte CampusNekemteEthiopia Department of Geography and Environmental Studies Wollega UniversityGimbi CampusGimbiEthiopia Department of Geography and Environmental Studies Raya UniversityMaichewEthiopia Department of Forestry College of Natural Resource and Agricultural EconomicsMettu University Bedele CampusEthiopia Department of Fisheries and Aquatic Sciences Faculty of AgricultureWollega University Shambu CampusShambuEthiopia Department of Natural Resource Management College of Agriculture and Veterinary MedicineJimma UniversityEthiopia

Land suitability analysis of Moringa oleifera tree cultivation is important to enhance its product,as the demand forthis tree for medicinal values and food sources is increasing ***,this study aimed to assess suitableland for Moringa oleifera tree cultivation by using the integration of multi-criteria evaluation with geospatialtechnologies in the Dhidhessa catchment,western *** parameters,namely:slope,land use and landcover(LULC),soil texture,land surface temperature,and rainfall data,were used in this *** land suitabilityevaluation of Moringa oleifera is classified into three classes as highly suitable,moderately suitable,and *** results revealed that,about 344.4 km2(12.2%)of the area is categorized into highly suitable,and2343.7 km2(83%)is moderately suitable for Moringa tree,whereas,137.2 km2(4.9%)is categorized as notsuitable for Moringa oleifera tree ***,based on the finding of the study,we suggested that farmers andother stakeholders can cultivate Moringa oleifera trees in the Dhidhessa catchment.

关键词： Moringa tree Medicinal plant Overlay analysis AHP MCE

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Carbon stocks and sequestration potential of dry forests under community management in Tigray, Ethiopia

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Ecological Processes 2017年第1期6卷 203-213页

作者： Negasi Solomon Emiru Birhane Tewodros Tadesse Anna C.Treydte kiros Meles Department of Land Resources Management and Environmental Protection Mekelle UniversityP.O.Box 231MekelleEthiopia Faculty of Environment sciences and Natural Resources Management Norwegian University of Life SciencesP.O.Box 5003No-1432ÅsNorway Department of Natural Resources Economics and Management Mekelle UniversityP.O.Box 231MekelleEthiopia Agroecology in the Tropics and Subtropics University of HohenheimStuttgartGermany Nelson Mandela African Institution of Science and Technology ArushaTanzania World Agroforestry Centre(ICRAF) ILRI CampusP.O.Box 5689Addis AbabaEthiopia

Introduction:Forests form a major component of the carbon(C)reserves in the world’s ***,little is known on how management influences C stocks of woody vegetation,particularly in dry *** developed regression models for two dominant tree species to predict C stocks and quantified the potential of community managed forests as C ***:Plots were randomly selected from community-managed natural forest,herbivore exclosures,and from communal grazing *** and shrub biomass were estimated using a regression model on the most dominant woody species while herbaceous biomass was determined using destructive ***:The simplest model,based on only one single predictor variable,showed a good fit to the data for both species(Juniperus procera and Acacia abyssinica).Diameter at breast height(r2>0.95)was a more reliable predictor than height(r2>0.54),crown diameter(r2>0.68)(py,while that for the grazing land was 7.76 Mg ha−1,and the mean carbon content between the three land uses were significantly different(py the community have a high potential for C sequestration and storage and their conservation should be promoted.

关键词： Allometric functions Regression Dryland Livestock pressure Woody and grassy vegetation Exclosures

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