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Ecological Processes 2024年第2期 260-278页

作者： Haile Abebe Anteneh Belayneh Desta sintayehu Workneh Dejene Africa Center of Excellence in Climate Smart Agriculture and Biodiversity Conservation Haramaya University School of Biological Sciences and Biotechnology College of Natural and Computational SciencesHaramaya University

Background Aloe ankoberensis M.G. Gilbert & Sebsebe and A. debrana Christian are Ethiopian endemic species currently classified as endangered and least concern, respectively under International Union for Conservation of Nature(IUCN) categories. Recent studies indicate that climate change is anticipated to significantly influence the distribution of plant species. Therefore, this study aimed to model the distribution of A. ankoberensis and A. debrana under different climate change scenarios in the North Shewa Zone, Amhara National Regional State of Ethiopia. Thirty-six and 397 georeferenced presence points for A. ankoberensis and A. debrana, respectively, and 12 environmental variables were used to simulate their current and future distributions. The ensemble model approach was used to examine the current and future(2050 and 2070) climatic suitability for both species under three shared socio-economic pathway(SSP) climate scenarios(SSP 2.6, 4.5 and 8.5).Results The performance of ensemble model was excellent for A. ankoberensis with score of area under curve(AUC) 0.96 and true skill statistics(TSS) 0.88, and good for A. debrana with score of AUC 0.87 and TSS 0.63. The main variables that affected the species' distributions were mean diurnal range of temperature, annual precipitation, and elevation. According to the model, under the current climate conditions, 98.32%, 1.01%, 0.52%, and 0.15% were not suitable, lowly, moderately, and highly suitable areas, respectively for A. ankoberensis, and 63.89%, 23.35%, 12.54%, and 0.21% were not suitable, lowly, moderately and highly suitable areas, respectively for A. debrana. Under future climate scenarios, suitable habitats of these species could shrink. In addition, under all climate change scenarios, it is anticipated that highly suitable areas for both species and moderately suitable areas for A. ankoberensis will be lost completely in the future unless crucial interventions are done on *** The results indicat

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Role of phase fluctuation and dephasing in the enhancing continuous variable entanglement of a two-photon coherent beat laser

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Chinese Physics B 2012年第1期21卷 210-221页

作者： sintayehu Tesfa Max Planck Institute for the Physics of Complex Systems Nthnitzer Str.3801187 DresdenGermany Physics DepartmentDilla UniversityP.O.Box 419DillaEthiopia

A steady state analysis of the nonclassical features and statistical properties of the cavity radiation of a two- photon coherent beat laser is presented. Results show that the degree of two-mode squeezing, detectable entanglement and intensity of the cavity radiation can increase with the deviation of the phase fluctuations of the laser employed in preparing the atoms, but decrease with the increasing rate at which the induced coherence superposition decays. Although it is found that varying the phase fluctuations and dephasing can lead to modification in the quantum features and statistical properties of the radiation, it does not alter the similarity in the nature of the degree of entanglement detectable by the criteria following from Duan-Giedke-Cirac Zoller and logarithmic negativity in a perceivable manner. Since the intensity and quantum features can be readily enhanced, this system is expected to be a viable source of a strong robust entangled （squeezed） light under various conditions. Moreover, comparison of the mean number of photon pairs with intensity difference shows that the chance of inciting a two-photon process can be enhanced by changing the rate of dephasing and phase fluctuations.

关键词： coherent beat laser phase fluctuations dephasing entanglement

Impact of climate change on biodiversity and associated key ecosystem services in Africa:a systematic review

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Ecosystem Health and Sustainability 2018年第9期4卷 1-16页

作者： Dejene W.sintayehu College of Agriculture and Environmental Sciences Haramaya UniversityDire DawaEthiopia

Introduction:Biodiversity and biodiversity-based ecosystems services are intrinsically dependent on the *** the twentieth century,climate change has posed major threats to biodiversity in Africa,and impacts are expected to increase as climate change continues and perhaps even ***:Our review shows that the multiple components of climate change are projected to affect all levels of biodiversity,from genes over species to biome *** of biodiversity as a result of climate change can alter the structures and functions of African ecological *** a result,the provision of biodiversity-based ecosystem services and the wellbeing of people that rely on these services are being *** particular concerns are“tipping points”where the exceedance of ecosystem thresholds will possibly lead to irreversible shifts of the structure of ecosystems and their *** recent years,climate prediction models have portended continued warming and more frequent extreme weather events across the *** weather-related disturbances such as El Niño will place a premium on biodiversity and biodiversity-based ecosystem services that people rely ***:As biodiversity underlies all goods and services provided by ecosystems that are crucial for human survival and well-being,this paper synthesizes and discusses observed and anticipated impacts of climate change on biodiversity and biodiversity-based ecosystem service provision and livelihoods,and what strategies might be employed to decrease current and future risks on the well-being of human in Africa.

关键词： Agricultural production climate regulation disease regulation provisioning services regulating services tipping points

Predicting invasion potential of Senna didymobotrya (Fresen.) Irwin & Barneby under the changing climate in Africa

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Ecological Processes 2021年第1期10卷 89-98页

作者： Elias Ch.Weldemariam Dejene sintayehu W. Department of Geo-information Science Haramaya UniversityDire DawaEthiopia College of Agriculture and Environmental Sciences Haramaya UniversityDire DawaEthiopia

Background:Senna didymobotrya is a native African flowering *** is suspected that climate change encourages the introduction and spread of invasive alien *** possible invasion of *** across the continent is expected to increase in the future due to ongoing climate ***,there is still paucity of empirical evidence on the extent to which the changing climate contributes to the surge of the flowering *** study,therefore,investigated the present and potential invasion of *** using the species distribution model under changing climate *** two representative concentration pathways(RCP4.5 and RCP8.5)and eight bioclimatic variables and one topographic variable were used to simulate the current and future(2050s and 2070s)invasion of *** in *** model performance was assessed using the area under the receiver operating characteristic curve(AUC)and true skill statistics(TSS).Results:The results of the study showed that under the current climatic conditions,18%of Africa is suitable for the establishment and invasion of *** most suitable hotspot for *** invasion is eastern Africa,followed by southern *** predicted model showed that by 2050,3.3%and 3.12%of the continent would be highly suitable areas for the invasion of the species under RCP4.5 and RCP8.5,*** the 2070s,under RCP4.5 and RCP8.5,the highly suitable area would be 3.13%and 2.7%,*** relation to the current suitability,the cumulative projected areas of the low and moderate suitability class under RCP4.5 and RCP8.5 will rise by the years 2050 and ***,under both RCPs,the non-suitable area for *** invasion would gradually ***:From the findings,it can be concluded that the ecosystem’s vulnerability to *** invasion under future climatic conditions will proliferate ***,to prevent the projected harm to biodiversity and ecosys

关键词： Senna didymobotrya Invasive species Climate change Africa Ensemble approach

Aboveground carbon stock is related to land cover and woody species diversity in tropical ecosystems of Eastern Ethiopia

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Ecological Processes 2020年第1期9卷 423-432页

作者： Dejene W.sintayehu Anteneh Belayneh Nigussie Dechassa College of Agriculture and Environmental Sciences Haramaya UniversityHaramayaEthiopia College of Natural and Computational Sciences Haramaya UniversityHaramayaEthiopia Africa Centre of Excellence for Climate Smart Agriculture and Biodiversity Conservation Haramaya UniversityHaramayaEthiopia

Background:Current theories on biodiversity-carbon sequestration relationship describe biodiversity as an important factor influencing carbon storage,either through complementarity effect or by mass ratio *** far,the expected form of biodiversity-carbon relationships in tropical ecosystems has not been known with ***,we explored the relationship between aboveground carbon stock and different biodiversity measurement indices(i.e.,species richness,species diversity,species evenness,and functional diversity)in different land cover types of Eastern Ethiopia.A total of 48 plots were established using stratified random *** parameters such as diameter at breast height,diameter at stump height,tree height,and species type were ***:We found that the average aboveground carbon stock of the study area is 147.6±17.2 t ha^(−1)(mean,SE)across land cover *** richness,Shannon index,and functional diversity together explained 73.5%,61.4%,58.9%,and 52.0%of the variation in aboveground carbon storage in woodland,riparian forest,bushland,and farmland,*** diversity was a significant predictor explaining the total aboveground carbon stocks(26.7%)across the land cover *** effects of biodiversity on aboveground carbon storage were mediated by functional diversity and presence and dominance of *** shows that both the selection effects and the niche complementarity are important for carbon ***,the impact of functional diversity effects(niche complementarity)was higher than that of functional dominance effects(selection effects).Conclusions:Implementation of protected area-based ecosystem conservation practices in the country seems feasible to mitigate climate change and Reducing Emissions from Deforestation and Forest Degradation(REDD+)programme should emphasize on biodiversity conservation.

关键词： Niche complementarity effect Functional diversity Selection effect Species diversity Species richness

Multi-criteria decision making methods to address rural land allocation problems:A systematic review

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International Soil and Water Conservation Research 2021年第4期9卷 490-501页

作者： sintayehu Legesse Gebre Dirk Cattrysse Esayas Alemayehu Jos Van Orshoven Department of Mechanical Engineering Center for Industrial ManagementTraffic&InfrastructureKU Leuven(University of Leuven)Celestijnenlaan 3003001LeuvenBelgium Department of Earth and Environmental Sciences Division of ForestNature and LandscapeKU Leuven(University of Leuven)Celestijnenlaan 200E3001LeuvenBelgium Department of Natural Resource Management Jimma UniversityJimmaEthiopia Department of Civil and Environmental Engineering JITJimma UniversityJimmaEthiopia

Land allocation has been an important issue in land use planning research *** allocation involves different multifunctional activities of maximizing environmental,economic and social ***-criteria decision making(MCDM)method is the most popular tool to optimize land allocation problems by considering decision variables,conflicting objectives,and ***,decision-makers face problems on how to optimize the land allocation while minimizing the conflicting trade-offs existing in the decision *** this review study,we aim at identifying and extracting information on MCDM methods to solve land allocation problems from English language articles published between 2000 and 2019 and indexed by four scientific literature databases(Web of Science,Science Direct,Scopus,Google scholar).To this end,we applied a systematic literature review approach,*** Preferred Reporting Items for Systematic Reviews and Meta-Analysis procedure(Moher et al.,2009),with a structured database search expression.120 articles were selected of which,after careful screening of title,keywords and abstract,69 were retained for detailed *** review study report compiles comprehensive information by classifying the papers into application area,optimization objectives,criteria used,decision techniques,publication year and study *** summary,we found that in the last two decades,the use of the MCDM method has increased,particularly in Europe and ***(analytical hierarchal process)is frequently used for multi-attribute land allocation problems with reference to ecotourism and ecosystem ***(linear programming)and SA(simulating annealing)methods are predominantly used to optimize multi-objectives complex agricultural and forest land allocation problems respectively.

关键词： Database Allocation Decision techniques PRISMA

Genome-wide association study in historical and contemporary *** wheats identifies heightreducing loci

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The Crop Journal 2020年第2期8卷 243-251页

作者： sintayehu D.Daba Priyanka Tyagi Gina Brown-Guedira Mohsen Mohammadi Department of Agronomy Purdue UniversityWest LafayetteIN 47907USA Department of Crop and Soil Sciences North Carolina State UniversityRaleighNC 27695USA U.S.Department of Agriculture Agricultural Research ServicesSoutheast AreaPlant Science ResearchRaleighNC 27695USA

Plant height has been a major target for selection of high-yielding varieties in *** height-reducing loci(Rht-B1 and Rht-D1)have been widely used since the Green ***,these genes also negatively affect other agronomic traits such as kernel *** alternative height-reducing loci could benefit wheat *** study focused on the genetics of plant height in 260 historical and contemporary winter wheat accessions via genome-wide association studies using 38,693 single nucleotide polymorphism(SNP)markers generated through genotyping by sequencing,two Kompetitive Allele Specific Polymorphismmarkers,and phenotypic data recorded in two seasons(2016 and 2018).The 260 accessions showed wide variation in plant *** accessions developed after 1960 were shorter than earlier *** broad-sense heritability for plant height was high(H2=0.82),whichwas also supported by a high correlation(r=0.82,P<0.0001)between heights from the two *** detected a total of 16 marker–trait associations(MTAs)for plant height at–lg(P)≥4.0 on chromosomes 1A,2B,2D,3B,4D,5A,5D,6A,6B,7A,and *** detected three of the MTAs(QPLH-2D,QPLH-4B.2,and QPLH-4D)consistently in individual-year and combined-year *** MTAs individually explained 10%–16%of phenotypic *** heightreducing alleles at these threeMTAs appeared after 1960 and increased in frequency *** the genes near these loci were gibberellic acid insensitive(GAI)and GRAS transcription factor(GIBBERELLIC-ACID INSENSITIVE(GAI),REPRESSOR of GAI(RGA),and SCARECROW(SCR)).The evidence from this study and previous reports suggests that QPLH-2D is Rht8.A gene encoding a GRAS transcription factor is located near *** of the QPLH-2D locus and associated candidate genes awaits further study.

关键词： GWAS Marker-trait associations Rht-B1 Rht-D1 Candidate genes Position-dependent procedures

Evolution of drought and flood events on the Qinghai-Tibet Plateau and key issues for response

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Science China Earth Sciences 2023年第11期66卷 2514-2529页

作者： Jie LU Shu XU Tianling QIN Xin HE Denghua YAN Cheng ZHANG sintayehu A.ABEBE State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China Yinshanbeilu National Field Research Station of Steppe Eco-hydrological System China Institute of Water Resources and Hydropower ResearchHohhot 010020China Hydraulic and Water Resources Engineering Department Debre Markos University Institute of TechnologyDebre Markos 999047Ethiopia

The Qinghai-Tibet Plateau is a climate-sensitive *** characteristics of drought and flood events in this region are significantly different as compared to other areas in the country,which could potentially induce a series of water security,ecological and environmental *** is urgent that innovative theories and methods for estimation of drought and flood disasters as well as their adaptive regulations are *** on extensive literature review,this paper identifies new situations of the evolution of drought and flood events on the Qinghai-Tibet Plateau,and analyzes the research progress in terms of monitoring and simulation,forecasting and early warning,risk prevention and emergency *** study found that there were problems such as insufficient integration of multi-source data,low accuracy of forecasting and early warning,unclear driving mechanisms of drought and flood disaster chains,and lack of targeted risk prevention and regulation *** this basis,future research priorities are proposed,and the possible research and development paths are elaborated,including the evolution law of drought and flood on the Qinghai-Tibet Plateau,the coincidence characteristics of drought and flood from the perspective of a water resources system,prediction and early warning of drought and flood coupled with numerical simulation and knowledge mining,identification of risk blocking points of drought and flood disaster chain and the adaptive ***,the paper will provide technical support for preventing flood and drought disasters,water resources protection,ecological restoration and climate change adaptation on the Qinghai-Tibet Plateau.

关键词： Drought and flood evolution Monitoring and simulation Prediction and early warning Risk prevention and emergency response Qinghai-Tibet Plateau

An optimal control model with cost effectiveness analysis of Maize streak virus disease in maize plant

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Infectious Disease Modelling 2021年第1期6卷 169-182页

作者： Haileyesus Tessema Alemneh Assefa sintayehu Kassa Anteneh Asmare Godana Department of Mathematics College of Natural and Computational SciencesUniversity of GondarGondarEthiopia Pan African University Institute of Basic Sciences Technology and InnovationNairobiKenya Department of Plant Sciences College of Agriculture and Rural TransformationUniversity of GondarGondarEthiopia Department of Statistics College of Natural and Computational SciencesUniversity of GondarGondarEthiopia

In this paper we formulated and analyzed an optimal deterministic eco-epidemiological model for the dynamics of maize streak virus(MSV)and examine the best strategy to fight maize population from maize streak disease(MSD).The optimal control model is developed with three control interventions,namely prevention(u_(1)),quarantine(u_(2))and chemical control(u_(3)).To achieve an optimal control strategy,we used the Pontryagin’s maximum principle obtain the Hamiltonian,the adjoint variables,the characterization of the controls and the optimality *** simulations are performed using Forward-backward sweep iterative *** findings show that each integrated strategy is able to mitigate the disease in the specified *** due to limited resources,it is important to find a cost-effective *** Incremental Cost-Effectiveness Ratio(ICER)a cost-effectiveness analysis is investigated and determined that the combination of prevention and quarantine is the best cost-effective strategy from the other integrated ***,policymakers and stakeholders should apply the integrated intervention to stop the spread of MSV in the maize population.

关键词： MSV Eco-epidemiological model Optimal control theory Numerical simulation Cost-effectiveness analysis