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Mechanisms of bush encroachment and its inter-connection with rangeland degradation in semi-arid African ecosystems:a review

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Journal of Arid Land 2017年第2期9卷 299-312页

作者： anteneh BELAYNEH Zewdu K TESSEMA Department of Biology College of Natural and Computational Sciences Haramaya University Haramaya 282 Ethiopia Rangeland Ecology and Biodiversity Program School of Animal and Range Sciences College of Agriculture and Environmental Sciences Haramaya University Dire Dawa 138 Ethiopia

Many studies show that semi-arid rangelands throughout the world have been rapidly converted from a grassland state to a bush encroachment state during the past 50 years. Bush encroachment includes the spread of local woody species and/or incursion of woody species introduced from other ecosystems into semi-arid savannas and grassland ecosystems. Rangeland degradation due to bush encroachment causes several challenges, affecting the production of livestock and pastoral people livelihoods in most parts of Africa. Scientists have long been attempting to develop schematic and mathematical theories to explain the observed phenomenon of bush encroachment, and several theories were proposed and developed. The well-regarded theories include：（1） Waiter＇s two-layer model, （2） Moir＇s one-layer model, （3） state-and-transition theory, （4） equilibrium theory, （5） disequilibrium theory, and （6） non-equilibrium theory. Within those theories, the most frequently-indicated driving factors that explain bush encroachment include over-grazing, availability of soil nutrient and moisture, elevated CO2 levels, frequency and intensity of fire, spread of seeds of woody species by livestock and wild animals. It should be stressed that couplings and interactions among diverse driving factors are more often at work in determining the condition of bush encroachment. To summarize, the effort in managing semi-arid ecosystems needs critical knowledge to understand the cause-effect relationships of underlying factors through integrated approach. Therefore, future research on encroachment of woody plants should be multi-discipline oriented and multi-partnership involved.

关键词： climate change exotic woody species indigenous woody species Moir's one-layer model rangelandtheories Walter's two-layer model

Modeling the distribution of Aloe ankoberensis and A. debrana under different climate change scenarios in North Shewa Zone, Amhara National Regional State, Ethiopia

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Ecological Processes 2024年第2期13卷 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

关键词： Biodiversity Endemic Aloe Environmental variable Habitat suitability Species distribution Species extinction

Valuing the water supply: ecosystem-based potable water supply management for the Legedadie-Dire catchments, Central Ethiopia

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Ecological Processes 2019年第1期8卷 104-127页

作者： Yilikal anteneh Gete Zeleke Ephrem Gebremariam Water and Land Resource Center(WLRC) Addis Ababa University3880 Addis AbabaEthiopia Chair of Environmental Planning and Landscape Design Addis Ababa UniversityAddis AbabaEthiopia

Background:There is a substantial interest in the values that consumers place on drinking water quality and *** resources are crucial to improving the urban potable water supply in developing countries that are characterized by low-cost recovery rates and a high and rapidly growing demand for more reliable *** study examined households’willingness to pay(WTP)for the improvement of water services by identifying their water choice decisions and the mode of water supply that they prefer the water supply authority to use among several alternative water supply ***-preference data were collected from 322 randomly selected households in Addis Ababa,who were presented with three sets of choices(three alternative bundle choices,including the reference scenario).The data were analyzed using the mixed logit WTP space *** approaches to modeling the distribution of WTP(fixed,uncorrelated,and correlated)using mixed logit WTP space models were ***:Three-quarters of the households agreed to contribute money toward ecosystem-based water supply management(EBWSM)intervention programs on a monthly *** average contribution that the respondents were willing to pay was 150.5 Ethiopian Birr(ETB)as a one-off lump sum to kick off the EBWSM *** of the respondents chose a bundle of water supply options that provides risk-free and high-quality water with no months of shortages than moderate water quality that is safe to drink and palatable with 1 month shortages *** implies that households would need to be supplied with risk-free,high-quality water without interruption at an appropriate flow *** model with correlations fitted the data well with the highest simulated log-likelihoods at convergence and gave the best estimate of the households’WTP for water *** 46%of the sampled households were willing to pay more than 33 ETB per month,and 49%of the households were willing to pay between 21 E

关键词： Ecosystem service Water supply Mixed logit WTP-space model Catchment management Legedadie reservoir

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

Preparation of large,ultra-flexible and free-standing nanomembranes of metal oxide-polymer composite and their gas permeation properties

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Clean Energy 2017年第1期1卷 80-89页

作者： anteneh Mersha Roman Selyanchyn Shigenori Fujikawa Graduate School of Engineering Kyushu UniversityFukuoka 819-0395Japan WPI International Institute for Carbon-Neutral Energy Research(WPI-I2CNER) Kyushu UniversityFukuoka 819-0395Japan Center for Molecular Systems(CMS) Kyushu UniversityFukuoka 819-0395Japan Laboratory for Chemistry and Life Science Tokyo Institute of Technology4259 NagatsutachoMidori-kuYokohama226-8503Japan

In this work,fabrication of free-standing nanomembranes of metal oxide(MO_(x))and polymers by simple spin-coating method is ***,double-layer nanomembranes containing MO_(x) and epoxy resin of polyethyleneimine and poly[(o-cresyl glycidyl ether)-co-formaldehyde]were ***-standing nanomembranes were successfully prepared,but defects formed in the metal oxide nanolayer during sharp bending of the *** overcome fragility of MO_(x) nanolayer,poly(vinyl alcohol)nanolayers were introduced between MO_(x) nanolayers by layer-by-layer(LbL)assembly *** LbL nanomembrane was also free-standing and was highly flexible during macroscopic membrane *** after transfer of the LbL nanomembrane onto a porous support,it did not have apparent cracks,confirmed by scanning electron microscopy(SEM).The LbL nanomembrane sustained low gas permeance,confirming the absence of significant defects,although it shows excellent *** believe that the presented LbL nanomembrane could be a platform useful for the design of molecular nanochannels,which is the next challenge for efficient gas separation.

关键词： nanomembranes free-standing film ultrathin film layer-by-layer assembly metal oxide gas permeation

Ocular manifestation and their associated factors among HIV/AIDS patients receiving highly active antiretroviral therapy in Southern Ethiopia

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International Journal of Ophthalmology(English edition) 2017年第5期10卷 776-781页

作者： anteneh Amsalu Kindie Desta Demiss Nigussie Demoze Delelegne Department of Medical Microbiology School of Biomedical and Laboratory Sciences College of Medicine and Health Sciences University of Gondar Gondar P.O.box 196 Ethiopia School of medicine College of Medicine and Health SciencesHawassa University Hawassa EO.box 1560 Ethiopia Department of Medical Laboratory Science College of Medicine and Health Sciences Hawassa University Hawassa RO.box 1560 Ethiopia

AIM：To assess the pattern of ocular manifestation and associated factors among human immunodeficiency virus（HIV）/acquired immunodeficiency syndrome（AIDS） patients on highly active antiretroviral therapy（HAART） at Hawassa University Referral Hospital, Southern Ethiopia. METHODS：A cross sectional study was conducted from January 2014 to April 2015. After obtaining informed written consent, 240 adult HIV/AIDS patients on HAART were randomly selected regardless of their ophthalmic symptoms, WHO status or CD4 count. Data were collected using structured questionnaires and ophthalmologic clinical examination. Data were entered and analyzed using SPSS version 20.0 software. RESULTS：The mean duration of HAART was 62.5mo. The prevalence of HIV related ocular manifestation was 14.2%. Seborrheic blepharitis（5%） was the most common ocular manifestation, followed by squamoid conjunctival growth（3.8%）. The rate of ocular manifestation was significantly higher among study participants who had CD4＋ count 〈200 cells/μL（AOR=3.83; 95%CI：1.315-11.153）, low duration of HAART（AOR=3.0; 95%CI：1.305-6.891） and who had primary school education [odds ratio（OR） =2.8; 95%CI：1.105-7.099]. Prevalence of visual impairment and blindness was 10.9% and 5.8%, ***：HAART may be the reason for the decline in the prevalence of ocular manifestation in HIV/AIDS patients in the study area. Ophthalmologic screening of HIV/AIDS patients, especially those with CD4 counts of 〈200/μL cells and in the first five years of HAART followup is recommended to reduce visual impairment and/or blindness.

关键词： human immunodeficiency virus acquired immunodeficiency syndrome ocular manifestation highlyactive antiretroviral therapy

Utilization of the superior properties of highly mesoporous PVP modified NiCo_2O_4 with accessible 3D nanostructure and flower-like morphology towards electrochemical methanol oxidation reaction

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Journal of Energy Chemistry 2019年第2期28卷 136-146页

作者： Gracita M.Tomboc Medhen W.Abebe anteneh F.Baye Hern Kim Department of Energy Science and Technology Smart Living Innovation Technology CenterMyongji University

Up to this date,researchers are still facing difficulties to expand the technology of direct methanol fuel cells(DMFCs) because of the high overpotential required to oxidize the methanol and its relatively poor performance due to CO poisoning of the leading-high cost anode *** line with this,we have successfully modified the morphological structure and composition of low cost cobalt based-metal oxides,MCo_2O_4(M = Zn and Ni),with the simple and noble use of polyvinyl pyrrolidone(PVP) as growth modifier and surface stabilizer during the synthesis of nanoparticles in our previous reports,which shown high electrocatalytic activity and strong *** to the good performance of our PVP modified MCo_2O_4 towards pseudocapacitor and oxygen evolution reaction applications,we decided to extend our research study to methanol oxidation ***,PVP modified Ni Co_2O_4 electrode directly grown on nickel foam substrate via a simple hydrothermal process exhibited better performance compared with PVP modified ZnCo_2O_4 and NiCo_2O_4 without *** had obtained a remarkably low onset potential of 0.285 V and high current density of 280 m A cm^(-2),and shown great stability and high poison tolerance during a continuous CV cycling and Chronoamperometry test,which attained high efficiency of 86.86%and 98.52%,*** positive results of PVP modified Ni Co_2O_4 electrode towards MOR might be attributed to its hierarchical 3 D nanostructures with highly mesoporous surface and large surface area which may have provided numerous electroactive sites,and the exceptional corrosion stability of Ni Co_2O_4 electrode in alkaline solution.

关键词： NiCo2O4 3D nanostructure Electrochemical Methanol oxidation Current density

Does community-based health insurance affect lifestyle and timing of treatment seeking behavior?Evidence from Ethiopia

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Global Health Journal 2024年第2期8卷 83-90页

作者： Zecharias Fetene anteneh Anagaw D.Mebratie Zemzem Shigute Getnet Alemu Arjun S.Bedi Center for Health Economics University of YorkYorkUnited Kingdom School of Public Health College of Health SciencesAddis Ababa UniversityAddis AbabaEthiopia International Institute of Social Studies Erasmus University Rotterdamthe Haguethe Netherlands Institute of Development and Policy Research Addis Ababa UniversityAddis AbabaEthiopia

Objectives This paper aims to investigate the effects of enrollment in the Ethiopian community-based health insurance(CBHI)scheme on household preventive care activities and the timing of treatment-seeking behavior for illness *** is growing concern about the financial sustainability of CBHI schemes in developing ***,few empirical studies have identified potential contributors,including ex-ante and ex-post moral *** We implement a household fixed-effect panel data regression model,drawing on three rounds of household survey data collected face to face in districts where CBHI scheme is operational and in districts where it is not operational in *** The findings show that enrolment in CBHI does not significantly influence household behaviour regarding preventive care activities such as water treatment before drinking and handwashing before ***,CBHI significantly increases delay in treatment-seeking behaviour for diseases ***,on average,we estimate about 4-6 h delay for malaria symptoms,a little above 4 h for tetanus,and 10-11 h for tuberculosis among the insured *** While there is evidence that CBHI improve the utilization of outpatient or primary care services,our study suggests that insured members may wait longer before visiting health *** delay could be partly due to moral hazard problems,as insured households,particularly those from rural areas,may consider the opportunity costs associated with visiting health facilities for minor ***,it is essential to identify the primary causes of delays in seeking medical services and implement appropriate interventions to encourage insured individuals to seek early medical attention.

关键词： Community-based health insurance Financial sustainability Preventive care Treatment-seeking behavior Household fixed effect Ethiopia

埃塞俄比亚侨民在国家形象建设中的作用 ——以埃塞俄比亚人在美国为例

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埃塞俄比亚侨民在国家形象建设中的作用 ——以埃塞俄比亚人在美...

作者： anteneh Fentaw Abebe 吉林大学

学位级别：硕士

自20世纪70年代起,埃塞俄比亚人开始大量移居海外。据埃塞俄比亚政府的统计,全世界有超过300万埃塞俄比亚人,分布在美国、澳大利亚、欧洲、南非、中东、新西兰等地区。他们中的绝大多数生活在美国、中东、欧洲、以色列、苏丹、肯尼亚、... 详细信息

自20世纪70年代起,埃塞俄比亚人开始大量移居海外。据埃塞俄比亚政府的统计,全世界有超过300万埃塞俄比亚人,分布在美国、澳大利亚、欧洲、南非、中东、新西兰等地区。他们中的绝大多数生活在美国、中东、欧洲、以色列、苏丹、肯尼亚、南非和吉布提。仅在美国,就有50多万埃塞俄比亚人永久居住。与世界各地的同胞一样,在美国的埃塞俄比亚侨民非常积极地参与其母国的事务。他们通过公民俱乐部、宗教机构、政治集会、体育节日、示威、成立的公司和游说团体,以及政治、经济和人道主义参与,广泛地推广埃塞俄比亚的历史、文化和现实。埃塞俄比亚政府高度重视其2002年的外交政策,各种侨民的宣言,以及2012年的侨民政策等,并建立了各种制度以改善埃塞俄比亚侨民对于母国的经济、政治、社会和外交的整体发展所做出的贡献,并且进一步保护他们在东道国的权利。本文试图研究埃塞俄比亚侨民在其所在国,尤其是美国,通过政治家、国际媒体和国际组织改善他们的形象时所扮演的角色。本文旨在回答下列研究问题:埃塞俄比亚侨民期望在美国塑造何种角色?其成效如何?对于埃塞俄比亚侨民增强国家形象塑造方面有何种建议?基于这些研究问题,作者试图评估埃塞俄比亚人以及居住在国外的埃塞俄比亚裔的整体现实,以及埃塞俄比亚政府为使其国外公民在公共外交和形象塑造中扩大参与所做出的种种努力,并且寻找出阻碍在美国的埃塞尔比亚侨民充分支持其政府改进埃塞俄比亚目前整体形象以及其在国际舞台上的合适定位的因素。在研究方法方面,作者使用了定性研究和定量研究混合的研究方法来回答本文的研究问题。使用该方法的原因是因为混合研究可以全面掌握本研究问题。更重要的是,定性分析法给出了来自关键信息提供者的一些深度信息,这些信息包括制度障碍以及在美国的埃塞俄比亚侨民可以有效参与其母国的国家形象发展的预期机会。本文使用一手和二手资料汇编数据,以便对该问题进行简要分析。总部设在亚的斯亚贝巴的埃塞俄比亚侨民机构、埃塞俄比亚侨民协会的成员和一名居住在美国的侨民协会的成员作为关键信息提供者接受了采访。二手资料来源于公共政策,国家形象建设,侨民在其母国整体发展中的角色,以及在美国的埃塞俄比亚人。此外还源于书籍、既有研究文献、期刊杂志、新闻发布会、媒体报道,如报纸、在线新闻、网站博客和其他有关公共政策、国家形象建设的相关文件等。本文通过访谈(关键信息提供者访谈)、问卷调查和文献分析来收集相关和不同类型的数据,并回答研究目标。总的分析包括定性数据和描述性统计数据,如均值和标准差。本研究的结构分为五章。第一章是研究的介绍部分,分别包括研究背景、研究问题、主要论证(研究问题的答案)、研究方法、研究意义、文献综述和论文结构。本研究的结论希望有助于更好地理解形象塑造,以及埃塞俄比亚移民在整体发展中的作用,特别是在公共外交方面,并吸引埃塞俄比亚人和在美国的埃塞俄比亚侨民改善国家的形象,探讨埃塞俄比亚侨民参与的阻碍和机会,并寻找改善东道国和原籍国之间双边关系的方法。第二章介绍了埃塞俄比亚移民人口的概况和现状、国家政府的参与策略以及埃塞俄比亚国家形象塑造所涉及的领域。本章论述了埃塞俄比亚人在不同政治时期的全球侨民的历史,特别是在过去的15年里他们在美国的定居情况,以及他们的总体现状。此外,本文也力图解释政府在制度和立法方面做出的各种努力,以便更好的利用他们的潜力,并且强调了埃塞俄比亚侨民为了其母国变得更好,在经济(汇款、侨民投资、购买债劵)、社会、政治、知识和以及专业技能方面扮演的中间角色。第三章试图描述国家形象的众多维度,如果操作正确就可以达到成倍的效果。国家形象的建设可以加强其在世界范围内的影响,同时创造国际政治支持。后者在今天看来更为重要,因为各国都希望融入全球市场,参与全球政治,并提高其在全球舞台上的声誉。其他国家如何看待和描绘另一个国家将影响多边关系以及战略行动。此外本章还描述了埃塞俄比亚当前的形象,这是由于历史上的饥荒,内战和政治上的不稳定导致的。除此之外,埃塞俄比亚具有自然和历史旅游景点、非殖民爱国主义历史、丰富的自然资源,宗教宽容性和多样性,以及当前的经济成就,并且在建立国际联盟、联合国以及非洲联盟中发挥了重要作用。本章还解释和评估了国家政府和一般公众为恢复埃塞俄比亚昔日形象的荣耀所做的努力。第四章讨论了在美国的埃塞俄比亚人如何通过组织各种活动和节日、示威、游说美国政客和正在建设的公司来帮助建设他们国家的形象,所有这些行动都对两国的政治和经济关系产生了重大影响。众多的人口和经济影响力促使华盛顿特区市议会将该市的一条街道重新命名为“小埃塞俄比亚”。然而另一方面,这一章阐述了埃塞俄比亚侨民由于宗教和种族导致的分散性,他们拒绝支持成为一个强有力的民族。实际上与事实相反的是,他们引发种族和宗教冲突,或者致力于歪曲和误导美国公众和政治家。第五章总结本研究并提出建议。障

关键词：埃塞俄比亚侨民美国埃塞俄比亚侨民埃塞俄比亚侨民政策形象塑造公共外交