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Journal of Forestry Research 2009年第1期20卷 31-36页

作者： Shiferaw Alem tadesse woldemariam Ethiopian Institute of Agricultural Research Forestry Research Center P.O. Box 30708 Addis Ababa Ethiopia Addis Ababa University Department of Biology Education P.O.Box 1176 Addis Ababa Ethiopia

Diversity, density and species composition of naturally regenerated woody plants under Eucalyptus grandis plantation and the adjacent natural forest were investigated and compared. Twenty plots, with an area of 20 m × 20 m for each, were established in both of E. grand＆ plantation and adjacent natural forest, independently. In each plot, species name, abundance, diameter and height were recorded. Numbers of seedling were collected in five sub-plots （4 m2） within each major plot. A total of 46 species in the plantation, and 52 species in the natural forest, which belongs to 36 families were recorded. The diversity of species （H＇） is 2.19 in the plantation and 2.74 in the natural forest. The density of understory woody plant was 3842 stems/ha in the plantation and 4122 stems/ha in the natural forest. The densities of seedlings in the natural forest and the plantation were 8101 stems/ha and 4151 stems/ha, respectively. High similarity of woody species composition was found between the natural forest and the plantation. The E. grand＆ plantation was found favoring the regeneration and growth of Millitiaferruginia and Coffea arabica in a much better way than other underneath woody species.

关键词： E. grandis, natural forest natural regeneration plantation woody species diversity

Floristic and structural analysis of the woodland vegetation around Dello Menna,Southeast Ethiopia

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Journal of Forestry Research 2010年第4期21卷 395-408,521页

作者： Motuma Didita Sileshi Nemomissa tadesse woldemariam Gole Sinana Agricultural Research Center Department of Biology Addis Ababa University Environment and Coffee Forest Forum (ECFF)

Floristic composition and vegetation structure were described for the woodland vegetation around Dello Menna, Bale zone, southeast Ethiopia. A total 50 （20 m ×20 m） quadrats were sampled to identify and describe plant community types, species diversity, richness and evenness and to relate the identified plant community types with some environ- mental factors and describe the population structure of woody plant species. In each quadrrat, data on species identity, abundance, height and Diameter at Breast Height （DBH） of woody plant species, altitude and slope were recorded. Vegetation classification was performed using PC - ORD software package. Sorensen＇s similarity coefficient was used to detect dissimilarities among communities. Shannon - Wiener diversity index, species richness and Shannon＇s evenness were computed to de- scribe species diversity of the plant community types. Results show that a total of 171 vascular plant species representing 53 families were re- corded. Fabaceae is the dominant family represented by 13 genera and 26 species （15%） followed by Asteraceae, Lamiaceae and Anacardiaceae with eight species each （4.6%）. Based on the results of vegetation classi- fication, three plant communities （Dalbergia microphylla community, Grewia bicolar- Acacia brevispica community, and Combretum molle- Combretum collinum community） are recognized and described. Species richness, diversity and evenness varied among the plant *** richness and diversity exhibit a bell - shaped pattern along alti- tude. Species turn over among communities more or less follow altitud- inal gradients. Tukey＇s pairwise comparison of means among the plant community types shows significant variations in altitude, implying that altitude is one of the most important factors determining the distribution of plant communities. The community Dalbergia microphylla type exhibits the highest species richness and diversity. Analysis of population structure of the dominant species re

关键词： vegetation structure ty species diversity species richness

Evaluation of soil nutrients under Eucalyptus grandis plantation and adjacent sub-montane rain forest

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Journal of Forestry Research 2010年第4期21卷 457-460,523页

作者： Shiferaw Alem tadesse woldemariam Jindrich Pavlis Mendel University Faculty of Forestry and Wood technology Environment and Coffee Forest Forum

A study was conducted to evaluate the status of soil nutrients under E. grandis plantation in comparison with that in its adjacent submontane rain forest. Twenty sequare plots, with an area of 20 m×20 m for each, were established in both of *** plantation and its adjacent sub-montane rain forest, independently. Soil samples were collected from each square plot, at five points （at the four comers and at the center） of each plot. The collected soil samples were mixed to make a composite and representative sample for each plot, independently. The analyses were done in a soil laboratory following appropriate methods. The analysis result indicated that there were no significance differences between E. grandis plantation and its adjacent sub-montane rain forest in the level of major soil nutrients （total N, available P, exchangeable K, Ca and Mg）, pH and total carbon of soils （p 〈 0.05）. There were significance differences between two sites of forest soils in percentage of clay particles, and exchangeable Na content. E. grandis plantation was found improving soil nutrients and total carbon as compared with that of its adjacent submontane rain forest.

关键词： Eucalyptus grandis plantation rain forest soil nutrients sub-montane

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The Art of The Ages

ChinAfrica 2024年第7期16卷 42-43页

作者： KIRAM tadesse 不详

Ethiopian artist presents the 64 characters of the ancient Chinese classic divination text the I Ching in a series of unique paintings Dawit Muluneh,50,found his calling for painting and sculpture at an early *** and raised in Ethiopia’s capital Addis Ababa,he abandoned the playground and became obsessed with watching his uncle paint.

关键词： raised painting classic

Genomic selection in plant breeding:Key factors shaping two decades of progress

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Molecular Plant 2024年第4期17卷 552-578页

作者： Admas Alemu Johanna Astrand Osval A.Montesinos-López Julio Isidro y Sanchez Javier Fernandez-Gónzalez Wuletaw tadesse Ramesh R.Vetukuri Anders S.Carlsson Alf Ceplitis JoséCrossa Rodomiro Ortiz Aakash Chawade Department of Plant Breeding Swedish University of Agricultural SciencesAlnarpSweden Lantmannen Lantbruk SvalövSweden Facultad de Telematica University de ColimaColimaColima 28040Mexico Centro de Biotecnología y Genómica de Plantas(CBGP UPM-INIA)Universidad Politécnica de Madrid(UPM)-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria(INIA)Campus de Montegancedo-UPM28223 MadridSpain International Center for Agricultural Research in the Dry Areas(ICARDA) RabatMorocco International Maize and Wheat Improvement Center(CIMMYT) Km 45Carretera México-VeracruzTexcocoMéxico 52640Mexico

Genomic selection,the application of genomic prediction(GP)models to select candidate individuals,has significantly advanced in the past two decades,effectively accelerating genetic gains in plant *** article provides a holistic overview of key factors that have influenced GP in plant breeding during this *** delved into the pivotal roles of training population size and genetic diversity,and their relationship with the breeding population,in determining GP *** emphasis was placed on optimizing training population *** explored its benefits and the associated diminishing returns beyond an optimum *** was done while considering the balance between resource allocation and maximizing prediction accuracy through current optimization *** density and distribution of single-nucleotide polymorphisms,level of linkage disequilibrium,genetic complexity,trait heritability,statistical machine-learning methods,and non-additive effects are the other vital *** wheat,maize,and potato as examples,we summarize the effect of these factors on the accuracy of GP for various *** search for high accuracy in GP—theoretically reaching one when using the Pearson’s correlation as a metric—is an active research area as yet far from optimal for various *** hypothesize that with ultra-high sizes of genotypic and phenotypic datasets,effective training population optimization methods and support from other omics approaches(transcriptomics,metabolomics and proteomics)coupled with deep-learning algorithms could overcome the boundaries of current limitations to achieve the highest possible prediction accuracy,making genomic selection an effective tool in plant breeding.

关键词： genomic selection genetic gain genomic prediction optimization deep learning training population optimization

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埃塞俄比亚自然保护地建设管理现状及启示

世界林业研究 2024年第4期37卷 98-104页

作者：李奥 Takele tadesse 李鸣 Tamirat Solomon 尹心安王昌海中国社会科学院大学政府管理学院沃莱塔索多大学健康科学与医学学院中国社会科学院大学国际政治经济学院沃莱塔索多大学自然资源管理系北京师范大学环境学院中国社会科学院农村发展研究所

自然保护地的有效管理对于保护生物多样性、维持生态系统平衡和保障人类可持续发展具有重要意义。文中以埃塞俄比亚自然保护地为研究对象，在介绍其自然保护地建设概况的基础上，从管理政策、管理体制和相关机构3个方面梳理其自然保护... 详细信息

自然保护地的有效管理对于保护生物多样性、维持生态系统平衡和保障人类可持续发展具有重要意义。文中以埃塞俄比亚自然保护地为研究对象，在介绍其自然保护地建设概况的基础上，从管理政策、管理体制和相关机构3个方面梳理其自然保护地管理体系，围绕面临的挑战和潜在的机遇分析其自然保护地建设管理现状，最后从积极探索保护地新型治理机制、建立健全特许经营制度和重视社区共管机制建设3个方面总结埃塞俄比亚自然保护地建设管理对我国的启示。

关键词：自然保护地生物多样性管理体系生态旅游治理机制特许经营制度社区共管机制埃塞俄比亚

Multidirectional 3D printed functionally graded modular joint actuated by TCPFL muscles for soft robots

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Bio-Design and Manufacturing 2019年第4期2卷 256-268页

作者： Armita Hamidi Yara Almubarak Yonas tadesse Humanoid Bio-robotics and Smart Systems(HBS)LaboratoryMechanical Engineering DepartmentThe University of Texas at DallasRichardsonTX 75080USA

Highly deformable bodies are essential for numerous types of applications in all sorts of environments. Joint-like structures comprising a ball and socket joint have many degrees of freedom that allow mobility of many biomimetic structures. Recently, soft robots are favored over rigid structures for their highly compliant material, high-deformation properties at low forces, and ability to operate in di fficult environments. However, it is still challenging to fabricate complex designs that satisfy application constraints due to the combined e ffects of material properties, actuation method, and structural geometry on the performance of the soft robot. Therefore, a combination of a rigid joint and a soft body can help achieve modular robots with fully functional body morphology. Yet, the fabrication of soft parts requires extensive molding for complex shapes, which comprises several processes and can be time-consuming. In addition, molded connections between extremely soft materials and hard materials can be critical failing points. In this paper, we present a functionally graded 3D-printed joint-like structure actuated by novel contractile actuators. Functionally graded materials (FGMs) via 3D printing allow for extensive material property enhancement and control which warrant tunable functionalities of the system. The 3D-printed structure is made of 3 rigid ball and socket joints connected in series and actuated by integrating twisted and coiled polymer fishing line ( TCPFL) actuators, which are con fined in the FGM accordion-shaped channels. The implementation of the untethered T CPFL actuation system can be highly bene ficial for deployment in environments that require low vibrations and silent actuation. The fishing line TCP actuators produce an actuation strain up to 40% and bend the joint up to 40° in any direction. The T CPFL can be actuated individually or as a group to control the bending trajectory of the modular joint, which is bene ficial when deployed i

关键词： Functionally graded 3D-printed Joint Multidirectional Fishing line TCP

Perceptions and attitudes of local people towards participatory forest management in Tarmaber District of North Shewa Administrative Zone, Ethiopia: the case of Wof-Washa Forests

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Ecological Processes 2017年第1期6卷 168-183页

作者： Solomon Ayele tadesse Demel Teketay Department of Natural Resources Management College of Agriculture and Natural Resource SciencesDebre Berhan UniversityP.O.Box 445Debre BerhanEthiopia Department of Crop Science and Production Botswana University of Agriculture and Natural ResourcesPrivate Bag 0027GaboroneBotswana

Introduction:Since the last few decades,the government of Ethiopia has introduced and adopted participatory forest management(PFM)in different regions of the ***,there is a lack of research dealing with perceptions and attitudes of local people towards PFM in Wof-Washa Forests(WWF).The aim of this study was to evaluate the perceptions and attitudes of local people towards PFM implemented in *** hypothesized that the perceptions and attitudes of local people towards PFM differ with socio-economic variables,such as sex,age,level of education,family size,occupation type,annual income,length of duration of local residence,livestock,and land ***:A structured questionnaire comprised of close-and open-ended questions was developed and administered to a total of n=64 households to collect information on the perceptions and attitudes of local people towards PFM in *** statistics and multiple linear regressions were used to analyze and interpret the ***:The results revealed that socio-economic variables had significant effects on the perceptions towards“the prevalence of the problems with the existing PFM system”(39%variance explained),“the concept of PFM”(30%variance explained),and“the presence of PFM practice”(11%variance explained).Majority of the respondents accepted the PFM program introduced in WWF in order to protect and manage the *** study also revealed that socio-economic variables had significant effects on the attitudes towards“managing forests via participatory approach”(16%variance explained),“having the responsibility to protect the WWF”(40%variance explained),and“accepting the PFM practice”(54%variance explained).However,the findings suggested that there were some respondents who were yet unsure to fully accept the concept and practice of ***:Creating public awareness about PFM is crucial to alleviate the problems of deforestation and reduce the unsustainable use of the *** socio-economic var

关键词： Deforestation Respondents Socio-economic variables Structured questionnaire Wof-Washa Forests

Prediction of sedimentation in reservoirs by combining catchment based model and stream based model with limited data

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International Journal of Sediment Research 2019年第1期34卷 27-37页

作者： Abebe tadesse Wenhong Dai Hohai University Department of Water Conservancy and Hydropower Engineering

Estimation of sedimentation in reservoirs helps in the management and design of the reservoir's useful capacity. This research was done on the Awash River basin at the Koka Dam Reservoir in Ethiopia. The method applied was the loose integration of the Soil and Water Assessment Tool(SWAT) model and Hydrologic Engineering Center-River Analysis System(HEC-RAS) model for the estimation of the sediment load reaching the reservoir. The SWAT model was used for the estimation of erosion at the catchment level,and the HEC-RAS model was applied to estimate the sediment transport in the river channel. The implemented method allows sedimentation in the floodplains and bed shear stress to be considered in the sediment modeling, which cannot be considered in the SWAT model. In addition, the river cross sectional properties and the hydrodynamic processes in the rivers were considered in the modeling process. The data used in this study are a combination of i) observed data collected by government agencies, ii) data available online in data repositories, and iii) data extracted from remote sensing in the Shuttle Radar Topographic Mission(SRTM) Digital Elevation Model(DEM). The calibration and validation of the SWAT model was done by using Sequential Uncertainty Fitting(SUIF-2) calibration and validation tools. The HEC-RAS model was calibrated by adjusting the roughness factor. The output from the integrated approaches gives better estimates of flow and sediment near the inlet to the reservoir, with coefficients of determination of 0.85 and 0.67, respectively, and Nash Sutcliffe coefficients of model fit efficiency of 0.90 and 0.62, respectively, for daily simulations.

关键词： Reservoir sedimentation Awash River SWAT HEC-RAS Rating curve

Camel management as an adaptive strategy to climate change by pastoralists in southern Ethiopia

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Ecological Processes 2017年第1期6卷 273-284页

作者： Galma Wako Menfese tadesse Ayana Angassa Wondo-Genet College of Forestry and Natural Resource Hawassa UniversityShashamaneEthiopia Department of Animal Science and Production Botswana University of Agriculture and Natural ResourcesGaboroneBotswana

Introduction:Experiences of low rainfall and frequent droughts have had enormous impacts on livestock production and pastoralists’livelihoods in southern *** Borana pastoralists are dependent on livestock husbandry with the dominance of cattle in their herds for ***,the Borana communities have engaged in extensive livestock species diversification,with more focus on camel management as an adaptation strategy to the severity of recurrent *** increasing interests in camel management among the Borana pastoralists are acknowledged,the driving forces for the increase in camel population in the region have not been *** aim of this study was to assess the trend in camel management as an adaptation strategy towards climate change among the Borana pastoral *** study also investigated evidence of climate change and the driving factors for camel ***:The study was conducted in three purposively selected kebeles,which is a lower administrative unit in Ethiopia,of Yabello district in Borana Zone in southern Ethiopia focusing on 156 randomly selected camel-owning *** study employed both quantitative and qualitative methods whereby data gathering tools such as key informant interviews(KII),focus group discussions(FGD),household surveys(HS),and field observations were *** data were analyzed by descriptive statistics using SPSS software version ***:Pastoralists’perceptions and the existing meteorological data analysis showed an increasing trend in temperature but a decreasing pattern in rainfall over the last 27 years(i.e.,during the last four Gada periods).Both pastoralists’observations and existing meteorological data analysis showed an increasing incidence of recurrent droughts with decreasing availability of grazing and water *** further explained that cattle are more vulnerable during severe *** findings also showed that camel management as an adaptation st

关键词： Climate change Camel management Pastoral households Borana Zone Southern Ethiopia