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| 1 | Elevational changes in vascular plants richness, diversity, and distribution pattern in Abune Yosef mountain range, Northern Ethiopia显示文摘The aim of this research is to investigate the patterns of vascular plant species richness,diversity,and distribution along an elevation gradient in the Abune Yosef mountain range,Ethiopia.Preferential systematic sampling was employed to collect vegetation and environmental data along the elevation gradient.We found that plant species richness declines monotonically from low to high elevations.Specifically,vascular plant species richness and diversity were lower in the Afroalpine grassland(high elevation)than in the Dry evergreen Afromontane forest and Ericaceous forest(low elevations).In contrast,endemic vascular plant richness was significantly higher in the Afroalpine grassland than in the Dry evergreen Afromontane forest and Ericaceous forest.Elevation showed a significant impact on the richness,diversity,and endemism of vascular plants.According to Sorensen's coefficient,the similarity between Dry evergreen Afromontane forest and Ericaceous forest vegetation types is higher(32%)than the similarity between Ericaceous forest and Afroalpine grassland(18%).Only 5%similarity was recorded between the Dry evergreen Afromontane forest and Afroalpine grassland.Growth forms showed different elevationai richness patterns.Trees and liana increased monotonically up to 3300 m.Shrub and herb richness patterns followed a hump-shaped and inverted hump-shaped pattern along the elevation gradient.The elevation patterns of vascular plant species richness,diversity,and growth form in the present study may be attributed to differences in management intensity,spatial heterogeneity,microclimatic variations,and anthropogenic disturbances. | Kflay Gebrehiwot Sebsebe Demissew Zerihun Woldu Mekbib Fekadu Temesgen Desalegn Ermias Teferi | 2019 | Plant Diversity2019，41，4： | 5 |
| 2 | Modeling the influence of ethanol on the adsorption and desorption of selected BTEX compounds on bentonite and kaolin显示文摘The influence of ethanol on the adsorption capacity and desorption kinetics of benzene and toluene on bentonite and kaolin through modeling and experimental study was investigated.The results showed that the adsorption capacity of both soils for the target compounds decreased as ethanol content increased.As ethanol content increased from 0 to 50%,the adsorption capacity for benzene and toluene on bentonite decreased from 3.6 to 0.54 μg n+1 /(L n ·g) (by 85%) and 1.91 to 0.01 μg n+1 /(L n ·g) (by 99.5%),respectively.For benzene and toluene adsorption on kaolin,the adsorption capacity decreased by 86.5% (from 0.26 to 0.04 μg n+1 /(L n ·g) and 98.2% (from 0.13 to 0.002 μg n+1 /(L n ·g)),respectively,as ethanol content increased from 0 to 50%.In addition,the desorption rate of benzene and toluene from bentonite decreased by about one order of magnitude as the ethanol increased from 0 to 25% and 0 to 50%,respectively.It can be inferred that ethanol could affect the effectiveness of natural attenuation processes that rely on adsorption to soils as a containment technique for benzene and toluene by retarding the adsorption to soils and remobilizing compounds that had already been adsorbed to soils. | Temesgen Garoma Lacy Skidmore | 2011 | Journal of Environmental Sciences2011，23，11： | 4 |
| 3 | Yield stability and relationships among stability parameters in faba bean(Vicia faba L.) genotypes显示文摘Sixteen faba bean genotypes were evaluated in 13 environments in Ethiopia during the main cropping season for three years(2009–2011). The objectives of the study were to evaluate the yield stability of the genotypes and the relative importance of different stability parameters for improving selection in faba bean. The study was conducted using a randomized complete block design with four replications. G × E interaction and yield stability were estimated using 17 different stability parameters. Pooled analysis of variance for grain yield showed that the main effects of both genotypes and environments, and the interaction effect, were highly significant(P ≤ 0.001) and(P ≤ 0.01), respectively. The environment main effect accounted for 89.27% of the total yield variation, whereas genotype and G × E interaction effects accounted for 2.12% and 3.31%, respectively.Genotypic superiority index(Pi) and FT3 were found to be very informative for selecting both high-yielding and stable faba bean genotypes. Twelve of the 17 stability parameters,including CVi, RS, α, λ, S2 di, bi, S(2)i, Wi, σ2i, EV, P59, and ASV, were influenced simultaneously by both yield and stability. They should accordingly be used as complementary criteria to select genotypes with high yield and stability. Although none of the varieties showed consistently superior performance across all environments, the genotype EK 01024-1-2ranked in the top third of the test entries in 61.5% of the test environments and was identified as the most stable genotype, with type I stability. EK 01024-1-2 also showed a17.0% seed size advantage over the standard varieties and was released as a new variety in2013 for wide production and named 'Gora'. Different stability parameters explained genotypic performance differently, irrespective of yield performance. It was accordingly concluded that assessment of G × E interaction and yield stability should not be based on a single or a few stability parameters but rather on a combination of stability parameters. | Tamene Temesgen Gemechu Keneni Tadese Sefera Mussa Jarso | 2015 | The Crop Journal2015，3，3： | 3 |
| 4 | Effect of Vachellia tortilis on understory vegetation,herbaceous biomass and soil nutrients along a grazing gradient in a semi-arid African savanna显示文摘The spatial pattern and abundance of herbaceous vegetation in semi-arid savannas are dictated by a complex and dynamic interaction between trees and grasses. Scattered trees alter the composition and spatial distribution of herbaceous vegetation under their canopies. Therefore, we studied the effect of Vachellia tortilis on herbaceous vegetation composition, biomass and basal area, and soil nutrients on sites with varying grazing intensities in the central rift valley of Ethiopia. Data were collected on species composition, cover and biomass of herbs and grasses, and soil moisture and nutrient contents under light,medium, and heavy grazing pressures, both under the inside and outside of V. tortilis canopies. Species richness was similar in both locations but decreased with increased grazing. Only the overall biomass and herb cover were significantly greater under the canopy than outside, and overall biomass showed significant unchanging decline with increased grazing. However, vegetation cover was significantly greater on moderately grazed sites compared to low and heavily grazed sites. All soil variables were significantly higher under V. tortilis canopies than outside.Our findings suggest that V. tortilis has more effect on composition and diversity of herbaceous vegetation than on species richness, and that V. tortilis promotes the herbaceous layer biomass by reducing soil moisture loss and increasing soil fertility under the inside than outside the canopies. Therefore, we suggest that management practices should be directed on reducing pressure on V. tortilis by regulating grazing. Low to moderate grazing levels(i.e., a stocking rate less than 39.6 TLU ha^(-1) yr^(-1)) seems to be tolerable to ensure sustainable conservation of the species in the study area in particular and in semi-arid savannas in general. | Temesgen Yadeta Elmar Veenendaal Karle Sykora Zewdu K.Tessema Addisu Asefa | 2018 | Journal of Forestry Research2018，29，6： | 3 |
| 5 | Evaluation of sampling strategies to estimate crown biomass显示文摘Background:Depending on tree and site characteristics crown biomass accounts for a significant portion of the total aboveground biomass in the tree.Crown biomass estimation is useful for different purposes including evaluating the economic feasibility of crown utilization for energy production or forest products,fuel load assessments and fire management strategies,and wildfire modeling.However,crown biomass is difficult to predict because of the variability within and among species and sites.Thus the allometric equations used for predicting crown biomass should be based on data collected with precise and unbiased sampling strategies.In this study,we evaluate the performance different sampling strategies to estimate crown biomass and to evaluate the effect of sample size in estimating crown biomass.Methods:Using data collected from 20 destructively sampled trees,we evaluated 11 different sampling strategies using six evaluation statistics:bias,relative bias,root mean square error(RMSE),relative RMSE,amount of biomass sampled,and relative biomass sampled.We also evaluated the performance of the selected sampling strategies when different numbers of branches(3,6,9,and 12)are selected from each tree.Tree specific log linear model with branch diameter and branch length as covariates was used to obtain individual branch biomass.Results:Compared to all other methods stratified sampling with probability proportional to size estimation technique produced better results when three or six branches per tree were sampled.However,the systematic sampling with ratio estimation technique was the best when at least nine branches per tree were sampled.Under the stratified sampling strategy,selecting unequal number of branches per stratum produced approximately similar results to simple random sampling,but it further decreased RMSE when information on branch diameter is used in the design and estimation phases.Conclusions:Use of auxiliary information in design or estimation phase reduces the RMSE produced by a sampling strategy.However,this is attained by having to sample larger amount of biomass.Based on our finding we would recommend sampling nine branches per tree to be reasonably efficient and limit the amount of fieldwork. | Krishna P Poudel Hailemariam Temesgen Andrew N Gray | 2015 | Forest Ecosystems2015，2，1： | 2 |
| 6 | An individual-tree mortality model for complex stands of southeastern British Columbia 显示文摘 | TEMESGEN H MITCHELL S J | 2005 | Western Journal of Applied Forestry2005，2，20： | 1 |
| 7 | Interleukin-2 therapy and CD4 +T cells in HIV-1 infection 显示文摘 | Vento S CaineUi F Temesgen Z | 2006 | Lancet2006，367，： | 1 |
| 8 | Lung infections after cancer chemotherapy显示文摘 | Vento S Cainelli F Temesgen Z | 2008 | Lancet Oncol2008，9，10： | 1 |
| 9 | Natural hazard assess- ment using G1S and remote sensing methods,with particular refer- ence to the landslides in the Wondogenet area, Ethipia 显示文摘 | Temesgen B Mohammed M U Korme T | 2001 | Physics and Chemistry of the Earth Part C : Solar Terrestrial & Planetary Science2001，26，9： | 1 |
| 10 | Removal of sulfadiazine,sulfamethizole,sulfamethoxazole,and sulfathiazole from aqueous solution by ozonation显示文摘 | Temesgen Garoma Shyam K Umamaheshwar Alison Mumper | 2010 | Chemosphere2010，79，： | 1 |
| 11 | Antiretrovirals显示文摘 | Wright AJ | 1999 | Mayo Clin Proc1999，74，： | 1 |
| 12 | Advances in antiretroviral therapy 显示文摘 | Temesgen Z | 2008 | Drug News Perspect2008，21，2： | 1 |
| 13 | Comparison of Some Reference Evapotranspiration Equations for California显示文摘 | Temesgen B Eching S Davidoff B | 2005 | Journal of Irrigation and Drainage Engineering2005，131，1： | 1 |
| 14 | Codominant PCR- based markers for Pinus taeda developed from mapped eDNA clones 显示文摘 | Harry D E Temesgen B Nealeb D B | 1998 | Theoretical and Applied Genetics1998，97，： | 1 |
| 15 | Seroprevalence of ovine brucel- losis in south Wollo, north eastern Ethiopia 显示文摘 | Yesuf M Alemu S Temesgen W | 2011 | East Afr J Public Health2011，8，： | 1 |
| 16 | Natural hazard as- sessment using GIS and remote sensing methods,with particular reference to the landslides in the Wondogenet Area,Ethiopia显示文摘 | Temesgen B Mohammed M U Korme T | | 0，，： | 1 |
| 17 | Generalized height-diameter models-an application for major tree species in complex stands of interior British Columbia显示文摘 | TEMESGEN H VON GADOW K | 2004 | European Journal of Forest Research2004，123，： | 1 |
| 18 | A Geometric Representation Of Turbomachinery Cascades Using Nurbs 显示文摘 | Temesgen T Mengistu Wahid S Ghaly | 2002 | AIAA2002 - 0318:1 -62002，03，： | 1 |
| 19 | Emerging concepts in disease management:a role for antimicrobial therapy in coronary artery disease显示文摘 | Girard SE Temesgen Z | 2001 | Expert Opin Pharmacother2001，2，5： | 1 |
| 20 | Natural hazard assessment using GIS and remote sensing-methods, with particular reference to the landslides in the Wondogene Area, Ethiopia显示文摘 | Temesgen B Mohammed M U | 2001 | Physics and Chemistry of the Earth Part C:Solar Terrestrial & Planetary Science2001，26，9： | 1 |
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