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| 1 | Effects of grazing intensity to water source on grassland condition, yield and nutritional content of selected grass species in Northwest Ethiopia显示文摘Background:Savanna grasslands are globally important ecosystems consisting of one of the most extensive grazing lands with unique biodiversity.The objectives of the study were to assess the effect of grazing intensity on grassland ecosystem condition,herbaceous plant biomass production,and nutritional content of selected grass species.Methods:The study was conducted at Chagni Ranch,Northwest Ethiopia.Four transects to water source point at regular intervals of 20m between sampling plots along transects were used for data collection.The distance between the four transects was 200m in radius.Data were collected on grass composition,basal cover,litter cover,number of seedlings,and age distribution of dominant grasses(i.e.,young,medium,or old in terms of stage of maturity),soil condition in terms of soil compaction,and soil erosion linked to the effects of trampling by grazing animals along transects(hereafter referred to as transect)to water source point.The total sample size for grass species was 160 plots.The grassland ecosystem condition,herbaceous biomass,and grass nutritional content were used as response variables linked to transect from water source point.The effects of transect on grassland ecosystem condition scores and grass nutritional content were analyzed using the analysis of variance(ANOVA).Results:Grassland condition factors like grass composition,basal cover,litter cover,age distribution of dominant grasses,and soil condition were significantly(P<0.05)higher for the furthest transect to water source point than nearest transect.Out of the 28 identified herbaceous species,grasses accounted for 64.3%of the herbaceous community.Within grass species,about 55.6%were highly desirable in terms of palatability and grazing value(as most palatable species are susceptible to heavy grazing intensity).The results showed a significantly(P<0.05)higher proportion of perennial grasses at the furthest transect to water source point than nearest transect.The dry matter yield at the furthest transect(TD4)and third transect(TD3)were significantly(P<0.05)higher than the nearest transect to water source point(i.e.,the first transect(TD1)and second transect(TD2)).Ash,neutral detergent fiber,acid detergent fiber,and acid detergent lignin contents of Cynodon dactylon,Sporobolus pyramidalis,and Digitaria ternata were significantly(P<0.05)higher at the furthest transect to water source point than nearest transect.Grazing intensity had no significant effect on the crude protein content of Cynodon dactylon and Sporobolus pyramidalis at different transects.Conclusions:The results showed that the furthest transect to water source point were in good condition.Grass biomass production and the nutritional contents of grasses were higher for the furthest transect to water source point.The results suggested that increased grazing intensity towards water source point greatly reduced the abundance of desirable perennial grasses and the sustainability of grassland for livestock production. | Yaregal Melak Ayana Angassa Aster Abebe | 2019 | Ecological Processes2019，8，1： | 3 |
| 2 | Community-based knowledge towards rangeland condition, climate change, and adaptation strategies: the case of Afar pastoralists显示文摘Introduction:Pastoral communities have a comprehensive knowledge of their environments.This knowledge was acquired through extensive observation of the local environment and continuous herding practices.Pastoralists’wisdom about their local environment and adaptation strategies to climate change is essential for sustainable development.Thus,appreciation of pastoralists’knowledge about their environment is also important for the integration of indigenous knowledge with the proper application of scientific approach to fit with the prevailing ecological potential of pastoral areas.Methods:Data were collected using focus group discussions,key informant interviews,and in-depth interviews.The in-depth interviews were conducted using a semi-structured questionnaire that was administered to 100 household heads with the age of above 50 years old.Respondents were randomly drawn from selected Pastoralists Associations(PAs)of two study districts.Data were analyzed using descriptive statistics as well as the logit model.The logit model was used to analyze the different coping strategies of pastoralists to overcome the failure of rain during different seasons.This was done by complementing pastoralists’indigenous knowledge of time-series-based analysis across four seasons(Kerma,Gillal,Hagay,and Sugum)vs.the existing meteorological records.Forty years(from 1971 to 2011)of existing metrological data were used to compare the empirical evidence with pastoralists’perceptions.Results:Respondents mentioned that livestock number was the best indicator for evaluating rangeland condition in Afar region.The existing empirical evidence based on metrological data did not show any significant decline in precipitation for the last four decades between 1971 and 2011 as opposed to the perception of pastoralists where 80%of them reported a decline in precipitation.A one unit increase in labor force suggested about 16.1%decrease in the choice of livestock selling as coping strategy in Afar pastoral areas of North-East of Ethiopia.The non-intervened pastoral households had more preference(3.78%)to practice herd splitting than those pastoral households in the intervened district.Similarly,the non-intervened pastoral households had 4.43%more preference to use crop residue for livestock feeding than pastoral HHs in the intervened areas.Conclusions:Communities’perceptions showed that livestock number was the best indicator of rangeland condition in the study area.Afar pastoralists’observations with regard to temperature and precipitation trends over the last four decades greatly corresponded with the existing metrological-based empirical evidence.However,pastoralists’perception in terms of reduced precipitation was not confirmed by the meteorological-based data records for the short rainy season(SRS).Afar pastoralists’experience showed that the short rainy season was the best indicator for the occurrence of droughts as compared to other seasons in Afar.Our results suggest that most coping strategies are labor force demanding,and the situation worsens during the long rainy season(LRS).We suggest that differences in intervention between the study areas should not be overlooked as a policy tool in tackling the impact of climate change. | Minyahel Tilahun Ayana Angassa Aster Abebe | 2017 | Ecological Processes2017，6，1： | 2 |
| 3 | Perception and attitude of pastoralists on the use and conservation of rangeland resources in Afar Region,Ethiopia显示文摘Introduction:Community perception plays a significant role in rangeland resource management.Traditional rangeland management practices by the pastoral communities are based on accumulated knowledge in connection to their local environment.Pastoralism played a vital role in food production and sustaining its inhabitants in arid environment for millennia.However,national policies and development interventions in East African pastoral systems have often overlooked pastoralism while centered on the modernization of agricultural sector for economic development and poverty reduction.Methods:We used household survey,focus group discussion,key informant interview,and individual questionnaire to understand the perceptions and attitude of Afar pastoralists towards rangeland resource use and conservation practices,as well as impacts of development intervention on traditional rangeland resource use and conservation practices.The data were analyzed using index ranking and descriptive statistics.Results:The results showed that livestock holding per household was higher on average(22.90±2.27 Tropical Livestock Unit(TLU))in the non-intervened woreda than in the intervened woreda(8.30±3.85 TLU).Respondents mentioned that livestock productivity was adversely affected by a number of factors such as invasion of Prosopis juliflora(Dergi Hara),shrinkage in the capacity of rangelands(Beadu and Bebea’),and recurrent droughts.Scarcity of grazing resources attributed to the invasion of Dergi Hara and drought created livestock feed crisis with strong implication on the livelihood of pastoralists.Our results showed that the traditional resource management practices such as mobility,herd splitting,and diversification had a role to contribute to the improvement of rangeland management and conservation of biodiversity.Traditional rules and seasonal-based grazing patterns of riversides during drought were perceived as key elements for rangeland resource management and conservation of rangeland resources in the study area.Conclusions:Communities’perception showed that the traditional practices of rangeland management systems are effective and environmentally sustainable.In contrast,inappropriate development interventions put rangelands under severe pressure.Although development interventions were aimed at improving the condition of Afar rangeland,they could not bring any enduring solution in terms of improvement of rangeland resources. | Minyahel Tilahun Ayana Angassa Aster Abebe Alemayehu Mengistu | 2016 | Ecological Processes2016，5，1： | 2 |
| 4 | Immune thrombocytopenia caused by glycoprotein II b/ Ilia inhibitors 显示文摘 | Aster RH | 2005 | Chest2005，127，2： | 1 |
| 5 | Human Platelet anti- gen-specific alloantibodies implicatedinll cases 1162 cases of neo- natal alloimmune thrornbocytopenia 显示文摘 | Davoren A Curtis BR Aster RH | 2004 | Transfusion2004，44，8： | 1 |
| 6 | Incidence of the Nak( a)-negative platelet phenotype in African Americans is similar to that of Asians 显示文摘 | Curtis BR Aster RH | 1996 | Transfusion1996，36，4： | 1 |
| 7 | The multifaceted role of Notch in cancer显示文摘 | Roy M Pear WS Aster JC | 2007 | Curr Opin Genet Dev2007，17，1： | 1 |
| 8 | Analytical fractionation of aquatic humic substances and their metal species by means of muhistage uhrafihration 显示文摘 | Aster B Burba P Broekaert J A C A C | 1996 | Fresenius'' Journa| of Analytical Chemistry1996，354，56： | 1 |
| 9 | FGFR1 is fused with a novel zinc-finger gene,ZNF198,in the t (8;13) leukaemia/lymphoma syndrome显示文摘 | Xiao S Nalabolu SR Aster JC | | 0，，01： | 1 |
| 10 | Immune thrombocytopenia associated with tuberculosis显示文摘 | Jurak SS Aster R Sawaf H | 1983 | Clin Pediatr (Phila)1983，22，4： | 1 |
| 11 | Canonical Notch Signaling Is Dispensable for the Maintenance of Adult Hematopoietic Stem Cells显示文摘 | Ivan Maillard Ute Koch Alexis Dumortier Olga Shestova Lanwei Xu Hong Sai Seth E. Pross Jon C. Aster Avinash Bhandoola Freddy Radtke Warren S. Pear | 2008 | Cell Stem Cell2008，，4： | 1 |
| 12 | Drug -induced thrombocytopenia : pathogenesis, evaluation, and management显示文摘 | GEORGE JN ASTER RH | 2009 | Hematolo- gy Am SocHematol Educ Program2009，2009，1： | 1 |
| 13 | Improving the specificity of the PF4 ELISA in diagnosing heparin-induced thrombocytopenia显示文摘 | McFarland J Lochowicz A Aster R | 2012 | Am J Hematol2012，87，8： | 1 |
| 14 | Development and testing of the oncology patients, perceptions of the quality of nursing care scale 显示文摘 | Radwin L Aster K Rubin K | 2003 | Oncol Nurs Forum2003，30，2： | 1 |
| 15 | Canonical Notch Signaling Is Dispensable for the Maintenance of Adult Hematopoietic Stem Cells显示文摘 | Ivan Maillard Ute Koch Alexis Dumortier Olga Shestova Lanwei Xu Hong Sai Seth E. Pross Jon C. Aster Avinash Bhandoola Freddy Radtke Warren S. Pear | 2008 | Cell Stem Cell2008，，4： | 1 |
| 16 | Drug-induced immune thrombocytopenia显示文摘 | Aster RH Bougie DW | 2007 | N Engl J Med2007，357，6： | 1 |
| 17 | Molecular biology of Burkitt's lymphoma显示文摘 | Hecht J Aster J | 2000 | J Clin Oncol2000，18，12： | 1 |
| 18 | Structural requirements for assembly of the CSL, intracellular Notchl, mas- termind like transcriptional activation complex显示文摘 | Nam Y Weng AP Aster JC | 2003 | J Biol Chem2003，278，21： | 1 |
| 19 | Structural requirements for assembly of the CSL, intracellular Notch 1, mastermind like 1 transcriptional activation complex显示文摘 | Nam Y Weng AP Aster JC | 2003 | J Biol Chem2003，278，21： | 1 |
| 20 | Acute hemorrhagic leukoencephalitis:a critical entity for forensic pathologists to recognize显示文摘 | Lann MA Lovell MA Kleinschmidt-DeM asters BK | 2010 | Am J Forensic Med Pathol2010，31，1： | 1 |
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