Ethiopia has a mountainous landscape which can be divided into the Northwestern and Southeastern plateaus by the Main Ethiopian Rift and Afar Depression. Debre Sina area is located in Central Ethiopia along the escarp...Ethiopia has a mountainous landscape which can be divided into the Northwestern and Southeastern plateaus by the Main Ethiopian Rift and Afar Depression. Debre Sina area is located in Central Ethiopia along the escarpment where landslide problem is frequent due to steep slope, complex geology, rift tectonics, heavy rainfall and seismicity. In order to tackle this problem, preparing a landslide susceptibility map is very important. For this, GISbased frequency ratio(FR) and logistic regression(LR) models have been applied using landslide inventory and the nine landslide factors(i.e. lithology, land use, distance from river & fault, slope, aspect, elevation, curvature and annual rainfall). Database construction, weighting each factor classes or factors, preparing susceptibility map and validation were the major steps to be undertaken. Both models require a rasterized landslide inventory and landslide factor maps. The former was classified into training and validation landslides. Using FR model, weights for each factor classes were calculated and assigned so that all the weighted factor maps can be added to produce a landslide susceptibility map. In the case of LR model, the entire study area is firstly divided into landslide and non-landslide areas using the training landslides. Then, these areas are changed into landslide and non-landslide points so as to extract the FR maps of the nine landslide factors. Then a linear relationship is established between training landslides and landslide factors in SPSS. Based on this relationship, the final landslide susceptibility map is prepared using LR equation. The success-rate and prediction-rate of FR model were 74.8% and 73.5%, while in case of LR model these were 75.7% and 74.5% respectively. A close similarity in the prediction and validation rates showed that the model is acceptable. Accuracy of LR model is slightly better in predicting the landslide susceptibility of the area compared to FR model.展开更多
Dry afromontane forests are among the most poorly managed and endangered ecosystems.Therefore,we assessed the composition,diversity,and conservation status of woody plant species of the Debre Libanos church forests an...Dry afromontane forests are among the most poorly managed and endangered ecosystems.Therefore,we assessed the composition,diversity,and conservation status of woody plant species of the Debre Libanos church forests and surrounding forest lands in Oromiya Regional National State,central Ethiopia in 62 nested circular sample plots spaced 200 m apart along two transect lines.Large circular plots 314 m^(2)were used to sample trees with DBH of at least 10 cm,and subplots of 28.26 m^(2)were laid in each main plot were used to assess saplings and shrubs;a small subplot of 3.14 m2 was used to assess seedlings.In total,70 woody plant species belonging to 62 genera and 43 families were recorded.Of these,59,28 and 32 were in the church,government and private forest types,respectively.The most dominant families were Fabaceae and Verbenaceae,each represented by five species.In the forests considered,trees accounted for 61%,and shrubs with diameter at breast height(DBH)of 1-10 cm accounted for ca.33%.Among growth forms of woody species,shrubs and seedlings,followed by trees constituted much of the density of woody species in all the three ownership types of forests.The church forest had the most species(59)and highest Shannon(3.12)and Simpson(0.92)species diversity indices,and the government and private forests had a nearly similar total number of species and Shannon and Simpson species diversity indices.Most of the species with higher importance value indices(IVI)were indigenous in origin within the church forest(Juniperus procera=82),government forest(J.procera=66)and private forest(Acacia abyssinica=84).The composition,diversity,and population structure of woody species in the church forest were significantly higher than in the other forest lands.However,interventions of the government and private sectors to conserve forest systems in the areas,particularly the government-owned forest and specific species such as Olea europaea need active enrichment plantings due to their limited natural regeneration.Without improved management interventions,livelihood income diversification and ecosystem services obtained from the forest will not be sustainable.展开更多
The importance of accurate and timely information describing the nature and extent of land resources and changes over time is increasing, especially in fast-growing urban areas. We have developed a methodology to dete...The importance of accurate and timely information describing the nature and extent of land resources and changes over time is increasing, especially in fast-growing urban areas. We have developed a methodology to detect changes in land cover using satellite images for the years 1997, 2002, 2012 and 2017. The categories of five-class classification in the study area were built up area, plantation, waterbody, agricultural land and pastureland. The maps showed that between 1997 and 2017, the amount of urban or developed land increased from 8.12% to 52.4% of the total area, while agriculture land, plantation, waterbody and pastureland decreased from the 91.88% to 47.6% from the entire study area. The results showed that the urban (highly built-up) area increased dramatically. Inversely, pastureland, agricultural land, waterbody, and plantation decreased obviously from the period of 1997 to 2017. The remote sensing and GIS technique used in this study proved to be efficient;the time was shortened for the analysis of the city extension;and it was discovered that it was a useful tool to evaluate the effects of urbanization on the basis of the satellite image of the given years. The results quantify land use, coverage change patterns in Debre Tabor Town and demonstrate the potential of remote sensing, and GIS tools provide an accurate and cost-effective means to track land cover changes along time that can be used as management decisions and guidelines.展开更多
Background:Data regarding tuberculosis(TB)treatment outcomes,proportion of TB/HIV co-infection and associated factors have been released at different TB treatment facilities in Ethiopia and elsewhere in the world as p...Background:Data regarding tuberculosis(TB)treatment outcomes,proportion of TB/HIV co-infection and associated factors have been released at different TB treatment facilities in Ethiopia and elsewhere in the world as part of the auditing and surveillance service.However,these data are missing for the TB clinic offering directly observed treatment short-course(DOTs)at Debre Tabor General Hospital(DTGH).Methods:The authors analysed the records of 985 TB patients registered at the DTGH from September 2008 to December 2016.Data on patients’sex,age,type of TB,and treatment outcomes were extracted from the TB treatment registration logbook.The treatment outcome of patients was categorized according to the National TB and Leprosy Control Program guidelines:cured,treatment completed,treatment failed,died,and not evaluated(transferred out and unknown cases).Results:Around half of the registered patients were males(516,52.4%).In terms of TB types,381(38.7%),241(24.5%),and 363(36.9%)patients had smear-negative pulmonary TB,smear-positive pulmonary TB,and extra pulmonary TB,respectively.Six hundred and seventy-two patients(90.1%)had successful treatment outcomes(cured and treatment completed),while 74 patients(9.9%)had unsuccessful treatment outcomes(death and treatment failure).TB treatment outcome was not associated with age,sex,type and history of TB,or co-infection with HIV(P>0.05).The proportion of TB/HIV co-infection was at 24.2%,and these were found to be significantly associated with the age groups of 25-34,35-44 and≥65 years:(aOR:0.44;95%CI:0.25-0.8),(aOR:0.39;95%CI:0.20-0.70),(aOR:4.2;95%CI:1.30-12.9),respectively.Conclusions:The proportion of patients with successful treatment outcomes was above the World Health Organization target set for Millennium Development Goal of 85%and in line with that of the global milestone target set at>90%for 2025.Relatively higher proportions of transfer-out cases were recorded in the present study.Similarly,the proportion of TB/HIV co-infection cases was much higher than the national average of 8%.Thus,the health facility under study should develop strategies to record the final treatment outcome of transfer-out cases.In addition,strategies to reduce the burden of TB/HIV co-infection should be strengthened.展开更多
20152023 Cai Baoxin(Yunnan Institute of Geological Environmental Monitoring,Kunming650216,China);Huang Yu An Analysis of Differences in Accumulation of Heavy Metals in Main Crops in a Tin Mining Area of Yunnan Provinc...20152023 Cai Baoxin(Yunnan Institute of Geological Environmental Monitoring,Kunming650216,China);Huang Yu An Analysis of Differences in Accumulation of Heavy Metals in Main Crops in a Tin Mining Area of Yunnan Province(Geological Bulletin of China,展开更多
文摘Ethiopia has a mountainous landscape which can be divided into the Northwestern and Southeastern plateaus by the Main Ethiopian Rift and Afar Depression. Debre Sina area is located in Central Ethiopia along the escarpment where landslide problem is frequent due to steep slope, complex geology, rift tectonics, heavy rainfall and seismicity. In order to tackle this problem, preparing a landslide susceptibility map is very important. For this, GISbased frequency ratio(FR) and logistic regression(LR) models have been applied using landslide inventory and the nine landslide factors(i.e. lithology, land use, distance from river & fault, slope, aspect, elevation, curvature and annual rainfall). Database construction, weighting each factor classes or factors, preparing susceptibility map and validation were the major steps to be undertaken. Both models require a rasterized landslide inventory and landslide factor maps. The former was classified into training and validation landslides. Using FR model, weights for each factor classes were calculated and assigned so that all the weighted factor maps can be added to produce a landslide susceptibility map. In the case of LR model, the entire study area is firstly divided into landslide and non-landslide areas using the training landslides. Then, these areas are changed into landslide and non-landslide points so as to extract the FR maps of the nine landslide factors. Then a linear relationship is established between training landslides and landslide factors in SPSS. Based on this relationship, the final landslide susceptibility map is prepared using LR equation. The success-rate and prediction-rate of FR model were 74.8% and 73.5%, while in case of LR model these were 75.7% and 74.5% respectively. A close similarity in the prediction and validation rates showed that the model is acceptable. Accuracy of LR model is slightly better in predicting the landslide susceptibility of the area compared to FR model.
基金supported financially by the Fundamental Research Funds of Environment and Coffee Forest Forum。
文摘Dry afromontane forests are among the most poorly managed and endangered ecosystems.Therefore,we assessed the composition,diversity,and conservation status of woody plant species of the Debre Libanos church forests and surrounding forest lands in Oromiya Regional National State,central Ethiopia in 62 nested circular sample plots spaced 200 m apart along two transect lines.Large circular plots 314 m^(2)were used to sample trees with DBH of at least 10 cm,and subplots of 28.26 m^(2)were laid in each main plot were used to assess saplings and shrubs;a small subplot of 3.14 m2 was used to assess seedlings.In total,70 woody plant species belonging to 62 genera and 43 families were recorded.Of these,59,28 and 32 were in the church,government and private forest types,respectively.The most dominant families were Fabaceae and Verbenaceae,each represented by five species.In the forests considered,trees accounted for 61%,and shrubs with diameter at breast height(DBH)of 1-10 cm accounted for ca.33%.Among growth forms of woody species,shrubs and seedlings,followed by trees constituted much of the density of woody species in all the three ownership types of forests.The church forest had the most species(59)and highest Shannon(3.12)and Simpson(0.92)species diversity indices,and the government and private forests had a nearly similar total number of species and Shannon and Simpson species diversity indices.Most of the species with higher importance value indices(IVI)were indigenous in origin within the church forest(Juniperus procera=82),government forest(J.procera=66)and private forest(Acacia abyssinica=84).The composition,diversity,and population structure of woody species in the church forest were significantly higher than in the other forest lands.However,interventions of the government and private sectors to conserve forest systems in the areas,particularly the government-owned forest and specific species such as Olea europaea need active enrichment plantings due to their limited natural regeneration.Without improved management interventions,livelihood income diversification and ecosystem services obtained from the forest will not be sustainable.
文摘The importance of accurate and timely information describing the nature and extent of land resources and changes over time is increasing, especially in fast-growing urban areas. We have developed a methodology to detect changes in land cover using satellite images for the years 1997, 2002, 2012 and 2017. The categories of five-class classification in the study area were built up area, plantation, waterbody, agricultural land and pastureland. The maps showed that between 1997 and 2017, the amount of urban or developed land increased from 8.12% to 52.4% of the total area, while agriculture land, plantation, waterbody and pastureland decreased from the 91.88% to 47.6% from the entire study area. The results showed that the urban (highly built-up) area increased dramatically. Inversely, pastureland, agricultural land, waterbody, and plantation decreased obviously from the period of 1997 to 2017. The remote sensing and GIS technique used in this study proved to be efficient;the time was shortened for the analysis of the city extension;and it was discovered that it was a useful tool to evaluate the effects of urbanization on the basis of the satellite image of the given years. The results quantify land use, coverage change patterns in Debre Tabor Town and demonstrate the potential of remote sensing, and GIS tools provide an accurate and cost-effective means to track land cover changes along time that can be used as management decisions and guidelines.
基金This research did not receive any funding from any organization.
文摘Background:Data regarding tuberculosis(TB)treatment outcomes,proportion of TB/HIV co-infection and associated factors have been released at different TB treatment facilities in Ethiopia and elsewhere in the world as part of the auditing and surveillance service.However,these data are missing for the TB clinic offering directly observed treatment short-course(DOTs)at Debre Tabor General Hospital(DTGH).Methods:The authors analysed the records of 985 TB patients registered at the DTGH from September 2008 to December 2016.Data on patients’sex,age,type of TB,and treatment outcomes were extracted from the TB treatment registration logbook.The treatment outcome of patients was categorized according to the National TB and Leprosy Control Program guidelines:cured,treatment completed,treatment failed,died,and not evaluated(transferred out and unknown cases).Results:Around half of the registered patients were males(516,52.4%).In terms of TB types,381(38.7%),241(24.5%),and 363(36.9%)patients had smear-negative pulmonary TB,smear-positive pulmonary TB,and extra pulmonary TB,respectively.Six hundred and seventy-two patients(90.1%)had successful treatment outcomes(cured and treatment completed),while 74 patients(9.9%)had unsuccessful treatment outcomes(death and treatment failure).TB treatment outcome was not associated with age,sex,type and history of TB,or co-infection with HIV(P>0.05).The proportion of TB/HIV co-infection was at 24.2%,and these were found to be significantly associated with the age groups of 25-34,35-44 and≥65 years:(aOR:0.44;95%CI:0.25-0.8),(aOR:0.39;95%CI:0.20-0.70),(aOR:4.2;95%CI:1.30-12.9),respectively.Conclusions:The proportion of patients with successful treatment outcomes was above the World Health Organization target set for Millennium Development Goal of 85%and in line with that of the global milestone target set at>90%for 2025.Relatively higher proportions of transfer-out cases were recorded in the present study.Similarly,the proportion of TB/HIV co-infection cases was much higher than the national average of 8%.Thus,the health facility under study should develop strategies to record the final treatment outcome of transfer-out cases.In addition,strategies to reduce the burden of TB/HIV co-infection should be strengthened.
文摘20152023 Cai Baoxin(Yunnan Institute of Geological Environmental Monitoring,Kunming650216,China);Huang Yu An Analysis of Differences in Accumulation of Heavy Metals in Main Crops in a Tin Mining Area of Yunnan Province(Geological Bulletin of China,
