Papers by Zenebe Mekonnen
Most of the biomass equations were developed using sample trees collected mainly from pan-tropica... more Most of the biomass equations were developed using sample trees collected mainly from pan-tropical and tropical regions that may over- or underestimate biomass. Site-specific models would improve the accuracy of the biomass estimates and enhance the country’s MRV activities. The aim of the study is to develop site & species-specific biomass estimation models and validate and evaluate the existing generic models developed for pan-tropical forest and newly developed allometric models. Total of 150 individual sample trees was harvested from each diameter class (proportionally) for the site-specific biomass model development. Data was analyzed using SAS procedures. All relevant statistical tests (normality, multicollinearity and heteroscedasticity) were performed. Data was transformed to logarithmic functions and multiple linear regression techniques were used to develop model to estimate aboveground biomass. The root mean square error (RMSE) was used for measuring model bias, precision...
Biodiversity covers the total range of variation in and variability among systems and organisms, ... more Biodiversity covers the total range of variation in and variability among systems and organisms, at the regional, landscape, ecosystem and habitat levels, at the various organism levels, down to species, populations and individuals. Ethiopia is a country of diverse plant species forming the line share flora of 6200 species out of the total floral species of 7850 in East Africa. Of these diverse woody plants, about 12% of them are endemic. Irrespective of these truths, there is limited study on the fragmented forests and river courses in Ethiopia while vegetation resources in all areas of the country in general and in fragmented landscapes in particular , especially forests, are declining at alarming rate due to increased population followed by deforestation and land degradation. The main aim of this study was to compare the relative density, diversity and richness of woody plant species in disturbed secondary forest and river course at eastern base of Abaro Mountain at Wondo Genet. Twenty sample plots of size 10 x 10 m from each habitat type were used for vegetation inventory. It was found that the most densely populated species in the river course is Discopodium peninervum (1060 individuals/ha) and that in disturbed secondary forest is Calpurnia urea (780 individuals /ha). The Shannon Wiever Index is 2.7107 and 2.0378 for the disturbed secondary forest and river course vegetation, respectively. The Jacard’s Similarity Index between the two habitat types is 0.491. The analysis showed that the disturbed secondary forest is more diverse than the river course vegetation at the study area.
Nature-Based Solutions
Traditional agroforestry practices have economic, social, and environmental benefits to sustain h... more Traditional agroforestry practices have economic, social, and environmental benefits to sustain human and ecological systems. The demand for short-term economic benefit has derived from the traditional agroforestry practices towards monoculture cash crop production in the tropics. This study aimed to assess the greenhouse gas emission reduction capacity of traditional agroforestry systems concerning biomass and soil carbon stocks in the districts of Amhara Region, Ethiopia. From three agroforestry practices, namely, multistory, woodlots, and parkland, 300 smallholder farmers' farms were randomly selected to carry out vegetation inventory and 180 farms for litter and soil sampling. The soil samples were taken the depths 0-20 cm, 20-40 cm, and 40-60 cm. The biomass of all woody plants was estimated using already developed allometric equations. The mean total biomass carbon sink of multistory is 40.7 ton ha − 1 which was significantly (p < 0.001) higher than woodlot, 20.8 ton ha − 1 , and parkland 5.4 ton ha − 1. The mean total ecosystem (biomass plus soil) carbon of the multistory, 199.5 ton ha − 1 was significantly (p < 0.001) higher than woodlot, 134.4 ton ha − 1 , and parkland, 108.0 ton ha − 1. Soil organic carbon stocks accounted for 72-88, 83-88, and 92-98% of the total ecosystem carbon is stored in multistory, woodlot, and parkland, respectively. The study revealed that agroforestry practices could contribute to carbon sinks in the biomass and soils making it one of the nature-based solutions to climate change mitigation. This reduces greenhouse gas emissions and hence enhances the climate change mitigation and adaptation roles of the existing land uses.
Journal of Flood Risk Management, 2013
Watershed degradation has resulted in high risk of erosion followed by risk of flooding in the lo... more Watershed degradation has resulted in high risk of erosion followed by risk of flooding in the lowlands and has become the most livelihoods' threatening factor in Ethiopia in general and in the fragile watersheds of Hawassa Zuria District in particular. The objectives of this study were: (a) to assess farmers' practices of land, water and biomass management in order to improve their livelihoods; (b) to assess the existing risks and interventions and the condition of the watershed; (c) to assess the socioeconomic patterns of the farmers in the watershed. A group discussion with different stakeholders, key informant interviews and observational survey through transect walks have been used as methods of data collection. The study result has shown that the most threatening factor of degradation is gully erosion due to vegetation removal from the watershed. About 94% of the farmers used and agreed that they stabilised gullies by physical and biological measures; 60% and 88% of the respondents, respectively have indicated diversion of runoff above the gully and improvement of gully catchments as a means of gully erosion measures and reduce flooding risks in the lowlands. Community awareness creation on natural resource conservation and management as well as resolving tenure disagreements can also play role in gully control and land rehabilitation. bs_bs_banner
Forests
Despite their ecological importance, dry forests’ contribution to climate change adaptation is of... more Despite their ecological importance, dry forests’ contribution to climate change adaptation is often neglected. Hence, this study was initiated to assess the socioeconomic contribution of dry forests to climate change adaptation in Tigray Region, Ethiopia. A mixed quantitative and qualitative research design was used to examine the role of dry forests in climate change adaptation. A household questionnaire survey, key informants, and a focus group discussion were used to collect data. The results indicated that 94% of all households visited a dry forest at least once a month to access the forest and forest products. While the dry forest income level varied significantly (p < 0.05), the overall dry forest income level contributed to 16.8% of the total household income. Dry forest income enabled the reduction of the area between the line of equality and the Lorenz curve by 21% in dry evergreen Afromontane Forest users, by 3.02% in Combretum–Terminalia woodland users, and by 3% in A...
Environmental Sciences
The objective of this chapter is to review the impacts of climate change on dryland agriculture a... more The objective of this chapter is to review the impacts of climate change on dryland agriculture and its possible solutions. Climate change poses significant challenges on dryland agriculture in Ethiopia. In turn, agriculture (malpractice) has contributed to climate change by emitting GHGs such as CO2, CH4 and N2O. Globally, agriculture’s contribution takes 14% of CO2, 47% of CH4 and 84% of N2O. Agriculture contributes to 80% of total Ethiopia’s GHGs emission: CH4, N2O and CO2, respectively, contributed to 72, 15 and 14% to aggregated emission. To soothe the impacts of climate change, countries should act now differently together to stabilize the fractions of GHGs in the atmosphere at a level that would also stabilize the climate system. Adopting climate-compatible agricultural development strategies can enable to reduce agricultural GHGs emissions or sequestration enhanced while maintaining and even increasing food supply. It is understood that combating desertification, land degrad...
Ethnobotany Research and Applications, 2014
Ethiopia has an estimated one million hectares of natural bamboo forest, the largest in the Afric... more Ethiopia has an estimated one million hectares of natural bamboo forest, the largest in the African continent. Despite the versatile resource base and advanced bamboo utilization at a global scale, its great potential to enhance socioeconomic and ecological development remains unrealized in Ethiopia. More importantly, recent observations in the country showed massive bamboo flowering followed by a death that urges management interventions. The objective of this study was to examine the socioeconomic contribution of bamboo resources and typify their marketing value chain across major bamboo-growing and-marketing regions in Ethiopia, in order to promote its sustainable management. Structured questionnaires were administered to a total of 345 households to inspect the relative contribution of bamboo income to household economy. Participatory rural appraisal, key informant interviews, group discussions, market assessment, and field observations were made to understand the bamboo marketing system, actors involved, price trends, and factors affecting the bamboo value chain. Results show that crop and livestock production, forest management, and off-farm activities are major sources of income for respondent households. Fifty-three percent of the respondents reported bamboo income. Though it significantly varies across the study localities (p < 0.005), bamboo income contributed up to 11% of the annual cash income of the households, the lowest (3.4%) at Masha and the largest (38%) at Banja and Bahir Dar Zuria Districts. Positive and significant correlation was observed among cash incomes from bamboo, crop, petty trade, and other Non-Timber Forest Products (NTFPs). Producer farmers, village level traders, town and city wholesalers, small-and medium-scale bamboo processing and marketing firms, and town and city consumers are identified as major actors in the bamboo value chain. Fifty-five percent of the respondents indicated presence of poor horizontal and vertical
Ethnobotany Research and Applications, Dec 1, 2013
Forests, Trees and Livelihoods, 2007
Abstract The growing demand for construction and fuel wood and the wide adaptation of Eucalyptus ... more Abstract The growing demand for construction and fuel wood and the wide adaptation of Eucalyptus to the different agro-ecological zones of the country are resulting in increased plantation of Eucalyptus by smallholders, but the policy environment in Ethiopia ...
... with a considerable positive net present value, compared to the alternative agricultural crop... more ... with a considerable positive net present value, compared to the alternative agricultural crops (Tesfaye 1997, Daba ... farm implements plus an enhancing effect on environment (Amanuel 1996, Daba 1998, FAO 1988, Solomon 1999, Jagger ... 2002 ; Eshetu 2002 ; Mulugeta 2004 ...
Advances in Climate Change Research
Climate change/variability and environmental degradation have increased in the central rift valle... more Climate change/variability and environmental degradation have increased in the central rift valley of Ethiopia, which in turn making the people inhabiting in that ecosystem more vulnerable to the impacts. The purposes of this study were to assess the vulnerability of households and agro-ecosystems to climate change and environmental degradation and the factors determining vulnerabilities in the central rift valley, Ethiopia. Data were collected between November 2014 and May 2015 by interviewing 355 respondents. This has been supplemented with focus group discussions and key informant interviews. The indicator and matrix methods were used to describe socio-ecological vulnerabilities. The results showed that about 9% of the respondents were highly vulnerable to climate change/variability, and environmental degradation. Households in the lowland have the largest proportion of high vulnerable households (60%), while households in highland have the largest proportion of low vulnerable households (30%). In the lowland agro-ecology, the adaptive capacity component has contributed the largest share to household's vulnerability index to the impacts of climate change/variability and environmental degradation. The sensitivity component has higer contribution in highland agro-ecology and the exposure component in the midland agro-ecology. There were variations of income deviation between agro-ecologies that lead to variation in vulnerability of households. Household vulnerability index has shown a very light negative correlation with livelihood diversification index. The poorest households with little share of the total income distribution and with low livelihood diversity index, were the most vulnerable. The results showed that the highest exposure index on ecosystem functions and agricultural performance were in the lowland agro-ecology. This study highlighted the need to assess the social and ecological vulnerabilities in integrated approach as singling out one from the other is difficult. That is, social vulnerability impacts ecological vulnerability and vice versa.
was found in the amount collected and income generated per household and locality. Strong correla... more was found in the amount collected and income generated per household and locality. Strong correlation was observed between cash income from gums and resins and off-farm activities (R = 0.74) and other types of non-timber forest products like honey (R = 0.72, α = 0.01). However, weak correlation was observed between incomes from gums and resins and crop and livestock production. Despite the observed inefficient value chain, the gum and resin resources have considerable contributions to the national economy. For instance, the annual average revenue from three districts in Tigray National Regional State was USD 882,000 in 2010. Between 2002 and 2010, about 2,306 tonnes of different gums and resins were traded and average revenue of USD 3,220,542 was obtained in one district in the same region. At the national level, between 1997 and 2010 about 6,174 tonnes of gum arabic and about 33,865 tonnes of other gums and resins were exported, and more than USD 72 million were gen
Energy Sources Part A-recovery Utilization and Environmental Effects, 2020
Although biomass fuel is principally traditional, it remains the major source of household energy... more Although biomass fuel is principally traditional, it remains the major source of household energy and needs critical consideration in its development. Due to population growth and the consequence o...
The fast growth rate of Eucalyptus to provide possible products for the livelihood consumption an... more The fast growth rate of Eucalyptus to provide possible products for the livelihood consumption and for the market has over won the continuing planting of the species irrespective of the policy resistant from the policy makers in Ethiopia. Until the end of the 1990s, the main tree seedling produced in government nurseries was Eucalyptus, but starting from the early 2000s, production of Eucalyptus in government nurseries has been given up. On the contrary, Eucalyptus gives some attention for concern in the context of diversified plantations by smallholder farmers, because owing to its importance to the household livelihood strategy by providing income and wood products for household consumption. With a large proportion of the world population in general, and of developing countries such as Ethiopia in particular, depending on wood for cooking and heating, the economic importance of Eucalyptus is immense. Eucalyptus outputs have significant impacts of change on rural livelihoods. The o...
Accurate information on land use and land cover change (LULCC) is critical for understanding the ... more Accurate information on land use and land cover change (LULCC) is critical for understanding the causes of change and for developing effective policies and strategies to slow and reverse land degradation. In Ethiopia, the speed and scale of LULCC has been accelerated in the last 3-4 decades of the 21 st century. The objectives of this study were to assess: (i) the extent of LULCC and normalized difference vegetation index (NDVI) and the link to land degradation; (ii) the causes of LULCC and implication for climate change adaptation. Satellite images analysis was used to detect the change in area and vegetation index, and farmers’ perception to see the magnitude of LULCC dynamics and causes of deforestation. Correlations were made between vegetation index with dry season rainfall and temperature. The analysis of confusion matrix of LULC classification showed 87% accuracy with Kappa coefficient of 0.84. In the period 1986-2016, agriculture and settlement areas have increased by 250% a...
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Papers by Zenebe Mekonnen