Online Session 1 :
Africa Oriented Research Topic
The Impact of Soil and Water Conservation on Plant Diversity and Ecosystem Restoration in Tigray, Ethiopia
Abstract
Land degradation, primarily driven by soil erosion and deforestation, threatens biodiversity and disrupts essential ecosystem services, which are integral to both environmental and human well-being. Biophysical soil and water conservation (SWC) practices are crucial for restoring ecosystems, yet their effects on plant species diversity and community composition, especially in hilly landscapes, are still under-explored. This study explores how integrated biophysical SWC measures can promote environmental co-existence and co-prosperity by restoring biodiversity and ecosystem functions. It assesses the impact of SWC on plant species composition, diversity, and regeneration at the watershed level, offering vital insights for developing sustainable and equitable conservation strategies. Vegetation and soil samples were collected from treated and untreated sub-watersheds to analyze species diversity, composition, and regeneration along slope gradients. The results reveal that conservation efforts significantly enhance plant diversity, with treated areas supporting a higher number of species and superior diversity indices compared to untreated areas. The conserved land demonstrated greater species density, particularly on lower slopes, and improved regeneration, with 50% of species showing fair to good regeneration. Ordination analysis using Principal Component Analysis (PCA) showed strong correlations between species composition and soil properties, particularly organic matter, pH, and moisture content. These findings underscore the crucial role of biophysical SWC in fostering biodiversity, species regeneration, and ecosystem resilience, directly contributing to the goals of environmental sustainability and community prosperity. By improving soil quality and plant diversity, these conservation practices support both ecological balance and the livelihoods of local communities, aligning with the principles of co-existence, co-prosperity, and co-righteousness. Expanding and monitoring these conservation measures is essential for ensuring long-term ecological and socio-economic benefits in hilly landscapes, thus promoting ethical and sustainable land management practices.
Keywords: Conservation effectiveness, ecosystem restoration, herbaceous species, importance value index, species diversity, vegetation dynamics, vegetation sampling, woody species.
Impact evaluation of stone bund effectiveness on selected soil properties and wheat yield in rain-fed croplands of the Tigray highlands, northern
Ethiopia
Abstract
Soil and water conservation (SWC) measures are critical for enhancing agricultural yield and environmental sustainability, especially in the rain-fed croplands of Tigray, Northern Ethiopia, where land degradation is a growing concern. Though, the key factors that prevent farmers from adopting these SWC interventions at the household level have not yet been investigated in detail. Thus, this study examines the factors influencing the adoption of SWC practices by farmers on rain-fed croplands in the highlands of northern Ethiopia. Data were gathered from 335 farmers through a household survey using a multi-stage sampling method. The study used a multivariate probit (MVP) model to investigate the impact of socioeconomic and institutional factors and physical characteristics on the adoption decisions for different SWC measures (stone bund, stone-faced soil bund, and soil bund) at the household level. The findings display factors such as age, education, income, slope, credit, livestock unit, number of contacts and plots, plot distance, tenure, and collective action significantly influence the implementation of these conservation practices. Additionally, the adoption of the three SWC measures was statistically significant and was found to be interrelated, implying that the adoption of stone bunds increases the likelihood of adopting stone-faced soil bunds and soil bunds (implying complementarity). However, there was a negative correlation between stone-faced soil bunds and soil bunds. These findings underscore the need for integrated policies that promote education, credit, improved contacts, and secure land tenure and also highlight the importance of collective action to control soil erosion, adopting improved livestock management, and addressing physical barriers in increasing adoption rates in the region.
Keywords: Soil degradation, Adoption decisions, Multiple soil water conservation measures, Multivariate probit model, Northern Ethiopia
Tree Height Estimation from Unmanned Aerial Vehicle Imagery and Its Sensitivity on Above Ground Biomass Estimation in Dry Afromontane Forest, Northern Ethiopia
Abstract
Tree height is a parameter useful for calculating above-ground forest biomass and is mostly measured traditionally by ground survey. On the other hand, measuring the forest tree height and biomass estimation through field survey is labor-intensive and time-consuming. The application of remote sensing for forest above-ground biomass (AGB) estimation without forest destruction is important in order to estimate the carbon sequestration potential of the forest. The unmanned aerial vehicle (UAV) is an elating technology, which can help to estimate tree height and it is evolving at a rapid speed. Moreover, assessing the relationship between estimated and measured tree height is necessary for the future application of estimated tree height on AGB estimation. However, tree height estimation from photogrammetric UAV imagery in the dry Afromontane Forest and its sensitivity to AGB estimation are not investigated. Thus, this study aimed to assess the accuracy of tree height estimated from photogrammetric UAV imagery and the sensitivity of the estimated tree height on AGB estimation. Photogrammetric UAV acquired images and sample trees height measured on the ground were collected in Desa’a dry Afromontane Forest, Northern Ethiopia. Tree height was estimated from photogrammetric UAV acquired images and compared with tree heights measured on the ground. Moreover, the sensitivity of the estimated tree height on AGB estimation was investigated. The estimated tree height explained 89% of the tree height measured in the field. A considerable difference between estimated and measured tree height has an insignificant effect on AGB estimation. Thus, in the dry land Afromontane Forest the application of UAV aerial imagery for tree height estimation is promising to estimate AGB.
Developing monitoring framework for the sustainability of area Exclosure: Lessons from the best practices in Tigray
Abstract
Ethiopia faced a prolonged loss in its forest resources due to persistent degradation. The principal factors contributing to the nation’s diminishing forest resources are believed to be overgrazing and deforestation resulting from forest removal for agricultural purpose. The situation in Tigray, a region of Ethiopia, is more dire than those in other areas of the country. To combat this degradation process, the government has put in place a number of measures, such as area exclosure, which keeps people and animals from disturbing the damaged areas. Among other aspects of the degraded areas, the technique has greatly increased plant diversity and soil fertility. But it has also been hindered by many causes, such as difficulties with benefit sharing and competition for livestock feed. These kinds of difficulties caused the practice to become unsustainable. An alternative strategy must be looked for in order to tackle these challenges and ensure the practice’s sustainability. In addition to carefully examining the best practices for exclosure, this paper presents an alternative that might promote the sustainability of area exclosures Therefore, monitoring framework which integrates conservation and utilization is believed to be a solution to the challenges
Keywords: Area exclosure, land degradation, sustainability, restoration
Historical Climate Variability and Growing Season Dynamics in Ethiopia's Central Rift Valley
Abstract
Climate change and variability pose serious challenges worldwide, with significant local impacts on agriculture and livelihoods. Although many studies have addressed these issues at national or regional levels, local-scale characterization remains essential for effective adaptation. This study investigates the historical climate variability in Melkassa and Negele Arsi, two key areas in Ethiopia’s Central Rift Valley, to inform climate-resilient agricultural planning. The mean annual rainfall was 840.73 mm at Melkassa and 869.35 mm at Negele Arsi, with corresponding standard deviations of 149.01 mm and 70.3 mm. Rainfall in the area follows a bimodal pattern, with the Belg season (March–May) receiving 175–358 mm and the Kiremt season (June–September) receiving 420–680 mm. The mean onset of the main rainy season occurred on June 27 at Melkassa and June 24 at Negele Arsi. The onset dates were highly variable, with coefficients of variation (CV) of 38.7% at Melkassa and 63.2% at Negele Arsi. The earliest onset was observed on June 5 at Melkassa and June 3 at Negele Arsi, while the latest occurred on July 17 and July 30, respectively. The rainy season ended as early as September 10 at both locations, and as late as the third decade of September at Melkassa and October 10 at Negele Arsi. The end of the season showed less variability (CV = 4.1% at Melkassa and 6.3% at Negele Arsi). The length of the growing season ranged from 57 to 106 days at Melkassa and from 49 to 113 days at Negele Arsi, with mean lengths of 79 and 84 days, respectively. A positive trend in the length of the growing season was observed at both sites, with the trend being statistically significant at Negele Arsi (p = 0.027). The probability of experiencing a 5-day dry spell exceeded 50% throughout the main rainy season at both locations. From the 35-year dataset, negative rainfall anomalies were observed in 45.7% (Belg) and 51.4% (Kiremt) of years at Melkassa and 62.8%(Belg) and 54.3% (Kiremt) at Negele Arsi, indicating a high frequency of dry years that threaten rain-fed agriculture. The most extreme negative anomaly (−2.43) was recorded in 2015 at Melkassa, largely attributed to El Niño conditions. Overall, the findings underscore the substantial variability in rainfall and growing season characteristics across the CRV. This has critical implications for agricultural planning, water resource management, and food security, highlighting the urgent need for adaptive and resilient farming strategies in the face of climate variability.
Investigation of genotype x environment interaction for barley Recombinant inbred lines in multi-environments of Tigray, Ethiopia
Abstract
The study examined the impact of 166 barley genotypes on yield performance in Tigray, revealing that year, environmental, and genotype factors significantly influence grain yield per plant (GYP). The analysis used AMMI and GGE biplot models, revealing environment as the dominant factor (95.3%), followed by genotypes (2.8%). The genotypes G126, G60, G108, G64, G52, G12, G62, G104, G47, G10, G83, G66, G39, and G30 were found to be highly productive genotypes showing low interaction with environments (genotypes centered near the origin) for the AMMI2 biplot for the IPCA1 and IPCA2 in GEI. The IPCA1 and average environment coordination (AEC) scores at Mekelle_2018/19 (E3 & E7), Aleasa_2019 (E6), and Habes_2018/19 (E4 & E8) revealed the most stable environments. Though unstable and distant from AEC, Ayba_2018/19 (E1 and E5) significantly contributed to genotype-environment interaction. GGE-biplot of the "which-won-where" showed the 8 environments grouped into 4 mega-environments, with the winning genotypes of each environment being G112 for Ayba_2018, G82 for Aleasa_2018, G25 for Mekelle_2018, G61 for Habes_2018, and G4 for Ayba_2019. Similarly, AMMI biplot analysis revealed high average yields across test locations, with RIL genotypes G36, G72, G25, G118, and G112 showing genetic advancements and potential for future breeding initiatives.
Keywords: AMMI biplot, GGE biplot, Genotype environment interaction, GEI
Disparities in Regional COVID-19 Burden between Asia and Africa: GLM analysis of Real-World Data and Perspectives for Future Outbreak Preparedness
Abstract
Objective. Coronavirus disease 2019 (COVID-19) has caused huge morbidity and mortality globally, with noticeable disparities in resilience capacity as well as health and sociodemographic impacts. Although the end of the pandemic has been declared, infection cases are still being reported worldwide. This study compared the regional disease burden across 30 countries of Asia and Africa, and suggest perspectives for future outbreak preparedness.
Methods. An ecological study was conducted using epidemiological data from reliable country-level COVID-19 databases (John Hopkins University COVID-19 Resource Center, Our World in Data), whereas health and sociodemographic statistics were retrieved from WHO website. Data related to 14 Asian countries (10 Southeast and 4 Eastern countries, China excluded) and 16 states of the Southern African Development and Cooperation (SADC) were used in this study. We calculated country-level case fatality rate (CFR) using cumulative COVID-19 incidence and death cases. Shapiro-Wilk normality test was performed; thereafter, Wilcoxon rank-sum test, given that outcome variables (cumulative incidence, cumulative deaths, CFR as of 3 October 2023). Generalized linear model (GLM) analysis was performed to determine the regional level predictors of COVID-19 morbidity and mortality using Stata statistical software package v.17.
Results. East/Southeast Asia had significantly higher mean cumulative COVID-19 incidence (7,896,093 +/1.08e+07 vs. 392,119.8 +/- 986,323.2; p<0.05) and death cases (35,243.1 +/- 43,398.2 vs. 8,333.3 vs. 25,182.5; p<0.001). SADC region had significantly higher CFR as compared with eastern/southeastern Asia, 1.68 +/- 0.34 vs. 0.87 +/- 1.0 (p<0.05). GLM analysis showed that anti-SARS-CoV2 vaccination coverage rate was inversely associated with COVID-19 CFR (beta= -0.02 +/- 0.01; p<0.001), but neither with COVID-19 incidence nor with COVID-19 mortality. Furthermore, SADC region was positively associated with COVID-19 CFR (coeff.= 0.81 +/- 0.32; p<0.05). COVID-19 incidence was positively associated with age-standardized hypertension prevalence, whereas no association was observed between COVID-19 CFR and country-level prevalence of selected metabolic disorders (hypertension, diabetes, obesity).
Conclusion. Findings suggest that, as of 2023, (1) though East/Southeast Asia region had higher COVID-19 incidence and mortality than SADC region, the latter showed higher odds for COVID-19 CFR, (2) vaccination coverage rate was associated with reduced CFR but not with COVID-19 incidence, (3) hypertension was associated with increased COVID-19 incidence and CFR. SARS-CoV2 continues to circulate alongside with other transmissible viral agents, thus basic hygiene measures should be observed particularly for subjects with impaired metabolic health. Further results will be discussed during the conference.
Keywords: Africa; East Asia; Incidence; Fatality; SARS-CoV2 infection; Southeast Asia.
Characterization and Mapping of Salt Affected Soils and Irrigation Water Quality of Irrigated Lands in Raya Alamata District, Northern Ethiopia.
Abstract
Understanding soil salinity and sodicity, along with the quality of irrigation water is crucial for effective management of irrigated agricultural lands. A study was conducted in the Raya Alamata district at two sites to evaluate and map soil salinity/sodicity levels and assess irrigation water quality. Soil and water samples were collected following a field reconnaissance survey and analyzed for key indicators of salinity, sodicity, and water quality. The sequence of exchangeable cations at both sites followed the order: Ca > Mg > Na > K. In terms of surface soils designated for agriculture, 5.13% (182 ha) in Tumuga and 11.67% (364.5 ha) in Gerjale were classified as saline. Additionally, in Tumuga, 4.96% (176 ha) of the land was identified as saline-sodic and 0.17% (6.03 ha) as sodic. Both sites showed a slight increase in soil pH (pHe) and electrical conductivity (ECe) with soil depth. In deeper layers, ECe values surpassed the threshold levels defining salt-affected soils. Irrigation water analysis showed that at Tumuga and Gerjale, 85.71% and 87.50% of water samples, respectively, were deemed suitable for irrigation, while 14.29% and 12.50% were unsuitable based on residual sodium carbonate content. Continuous assessment and monitoring are recommended to prevent the development of salinity and sodicity issues. Additionally, selecting salt-tolerant crop varieties and using plants capable of lowering the shallow ground water table by extracting near-surface perched water would be beneficial for both sites.
Integrated Community and School Health Program for the Control of HIV/S.T.I. Epidemics in Africa: The HIV/STI "Zero-Risk Initiative"
Abstract
HIV/AIDS remains a leading cause of morbidity and mortality in the sub-Saharan Africa (SSA). The global HIV epidemic is disproportionately concentrated in the SSA (accounting for approximately 75% of all related deaths), a region where behavioral, cultural factors and existing sexually transmitted infections (STIs) represent major risk factors triggering the epidemic. Our previous studies provide scientific evidence on faith-based and cultural factors that paly a protective role against STIs. Here we present recent findings on HIV infection associated high-risk factors and the proposed “Zero-risk Initiative” for SSA countries, a comprehensive, multidisciplinary educational program that addresses local prevalent risk factors, which is susceptible to help to control the HIV/STI epidemics. We collected recent epidemiological data from WHO and research-based findings related to countries of the region. Furthermore, an interdisciplinary panel of researchers and educators gathered available behavioral, spiritual, mental health and sports educational materials to create an integrated program to be implemented in communities and schools. Lesotho (20.5%), Republic of South Africa (16.6%), Mozambique (11.8%), Zimbabwe (11.0%), Zambia (11.7%), the Democratic Republic of the Congo (DRC, 5%) are among countries of the region having high HIV infection prevalence. Younger age of first sex, multiple sex partnership, number of outside/occasional sex partners and religious affiliation were found to be associated with HIV infection, and the association was revealed to be stronger in a number of southern and Central African countries. Zero-Risk Initiative (ZERI), an integrated educational program that promotes physical, moral, spiritual health and sports components, oriented towards fostering self-awareness, self-control and character building. It is susceptible to help prevent the development of high-risk behaviors associated with STIs. A thorough explanation of the ZERI program will be discussed during the conference.
Keywords: Africa; Human immunodeficiency virus (HIV); Sexually transmitted infection (STI).