Determination of Surface Water Quality Status and Identifying Potential Pollution Sources of Lake Tana: Particular Emphasis on the Lake Boundary of Bahirdar City, Amhara Region, North West Ethiopia, 2013

Background: The water quality of Lake Tana is influenced by environmental stress and anthropogenic activities. Point and non-point sources are the major factors which affect the quality of the lake. Objectives: To determine surface water quality status of Lake Tana and to identify the potential pollution sources bound to Bahirdar City Administration, Ethiopia. Methodology: Laboratory based cross – sectional study was conducted in order to assess the quality and to identify the potential pollution sources of the lake. Geo referenced water samples were collected at eight sampling stations. Repeated water samples were collected and analyzed. Result: The common water quality monitoring parameter were analysed, very low dissolved oxygen (3.5 mg/l) and high biochemical oxygen demand (23.7mg/l) were investigated in severely stressed sites. In addition to these, enriched nutrient like phosphorus and nitrate were identified to a level that influences algal growth. According to microbial analysis, total coli forms >180mg/100ml and Escherichia coli type one were isolated. Conclusions: The Canadian Water Quality Index result categorizes the lake as poor state to aquatic life, recreation and drinking. Keywords: Water quality, Lake, surface water, Water pollution, Point source pollution, Water Quality Inde

Citrus Production, Constraints and Management Practices in Ethiopia: The Case of Pseudocercospora Leaf and Fruit Spot Disease

Citrus is economically important fruit crop in Ethiopia. However, its production is seriously constrained by various diseases including Pseudocercospora leaf and fruit spot. Surveys were conducted between June 2012 and May 2013 in the main citrus production areas of the country to assess the spread of the disease, and to determine its incidence and severity. A total of forty-nine citrus orchards in twenty-eight districts were surveyed. Random sampling techniques were used for data collection. The results showed that the disease had prevailed and widely spread in the districts assessed in the wet humid areas of the south, southwest, northwest, and north central parts, but not in the low altitude drier areas of the central rift valley and the eastern region of the country. Accordingly, 63.3% of the orchards surveyed were infected with the disease. The overall mean incidences of the disease on leaves of sweet orange, mandarin, lemon and lime were 36.2, 21.5, 17.1 and 16.3% while disease severity ratings were 2.6, 2.3, 2.0 and 1.7, respectively. Similarly, the average incidences and severities on fruits were 63.8, 29.4, 18.0 and 16.7%, and 4.0, 3.0, 2.0 and 2.0, in the same order. However, disease incidences in the different orchards ranged from zero to 76.7% on leaves and from zero to 100% on fruits. Disease severity ratings also varied from one to five on both leaves and fruits. In general, citrus orchards in the south and southwest Ethiopia that are known to have high rainfall and humidity conditions were more severely affected by the disease than those in the northwest and north central parts of the country. In these areas, respondents indicated that many farmers completely abandoned their citrus trees due to this disease. The causative agent was also identified to be the fungus Pseudocercospora angolensis based on cultural and morphological characteristics, and pathogenicity tests of representative isolates obtained from infected leaf and fruit samples.Keywords: Citrus Leaf and fruit spot disease; Pseudocercospora angolensis; Ethiopi

Evolution of salinity and water table level of the phreatic coastal aquifer of the Emilia Romagna region (Italy)

The coastal aquifers of the Mediterranean region are highly susceptible to seawater intrusion due to a combination of challenges such as land subsidence, high aquifer permeability, urbanization, drainage, and an unsustainable use of water during the dry summer months. The present study is focused on a statistical analysis of groundwater data to evaluate the spatial changes of water level and electrical conductivity in the coastal phreatic aquifer of the Emilia-Romagna (Northeast Italy) for the period from 2009 to 2018. Data from 35 wells distributed across the entire regional coastal area are used to establish a temporal trend, as well as correlations between salinity, water table level, and rainfall. Water table and salinity distribution maps for the entire study area are discussed regarding surface geology and water management. Most of the wells are in the beach wedge sand unit, which allows for easy connectivity between groundwater and surface water. Surface water and groundwater salinization are enhanced along the surface water bodies connected to the sea. The lowest water table level occurs in the western and northern parts of the study area, because of the semiconfined behavior of the aquifer. Only in the northernmost, close to the Po River, and in the southernmost parts of the study area does the groundwater remain fresh for the whole period considered due to river aquifer recharge. In the rest of the region, the thickness of freshwater lenses, where present, is less than 4.5 m. The existence of a water table level below sea level and high saline water at the bottom of the aquifer in most of the study area suggest that the aquifer is in unstable hydrodynamic conditions and groundwater quality is not fit for human consumption or for irrigation. This study is the first to provide a regional overview of the state of groundwater level and salinization within the coastal aquifer of the Emilia-Romagna Region; it also suggests that, overall, the salinization trend has slightly decreased from 2009 to 2018

Potential of Water Hyacinth Infestation on Lake Tana, Ethiopia: A Prediction Using a GIS-Based Multi-Criteria Technique

Water hyacinth is a well-known invasive weed in lakes across the world and harms the aquatic environment. Since 2011, the weed has invaded Lake Tana substantially posing a challenge to the ecosystem services of the lake. The major factors which affect the growth of the weed are phosphorus, nitrogen, temperature, pH, salinity, and lake depth. Understanding and investigating the hotspot areas is vital to predict the areas for proper planning of interventions. The main objective of this study is therefore to predict the hotspot areas of the water hyacinth over the surface of the lake using the geographical information system (GIS)-based multi-criteria evaluation (MCE) technique. The main parameters used in the multi-criteria analysis were total phosphorus (\u3e0.08 mg L−1), total nitrogen (\u3e1.1 mg L−1), temperature (\u3c26.2 °C), pH (\u3c8.6), salinity (\u3c0.011%), and depth (\u3c6 m). These parameters were collected from 143 sampling sites on the lake in August, December (2016), and March (2017). Fuzzy overlay spatial analysis was used to overlay the different parameters to obtain the final prediction map of water hyacinth infestation areas. The results indicated that 24,969 ha (8.1%), 21,568.7 ha (7.1%), and 24,036 ha (7.9%) of the lake are susceptible to invasion by the water hyacinth in August, December, and March, respectively. At the maximum historical lake level, 30,728.4 ha will be the potential susceptible area for water hyacinth growth and expansion at the end of the rainy season in August. According to the result of this study, the north and northeastern parts of the lake are highly susceptible for invasion. Hence, water hyacinth management and control plans shall mainly focus on the north and northeastern part of Lake Tana and upstream contributing watersheds

Impact of Soil Conservation and Eucalyptus on Hydrology and Soil Loss in the Ethiopian Highlands

The Ethiopian highlands suffer from severe land degradation, including erosion. In response, the Ethiopian government has implemented soil and water conservation practices (SWCPs). At the same time, due to its economic value, the acreage of eucalyptus has expanded, with croplands and pastures converted to eucalyptus plantations. The impact of these changes on soil loss has not been investigated experimentally. The objective of this study, therefore, is to examine the impacts of these changes on stream discharge and sediment load in a sub-humid watershed. The study covers a nine-year period that included installation of SWCPs, a three-fold increase from 1.5 ha in 2010 to 5 ha in 2018 in eucalyptus, and the upgrading of an unpaved to the paved road. Precipitation, runoff, and sediment concentration were monitored by installing weirs at the outlets of the main and four nested watersheds. A total of 867 storm events were collected in the nine years. Runoff and sediment concentration decreased by more than half in nine years. In the main watershed W5, we estimated that evapotranspiration by eucalyptus during the dry phase (November to May) increased approximately from 30 mm a−1 in 2010 to 100 mm a−1 in 2018. In watershed W3 it increased from 2 mm a−1 to 400 mm a−1, requiring more rainfall before saturation excess runoff began in the rain phase. The reduction in runoff led to a decreased sediment load from 70 Mg ha−1 a−1 in 2010 to 2.8 Mg ha−1 a−1 in 2018, though the reduction in discharge may have negative impacts on ecology and downstream water resources. SWCPs became sediment-filled and minimally effective by 2018. This indicates that these techniques are either inappropriate for this sub-humid watershed or require improved design and maintenance

Training on Scaling of Climate-Smart Washera and Wollo Sheep Breed Improvement Program

The International Center for Agricultural Research in the Dry Areas (ICARDA), The Amhara Regional Agricultural Research Institute (ARARI), the Accelerating the Impact of CGIAR Climate Research in Africa (AICCRA), and the Amhara Livestock and Fisheries Resource Development Office organized a workshop that took place on May 29, 2023, in Bahir Dar Ethiopia. The main goals of the workshop were assessing the advancements of already running community-based breeding programs (CBBPs) and recently formed production Units (PUs) and training livestock development agents and extension workers on managing and establishing production unit sites. The training course was attended by livestock from 16 districts in the Wollo and Gojjam areas, universities, ARARI, and regional and district-level livestock offices. Dr. Likawent Yeheyis, Deputy Director General of ARARI, gave a welcome and opening address to kick off the session. Mulatu Dagnew from the Regional Livestock Office, Asemu Tesfa from the Andassa Research Center, and Tesfaye Getachew from ICARDA each gave a presentation following that. Presentations helped to understand the development and status of CBBPs and PUs, as well as helped to understand how to create and maintain PU sites and breeding tram utilization modality. In the WaWo scaling project, 4280 households in CBBPs and Pu sites have access to the climate-smart breeding program. The training was attended by 67 people in total, 17 of them were women

End-point definition and trial design to advance tuberculosis vaccine development

Tuberculosis (TB) remains a leading infectious cause of death worldwide and the coronavirus disease 2019 pandemic has negatively impacted the global TB burden of disease indicators. If the targets of TB mortality and incidence reduction set by the international community are to be met, new more effective adult and adolescent TB vaccines are urgently needed. There are several new vaccine candidates at different stages of clinical development. Given the limited funding for vaccine development, it is crucial that trial designs are as efficient as possible. Prevention of infection (POI) approaches offer an attractive opportunity to accelerate new candidate vaccines to advance into large and expensive prevention of disease (POD) efficacy trials. However, POI approaches are limited by imperfect current tools to measure Mycobacterium tuberculosis infection end-points. POD trials need to carefully consider the type and number of microbiological tests that define TB disease and, if efficacy against subclinical (asymptomatic) TB disease is to be tested, POD trials need to explore how best to define and measure this form of TB. Prevention of recurrence trials are an alternative approach to generate proof of concept for efficacy, but optimal timing of vaccination relative to treatment must still be explored. Novel and efficient approaches to efficacy trial design, in addition to an increasing number of candidates entering phase 2-3 trials, would accelerate the long-standing quest for a new TB vaccine

Risk factors for Group B Streptococcus colonisation and disease in Gambian women and their infants.

OBJECTIVES: To determine risk factors for GBS colonisation in Gambian mothers and in their infants from birth to day 60-89 of age. METHODS: Swabs and breastmilk from mothers/infant pairs were collected and cultured on selective agar. Negative samples were analysed for GBS DNA via real-time PCR. Positive isolates were serotyped using multiplex PCR and gel-agarose electrophoresis. RESULTS: Seven hundred and fifty women/infant pairs were recruited. 253 women (33.7%) were GBS-colonised at delivery. The predominant serotypes were: V (55%), II (16%), III (10%), Ia (8%) and Ib (8%). 186 infants were colonised (24.8%) at birth, 181 (24.1%) at 6 days and 96 at day 60-89 (14%). Infants born before 34 weeks of gestation and to women with rectovaginal and breastmilk colonisation at delivery had increased odds of GBS colonisation at birth. Season of birth was associated with increased odds of persistent infant GBS colonisation (dry season vs. wet season AOR 2.9; 95% CI 1.6-5.2). CONCLUSION: GBS colonisation is common in Gambian women at delivery and in their infants to day 60-89 and is dominated by serotype V. In addition to maternal colonisation, breastmilk and season of birth are important risk factors for infant GBS colonisation

Epidemiology of invasive group B streptococcal disease in infants from urban area of South China, 2011–2014

YesBackground: Group B Streptococcus (GBS) is a leading cause of morbidity and mortality in infants in both developed and developing countries. To our knowledge, only a few studies have been reported the clinical features, treatment and outcomes of the GBS disease in China. The severity of neonatal GBS disease in China remains unclear. Population-based surveillance in China is therefore required. Methods: We retrospectively collected data of <3 months old infants with culture-positive GBS in sterile samples from three large urban tertiary hospitals in South China from Jan 2011 to Dec 2014. The GBS isolates and their antibiotic susceptibility were routinely identified in clinical laboratories in participating hospitals. Serotyping and multi-locus sequence typing (MLST) were also conducted for further analysis of the neonatal GBS disease. Results: Total 70 cases of culture-confirmed invasive GBS infection were identified from 127,206 live births born in studying hospitals, giving an overall incidence of 0.55 per 1000 live births (95% confidence interval [CI] 0.44–0.69). They consisted of 49 with early-onset disease (EOD, 0.39 per 1000 live births (95% CI 0.29–0.51)) and 21 with late-onset disease (LOD, 0.17 per 1000 live births (95% CI 0.11–0.25)). The incidence of EOD increased significantly over the studying period. Five infants (4 EOD and 1 LOD) died before discharge giving a mortality rate of 7.1% and five infants (7.1%, 2 EOD and 3 LOD) had neurological sequelae. Within 68 GBS isolates from GBS cases who born in the studying hospitals or elsewhere, serotype III accounted for 77.9%, followed by Ib (14.7%), V (4.4%), and Ia (2.9%). MLST analysis revealed the presence of 13 different sequence types among the 68 GBS isolates and ST-17 was the most frequent sequence type (63.2%). All isolates were susceptible to penicillin, ceftriaxone, vancomycin and linezolid, while 57.4% and 51.5% were resistant to erythromycin and clindamycin, respectively. Conclusions: This study gains the insight into the spectrum of GBS infection in south China which will facilitate the development of the guidance for reasonable antibiotics usage and will provide evidence for the implementation of potential GBS vaccines in the future.Supported by medical and health science and technology projects of Health and Family Planning Commission of Guangzhou Municipality (grant number 20151A010034) and Guangdong provincial science and technology planning projects (grant number 2014A020212520)