Nyiragongo volcano is known for its active lava lake and for socioeconomic issues arising from future possible eruptive events having major impacts on the community living in the Virunga region. The ...2020 field expedition inside the summit crater has allowed the collection of unprecedented field observations to state on the current activity. Since the February 2016 intracrater event, the crater floor level has been rising much faster than during the 2010–2016 period. The current activity is reminiscent of the 1970–1972 and 1994–1995 periods preceding the lava lake drainage events in 1977 and 2002. Numerical simulations, successfully validated with data over the past 30 years, show that the rising of the crater floor could slow down in the next months/years and reach a critical equilibrium. Based on the past eruptive history and on the current activity, a flank eruption in the March 2024 to November 2027 interval could be a possible scenario.
Plain Language Summary
Nyiragongo volcano hosts within its crater the world's largest continuously active lava lake. This constitutes major socioeconomic issues which arise from future possible eruptive events having a catastrophic impact to the Virunga volcanic region's growing community within the Democratic Republic of Congo (DRC) and Rwanda, particularly the cities of Goma and Gisenyi with about 1.5 million people living at its foot. The 2020 field expedition inside the summit crater allowed the collection of unprecedented field observations to state on the current eruptive activity. Since a new and unusual eruptive event occurred on 29 February 2016, the crater floor level has been rising much faster than during the 2010–2016 period. The current activity is reminiscent of the 1970–1972 and 1994–1995 periods preceding the lava lake drainage events in 1977 and 2002, respectively. Numerical simulations, successfully validated with data over the past 30 years, show that the rising of the crater floor could slow down in the next months/years and reach a precarious balance. Based on the past eruptive history and on the current activity, we stress that a flank eruption in the March 2024 to November 2027 interval could be a possible scenario.
Key Points
Current eruptive activity at Nyiragongo mirrors that observed in 1970–1972 and 1994–1995
Activity forecasting is backed up by simulations of a mathematical model
Based on the forecast failure model, a new lava lake drainage in the March 2024 to November 2027 interval could be a possible scenario
Human-induced fire is one of the most important determinants of forest cover and change in tropical and subtropical regions of the world. Yet its impact on forest cover and forest cover change ...remains unclear, as fires in Africa generally do not spread over very large area. This is particularly the case in the Democratic Republic of Congo (DRC), a region of the world that is still poorly investigated. Here, we propose to study the effect of human-induced fire on land use and land cover change in a protected area of the DRC, i.e. the Luki Biosphere Reserve (LBR). We investigate tree cover changes in and around the reserve between 2002 and 2019 using Landsat 7 ETM+, Landsat 8 OLI/TIRS and MODIS MCD12Q1 images and quantify human induced fires using MODIS MCD64A1 images. The study combines land use and land cover (LULC) change detection analysis of four images, two acquired in 2002 and two acquired in 2019, with multi-temporal assessment of annual burnt area acquired between 2002 and 2019 from MODIS MCD64A1 to assess the role of fire in LULC changes and the sensitivity of different LULC types to fire. The results show a dynamic conversion of primary forest to secondary forest over about 16% of the area, the evolution of savanna to secondary forest over 9.6% (Landsat image) and the replacement of secondary forest by savanna over 8.1% (MODIS image) of the total area of Luki Reserve. Of the total area undergoing land use change, 34.1% (Landsat image) and 35.7% (MODIS image) were caused by fire, which however did not cause a significant LULC change. For the LULC types that experienced fire events, the least stable type was primary forest, which had the lowest stability rate (34.2% and 23% for Landsat and MODIS image analysis, respectively) compared to others. This result illustrates the importance of fire as a driver of primary forest loss and degradation in the region. Despite the high exposure of savannas to fire events, they were not significantly destabilized by fire (stability rates of 86.3 and 97% for Landsat and MODIS analysis, respectively). Future analyses should focus on discriminating between different fire types to better understand the complex relationship between fire and ecosystem conditions.
Women living with HIV (WLWH) face unique reproductive health (RH) barriers which increase their risks of unmet need for contraception, contraceptive failure, unintended pregnancy, and ...pregnancy-related morbidity and mortality and may prevent them from achieving their reproductive goals. Patient-centered counseling interventions that support health care workers (HCWs) in providing high-quality RH counseling, tailored to the needs of WLWH, may improve reproductive health outcomes.
We are conducting a non-blinded cluster randomized controlled trial (cRCT) of a digital health intervention for WLWH (clinicaltrials.gov #NCT05285670). We will enroll 3,300 WLWH seeking care in 10 HIV care and treatment centers in Nairobi and Western Kenya. WLWH at intervention sites receive the Mobile WACh Empower intervention, a tablet-based RH decision-support counseling tool administered at baseline and SMS support during two years of follow-up. WLWH at control sites receive the standard of care FP counseling. The decision-support tool is a logic-based tool for family planning (FP) counseling that uses branching logic to guide RH questions based on participants' reproductive life plans, tailoring counseling based on the responses. Follow-up SMSs are based in the Information-Motivation-Behavioral (IMB) Skills model of behavioral change and are tailored to participant characteristics and reproductive needs through separate SMS "tracks". Follow-up visits are scheduled quarterly for 2 years to assess plans for pregnancy, pregnancy prevention, and contraceptive use. The primary outcome, FP discontinuation, will be compared using an intent-to-treat analysis. We will also assess the unmet need for FP, dual method use, viral load suppression at conception and unintended pregnancy.
The Mobile WACh Empower intervention is innovative as it combines a patient-centered counseling tool to support initial reproductive life decisions with longitudinal SMS for continued RH support and may help provide RH care within the context of provision of HIV care.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In the Lake Kivu region, water erosion is the main driver for soil degradation, but observational data to quantify the extent and to assess the spatial-temporal dynamics of the controlling factors ...are hardly available. In particular, high spatial and temporal resolution rainfall data are essential as precipitation is the driving force of soil erosion. In this study, we evaluated to what extent high temporal resolution data from the TAHMO network (with poor spatial and long-term coverage) can be combined with low temporal resolution data (with a high spatial density covering long periods of time) to improve rainfall erosivity assessments. To this end, 5 minute rainfall data from TAHMO stations in the Lake Kivu region, representing ca. 37 observation-years, were analyzed. The analysis of the TAHMO data showed that rainfall erosivity was mainly controlled by rainfall amount and elevation and that this relation was different for the dry and wet season. By combining high and low temporal resolution databases and a set of spatial covariates, an environmental regression approach (GAM) was used to assess the spatiotemporal patterns of rainfall erosivity for the whole region. A validation procedure showed relatively good predictions for most months (R2 between 0.50 and 0.80), while the model was less performant for the wettest (April) and two driest months (July and August) (R2 between 0.24 and 0.38). The predicted annual erosivity was highly variable with a range between 2000 and 9000 MJ mm ha−1 h−1 yr−1 and showed a pronounced east–west gradient which is strongly influenced by local topography. This study showed that the combination of high and low temporal resolution rainfall data and spatial prediction models can be used to improve the assessments of monthly and annual rainfall erosivity patterns that are grounded in locally calibrated and validated data.
The recognition and reputation of scientists and academic institutions are well-established in the field of scientometrics. However, these aspects face criticism in regions with limited information ...access and considered underdeveloped. In this study, we aimed to discuss the research performance of young universities (YU) in these challenging contexts. Despite financial, socio-economic, and political struggle, research in these YU has not stagnated and has even produced renowned scientists with global reputation. Our focus is on a case study of a Congolese YU, the Université Evangélique en Afrique (UEA), operating in a conflict-affected zone. The results showed that factors such as capacity building, infrastructure development, funding opportunities, collaborative partnerships, monitoring and evaluation are the main factors boosting the institution viability. Other important factors included scientific publication dynamics, community engagement, and policies for long-term sustainability, and should be reinforced in young central Africa universities to secure prominent positions in the global arena. The case study of UEA demonstrated that there is still room for revitalizing education and research in YU in the Global South. By accumulating citations and calculating the H-index using tools such as “Publish or Perish” and Scopus, this study suggests that platforms such as Google Scholar or ResearchGate alone are inadequate for evaluating research in academic institutions and researchers. Efforts are needed in these YU to promote quality research and minimize waste of data by publishing in predatory journals. This study also suggests that though scientometric indicators are effective in securing a prominent position in the global arena for YU, they are not solely adequate. Grey reports should also be integrated to assess YU's community engagement and real impact of conducted research at the local and national levels. Despite challenges, these academic institutions provide valuable services to the community, and its researchers actively collaborate on research projects at regional, continental, and global scales. This study contribute to the limited existing literature on quality of education and research in developing central Africa regions by providing a comprehensive understanding through a detailed case study.
Objective
To examine environmental and human factors that affect the spatial and temporal dynamism of malaria in DRC’s South‐Kivu province.
Methods
In a cross‐sectional study conducted between 1 ...January 2010 and 31 December 2015, spatial distribution was determined through thematic maps of malaria attack rate. SatScan ™ software and Monte Carlo test were used to identify spatial risk clusters. Temporal evolutions were analysed using the Cleveland algorithm. Generalized Additive Models for Location Scale and Shape and negative binomial regression were used to assess the independent human and environmental factors associated with incident malaria.
Results
The cumulative annual incidence of malaria increased from 10 968/100 000 in 2013 to 15 501/100 000 in 2015 (P for trend ˂0.001); malaria lethality increased from 0.1% in 2013 to 0.3% in 2015 (P for trend = 0.62). Between 2010 and 2015, 18 of 34 health zones consistently reported the highest attack rates, which ranged from 25 000 to 50 000/100 000. Four risk clusters areas were identified, with relative risk (RR) of 1.2 to 3.0, from which malaria was reported continuously during each year. Factors significantly associated with malaria cases were agro‐pisciculture practices (Incidence Risk Ratio IRR: 1.96; 95% CI: 1.23–3.13) and the presence of a lake in the health zone (IRR: 2.48, 95% CI: 1.51–4.42).
Conclusions
Malaria control in this setting must be intensified in peri‐lacustrine areas and those in which the population is intensively engaged in standing water‐associated activities.
Objectif
Examiner les facteurs environnementaux et humains qui affectent le dynamisme spatial et temporel du paludisme dans la province du Sud‐Kivu en RDC.
Méthodes
Dans une étude transversale menée entre le 1er janvier 2010 et le 31 décembre 2015, la distribution spatiale a été déterminée à l'aide de cartes thématiques du taux de cas de paludisme. Le logiciel SatScan™ et le test Monte Carlo ont été utilisés pour identifier les grappes de risques spatiaux. Les évolutions temporelles ont été analysées à l'aide de l'algorithme de Cleveland. Des modèles additifs généralisés pour l'échelle et la forme de l'emplacement et la régression binomiale négative ont été utilisés pour évaluer les facteurs humains et environnementaux indépendants associés à l’incidence du paludisme.
Résultats
L'incidence annuelle cumulée du paludisme est passée de 10.968/100 000 en 2013 à 15.501/100 000 en 2015 (p pour la tendance ˂0,001); la létalité du paludisme est passée de 0,1% en 2013 à 0,3% en 2015 (p pour tendance = 0,62). Entre 2010 et 2015, 18 des 34 zones de santé ont constamment rapporté des taux de cas les plus élevés, qui variaient de 25.000 à 50.000/100 000. Quatre zones de risques de grappes ont été identifiées, avec un risque relatif (RR) de 1,2 à 3,0 à partir desquelles le paludisme a été rapporté en continu chaque année. Les facteurs significativement associés aux cas de paludisme étaient: les pratiques agro‐piscicoles (Ratio d’Incidence de Risque IRR: 1,96 ; IC95%: 1,23‐3,13) et la présence d'un lac dans la zone de santé (TRI: 2,48 ; IC95%: 1,51‐4,42).
Conclusions
La lutte contre le paludisme dans ce contexte doit être intensifiée dans les zones péri‐lacustres et celles dans lesquelles la population est intensément engagée dans des activités liées à l'eau stagnante.
Ideally, in a country the population censuses are held regularly (five or ten-year intervals), population surveys, called “control surveys” are then conducted during the intercensal period. The ...latter, as well as the registers of civil status (information on the movements of the population), help determining a representative sample, called “scale model of the population.” Random, stratified and weighted, it has the advantage of providing a good statistical database for any generalizations about the target population with relatively little risk of error. Our study area, Bukavu city, doesn't comply with the classical scheme of data collection for two main reasons: - there are more than twenty years that real demographic censuses have been carried out in the province, the records of the `civil status is poorly maintained and often incomplete—if any!—Especially during this post-conflict period. A study was conducted in Bukavu City to determine the number of people living in this city. Two GeoEye satellite images of 50 cm resolution captured in July 2012 were used. A net of 200 × 200 meters was created with ArcGIS to divide the satellite images into regular cells. In total 2772 cells were created to cover the two satellite images but only 2353 cells were considered for classification. Three classes were identified in the satellite images according to houses density: High density, medium density and low density zones. Three samples were selected and for each different density type, a point map was created covering each house of the selected sample zones received a point. Using the three different density patterns, 95 highly populated zones were identified, 307 medium density zones and 800 low density zones having each respectively a total of 30'400, 46'050, and 40'000 houses. The population of the city was obtained by taking the number of houses times an average of 8, 7 and 6 habitants per house respectively in high, medium and low density zones. A total of 805550 habitants was obtained for Bukavu city which is almost the same number of people estimated (830'000) by the Inspection Provinciale de la Santé which is the health office in charge of vaccination campaign in South-Kivu Province. This method can be used whenever there is a need to quickly estimate the number of the population in a region where there is no census data.
Les marais sont de plus en plus menacés par les activités anthropogéniques mettant en péril leur capacité de filtrant des eaux des bassins versants. Cette étude a permis de déterminer l’efficacité de ...rétention des nutriments par les marais de Ciranga et de Kabamba et les effets de l’utilisation des terres et de la végétation sur la rétention des nutriments. Les échantillons d’eau ont été prélevés à l’entrée de la rivière dans le marais et à l’embouchure, et aussi sur sept stations identifiées dans le marais caractérisées par différents types de végétation et d’utilisation. Les prélèvements ont été effectués mensuellement entre août 2011 et juillet 2012. L’efficacité de rétention relative des polluants a été calculée par la différence entre la concentration au site de à l’entrée du marais et celle au site récepteur. Les résultats montrent que l’efficacité de rétention des nutriments des marais de Ciranga et de Kabamba diffèrent au vu de leur état d’utilisation des terres et de la couverture végétale. Le marais de Ciranga a une potentialité de rétention des nutriments plus élevée que le marais de Kabamba. L’efficacité de rétention du marais Ciranga est de 13% pour l’azote, mais celui de Kabamba est de 2% pour le phosphore. Le marais de Ciranga possède une concentration élevée en phosphore dans la rivière Lwiro (0,5 µmole/l). Par ailleurs, la rétention d’azote total est plus significative dans le marais de Kabamba que dans le marais de Ciranga. Comme le marais de Kabamba a été drainé et transformé en terre de culture, sa fonction naturelle de purification a été réduite. Des mesures de restauration des marais seraient d’une grande importance pour la stabilité du Lac Kivu et d’autres écosystèmes importants de la région.
Cette étude a été conduite afin d’évaluer les risques pour la santé liés à la production de déchets en milieu rural d’Irhambi Katana à l’est de la République Démocratique du Congo (RDC). La mesure ...des quantités des déchets produits par ménage dans six localités du groupement d’Irhambi Katana et l’analyse microscopique des échantillons des déchets ont été réalisées. La comparaison avec les données des centres de santé et la détermination de l’apport de ces déchets en éléments nutritifs du sol ont été réalisées. Les ménages du groupement d’Irhambi Katana produisent en moyenne 0,3 kg de déchets par jour. Ces déchets domestiques renferment plusieurs agents pathogènes tels que Balantidium coli, Shigella flexneri, Ascaris lombricoïdes et Escherichia coli qu’on peut associer à des maladies diarrhéiques couramment rencontrées dans les statistiques des centres de santé comme l’ascaridiose, la shigelose, l’amibiase et le choléra. Mais aussi ces déchets contiennent des matières organiques fertilisantes du sol comme l’azote et le phosphore en quantité importante (1272 mg P/kg; 8,89 % de N /kg). Une sensibilisation de la population dans la gestion des déchets domestiques pour éviter les maladies dues à la mauvaise gestion des déchets ainsi que l’usage de ces déchets dans la fertilisation des sols est recommandée.
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