Prevalence of diarrhoea and risk factors among children under five years old in Mbour,Senegal:a cross-sectional study

Background:Diarrhoeal diseases remain an important cause of mortality and morbidity among children,particularly in low-and middle-income countries.In Senegal,diarrhoea is responsible for 15%of all deaths in children under the age of five and is the third leading cause of childhood deaths.For targeted planning and implementation of prevention strategies,a context-specific understanding of the determinants of diarrhoeal diseases is needed.The aim of this study was to identify risk factors of diarrhoeal diseases in children under the age of five in Mbour,Senegal.Methods:Between February and March 2014,a cross-sectional survey was conducted in four zones of Mbour to estimate the burden of diarrhoeal diseases(i.e.diarrhoea episodes in the 2 weeks preceding the survey)and associated risk factors.The zones covered urban central,peri-central,north peripheral and south peripheral areas.Overall,596 households were surveyed by a questionnaire,yielding information on sociodemographic,environmental and hygiene behavioural factors.Univariable and multivariable logistic regression analyses were used to identify risk factors associated with the occurrence of diarrhoea.Results:The reported prevalence of diarrhoea among children under the age of five during the 2 weeks preceding the survey was 26%.Without adjustment,the highest diarrhoea prevalence rates were observed in the peri-central(44.8%)and urban central zones(36.3%).Multivariable regression revealed significant associations between diarrhoeal diseases and unemployment of mothers(adjusted odds ratio[aOR]=1.62,95%confidence interval[CI]:1.18-2.23),use of open bags for storing household waste(aOR=1.75,95%CI:1.00-3.02),evacuation of household waste in public streets(aOR=2.07,95%CI:1.20-3.55),no treatment of stored drinking water(aOR=1.69,95%CI:1.11-2.56)and use of shared toilets(aOR=1.69,95%CI:1.11-2.56).Conclusion:We found a high prevalence of diarrhoea in children under the age of five in Mbour,with the highest prevalence occurring in the central and peri-central areas.These findings underscore the need for public health interventions to alleviate the burden of diarrhoea among vulnerable groups.Promotion of solid waste disposal and reduction of wastewater exposure should be implemented without delay.

Relationships between soil moisture and dust emissions in a bare sandy soil of Mongolia

This study presents experimental results of the change in threshold friction velocity and dust emission strength as a function of soil moisture content. The dust and soil moisture data were obtained from irrigated plots of a bare, sandy soil （no vegetation） situated in the Mongolian steppe. Dust flux was measured using the PI-SWERL^（R） device, while soil moisture was measured using gravimetric methods. Our results demonstrate the strong controlling effects of soil moisture on both the threshold friction velocity and dust emission strengths. Threshold friction velocity increased from 0.44 m/s for dry soil （0.002 g/g） to 0.67 m/s for wet soil （0.06 g/g）, confirming the importance of soil moisture for controlling dust events. Dust emission strength was significantly depressed for wet soils, starting at a soil moisture value of 0.02 g/g. From these results, we developed a simple dust diagram that may be useful as part of a warning system to identify initial sensitivity to threshold conditions as well as conditions that could lead to potentially significant dust emissions. Overall, the research findings in this study could be used to provide foreknowledge of conditions that would be conducive to high dust emissions for this area of Mongolia.

Monitoring gully erosion in the European Union: A novel approach based on the Land Use/Cover Area frame survey (LUCAS)

The European Commission's Thematic Strategy for Soil Protection(COM(2012)46)identified soil erosion as an important threat to European Union's(EU)soil resources.Gully erosion is an important but hitherto poorly understood component of this threat.Here we present the results of an unprecedented attempt to monitor the occurrence of gully erosion across the EU and UK.We integrate a soil erosion module into the 2018 LUCAS Topsoil Survey,which was conducted to monitor the soil health status across the EU and to support actions to prevent soil degradation.We discuss and explore opportunities to further improve this method.The 2018 LUCAS Topsoil Survey consisted of soil sampling(0-20 cm depth)and erosion observations conducted in ca.10%(n=24,759)of the 238,077 Land Use/Cover Area frame Survey(LUCAS)2018 in-field survey sites.Gully erosion channels were detected for ca.1%(211 sites)of the visited LUCAS Topsoil sites.Commission(false positives,2.5%)and omission errors(false negatives,5.6%)were found to be low and at a level that could not compromise the representativeness of the gully erosion survey.Overall,the findings indicate that the tested 2018 LUCAS Topsoil in-field gully erosion monitoring system is effective for detecting the incidence of gully erosion.The morphogenesis of the mapped gullies suggests that the approach is an effective tool to map permanent gullies,whereas it appears less effective to detect short-lived forms like ephemeral gullies.Spatial patterns emerging from the LUCAS Topsoil field observations provide new insights on typical gully formation sites across the EU and UK.This can help to design further targeted research activities.An extension of this approach to all LUCAS sites of 2022 would significantly enhance our understanding of the geographical distribution of gully erosion processes across the EU.Repeated every three years,LUCAS soil erosion surveys would contribute to assess the state of gully erosion in the EU over time.It will also enable monitoring and eventually predicting the dynamics of gully erosion.Data collected were part of the publicly available Gully Erosion LUCAS visual assessment(GE-LUCAS v1.0)inventory.