Landscape pattern analysis using GIS and remote sensing to diagnose soil erosion and nutrient availability in two agroecological zones of Southern Mali

Background Soil is a basic natural resource for the existence of life on earth, and its health is a major concern for rural livelihoods. Poor soil health is directly associated with reduced agricultural land productivity in many subSaharan countries, such as Mali. Agricultural land is subjected to immense degradation and the loss of important soil nutrients due to soil erosion. The objective of the study was to diagnose the spatial distribution of soil erosion and soil nutrient variations under diferent land use in two agroecological zones of Southern Mali using the Geographical Information System (GIS) software, the empirically derived relationship of the Revised Universal Soil Loss Equation, in-situ soil data measurement and satellite products. The soil erosion efect on agricultural land productivity was discussed to highlight the usefulness of soil and water conservation practices in Southern Mali. Results The results of the land use and land cover change analysis from 2015 to 2019 revealed signifcant area reductions in water bodies, bare land, and savanna woodland for the beneft of increased natural vegetation and agricultural land. There was signifcant variation in the annual soil loss under the diferent land use conditions. Despite recordings of the lowest soil erosion rates in the majority of the landscape (71%) as a result of feld-based soil and water conservation practices, the highest rates of erosion were seen in agricultural felds, resulting in a reduction in agricultural land area and a loss of nutrients that are useful for plant growth. Spatial nutrient modelling and mapping revealed a high defciency and signifcant variations (p<0.05) in nitrogen (N), phosphorus (P), potassium (K), and carbon (C) in all land use and land cover types for the two agroecologies. Conclusions The study highlighted the inadequacies of existing feld-based soil and water conservation practices to reduce soil erosion and improve landscape management practices. The fndings of the study can inform land management planners and other development actors to strategize and prioritize landscape-based intervention practices and protect catchment areas from severe erosion for the enhanced productivity of agricultural felds

Spatiotemporal Response of Vegetation to Rainfall and Air Temperature Fluctuations in the Sahel: Case Study in the Forest Reserve of Fina, Mali

Forests constitute a key component of the Earth system but the sustainability of the forest reserves in the semi-arid zone is a real concern since its vegetation is very sensitive to the climate fluctuation. The understanding of the mechanisms for the vegetation–climate interaction is poorly studied in the context of African Sahel. In this study, the characteristics of the vegetation response to the fluctuations of precipitation and temperature is determined for the forest reserve of Fina. Rainfall estimates, air temperature and NDVI were re-gridded to a same spatial resolution and standardized with respect to their respective long-term mean. Lag-correlations analysis was used to estimate lag times between changes of climate variables and vegetation response at both seasonal and interannual bases. Results show increasing tendency of NDVI started from the 1990s coinciding the recovery of the rainfall from the 1980s drought, and the obtained correlation (r = 0.66) is statistically significant (p value < 0.01). The strongest responses of vegetation to rainfall and temperature fluctuations were found after 30 and 15 days, respectively. Moreover, at a shorter time lag (e.g., 15 days), more pronounced vegetation responses to both rainfall and temperature were found in agriculturally dominated land while at a longer time lag (e.g., 30 days), a stronger response was observed in Bare-dominated land. The vegetation response to the climate fluctuation is modulated by the land-use/cover dynamics

Prevalence of Salmonella and their antibiotic susceptibility patterns in the District of Abidjan, Côte d’Ivoire

A study was conducted to estimate the prevalence, antibiotic susceptibility and distribution of Salmonella strains in raw chicken gizzards in 11 municipalities (Abobo, Adjame, Anyama, Attecoube, Bingerville, Cocody, Koumassi, Marcory, Port-Bouet, Treichville and Yopougon) in the District of Abidjan. Sixty six (66) samples of chicken gizzards were collected between April and September 2012. From the total of 66 samples tested,  Salmonella was isolated in 77.27% (51/66). One hundred and four strains (104) were isolated and fifteen distinct serotypes identified: Derby (18.9 %), Budapest (17%), Essen and S. Kentucky (11.3%), Hadar (9.4%), Agona (7.5%), Chester, Ruiru, Schwarzengrund (3.8%), Aoto, Bargny, Elisabethville, Fortune, Poeslderf and Santiago (1.9%). Serogroup O:4 was the most prevalent (67.3 %). Prevalence of other serogroups were 18.3% for O:8, 10.6% for O:3,10, 1.9% for O:21, 1% for O:1,3,19 and O:13. Antibiotic profiles of Salmonella spp. showed 93.37 % of resistance to cotrimoxazole, 73.08% to tetracycline, 46.15% to ticarcilline, 35.58% to nalidixic acid and resistance rates . 30% to chloramphenicol and  ciprofloxacin. Strains were found susceptible to cefoxitim (100%),  cefotaxim (99.04 %), cephalotin (90.38%), amoxicillin and  amoxicillin/clavulanic acid (92.31%) and gentamycin (89.42%).Keywords: Salmonella, raw chicken gizzards, serogroups, antibiotic susceptibility, Cote dfIvoire

Contour bunding technology-evidence and experience in the semiarid region of southern Mali

Land and water management practices have been widely implemented in rural Mali since the 1980s to improve agricultural productivity and erosion control. Under conditions of recurring droughts, these practices are expected to increase farmers’ ability to cope with shocks. One of the most common practices applied in the central and southern parts of Mali is contour bunding (CB). In this study the impact of the CB technology is evaluated with a focus on biophysical and socio-economic benefits. Data were collected in two agro-ecologies of southern Mali and were generated through field experimentation and household survey. Field experimentation involved implementation of contour lines with farm ridges, agronomic trails and runoff and erosion measurements. Agronomic data was collected on sorghum, maize, groundnut and millet for three consecutive years (2015 to 2017). Socio-economic data on the use of CB was obtained from individual farmer surveys. CB involves the layout of contour lines with land leveling devices to identify points of equal elevation and construction of contour lines with draught animals and human labor. The majority of the labor input to construct and maintain the CB comes from adult men who are head of the household (58%) and youth male (33%). Results indicate that with the application of CB yield of crops was higher with the highest increase in grain yield and biomass obtained for maize and millet (P < 0.01). CB application was useful in retaining soil water and reduced erosion rate. In treatment fields, 162mmof rainfall per year was saved as soil moisture and on average 13,090 kg per hectare of soil was lost from farm fields without CB, and CB implementation significantly reduced the soil loss by 163% (P < 0.01). The improvements in crops yield and biomass, and the retention of soil nutrients positively changed farm level productivity conditions. The majority of farmers (78%) perceived higher income from the sale of crops grown on CB plots. These results suggest the landscape wide application of CB

Effet protecteur des feuilles de Opilia celtidifolia contre l’ulcère induit par l’éthanol chez le rat

Opilia celtidifolia est une plante traditionnellement utilisée contre les plaies et l’ulcère gastro duodénal. Le but de ce travail était d’étudier l’activité antiulcéreuse des extraits aqueux de cette de la plante. Des extraits aqueux, total et épuisé, ont été préparés par décoction. Le décoté total a été testé à 100 et 200 mg/kg et le décocté épuisé à100 mg/kg. Le Sucralfate a été utilisé comme témoin positif à la dose de 1000 mg/kg et le groupe non traité a reçu de l’eau distillée à10 ml/kg. Les extraits ont été administrés par voie intragastrique, une heure après, 0,5 ml d’éthanol à 90% a été administré aux animaux pour provoquer l’ulcère pendant une heure. Après ce temps, les rats ont été sacrifiés. L’estomac de chaque rat a été ouvert pour observer et compter les ulcères. L’indice d’ulcère a été exprimé et le pourcentage de protection a été calculé. A 100mg/kg, le décocté épuisé a induit une protection de la muqueuse de 75%, contre 31% pour le décocté total. Le Sucralfate, utilisé comme témoin a présenté une protection de 87,50%. Ces résultats démontrent que les feuilles de Opilia celtidifolia peuvent intervenir dans le traitement de l’ulcère gastrique. La mise au point d’un phytomédicament contre l’ulcère gastrique à base des feuilles de cette plante est donc envisageable.Mots clés : Opilia celtidifolia, protection, ulcère gastrique

Investigating the impact of contour bunding technology in two agroecologies of southern Mali

Land and water management practices like contour bunding have been implemented by farmers for some time in southern Mali. Farmers use these practices to improve yield performance and increase household income. Datasets on the social, livelihood, and economic benefits of contour bunding technology (CBT) will help to make firm conclusions and recommendations regarding CBT applications in different agroecologies of southern Mali. As part of Africa RISING activities, a survey on CBT was conducted in Africa RISING intervention villages (Bougouni and Koutiala) to facilitate decisions regarding the use and scaling of CBT