Dynamics of nitrogen and phosphorus under the impact of climate change and agricultural land use in the West African Sudan Savannah

Changing climate and agricultural land-use dynamics seriously challenge the future of cropping in the West African Dry Savannah, and, in turn, the livelihoods and food security of rural populations. Current production systems, already vulnerable to soil fertility depletion, are increasingly exposed to rainfall variability and generally to climate change, which, reportedly is expected to increase. Although consent exist that under the “business-as-usual-scenarios” these challenges will exacerbate resource use efficiency and jeopardize the sustainability of the agro-ecosystems, little is predicted about the magnitude of the adverse effects of changing climate on crop responses and hence land use. This obviously hampers the essential development and implementation of both appropriate adaptation measures and policies to increase the resilience of production systems. This study therefore aimed at quantifying and assessing the impact of predicted climate change on growth, yields, and water- and nutrient- use efficiencies of maize-, sorghum-, and cotton-based production systems in the dry savannah of northern Benin. Through a series of farmer- and researcher-managed on-farm trials, data were collected on crop responses to an un-amended soil (no fertilizer application), an integrated soil-crop management practice (recommended fertilizer rates and crop residues retention), a low use of external inputs (i.e. farmers determined the mineral fertilizer rate), and a high rate of mineral fertilizer use. The datasets, collected in 2014 and 2015 at Ouri Yori village in northern Benin, were used to investigate productivity and nutrient use efficiency of three target crops, and to parameterize and evaluate the CERES-Maize, CERES-Sorghum, and CROPGRO-Cotton Cropping System Models. The three crop models were subsequently applied to assess the impact of climate change on responses of maize, sorghum, and cotton to the different soil fertility management practices tested, considering the historical climate (1986-2005) and the ensemble mean of bias-corrected projected climate (2080-2099) from three Global Climate Models for three Representative Concentration Pathways (RCPs 2.6, 4.5, and 8.5). Biomass and economic yields of all three crops responded to both the high use of mineral fertilizer and the integrated soil-crop management practice, but the extent of this response was crop-specific. The highest agronomic efficiencies of nitrogen (N) and phosphorus (P), their apparent recovery as well as the positive partial N and P balances were recorded with the integrated soil-crop management practice, irrespective of the crops. The CERES-Maize model satisfactorily simulated in-season soil moisture and nitrate dynamics, N and P uptake, biomass accumulation, and grain yield. CERES-Maize predicted furthermore a more vigorous crop growth in the projected than in the historical runs, albeit only during the vegetative growth phase. Under the projected climate change, CERES-Maize predicted decreases in water- and N-use efficiencies, N and P uptake, and grain yield, irrespective of the soil fertility management strategies assumed. Similarly, CERES-Sorghum adequately simulated the observed soil water and N dynamics, biomass accumulation, N and P uptake, and the yield of sorghum. It predicted reductions in water- and N- use efficiencies, N and P uptake, and yield across all climate change scenarios and soil fertility management options. CROPGRO-Cotton simulated well soil water dynamics and N uptake during cotton growth, and seed cotton yield. Under the projected climate scenarios, CROPGRO-Cotton predicted increases in water- and N- use efficiencies and yield with the high use of mineral fertilizer or the integrated soil-crop management practice. Cotton responded more efficiently to N applied with integrated soil-crop management practice under future climate scenarios. The increases in productivity will occur, however, at the expense of soil fertility, unless targeted fertilizer management practices are introduced. The overall increase in understanding water- and nutrient- use efficiencies and yields of maize, sorghum, and cotton under both historical and future climate conditions can contribute to updating soil fertility management recommendations for reaching sustainable agricultural production in the Dry Savannah region of West Africa.Einfluss von Klimawandel und Landnutzungsänderungen auf die Stickstoff und Phosphor Dynamik in Anbausystemen der westafrikanischen Trockensavanne Changing climate and agricultural land-use dynamics seriously challenge the future of cropping in the West African Dry Savannah, and, in turn, the livelihoods and food security of rural populations. Current production systems, already vulnerable to soil fertility depletion, are increasingly exposed to rainfall variability and generally to climate change, which, reportedly is expected to increase. Although consent exist that under the “business-as-usual-scenarios” these challenges will exacerbate resource use efficiency and jeopardize the sustainability of the agro-ecosystems, little is predicted about the magnitude of the adverse effects of changing climate on crop responses and hence land use. This obviously hampers the essential development and implementation of both appropriate adaptation measures and policies to increase the resilience of production systems. This study therefore aimed at quantifying and assessing the impact of predicted climate change on growth, yields, and water- and nutrient- use efficiencies of maize-, sorghum-, and cotton-based production systems in the dry savannah of northern Benin. Through a series of farmer- and researcher-managed on-farm trials, data were collected on crop responses to an un-amended soil (no fertilizer application), an integrated soil-crop management practice (recommended fertilizer rates and crop residues retention), a low use of external inputs (i.e. farmers determined the mineral fertilizer rate), and a high rate of mineral fertilizer use. The datasets, collected in 2014 and 2015 at Ouri Yori village in northern Benin, were used to investigate productivity and nutrient use efficiency of three target crops, and to parameterize and evaluate the CERES-Maize, CERES-Sorghum, and CROPGRO-Cotton Cropping System Models. The three crop models were subsequently applied to assess the impact of climate change on responses of maize, sorghum, and cotton to the different soil fertility management practices tested, considering the historical climate (1986-2005) and the ensemble mean of bias-corrected projected climate (2080-2099) from three Global Climate Models for three Representative Concentration Pathways (RCPs 2.6, 4.5, and 8.5). Biomass and economic yields of all three crops responded to both the high use of mineral fertilizer and the integrated soil-crop management practice, but the extent of this response was crop-specific. The highest agronomic efficiencies of nitrogen (N) and phosphorus (P), their apparent recovery as well as the positive partial N and P balances were recorded with the integrated soil-crop management practice, irrespective of the crops. The CERES-Maize model satisfactorily simulated in-season soil moisture and nitrate dynamics, N and P uptake, biomass accumulation, and grain yield. CERES-Maize predicted furthermore a more vigorous crop growth in the projected than in the historical runs, albeit only during the vegetative growth phase. Under the projected climate change, CERES-Maize predicted decreases in water- and N-use efficiencies, N and P uptake, and grain yield, irrespective of the soil fertility management strategies assumed. Similarly, CERES-Sorghum adequately simulated the observed soil water and N dynamics, biomass accumulation, N and P uptake, and the yield of sorghum. It predicted reductions in water- and N- use efficiencies, N and P uptake, and yield across all climate change scenarios and soil fertility management options. CROPGRO-Cotton simulated well soil water dynamics and N uptake during cotton growth, and seed cotton yield. Under the projected climate scenarios, CROPGRO-Cotton predicted increases in water- and N- use efficiencies and yield with the high use of mineral fertilizer or the integrated soil-crop management practice. Cotton responded more efficiently to N applied with integrated soil-crop management practice under future climate scenarios. The increases in productivity will occur, however, at the expense of soil fertility, unless targeted fertilizer management practices are introduced. The overall increase in understanding water- and nutrient- use efficiencies and yields of maize, sorghum, and cotton under both historical and future climate conditions can contribute to updating soil fertility management recommendations for reaching sustainable agricultural production in the Dry Savannah region of West Africa

Analyse Du Rebut Des Cliches Radiographiques Dans Le Service De Radiologie Et Imagerie Médicale Du Chu Campus De Lomé Au Togo

Purpose: To analyze the waste factors of rejected X-rays films. Methodology: Descriptive and analytical prospective study from 1 January to 30 June 2017 carried out in the department of radiology and medical imaging of the Campus University Hospital of Lomé in Togo. Results: 4912 patients had received 5630 radiographic incidences, including 3288 (58.4%) on the analogy and 2342 (41.5%) on the digital. The reject rate was 12.5%. The vast majority of the X-rays films, 682 (96.9%) were rejected by the radiographers themselves just after development. The resumption frequency ranged from one repeat (550 X-rays films, or 78%) to 4 repeats (8 X-rays films, or 1%). Almost all of the rejected films, 702 (99.7%) came from the analogical room. Chest X-ray was the incidence with more rejection in 33.9% followed by pelvic and lower limb incidences in 21% of cases. More than 2/3 of the rejected films, 473 (67.2%), came from the students' act. The causes of the rejection were mainly centering (25.5%), underexposure (20.17%) and overexposure (12.93). The financial loss caused by the scrap of X-rays films amounted to about 418800F CFA or 638.5 €. Conclusion: Strengthening communication between radiographers and radiologists is necessary to avoid unnecessary repeats of patient’s radiographs

Maladie de Haglund: à propos de trois cas

La maladie de Haglund est une pathologie relativement sous évaluée. Elle est liée à un conflit calcanéo-achilléen. Nous rapportons les cas de patients âgés de 40, 42 et 37 ans, révélés par des oedèmes douloureux  de la cheville. Le diagnostic a été confirmé à la radiographie standard de la cheville en charge et à l'échographie chez tous les patients. Un seul patient avait bénéficié d'une exploration  IRM. Le traitement, initialement médical dans tous les cas, s'est soldé par une chirurgie de résection de l'angle postéro-supérieur du  calcanéum chez un patient. L'évolution a été favorable chez tous les patients.Key words: Maladie de Haglund, écho-Doppler, radiographie, IRM, Afriqu

Influence de la taille et dea la saison de pêche sur les qualités organoleptiques des palourdes de l'atlantique (spisula solidissima) et la volonté à payer du consommateur

Dans un marché de libre concurrence, certains paramètres tels que la saison de pêche et la taille des produits halieutiques ont une très grande importance sur la fixation des prix et la volonté à payer du consommateur. Afin de valider ces données, des échantillons de palourdes de l'Atlantique (Spisula solidissima), pêchés dans la zone 4T du Fleuve Saint-Laurent durant trois périodes différentes de l'année, ont été repartis en quatre classes de taille et soumis après cuisson aux membres d'un Jury semi - entraîné pour des tests d'évaluation organoleptique. La tendreté et la saveur des palourdes de taille petite et moyenne ont été préférées a celle de taille plus grande. De plus les échantillons d'été et d'automne sont meilleurs au goût que ceux de printemps. Alors que la période de pêche et la taille des individus n'ont pas d'influence significative sur la composition proximale (teneur en humidité, protéine et lipides), la composition en acides aminés libres responsables de la saveur des produits marins varie de façon significative entre les parties anatomiques de la palourde. Quant a la volonté a payer du consommateur, elle est beaucoup moins forte pour les palourdes de printemps et celles de plus grande taille.Keywords: Clams, Size, Demand, Willingness-to-pay, Consumers, Flavou

ETIOLOGIES DES PLEURESIES DU SUJET AGE AU TOGO

Objective: The aim of this study was to review the current aetiologic profile of pleurisies in the elderly people. Materials and method: We carried out a retrospective study based on the data of 126 patients, old of at least 55 years, hospitalised from January 2007 to December 2011 for pleurisy in the pneumology department of Sylvanus Olympio teaching hospital of Lome. Results: Pleurisies represent 23,11 % of elderly people’s hospitalisation motives. The Sex-ratio was 1 and the average age of the patients 65 ± 09 years old. The clinical aspect was dominated by thoracic pain (88,88 %) and cough (69,84 %). The chest X-ray revealed pleural effusion at the left side in 48,41 %, at right side in 46,83% and of medium abundance in 57,93 %. The liquid was citrine in 53,97 %, haematic in 30,95% and purulent in 15,08% . Pleurisies were of cancerous origin in 32,54 %, tubercular in 17,46 % and bacterial not tubercular in 14,58%. No aetiology had been found in 33,33 %. The mortality was 27,78 % and due to cancers and idiopathic pleurisies in 86 % during three months’ follow up. Conclusion: Cancers are the first aetiology of pleurisies followed by tuberculosis in elderly people. The acquisition of the new means of pleural exploration is important to reduce the proportion of idiopathic pleurisies

ETIOLOGIES DES PLEURESIES DU SUJET AGE AU TOGO

Objective: The aim of this study was to review the current aetiologic profile of pleurisies in the elderly people. Materials and method: We carried out a retrospective study based on the data of 126 patients, old of at least 55 years, hospitalised from January 2007 to December 2011 for pleurisy in the pneumology department of Sylvanus Olympio teaching hospital of Lome. Results: Pleurisies represent 23,11 % of elderly people’s hospitalisation motives. The Sex-ratio was 1 and the average age of the patients 65 ± 09 years old. The clinical aspect was dominated by thoracic pain (88,88 %) and cough (69,84 %). The chest X-ray revealed pleural effusion at the left side in 48,41 %, at right side in 46,83% and of medium abundance in 57,93 %. The liquid was citrine in 53,97 %, haematic in 30,95% and purulent in 15,08% . Pleurisies were of cancerous origin in 32,54 %, tubercular in 17,46 % and bacterial not tubercular in 14,58%. No aetiology had been found in 33,33 %. The mortality was 27,78 % and due to cancers and idiopathic pleurisies in 86 % during three months’ follow up. Conclusion: Cancers are the first aetiology of pleurisies followed by tuberculosis in elderly people. The acquisition of the new means of pleural exploration is important to reduce the proportion of idiopathic pleurisies

Design and installation of a platform for real-time ultrasound tele expertise and delayed ultrasound tele-diagnosis at UHC of Lome to serve the peripheral health centers

Introduction : La télémédecine en général et la télé échographie en particulier est une des solutions indéniables au problème de pénurie de médecins spécialistes notamment dans les pays en développement au regard des progrès sans cesse croissant des nouvelles technologies de I‘information et de la communication. Objectif : Concevoir et valider un système de télé expertise échographique temps réel et de télédiagnostic échographique temps différé entre sites expert (CHU) et isolé (hôpitaux périphériques) avec une infrastructure moindre coût accessible même aux pays à faible environnement numérique comme le Togo. Matériels et Méthodes : Une technologie innovante de télétransmission (vidéos échographiques et d’ambiance) temps réel via internet à base de Caméra réseau AXIS 207 et de Serveur vidéo internet AXIS 243 dotée d’adresse IP ou un logiciel d’accès à distance (LogMeln) permet une télé expertise temps réel si le centre isolé dispose d’un échographiste peu expérimenté.Introduction: Telemedicine generally, and telesonography in particular, is one of undeniable solutions to the problem of specialists’ shortage specially in developing countries with regard to the progress ceaselessly growing of the new technologies of information and communication. Purpose: Design and validate a .system of real time ultrasound tele-expertise, and delayed ultrasound tele-diagnostic between isolated peripherals hospitals and University Hospital center (Expert center) functioning with a lesser infrastructure cost accessible to low digital environment countries like Togo. Materials and Methods: An IP camera and an internet video server are installed in a geographically isolated site equipped with an echograph served by an echographist of first level. Real time tele-expertise (second opinion diagnosis) is possible via internet with an expert center

Spatial and temporal variation in precipitation in Togo

Precipitation is one of the important variables in hydrological cycle and has important application in both irrigated and rainfed agricultural crop production. Better understanding of spatio-temporal variability of precipitation across Togo is important and useful for water users and most agricultural activities. Thus, the objective this study was to analyze the spatial and temporal variation in monthly and annual precipitation across Togo for the period of 1961-2001. Monthly precipitation data was provided by the national direction of meteorology. The performed analysis revealed a decline in annual total precipitation across almost all agro-ecological zones in Togo with the Maritime Region revealed as the driest. Kouma-Konda received the greatest 40 year average annual precipitation in the country with 1714mm. June was the wettest month across Togo. The greatest coefficient of variation (82%) in monthly precipitation was registered in January for the study period. Water management implications could be generated from this study, especially for rural and urban agricultural production zones. Mann Kendall’s test was used to understand the temporal variation in precipitation over the period of 40 years. Decreasing trends in annual precipitation are likely to have significant impacts across Togo, where rainfed agriculture is widely practiced. On the other hand, persistent and progressive precipitation deficits are likely to cause recurrent drought and destroy plant cover, increase evapotranspiration, increase surface albedo and, affect other aspects of the water and energy balance