Impacts de la Dynamique des Paysages Agraires sur les Activités Agricoles dans la Commune d’adéane en Basse-Casamance (Sénégal)

La présente étude vise à comprendre la dynamique des paysages agraires et ses impacts sur les activités agricoles dans la commune d’Adéane dans un contexte de dégradation des conditions agro-pédologiques. La cartographie diachronique d’occupation des sols de 1968, 2004 et 2016, réalisée avec Arc Gis (10.2), a permis de quantifier l’évolution spatiotemporelle des paysages agraires. Les mesures in situ effectuées dans les rizières, à l’aide du combo Hanna 87 130 (pH et conductivité électrique) et du réfractomètre, mettent en évidence les phénomènes de salinisation (avec un maximum de 25 %o dans les rizières d’Adéane), et de l’acidification (pH de 4 à d’Agnack-petit), à l’origine de la dégradation des conditions agropédologiques. La principale conséquence est le recul des rizières exploitées (45,45 % pour Adéane et 56,65 % pour Agnack-peti entre 1968-2016) et de la forêt claire (100 % pour Adéane et Agnack-petit entre 1968-2016) au profit de l’arboriculture d’anacardiers qui a progressé de 228,46 % à Adéane et de 519,28 % à Agnack-petit. Face à un développement rapide de l’arboriculture d’anacardier dans la commune d’Adéane et au recul des activités agricoles (riziculture et culture de plateau), il demeure important de s’interroger sur la durabilité des systèmes agricoles dans cette Commune dans un contexte de transition agroécologique. This study aims at understanding the dynamics of agrarian landscapes and their impacts on agricultural activities in the town of Adéane in a context of deteriorating agro-pedological conditions. The diachronic cartography of land use of 1968, 2004 and 2016, carried out with Arc Gis (10.2), made it possible to quantify the spatio-temporal evolution of agrarian landscapes. In situ measurements made in the rice fields, using the Hanna 87 130 combo (pH and electrical conductivity) and the refractometer, highlight salinisation phenomena (with a maximum of 25% o in the Adéane rice paddy fields), and acidification (pH 4 to Agnack-small), causing degradation of agro-pedological conditions. The main consequence is the decline of exploited rice fields (45.45% for Adéane and 56.65% for Agnack-peti between 1968-2016) and light forest (100% for Adéane and Agnack-petit between 1968-2016) benefit of the arboriculture of cashew trees which rose by 228.46% in Adéane and 519.28% in Agnack-petit. In view of the rapid development of cashew growing in the commune of Adéane and the decline of agricultural activities (rice growing and plateau farming), it remains important to question the sustainability of agricultural systems in this Commune in a context of agroecological transition

Tropical Data: Approach and Methodology as Applied to Trachoma Prevalence Surveys

PURPOSE: Population-based prevalence surveys are essential for decision-making on interventions to achieve trachoma elimination as a public health problem. This paper outlines the methodologies of Tropical Data, which supports work to undertake those surveys. METHODS: Tropical Data is a consortium of partners that supports health ministries worldwide to conduct globally standardised prevalence surveys that conform to World Health Organization recommendations. Founding principles are health ministry ownership, partnership and collaboration, and quality assurance and quality control at every step of the survey process. Support covers survey planning, survey design, training, electronic data collection and fieldwork, and data management, analysis and dissemination. Methods are adapted to meet local context and needs. Customisations, operational research and integration of other diseases into routine trachoma surveys have also been supported. RESULTS: Between 29th February 2016 and 24th April 2023, 3373 trachoma surveys across 50 countries have been supported, resulting in 10,818,502 people being examined for trachoma. CONCLUSION: This health ministry-led, standardised approach, with support from the start to the end of the survey process, has helped all trachoma elimination stakeholders to know where interventions are needed, where interventions can be stopped, and when elimination as a public health problem has been achieved. Flexibility to meet specific country contexts, adaptation to changes in global guidance and adjustments in response to user feedback have facilitated innovation in evidence-based methodologies, and supported health ministries to strive for global disease control targets

CONTRAINTES A LA PRODUCTION RIZICOLE ET RECONVERSION SOCIOECONOMIQUE DANS LA COMMUNE DE DIEMBERING (SENEGAL)

International audienceThe purpose of this contribution is to analyze the factors of social conversionfollowing the decadence of rice growing in the municipality of Diembéring. Indeed,this municipality is affected by climatic variability. The resultant salinization and lossof rice land is a real constraint on rice production and, as a result, favors thedevelopment of tourism and fishing activities. Results from the fieldwork(questionary and interview guide) show that rice activities are now threatened bynew activities (tourism and sea fishing). Thus, several farmers have become interested in fishing or are busy with tourism to prevent the precariousness of riceproduction. The mapping of the land use shows globally a spatial recomposition ofthe different classes; formerly agricultural spaces are increasingly occupied by newconstructions.RESUME Le but de cette contribution est d'analyser les facteurs de reconversion sociale suite à la décadence de la riziculture dans la commune de Diembéring. En effet, cette commune est affectée par une variabilité climatique. La salinisation et la perte de terres rizicoles qui en résultent, constituent de véritables contraintes à la production rizicole et favorisent, par conséquent, le développement des activités touristiques et de pêche. Les résultats à l'issu des travaux de terrain (questionnaire et guide d'entretien) montrent que les activités rizicoles sont aujourd'hui menacées par de nouvelles activités (tourisme et pêche maritime). Ainsi, plusieurs paysans se sont intéressés à la pêche ou encore s'activent sur le tourisme afin parer à la précarité des productions rizicoles. La cartographie de l'occupation des sols montre globalement une recomposition spatiale des différentes classes ; les espaces jadis agricoles sont de plus en plus occupés par de nouvelles constructions

CONNEXIONS SOCIOECONOMIQUES ET RECOMPOSITION SPATIALE ENTRE CAP- SKIRRING ET SON HINTERLAND SUITE AU DEVELOPPEMENT DU TOURISME BALNEAIRE

International audienceCette contribution vise à montrer, à travers les résultats obtenus sur la base d'une diversité d'outils d'enquêtes de terrain et d'analyse spatiale, que le processus de mise en place du noyau urbain du Cap-Skirring a parallèlement occasionné de nouvelles formes de connexion et d'interdépendance dans la commune de Diembéring. Il ressort de l'analyse que le début de la crise dans le secteur agricole traditionnel a coïncidé avec l'essor du tourisme balnéaire du Cap-Skirring. Vecteur de reconversion de la population, le tourisme est également le principal facteur d'une nouvelle connexion et recomposition spatiale entre le noyau urbain du Cap-Skirring et son hinterland. La réduction des espaces traditionnellement consacrée aux activités agricoles au profit des infrastructures directement ou indirectement liées au tourisme en est une illustration. Par ailleurs, il se réalise inéluctablement au niveau de cet axe une interdépendance entre Cap-Skirring et les villages environnants suite à son attraction. Le résultat de cette connexion entre la station balnéaire et sa campagne reste un fondement des relations socioéconomiques et de la fusion spatiale sur le tronçon Diembéring-Cabrousse. Les besoins de construction des résidences et autres infrastructures touristiques donnent une nouvelle forme d'extension spatiale du noyau du Cap-Skirring. Abstract This contribution aims to show, through the results obtained by using a variety of field surveys and spatial analysis tools that the setting up process of Cap-Skirting's urban core has, at the same time, caused new forms of connection and interdependence in the rural district of Diembéring. The analysis reveals that the beginning of the crisis in the traditional agricultural sector lined up with the growth of tourism at the seaside resort of Cap-Skirring. As the main factor of populations' redeployment, the tourism is also the main factor for a new connection and spatial conversion between the urban core of Cap-Skirring and its hinterland. The logical follow-up of this situation is the reduction of areas, traditionally devoted to agricultural activities in favor of infrastructure directly or indirectly related to tourism. In addition, the attraction of the Cap-Skirring urban district has inevitably resulted in an interdependence between the town and surrounding villages. 2 The result of this connection between Cap-Skirring seaside resort and its countryside remains a foundation of socioeconomic relations and spatial fusion on the Diembéring-Cabrousse section. The construction needs of residential buildings and other tourist infrastructures give a new form of spatial extension of the core of Cap-Skiring

Inverse Estuaries in West Africa: Evidence of the Rainfall Recovery?

International audienceIn West Africa, as in many other estuaries, enormous volumes of marine water are entering the continent. Fresh water discharge is very low, and it is commonly strongly linked to rainfall level. Some of these estuaries are inverse estuaries. During the Great Sahelian Drought (1968-1993), their hyperhaline feature was exacerbated. This paper aims to describe the evolution of the two main West African inverse estuaries, those of the Saloum River and the Casamance River, since the end of the drought. Water salinity measurements were carried out over three to five years according to the sites in order to document this evolution and to compare data with the historical ones collected during the long dry period at the end of 20 th century. The results show that in both estuaries, the mean water salinity values have markedly decreased since the end of the drought. However, the Saloum estuary remains a totally inverse estuary, while for the Casamance River, the estuarine turbidity maximum (ETM) is the location of the salinity maximum, and it moves according to the seasons from a location 1-10 km downwards from the upstream estuary entry, during the dry season, to a location 40-70 km downwards from this point, during the rainy season. These observations fit with the functioning of the mangrove, the West African mangrove being among the few in the world that are markedly increasing since the beginning of the 1990s and the end of the dry period, as mangrove growth is favored by the relative salinity reduction. Finally, one of the inverse estuary behavior factors is the low fresh water incoming from the continent. The small area of the Casamance and Saloum basins (20,150 Water 2020, 12, 647 2 of 25 and 26,500 km² respectively) is to be compared with the basins of their two main neighbor basins, the Gambia River and the Senegal River, which provide significant fresh water discharge to their estuary

Tropical Data: Approach and Methodology as Applied to Trachoma Prevalence Surveys

Population-based prevalence surveys are essential for decision-making on interventions to achieve trachoma elimination as a public health problem. This paper outlines the methodologies of Tropical Data, which supports work to undertake those surveys. Tropical Data is a consortium of partners that supports health ministries worldwide to conduct globally standardised prevalence surveys that conform to World Health Organization recommendations. Founding principles are health ministry ownership, partnership and collaboration, and quality assurance and quality control at every step of the survey process. Support covers survey planning, survey design, training, electronic data collection and fieldwork, and data management, analysis and dissemination. Methods are adapted to meet local context and needs. Customisations, operational research and integration of other diseases into routine trachoma surveys have also been supported. Between 29 February 2016 and 24 April 2023, 3373 trachoma surveys across 50 countries have been supported, resulting in 10,818,502 people being examined for trachoma. This health ministry-led, standardised approach, with support from the start to the end of the survey process, has helped all trachoma elimination stakeholders to know where interventions are needed, where interventions can be stopped, and when elimination as a public health problem has been achieved. Flexibility to meet specific country contexts, adaptation to changes in global guidance and adjustments in response to user feedback have facilitated innovation in evidence-based methodologies, and supported health ministries to strive for global disease control targets

Tropical Data: Approach and Methodology as Applied to Trachoma Prevalence Surveys

Population-based prevalence surveys are essential for decision-making on interventions to achieve trachoma elimination as a public health problem. This paper outlines the methodologies of Tropical Data, which supports work to undertake those surveys. Tropical Data is a consortium of partners that supports health ministries worldwide to conduct globally standardised prevalence surveys that conform to World Health Organization recommendations. Founding principles are health ministry ownership, partnership and collaboration, and quality assurance and quality control at every step of the survey process. Support covers survey planning, survey design, training, electronic data collection and fieldwork, and data management, analysis and dissemination. Methods are adapted to meet local context and needs. Customisations, operational research and integration of other diseases into routine trachoma surveys have also been supported. Between 29th February 2016 and 24th April 2023, 3373 trachoma surveys across 50 countries have been supported, resulting in 10,818,502 people being examined for trachoma. This health ministry-led, standardised approach, with support from the start to the end of the survey process, has helped all trachoma elimination stakeholders to know where interventions are needed, where interventions can be stopped, and when elimination as a public health problem has been achieved. Flexibility to meet specific country contexts, adaptation to changes in global guidance and adjustments in response to user feedback have facilitated innovation in evidence-based methodologies, and supported health ministries to strive for global disease control targets.</p