The study examines possible solutions to restore the River Nyong’s wetlands, Mbalmayo, Cameroon through Nature-based solutions (NbS) using Tchouaffé’s Theory of change (TToC). TToC is a new educational model to assess performance of network of actors co-working to overcome socio-environmental challenges. Many study from the same authors, to find innovative approaches and solutions to challenging wetlands stated that the major challenges or causes of the degradation of the river Nyong were mostly: Deforestation; recurrent pollutions and sedimentation of the river bed and the associated consequences are: The growth of floating macrophytes or eutrophication, which in turn induces a gradual reduction in the flow of the river and unprecedented damage to its ecosystem as well. So the main objective of this study consists of diagnosing the root causes of the eutrophication and to prescribe solutions to remediate them. To reach this aim we carried out geo-referencing of one of the critical zones of river Nyong and we also carried out focus group discussions to collect information from 50 riperian populations. As key findings 48 out of 50 interviewed respond and 60

Les catastrophes d’inondations constituent de nos jours, l’un des problèmes majeurs auquel fait face l’humanité toute entière. C’est dans cette perspective que s’inscrit cet article sur la simulation d’une crue centennale pour la cartographie des zones de dangers d’inondations dans le sous bassin versant du Mayo Tsanaga (Extrême-nord, Cameroun). L’objectif de la présente étude est de cartographier les zones de dangers d’inondations à partir des résultats de la simulation d’une crue centennale. Une méthodologie basée sur l’analyse des séries pluviométriques (1982-2023), couplée aux analyses des images satellites (Alos Palsar DEM de 10 m de résolution, Airbus, Bing Satellite), nous a permis d’atteindre les résultats escomptés. Les principaux résultats montrent des vitesses d’écoulement comprises entre 0 et au-delà de 7,64 m/s, des hauteurs et des profondeurs d’eau parfois supérieures à 4 m, selon les endroits, dans la zone étudiée. La combinaison des hauteurs d’eau et des vitesses d’écoulement dans le sous bassin versant du Mayo Tsanaga, a permis de cartographier les zones de dangers d’intensité forte (1663 maisons) ; moyenne (1704 maisons) et faible (2551 maisons). Les recommandations suisses relatives à la gestion optimale des zones inondables précisent que les zones à forte intensité doivent être classées comme zones d’interdiction de construire, celles à intensité moyenne comme zones réglementées, et celles à faible intensité comme zones de sensibilisation. Les conclusions auxquelles nous sommes parvenues constituent, sans nul doute, un véritable outil d’aide à la décision visant à améliorer le cadre et les conditions de vie des populations résidant dans les zones à risque d’inondations dans le sous bassin versant du Mayo Tsanag

In Africa, bushfires are common practices in savannah regions. Their impact, is the subject of many scientific debates. The protected areas, of North Cameroon are subjected to ambivalent effects of these fires. Using high-resolution remote sensing data, this work aims at assessing burned areas at the interannual and intraannual scale in order to explain the complex environmental dynamics of landscapes, to contribute to fire management in a context of protected areas. To achieve this, time series of sentinel-2 images from the Multi Spectral Instrument from the year 2015-2020 have been used. By the unitemporal and multitemporal methods, the development of spectral indices has made it possible to locate the burned surfaces and to determine the periods of the fires. Observations and field surveys aimed to understand the factors of fires using, their typology as well as the roles of the actors. The findings show that each spectral index has its own ability to detect burnt surfaces: The NDVI can detect fires only at the start of the dry season, the SAVI is suitable for identifying intermediate and late fires, while the NBR is best suited for separating burnt and unburnt surfaces throughout the season, regardless of the method employed. Depending on their periods of occurrence, the fires spread more in parks with a fairly extensive grass cover compared to overexploited ordinary areas. They then depend on socio-environmental factors, namely the state of land used, the continuity of the herbaceous cover and the social practices in place. The mapping and monitoring of burned surfaces by remote sensing therefore constitute a tool and a method for diagnosing the state of the herbaceous plant cover and for managing natural resources.

The design of decision-support systems remains a challenge because no method has yet been approved, although several approaches have been proposed. Multidimensional Canonical Partitioning (MCP) is a supply-driven approach to design decision-support systems, previously proposed. In this approach, decision systems are designed from Entity/Relationship (E/R) schema. The schema provided as input is reduced to a flat relation, if it is not already the case, by using universal relations assumption. The design approach uses two main algorithms. The first is a greedy type heuristic algorithm, and the second a matching algorithm. The approach has six steps. In this paper, we implement algorithms used in the design approach. We then propose a graphical interface as a tool for implementing the approach. The tool, called PaCaM, is intended to be used by decision-support systems designers. We after all apply the design approach on urban transactional systems.

In order to have reliable information on the extent of forest degradation and deforestation for adequate decision-making, the spatial and temporal dynamics of the protected area, Missahohe Classified Forest, were studied from Landsat imagery for the years 1986, 2001 and 2018.A diachronic analysis of the land cover (between 1986 and 2001, on the one hand, and 1986 and 2018 on the other hand) was carried out to analyze ecosystems dynamics.The drivers of forest degradation and deforestation linked to the anthropogenic pressure observed following the invasion of the protected area in the 1990s have been identified.A supervised classification was carried out by applying the "maximum likelihood" algorithm under the ENVI 5.1 software.The overall accuracy of the resulted maps measured from the Kappa index vary from 0.8 to 0.87.The conversions experienced by the different units of land use were analyzed.This analysis shows that forest strata decreased from 1432 ha to 1221.57ha between 1986 and 2018, a loss of about 210 ha, particularly to crops and human settlements that did not exist in 1986.Riparian forests and dense forests are the forest strata that have experienced more regression over the past three decades (from 28.73% in 1986 to 3% in 2018 and from 24.63% in 1986 to 22% in 2018 respectively).While the annual rate of deforestation is estimated at 0.5%.Agriculture, logging, carbonization and honey harvesting are the four main factors of vegetation cover alteration in the study area.All of these results are necessary for the choice of the appropriate protection strategy option for the protected area.

Various information systems have been developed for decision support. But, they rely essentially on transactional methods. From data and transactional databases, we proposed a supply-driven approach to design data warehouses. The approach takes as input, a universal relation, applies vertical partitioning by a greedy type heuristic algorithm. Partitions obtained are transformed into dimensions using a matching algorithm. The other elements of the multidimensional annotation are deduced by guidelines, and the data warehouse schema is generated using a multidimensional conceptual pattern. The transformation of those transactional systems into decision support ones aims at facilitating the storage, exploitation and the representation of data using new databases generation technologies.

Le nord du Cameroun est, avec les monts Mandara, une référence en Afrique en matière d'aménagement en terrasses. Ces réseaux de terrasses en gradins isohypses, qui cisèlent l'intégralité des pentes et infiltrent toutes les pluies, se voient complétés, généralement dans les talwegs plus menacés par l'érosion, par des dispositifs de canaux-drains souvent dédiés à des cultures particulières attirées par l'eau. Dans les plaines du Diamaré, ce n'est plus l'entièreté du terroir qui, comme en montagne, suit un modèle cohérent d'aménagement. Les techniques antiérosives n'intéressent que certaines parties des terroirs. Il s'agit des vertisols, voués à une culture stratégique en ce qu'elle est réputée prévisible, celle des sorghos repiqués de contre-saison dont la part dans l'agrosystème n'a cessé de croître depuis les années 1950. Ces stratégies de lutte contre l'érosion et l'entretien de la fertilité, en dépit de leur degré de sophistication et de leur efficacité par le passé, ont perdu de leur pertinence avec les mutations démographiques, sociales et techniques. Aujourd'hui, la lutte antiérosive est devenue un impératif pour l'ensemble des communautés agricoles et pastorales du nord du Cameroun, mais les recettes proposées par les agents du développement n'ont pas jusqu'ici entraîné l'adhésion attendue.

Background: Health situation in Chad, particularly in the Western Logone is characterized by a general high morbidity, a difficult access to healthcare structures, and by a plurality of healthcare provision. In the evnt of illnesses, very few patients (18%) resort to modern healthcare. Objective: This study aims at adressing the link between the provision of healthcare system, geographical accessibility and patients therapeutic behaviors . Methods: We have resorted to methodology usually used in in geography that is review literature, surveys and interviews. Over the 429 investigated households, a response rate of 99.9% was obtained.. Levels of analyses include both descriptive and explanatory analyses. Results: 96% of the investigated individuals live close to a health center (0 to 10 kms) is. Conversely, 75% are attending healthcare centers located beyond 10 kms. In the event of illnesses, about 82% of patients resort firstly to traditional care

Les auteurs de cet article évaluent la contribution des diplômés des parcours sciences et techniques de l’Université de Ngaoundéré au développement du Nord-Cameroun. Pour ce faire, une enquête par questionnaire a été effectuée auprès de ses diplômés ayant un emploi. La technique de contact par boule de neige a permis d’en enquêter 360 à Douala, Yaoundé et les principales villes du Nord-Cameroun. L’analyse des données collectées a été faite par des méthodes de statistiques descriptives. Les résultats montrent que l’Université de Ngaoundéré a contribué non seulement à la formation des ressources humaines de cette région, mais a également entrainé une modification du tissu économique et une diversification du marché de l’emploi même si cet impact reste bien faible sur les secteurs pouvant propulser le développement.

La transition formation-emploi est une etape importante dans la vie d’un diplome. L’objectif principal d’une formation universitaire est l’insertion sur le marche de l’emploi. La periode qui se situe entre la fin des etudes et le debut d’une carriere professionnelle est souvent tres difficile a surmonter. L’universite de Ngaoundere a l’instar des autres universites du Cameroun met sur le marche de l’emploi chaque annee des diplomes aussi bien dans les filieres de Lettres et Sciences Humaines que des filieres scientifiques et technologique Pendant ce temps, le marche de l’emploi est de plus en sature et les conditions d’entree sont de plus en plus difficile. C’est fort de constat que cette contribution vise a analyser la transition formation-emploi au sein des diplomes en sciences sociales et humaines de l’universite de Ngaoundere. Les donnees ont ete obtenues a travers des enquetes de terrain dans les principales villes du Nord-Cameroun et celles de Douala et de Yaounde. Les donnees ont ete analysees par des methodes statistiques (analyse descriptive et analyse en composante principale) integree dans le programme SPSS. Les resultats issus des analyses ont permis de montrer que la situation professionnelle des diplomes evolue progressivement vers l’obtention d’un emploi au fur et mesure que les annees passent.

Legislation for human and animal migrations in Central Africa: the case of Cameroon, the Central African Republic (CAR) and Chad. Migrations are central to development issues in Central Africa because of the population increase and the dire economic situation. The states in the region have attempted to legislate with this in mind. The aim of this study is to analyse the role of the legislative texts on migrations and compare it to the reality in the field after conducting an inventory. The methodology adopted is based on field surveys and research on existing texts in Cameroon, CAR and Chad, combined with an analysis. The findings show that many legal texts have been issued to regulate the movements of people and animals. In Cameroon, for example, the presidential decree no. 73/59 of 9 th

The contribution made by geomatics to village land management in the savannas of Central Africa. Over the past few decades, the savannas of Central Africa have undergone major demographic, social, territorial and environmental changes. These changes have left their mark on space, thus posing the problem of territorial management in most regions. This paper aims to show how geomatics can help in the analysis of village land dynamics with a view to understanding the processes and to help decision-making. The concept of territory was defined before being applied to the geographic research, which was conducted in a set of rural territories representative of the dynamics of the savanna in Cameroon, the Central African Republic and Chad. The data used were obtained from topographic maps, satellite images, GPS field surveys and socio-economic surveys. The geo- referenced data were processed using an organised set of geomatic tools and materials. The statistical and cartographic results can be applied to archiving spatio-temporal data, as well as to the understanding of the area's historical evolution and to forecast analysis, which is useful for decision-making. However, geomatics are dependent on human resources and logistics.

Résumé — Situées en Afrique centrale et au Centre du Cameroun, les Hautes Terres de l'Adamaoua sont la zone de transition entre le nord soudano-sahélien et le sud forestier. Elles s'étirent sur environ 400 km entre le Nigeria et la République centrafricaine et culminent à 2 460 m d'altitude au sommet des Tchabal Mbabo. Cette communication, à partir de l'analyse des images satellitaires, des enquêtes et des observations de terrain, retrace les processus et les causes socio-économiques des crises environnementales en cours dans cette région. Il en ressort que l'imbroglio foncier national, le surpâturage lié au problème foncier et à la pseudo modernisation de cette activité, les conflits d'exploitation et de gestion des ressources naturelles sont responsables d'une transformation rapide du couvert végétal et des sols. Des mesures renforcées pour une exploitation durable des ressources en végétation et en sol s'imposent. Abstract — From socio-economic crises to environmental crises in the Adamawa Highlands (Cameroon). The Adamawa Highlands in Central Africa and central Cameroon constitute the transitional zone between the soudano- Sahelian North and the forested South. They extend across some 400 km between Nigeria and the Republic of Central Africa, reaching a peak of 2 460 m at the summit of the Tchabal Mbabo. This paper analyses satellite images, surveys and field observations to retrace the socio-economic causes and processes of the environmental crises currently affecting the region. The findings show that the extremely confused national land situation, the overgrazing linked to the problem of land and its pseudo-modernisation, the conflicts of use and management of natural resources are responsible for the rapid transformation of plant cover and soils. Stronger measures for the sustainable use of plant resources and soil are essential.