Integrating both modeling approach and stakeholders’ perspectives to derive past and future trends of land use land cover (LULC) is a key to creating more realistic results on LULC change trajectories and can lead to the implementation of appropriate management measures. This article assessed the past changes of LULC in the Mono River catchment using Landsat images from the years 1986, 2000, 2010, and 2020 by performing Machine Learning Classification Method Random Forest (RF) technique, and using Markov chain method and stakeholder’s perspective to simulate future LULC changes for the years 2030 and 2050. LULC was classified as savanna, cropland, forest, water bodies, and settlement. The results showed that croplands and forests areas declined from 2020 to 2050 with decreases of −7.8% and −1.9%, respectively, a modest increase in settlement (1.3%), and savanna was the dominant LULC in the study region with an increase of 8.5%. From stakeholders’ perspective, rapid population growth, deforestation, rainfall variability/flood, urbanization, and agricultural expansion were the most important drivers associated with the observed LULC changes in the area. Other factors, such as lack of political commitment, distance to river, and elevation were also mentioned. Additionally, most the land-use scenarios identified by stakeholders would intensify land degradation and reduce ecosystem services in the area. By considering all of these potential LULC changes, decision-makers need to develop and implement appropriate solutions (e.g., land use planning strategies, reforestation campaigns, forest protection measures) in order to limit the negative effects of future LULC changes.

Recurrent floods have become a major problem in the transboundary Lower Mono River catchment of Togo and Benin, causing more damage and loss of life than any other disaster in the area. The level of understanding about floods and their management can be as diverse as the groups within the communities and thus can present a variety of perspectives. People tend to perceive flood risk and management differently due to their proximity to flood-prone areas and their level of vulnerability as well as their capacity to adapt. Therefore, this study explores the specific perspectives of local communities and experts on floods in the transboundary Mono catchment, which can help to inform better adaptation strategies according to the contexts of each community. We conducted series of focus groups discussions (FGDs) using the Actors, Resources, Dynamics, and Interactions (ARDI) framework to develop mental models of flood management. This approach allowed us to identify the causes and impact of flooding in the area, and to describe the actors and effects of flood events on the main natural resources as well as the dynamics and interactions that drive change and influence flood management in the study area. The results indicate that the perceptions of local communities and experts show both similarities and differences. These differences include (1) perceptions of relevant direct actors, (2) perceptions of resources at stake, and (3) actor-specific resource utilization. Considering these dissimilar views between expert and local community knowledge systems appears to be an important contributing factor to improving flood mitigation efforts in the catchment. Adapting risk communication and measures taken for flood management in accordance with the perceptions of affected communities could greatly increase success, with positive long-term effects for the involved institutions and communities regarding mutual trust-building.

Le permafrost et ses modifications dans les parois rocheuses de haute montagne restent insuffisamment compris, en particulier du fait de la rareté des sites instrumentés. D 'où l 'intérêt de développer des recherches à l 'Aiguille du Midi (3842 m), aux expositions et pentes variées, et dont les parois et galeries sont accessibles toute l 'année. Dans le cadre du projet PermaNET, nous y suivons le régime thermique dans la roche, (i) avec 9 capteurs à un ou trois thermistors implantés jusqu 'à 55 cm de profondeur ; (ii) par tomographic électrique résistive, sur la base de la relation température/résistivité du granite local ; (iii) par thermographie infrarouge sur les parois. Ces mesures sont complétées par deux stations météo automatiques mobiles, tandis qu 'il est prévu l 'installation de chaînes de thermistors d'une dizaine de mètres de profondeur. Ces données seront utilisées pour valider des modèles physiques ou construire des modèles statistiques de la distribution de la température de la roche et sa variabilité. Par ailleurs, un MNT à haute résolution réalisé à l 'aide de laserscans terrestres longue et courte portées (pour les parois et dans les galeries respectivement) servira de support à la modélisation numérique (i) de la fracturation de la roche et de la circulation d'eau dans les fractures non saturées ; (ii) de la distribution 3D et de l 'évolution des températures de subsurface. Enfin, le suivi de la face SE de l 'Arête des Cosmiques et du Pilastre SE à l 'aide d 'un laserscan terrestre longue portée complète des datations cosmogéniques sur certaines parois pour documenter la morphodynamique passée et actuelle du site.