Geomatics is a discipline bringing together the practices, methods and technologies that collect, analyze and disseminate geospatial data. Its final objective is the spatial representation of the data collected to identify and demonstrate the results of statistical analyzes. Logically, the term geomatics comes from the contraction of the words geography and computer science. Geomatics specialists agree to distinguish between geomatics oriented Geography and geomatics oriented Computer science. The first contributes to the geolocation of objects and facilitates their spatial analysis, generally on a small scale or in comparative form. Its aim is to define and classify the facts and their various combinations which intervene in the image of a “landscape”. These terms, it is true, have been used in very different senses, according to the scale adopted, according to whether or not the action of men is considered. The second concerns the design and production of Geomatics tools. Geomatics software is produced by this branch of specialists. The geomatics approach is inherently multifaceted and multidisciplinary. It provides access to the three major professional communities concerned with geospatial technologies and their applications :
• acquisition of geolocated data (GPS or equivalent technologies, digital imagery by drone, plane or satellite, LiDAR, etc.);
• transformation of data into meaningful and structured information, and integration into information systems via various computer technologies (GIS, Big data, 3D virtual reality and augmented reality, etc.);
• simulation and spatial analysis of phenomena occurring in the territory (study of urban development, natural or agricultural areas, analysis of road traffic and mobility, establishment of infrastructures, prevention and management of risks, civil security, defense…).

Geo-referencing the territories and opting for new development methods constitute axes of scientific production in the service of development which are at the heart of the redeployments experienced by public policies and which feed the reflections carried out by researchers and experts.
Local development is now at the center of current debates and its paradigm is based on "the capacity of local actors to organize themselves around a project, in other words to unite around a common development objective by mobilizing the potentialities and resources existing in a territory”. (Angeon, Callois, 2007). It is thus assimilated to "a process of diversification and enrichment of economic and social activities in a territory from the mobilization and coordination of its resources and energies» (Deneuil, Laroussi, 2005). Local development therefore reflects the desire to increase the effectiveness of public policies by bringing them closer to the agents concerned, mainly local actors, and tends to reconcile the challenges of institutional, economic, social and cultural development.

To question and position oneself theoretically in relation to this issue and to address the links and interactions established between local development and sociopolitical contexts leading to changes (decentralization, communalization of territories, new reforms, social movements, etc.) as well as between development and territorial dynamics… are all axes of scientific production for the two double issues.

The double volume 07 and 08 of RIGAGER brings together 12 contributions focused on Geomatics, natural resources and the socio-economics development of the intertropical world.

Ndikwé Dourwé et al. analyze the spatial changes that the construction of the hydroelectric dam and mining activities induce. They carry out diachronic mapping through multisource data (2000-2013-2020), land use and assess the degree of environmental pollution. Gabriel Nanfack and Julius Tata Nfor associate the hierarchical multicriteria analysis (AHP) method with Geographic Information Systems (GIS), to arrive at the results according to which the Menoua watershed has a very high and high-risk susceptibility out of about 55.91 km² or 9% of the total area of the basin. Francis Tangmouo Tsoata et al. Map the susceptibility to landslides in Bafoussam (Cameroon). Reni Bibriven Lila models the geophysical risks of landslides using multi-level geospatial data in Southern California. The analysis of the dynamics of land use types in Dizangue from 1975 to 2019 and its impact on the Ossa Lake Wildlife Reserve is carried out by Ghislain Nyembe Etame et al. while Paulin Gotilo et al. present the contribution of the Geographic Information System (GIS) in the hydro-agricultural developments of Batha - East in Chad. In the same vein, Daniele Roseline Bikie evaluates the contribution of GIS in the monitoring of reforestation activities in the ENEF School Forest of Mbalmayo in Cameroon. Valentine Yuninu et al. Based on satellite images and surveys and observations in the field, an inventory of wetland ecosystems in the city of Bamenda in Cameroon in terms of characteristics and services provided to populations. Rabiou Abdou et al. Analyze the farmers' perception of the impacts of tigernuts (Cyperus esculentus L.) cultivation on soil degradation in the department of Aguié in Niger. From field surveys and matrix analysis Florent Gohourou highlights various threats to water resources in the town of San-Pédro in Côte d'Ivoire. Johnson Modika et al., Study the production of palm oil in the sub-prefecture of Mamfe, southwest region (Cameroon) which they consider to be a panacea for rural development. Vincent de Paul Allambademel et al. Present the contribution of microfinance to women's organizations and microfinance for empowerment and local development based on the case study of EXPRESS MIA in N’djamena.

The geospatial analysis taught and practiced must be able to address the vital problems of our society while avoiding the silos and prejudices that make it so difficult to transform the enormous expertise offered by this science. and technical in the field of the environment, regional planning and digital cartography, in force for regional planning and development of the intertropical world.

This part of the African continent has recorded its strongest economic growth in twenty years. The latter is mainly due to strong global demand for commodities and increased investment in these sectors. The exploitation and trade of raw materials is the main source of foreign exchange and tax revenue for many countries in the intertropical zone.