Les zones territoriales de l’Arc Cuprifère Katangais sont parmi les principaux réceptacles d’une forte concentration démographique et des sites miniers en RD Congo. Par conséquent, les paysages naturels y subissent des profondes mutations dans leur structure spatiale. Cette étude caractérise les changements de l’occupation du sol avant et après la libéralisation du secteur minier en 2002. Trois mosaïques d’images Landsat (TM 1990, ETM + 2002 et OLI 2015) ont été classifiées en "Forêt" et "Non Forêt ", et validées par les valeurs du coefficient Kappa. Les résultats ont montré une perturbation grandissante du paysage, notamment après la libéralisation du secteur minier. La matrice paysagère, initialement constituée des taches de « Forêt » s’est dégradée et/ou convertie en classe « Non Forêt ». Une suppression et une dissection des taches de forêt en opposition à la création de taches de "Non Forêt" ont été identifiées comme des processus de transformation spatiale. La dynamique régressive des écosystèmes forestiers résultant de plusieurs activités anthropiques dont l’agriculture, la production du bois énergie et activités minières exécutés en synergie, a été plus poussée dans la zone de Kasenga. Les administrateurs territoriaux devront en urgence déclarer des zones protégées et créer des réserves naturelles pour préserver les écosystèmes forestiers.
The uncontrolled logging of Pterocarpus tinctorius Welw. in the Kasenga territory in the southeast of the Democratic Republic of the Congo is of significant socioeconomic benefit, but above all, it is a threat to the stability of forest ecosystems. Based on Landsat images from 2009, 2013, 2017 and 2021, the landscape dynamics of the Kasomeno region in the Kasenga territory, a P. tinctorius exploitation area, was quantified using a mapping approach coupled with landscape ecology analysis tools. The results reveal a continuous loss of forest cover over all the periods studied, mostly between 2013 and 2017, primarily through the dissection of patches. Also, through the spatial process of attrition, the fields recorded a regressive dynamic between 2013–2017, a sign of abandonment of agricultural activity in favour of P. tinctorius illegal logging. These landscape dynamics are the consequences of strong anthropic activities in the study area, leading to an important spatial expansion of the savannah. Consequently, the level of landscape disturbance doubled from 0.8 to 1.7 between 2009 and 2021. Our results suggest that, without regulatory enforcement, illegal logging of P. tinctorius seriously compromises forest ecosystem health and household food security in the region.
An accurate description of spatial urban growth is a prerequisite step in order to implement appropriated policies to improve the ecosystem service performance of green spaces in a city. Such information is, however, absent in Lubumbashi, the second metropolis of the Democratic Republic of Congo, despite its high demographic growth rate and an unplanned spatial urban growth. This study was designed to characterize the spatial pattern of green spaces and the extent of changes driven by the urbanization along the urban-rural gradient using a combination of landscape metrics and floristic plots. Our results revealed that the number of patches was directly proportional to the degree of urbanization of the city, whereas the area of the green spaces and the index of the largest patch showed an inverse relationship with the urbanization degree. Urban green spaces were dominated by attached and roadside spaces that are more equipped and present a higher occurrence of cultivated plants. By contrast, peri-urban green spaces were characterized by buffer zones, fields, abandoned areas, and informal spaces, with an elevated proportion of invasive species and natural vegetation. Moreover, it was found that the number of exotic species increased with the degree of urbanization, reaching values considered a threat to the indigenous flora. The current results underline the need for urgent measures oriented both toward increasing the spatial connectivity between green spaces (e.g., by creating new green spaces planted with indigenous species) while reducing the spread of invasive species in the city.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.