Most landscape cover assessments for conservation programmes rely largely on remote sensing analyses. These analyses, however, neglect how people inhabiting protected zones perceive and structure land cover. Using socio-ecological systems (SES) analysis in a forest-savannah mosaic on the Congo Basin forest edge (Democratic Republic of Congo), we investigated how human practices, landscape perceptions and land use patterns affected forest cover. We conducted remote sensing analysis using a Sentinel-2 satellite image and 187 GPS landmarks, producing a land cover map with 11 classes. Our results yielded an 81.85% correspondence with additional 164 GPS landmarks, a robust score in tropical areas. We conducted 40 individual interviews, eighteen focus group discussion workshops and nine months of participant observation of human practices to identify 19 land units and elaborate a granular SES system structuring the landscape. Integrating local knowledge and practices with general ecological and agronomic processes, we developed a landscape dynamics model revealing progressive forest colonisation of savannahs. Our methods demonstrate that a forest-edge landscape cover evaluation through remote sensing and local knowledge can contribute to finer-grained assessment of land cover and ecosystem services. This assessment can assist conservation efforts by considering local populations' practices on and perceptions of landscape change. Résumé La plupart des études de couverture terrestre effectuées dans le cadre de programmes de conservation s'appuient en grande partie sur des analyses basées sur la télédétection. Cependant, ces analyses négligent la façon dont les populations habitant dans les zones protégées perçoivent et structurent la couverture terrestre. À l'aide d'analyses portant sur les systèmes socio-écologiques (SEE) effectuées dans une mosaïque de forêts et de savanes située à la lisière de la forêt du Bassin du Congo (République démocratique du Congo), nous avons étudié la façon dont les pratiques humaines, la perception de la couverture terrestre et la structure de l'utilisation des terres affectait la couverture forestière. Nous avons réalisé une analyse basée sur la télédétection en utilisant une image satellite Sentinel 2 et 187 repères GPS pour produire une carte de la couverture terrestre contenant 11 catégories. Nos résultats ont montré une correspondance de 81.85% avec 164 repères GPS supplémentaires, | 693 DEMICHELIS Et aL.

Along the edges of the Congo basin forest, where forest-savannah mosaics are the main ecological formation, it is important to determine how this mosaic has developed, particularly for forest protection. Have savannah lands resulted from deforestation or have forest patches expanded into them? Given the long-standing human occupation of this region, this question needs to be addressed through human-environment relationships over time. Combining oral histories of village mobility and geographical analyses of a forest-savannah mosaic in the Bolobo territory (Democratic Republic of Congo) can shed light on the landscape dynamics. This study involved nine months of daily participant observations of human land use practices, 40 individual interviews and 18 focus groups to analyse changing village mobility from the late 19th century to the present. Several maps were produced by combining oral histories of past village mobility with an evaluation of 44 GPS landmarks corresponding to former villages. Two Principal Component Analyses (PCA), based on landscape composition within a 250 m-radius buffer zone around the GPS landmarks, according to a land cover map classifying the landscape into 11 categories, were used to document forest expansion into old abandoned villages and the effect of distance from currently inhabited villages. Forest cover expanded into the abandoned villages and the savannah as a consequence of environmental eutrophication facilitating forest establishment. Forest use decreases with distance from currently inhabited villages as a result of a shift from semi-sedentary livelihoods in small settlements to entirely sedentary livelihoods in larger, extended villages. Livelihood transformations that took place during and after colonisation resulted in a decline in the quality of environmental goods and reduced the well-being of human populations. These insights can help NGO conservation and development efforts to be more sensitive to overlooked local human practices and needs.

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Studies of landscape dynamics in protected areas often rely exclusively on remotely-sensed data, leading to bias by neglecting how local inhabitants, who often have a long history of interaction with their environment, perceive and structure the landscape over time. Using a socio-ecological system (SES) approach in a forest-swamp-savannah mosaic within the Bas-Ogooué Ramsar site in Gabon, we assess how human populations participate in landscape dynamics over time. We first conducted a remote sensing analysis to produce a land-cover map representing the biophysical dimension of the SES. This map is based on pixel-oriented classifications, using a 2017 Sentinel-2 satellite image and 610 GPS points, that categorized the landscape in 11 ecological classes. To study the landscape’s social dimension, we collected data on local knowledge to understand how local people perceive and use the landscape. These data were collected through 19 semi-structured individual interviews, three focus groups and three months of participant observation during an immersive field mission. We developed a systemic approach by combining data on biophysical and social dimensions of the landscape. Our analysis shows that in the absence of continued anthropic interventions, both savannahs and swamps dominated by herbaceous vegetation will experience closure by encroaching woody vegetation, leading to eventual biodiversity loss. Our methodology based on an SES approach to landscapes could improve the conservation programs developed by Ramsar site managers. Designing actions at the local scale, rather than applying one set of actions to the entire protected area, allows the integration of human perceptions, practices and expectations, a challenge that is more than essential in the context of global change.