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a Guinea-Bissau in the African Continent, b Cacheu region, the Cacheu protected area and the study area, c Landsat OLI (RGB754) color composite of the year 2019, with the study area defined by the sea branch surrounding Djobel village
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Fig1
Djobel is a northern Guinea-Bissau island-village located close to Casamance-Senegal border (Fig. 1), inside the Cacheu Mangroves National Park (PNTC). Djobel village and rice fields are a bunch of small islands linked by intertidal mangroves (Figs. 1 and 3).
Partial view of a council of elders' meeting following a ritual at one of the main spirit's shrines
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Fig2
They have a segmentary (non-hierarchical) political organization, governed by a body of elders (Fig. 2) with both political and religious powers (Linares,).
Djobel, Arame, and Elia islands located over a topographic map (1:50 000) from 1953 and produced by Ministerio do Ultramar:Junta das Missoes Geograficas e de Investigacoes do Ultramar
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Fig3
Djobel village and rice fields are a bunch of small islands linked by intertidal mangroves (Figs. 1 and 3).
Google Earth high-resolution image of one of Djobel's neighborhoods (9/11/2018)
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Fig4
Almost seven decades of observation (Figs. 4 and 5) reveal a substantial loss of swamp rice fields (an annual net loss of -2.4%) and a regeneration of mangrove areas (an annual net gain of 0.8%), together with an increase in flooded land and mud (an annual net gain of 2.9%).
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Google Earth high-resolution image of one of Djobel's neighborhoods (9/11/2018)
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Fig4
Almost seven decades of observation (Figs. 4 and 5) reveal a substantial loss of swamp rice fields (an annual net loss of -2.4%) and a regeneration of mangrove areas (an annual net gain of 0.8%), together with an increase in flooded land and mud (an annual net gain of 2.9%).
Land cover maps for the core study area in the period 1953-2019. The first two years (1953 and 1976) were obtained from topographic map (1:50 000) produced by Ministerio do Ultramar:Junta das Missoes Geograficas e de Investigacoes do Ultramar and from aerial photography (1:100 000) produced by the Institut National de l'Information Geographique et Forestiere (IGN), and 1990-2019 was obtained from Landsat satellite images
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Fig5
Almost seven decades of observation (Figs. 4 and 5) reveal a substantial loss of swamp rice fields (an annual net loss of -2.4%) and a regeneration of mangrove areas (an annual net gain of 0.8%), together with an increase in flooded land and mud (an annual net gain of 2.9%). Additionally, some of the rice fields were covered by mangroves (as confirmed in Figs. 5 and 6 for the year 1976). At that time, no water was visible inside the main polder, where both the houses and the nearer rice fields were located (as confirmed in Fig. 5). This can be observed in the land cover map of 2007, where large areas of Djobel's previous rice fields are shown flooded and covered in mud (Fig. 5). Despite these events, in 2007 and 2015 there was a small decrease in the mangrove area due to attempts to open some new rice fields, but in 2019, the cultivation area contracted again (see also Figs. 5 and 6). Meanwhile, flooded areas have been progressively covered by mangroves (Figs. 5, 6 and 7).
Land cover evolution and net annual change rates in the period 1953-2019 for each land cover type. The first two years (1953 and 1976) were obtained from topographic map (1:50 000) produced by Ministerio do Ultramar:Junta das Missoes Geograficas e de Investigacoes do Ultramar and from aerial photography (1:100 000) produced by the Institut National de l'Information Geographique et Forestiere (IGN); for 1990-2019, data was obtained from satellite images
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Fig6
Additionally, some of the rice fields were covered by mangroves (as confirmed in Figs. 5 and 6 for the year 1976). Despite these events, in 2007 and 2015 there was a small decrease in the mangrove area due to attempts to open some new rice fields, but in 2019, the cultivation area contracted again (see also Figs. 5 and 6). Meanwhile, flooded areas have been progressively covered by mangroves (Figs. 5, 6 and 7).
View of a new contour dike and of a former rice field now covered with mangroves planted by Djobel inhabitants
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Fig7
Meanwhile, flooded areas have been progressively covered by mangroves (Figs. 5, 6 and 7).
Houses settled on minute "islands"
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Fig8
Many families now have their houses on what could be called minute islands (e.g., Figs. 8 and 9).
View of a settlement at low tide
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Fig9
Many families now have their houses on what could be called minute islands (e.g., Figs. 8 and 9).
a and b: Partial view of the destruction produced by Arame villagers in Djobel's new settlement (photos taken by Djobel villagers in July 2021 and sent to the first author through WhatsApp).
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Fig10
However, the house foundations, hundreds of cement bricks (the area becomes flooded during the rainy season and the traditional mud bricks cannot be used), and the drinking water infrastructure built with the financial support of the state and the UN were all destroyed one night by Arame villagers (see Fig. 10), some of whom were caught by soldiers and imprisoned.