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Une étude en vue d’évaluer le potentiel de séquestration du carbone des Agroforêts à base de Caféiers Robusta (ACR) a été menée dans quatre sites contrastés par leurs caractéristiques biophysiques et socioéconomiques, et appartenant à trois bassins de production du café au Cameroun. L’approche méthodologique a porté sur la collecte des données d’inventaires dans 120 ACR de différents âges (30 par site); lesquelles ont permis d’estimer le potentiel de séquestration du carbone de façon non-destructive en utilisant les équations allométriques. Le potentiel de séquestration du carbone évalués ont varié significativement entre les sites, de 67,84±45,41 t C.ha-1 à Ayos à 41,94±15,50 t C.ha-1 à Nkongsamba. Globalement, ces potentiels de séquestration du carbone diminuaient suivant le gradient d’anthropisation des sites d’étude. Les ACR des classes d’âge (années) de [30-45[et de [45-60[ont eu les potentiels de séquestration du carbone les plus élevés pour les Espèces associées (EA) et les caféiers respectivement. Le potentiel de séquestration du carbone des EA endogènes (19,46 t C.ha-1 ) était plus élevé que celui des EA introduites (6,32 t C.ha-1). Ces résultats montrent que la contribution des ACR dans les mécanismes d’atténuation des effets du changement climatique est une évidence qu’il faudrait capitaliser. English title: Carbon sequestration potential of robusta coffee agroforests (Coffea canephora var. robusta) in production basins of Cameroon A study to assess the carbon sequestration potential of Robusta coffee Agroforests (RCAs) was carried out in four sites, contrasted by their biophysical and socio-economic characteristics, and belonging to three coffee production basins in Cameroon. The methodological approach involves the collection of inventory from 120 RCAs of different ages, (30 per site), which allowed no-destructive estimation of carbon stocks using. The assessed carbon sequestration potentials evaluated varied significantly between sites, from 67.84 ± 45.41 Mg C.ha-1 in Ayos to 41.94 ± 15.50 Mg C.ha-1 in Nkongsamba. Overall, these carbon sequestration potentials decreased along the anthropization gradient of the study sites. RCAs of the [30-45[ and [45-60 [age classes (years) had the highest carbon sequestration potentials for associated species (Eas) and coffee trees respectively. The potential of carbon sequestration of the endogenous EA (19.46 Mg C.ha -1 ) was higher than that of the introduced EA (6.32 Mg C.ha -1). These results show that the contribution of RCAs in climate change mitigation mechanisms is evident and should be capitalized upon.

Malgré l’échec des initiatives de régénération à restaurer les écosystèmes de mangroves diversifiés et fonctionnels, les études sur le rôle joué par le milieu physicochimique sont rares. Cette étude a été menée pour déterminer les paramètres dendrométriques, les propriétés physicochimiques de l’eau et du sol et comment elles influencent le processus de régénération des mangroves. Pour cela, deux transects de 40 m de long et 10 m de large ont été établis par site, subdivisés ensuite en placettes de 100 m2 dans lesquelles les plantules ont été mesurées, des échantillons d’eau et de sol prélevés et analysés. Les tests statistiques ANOVA à un facteur et de corrélation de Pearson, au seuil de 5%, ont été utilisés pour, respectivement, comparer les deux sites et croiser les catégories de paramètres. Les meilleurs paramètres dendrométriques ont été enregistrés dans la parcelle de régénération naturelle de Tiko. Les valeurs des propriétés physicochimiques de l’eau montraient que ce site, proche du milieu urbain, est plus pollué que la plantation de Mbiako, situé en milieu rural. Par ailleurs, les sols étaient organiques et hyper acides mais soumis à une faible minéralisation. La matrice de corrélation montrait une forte influence des propriétés physicochimiques de l’eau en particulier la turbidité, salinité, conductivité et résistivité électriques et les solides totaux dissouts mais aussi de certaines propriétés chimiques du sol comme le potassium, sodium, phosphore et potentiel hydrogène sur le diamètre, hauteur et densité des plantules. De ces résultats, il faudrait prendre en compte ces facteurs déterminants lors des opérations sylvicoles pour garantir le succès des initiatives de régénération des mangroves. English title: Characterization of physicochemical and dendrometric parameters in mangrove regeneration treatments of the Cameroon Estuary Despite the failure of regeneration initiatives to restore diversified and functional mangrove ecosystems, the studies on the role of physicochemical environment are rare. This study was conducted to determine dendrometric parameters, physicochemical properties of water and soil and how the latter could influence the mangrove regeneration processes. So two transects of 40 m long and 10 m wide were established per study area. Those transects were then divided into plots of 100 m2 inside which seedlings were measured, soil and water samples were taken and analyzed. The one way ANOVA and correlation tests, at 5% threshold, were used, respectively, to compare the two study areas and correlate the parameter categories. The best dendrometric parameters were observed in the Tiko natural regeneration parcel. The values of physicochemical properties of water showed that this site, close to the urban zone, is more polluted than the one of Mbiako plantation, situated in rural zone. Moreover, the soils of the two sites were hyper acidic and organic but submitted to low mineralization processes. The Pearson correlation table showed a high influence of physicochemical parameters of water particularly the turbidity, salinity, electric conductivity and resistivity and the total dissolved solids in water but also some chemical properties of soil such as potassium, sodium, phosphorous and hydrogen potential on diameter, height and density of seedlings. According to these results, it is necessary to take into account those determinant factors during forestry operations for guarantee the success of mangrove regeneration initiatives.

Bamboo is of ecological and socio-economic importance in the world. However, knowledge on its potential in climate change mitigation remains superficial in Cameroon. The present study identified bamboo diversity and estimated carbon stocks of the dominant species in Cameroon. Ground truth method and local informants were used for a bamboo species survey in five Agro-ecological zones (AEZs). Twenty-two circular plots of 100 m² each were utilized for biomass and density data collection in AEZ 2, AEZ 3 and AEZ 4. Destructive method was used to collect 5% of culms per plot sampled for bamboo biomass estimation. Culm density and carbon stocks for each bamboo species were extrapolated to hectares. A total of 8 bamboo species were recorded in the inventory. Three dominant bamboo species were identified (Bambusa vulgaris, Oxytenanthera abyssinica and Phyllostachys aurea) in different AEZs. For the three dominant bamboo species, biomass of culm was greater (76-84%), than those of branches (13-19%) and leaves (4-9%). Culm density varied significantly across the different bamboo species, that is, 2296, 4374 and 38017 culm/ha respectively for B. vulgaris, O. abyssinica and P. aurea. Carbon stocks varied from 13.13 tC ha-1 (O. abyssinica); 29.62 tC ha-1 (B. vulgaris) and 67.78 tC ha-1 (P. aurea), with significant variations (P< 0.05) across the different bamboo species. The fast growth rate of bamboo underpins its potential for climate change mitigation and could influence decisions and strategy for the fight against climate change in Cameroon. Key words: Agro-ecological zone, climate change mitigation, culm density, REDD+ strategy, Cameroon.

The carbon storage capacity and allometry for bamboo in forest ecosystems has been neglected in the Congo Basin. This study evaluated the above ground carbon stocks and develop allometry for Bambus...

Ecotourism has been reported as a sustainable measure of bridging conservation goals and livelihood sustenance around protected areas, with very little information on the Campo Ma’an National Park (CMNP). This study was initiated to assess the impact of ecotourism activities on the livelihood of the local population living around the CMNP. Data were collected with questionnaires through household surveys and focus group discussions, interviews with key informants and observations in 9 communities. Chi-square test, Spearman’s rank correlation and regressions were used for data analysis. The study revealed that 65% of the local population perceived that ecotourism activities do not contribute to livelihood improvement. Chi-square statistics and Spearman rank correlation coefficients showed that the main factors plausibly affecting the impact of ecotourism activities around the CMNP on the local population’s livelihood were community, gender, main and secondary occupation, level of education, ethnic group, and number of children. Coefficients of the logistic regression model indicated that the main factors influencing the impact of ecotourism around the CMNP on the local population’s livelihood were gender (β = 1.218; p

Ecotourism is often perceived as a strategy for sustainable biodiversity conservation for protected areas. In Cameroon, there is dearth of information on the impacts of ecotourism on biodiversity conservation of protected areas. The main thrust of this study is to examine local population's perceptions of the impact of ecotourism on biodiversity conservation in and around the Campo Ma'an National Park (CMNP). Data were collected from both primary and secondary sources. Primary data were gotten from household survey (N=124), focus group discussions (N=8) and key informant interviews (N=16). From the findings, 44.4% of the local population perceived ecotourism activities contributing to biodiversity conservation of CMNP against 55.6% with contrary views. Spearman rank correlation coefficients and Chi-square test statistics indicated that, variables plausibly influencing local population's perception of ecotourism impact on biodiversity conservation in and around CMNP were age (p