Pterocarpus erinaceus is a native tree species of the Guineo-Sudanian and Sudano-Sahelian zones where natural stands are under constant pressure and heavily exploited for timber, animal feeding and others uses. A part from the overexploitation, climate change could also become a serious threat to the species natural distribution. For that purposes, this study aims to assess the vulnerability of P. erinaceus potential niche to climate change within its natural distribution area in West Africa. Niche predictions are based on 6,981 natural occurrence of the species and 19 global bioclimatic variables available through WorldClim. The future niche of the species is predicted according to three concentration pathways (RCPs 2.6, 4.5 and 8.5) of BC model for 2050 and 2070, thanks to Maxent software. P. erinaceus is currently reported from Senegal to Cameroon. Its potential niche covers the Sudano-Sahelian zone and the Dahomey gap on approximately 17.42% of the total area of these countries. In general, the niche of the species is not sensitive to climate change, regardless of the climate scenario and the year. Compared to its initial niche, the niche of the species will increase from 22.33% to 43.61% in 2050 and from 27.12% to 53.61% in 2070. However, this ecological expansion observed mainly in the Gulf of Guinea, will be associated with a considerable decrease in the Sahel and central Nigeria. This study shows the importance of promoting the development of innovative silvicultural strategies for the extension and restoration of natural stands of P. erinaceus in order to meet sustainably the timber needs of the West African region. It helps also to strengthening the roles of natural forests in providing ecosystem services and mitigating climate change effects.
Structure des peuplements naturels de Pterocarpus erinaceus Poir.dans le domaine soudanien, au Niger et au Burkina Faso erinaceus augmente de manière significative (P < 0,003) de la zone sahélo-soudanienne à la zone soudano-guinéenne : 1,2 ± 0,7 pied/ha dans la zone sahélo-soudanienne ; 2,6 ± 2,2 pieds/ha dans la zone nord-soudanienne ; 6,1 ± 4,6 pieds/ha dans la zone sud-soudanienne ; 15,0 ± 1,1 pieds/ha dans la zone soudano-guinéenne. L'analyse des structures en diamètre et en hauteur révèle une augmentation de la fréquence des individus jeunes suivant le gradient pluviomé-trique. Par contre, l'intensité de l'exploitation est plus élevée dans les zones les moins arrosées, où l'espèce s'avère menacée.B o i s e t f o r ê t s d e s t r o p i q u e s , 2 0 1 5 , n° 3 2 5 ( 3 ) PTEROCARPUS ERINACEUS 71 B o i s e t f o r ê t s d e s t r o p i q u e s , 2 0 1 5 , n° 3 2 5 ( 3 )
The Mono Transboundary Biosphere Reserve (RBTM) has significant resources but faces many threats that lead to habitat fragmentation and reduction of ecosystem services. This study, based on satellite image analysis and processing, was carried out to establish the baseline of land cover and land use status and to analyze their dynamics over the period 1986 to 2015. The baseline of land cover established six categories of land use including wetlands (45.11%), mosaic crops/fallow (25.99%), savannas (17.04%), plantation (5.50%), agglomeration/bare soil (4.38%) and dense forest (1.98%). The analysis of land use dynamics showed a regression for wetlands (-23%), savannas (-16.06%) and dense forest (-7.60%). On the contrary, occupations such as mosaic crops/fallow land, urban agglomerations/bare soil and plantation increase in area estimated at respectively 128.64%, 93.94% and 45.23%. These results are of interest to stakeholders who assess decisions affecting the use of natural resources and provide environmental information essential for applications ranging from land-use planning, forest cover monitoring and the production of environmental statistics.Keywords: Land use, baseline, spatial dynamics, environmental statistics, ecological monitoring.
Pterocarpus erinaceus (Poir) is currently the most exploited and threatened spontaneous tree species in the Guinean-Sudanian and Sudano-Sahelian zones in West Africa. This work analyzed the density and color parameters of P. erinaceus wood in the phytogeographic zones (Sudanian, Guinean and Sahelian) in three countries in West Africa (Togo, Burkina Faso and Niger). The results obtained by studying 451 specimens taken from 95 trees showed significant differences in basic density and color parameter values (P < 0.001) based on phytogeographic zones. Individual tree samples from the Sahelian zone were denser (780 ± 63 kg · m − 3), darker (L* = 48.3 ± 0.6) and redder (a* = 8.2 ± 2) than those in the Guinean zone (basic density = 684 ± 53 kg · m−3; L* = 59.7 ± 0.5; a* = 6 ± 0.2) and the Sudanian zone (basic density = 725 ± 70 kg · m−3; L* = 53.7 ± 0.40; a* = 7.30 ± 0.2). At intra-tree scale, the results did not show a significant variation of basic density according to the number of rings counted from the pith (P > 0.05). This indicated that the age of the trees has little influence on the basic density of P. erinaceus wood.
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.