Guide methodologique des etudes ecologique et genetique sur la disponibilite de quelques especes a usage-multiples dans et autour des concessions forestieres dans le bassin du Congo

x, 205 p.; 21 cm

Safeguarding villagers’ access to foods from timber trees: Insights for policy from an inhabited logging concession in Gabon

This study assessed the abundance of and access to tree species (Ozigo, Dacryodes buettneri; and Abam, Gambeya lacourtiana) that yield edible fruits to villagers and timber to the logging industry in and around a logging concession in Gabon. Participatory mapping combining GPS coordinates and interviews was carried out with 5 female and 5 male collectors in each of two villages within or adjacent to the logging concession. Precommercial and harvestable (>70 cm dbh) Ozigo and Abam trees, as well as their stumps, were also quantified on 20 five ha plots in the 2012 cutting area of the concession and on 21 five ha plots on 10 km transects from each village. Distances to 59 Abam and 75 Ozigo from which fruits were collected ranged from 0.7 to 4.46 Km from the village centres. Most collections were by mixed groups made up of men, women and children (54%) at an average of 1.21 ± 0.09 km; or by men and women (18%) at 2.21 ± 0.15 km; or women and children (14%) at 4.03 ± 0.22 km from the village. Almost 28% of all of the collection trees were inside the logging concession boundaries but outside the village agricultural zone, 43% were inside the village agricultural zone, and 29% were outside the logging concession. Only 33% of Ozigo collection trees had reached commercial size while 75% of Abam trees had. No stumps were found on any sample plots, probably reflecting the ban on felling Ozigo which was in effect at the time; and the relatively low commercial value of Abam. Densities of precommercial Ozigo trees in the cutting area were more than double their densities around the villages (236.0 ± 20.3100 ha−1and 96.6 ± 17.2100 ha−1, respectively), while densities of harvestable Ozigo trees were 7 times higher in the cutting area than around villages (120 ± 20.2100 ha−1and 17.1 ± 3.4100 ha−1respectively). This probably reflects past and current anthropogenic pressures around the villages, including logging and land clearance for agricultural fields. Densities of precommercial Abam were almost four times higher around the village (22.3 ± 5.6 and 6.0 ± 2.9) than on the cutting area. Villagers did not record a decline in availability of or access to these fruits over the past 5 years, suggesting little or no immediate conflict between timber production and access to fruits from these trees

Trees for Food and Timber: are community interests in conflict with those of timber concessions in the Congo Basin?

Much of the Congo Basin is managed for timber from dozens of species. More than 60% also produce non-timber products, including foods. For five multiple use tree species in Cameroon, Democratic Republic of Congo (DRC) and Gabon (Entandrophragma cylindricum, Baillonella toxisperma, Erythrophleum suaveloens, Dacryodes buettneri and Gambeya lacourtiana), we studied gathering and consumption by communities, edible caterpillars hosted, the densities of trees around villages and in concessions and the impacts of timber harvesting . We also studied the consumption of forest foods and the nutritional values of fruits and seeds of various tree species. Villagers walked up to six km during day trips to collect fruits or caterpillars, gathering from concessions if the village was within or near it. When foods were gathered from trees smaller than the cutting diameter (which varied by country and species), there was no conflict with timber harvesting. However, the volume of edible caterpillars hosted increased with diameter and harvestable trees were the most productive. Caterpillars, tree fruits and seeds provide fats, vitamins and minerals that complement agricultural foods. Densities of B. toxisperma, valued for its edible oil, were higher around villages than in concessions. The proportion of commercial trees harvested for timber varied from less than 3% to more than 50%, depending on the species. Different species had different geneflow distances, meaning viable regeneration could be expected with residual adults at different maximum distances. E. cylindricum had more effective dispersal than E. suaveolens. The production of timber and nontimber products can be sustained from the same concessions, for different stakeholders, with appropriate practices and arrangements

Beyond timber: balancing demands for tree resources between concessionaires and villagers

Extensive areas of the Congo Basin forest are allocated to timber concessionaires. These forests also harbour and support village populations, including indigenous Baka people, who depend on forest foods obtained directly from trees (fruits, oils and caterpillars). Most food-producing tree species are harvested by concessionaires for timber. We documented the availability and abundance of three food tree species around four villages and in two neighboring timber concessions in Cameroon. Data was used to determine the importance of timber concessions as sources of food for local people to provide a foundation for governance arrangements that consider local needs for foods from timber trees. Discussions with concessionaires revealed that some of them have voluntarily refrained from extracting timber species of interest to villagers for their nontimber products. This is either to avoid conflict with villagers, or because regulations have been promulgated to safeguard these resources. The interplay between internal village dynamics, regulations and their implementation by forest guards, and the actions of timber concessions create a complex arena for addressing rights to forest resources. This paper provides information on the accessibility and availability of multiple use timber species as a foundation for negotiations and governance arrangements between concessionaires and local communities

Do logging concessions decrease the availability to villagers of foods from timber trees? A quantitative analysis for Moabi (Baillonella toxisperma), Sapelli ( Entandrophragma cylindricum ) and Tali (Erythrophleum suaveolens) in Cameroon

Many species of timber trees in Cameroon are exploited by logging companies for timber and by forest- dependent communities for non-timber forest products (NTFPs). Quantitative analyses were conducted within and near forest concessions in Cameroon to determine the density of multiple use tree species that provide both timber for industry and foods consumed by local populations (fruit and oil or edible caterpillars), and how this has been affected by logging. Individuals of the three species (Moabi, Baillonella toxisperma; Sapelli, Entandrophragma cylindricum; and Tali, Erythrophleum suaveolens ), including their stumps, were identified and measured on 5 ha (100 m 500 m) sample plots around 4 villages and in 2 concessions. Around each village 21 sample plots, stratified by distance, were laid out along three transects extending 10 km towards the concession, each oriented 45 from the other. In concessions, 20 plots were established within the 2012 cutting unit after timber harvesting, using a stratified random system. Moabi trees occurred at the lowest densities: around villages, 22.8 ± 3.3/100 ha of precommercial individuals and 5.0 ± 1.4/100 ha of individuals of harvestable size (P80 cm dbh); on concessions, 7.5 ± 2.4 precommercial trees/100 ha, and 0–2.0 ± 1.4/100 ha harvestable individuals. Densities of Sapelli trees were not significantly different between villages and concessions, averaging 32.6 ± 3.8/100 ha and 37.5 ± 5.5/100 ha, respectively, for precommercial sizes and 9.5 ± 2.2/100 ha and 6 ± 1.6/100 ha, respectively, for harvestable trees ( P 100 cm dbh). Pre-commercial Tali trees occurred at lower densities (3.8 ± 0.9/100 ha) around villages, as compared to 11.5 ± 3.1/100 ha on concessions. Harvestable Tali trees (P 60 cm dbh) occurred at the same densities around villages and on concessions (56.0 ± 7.2/100 ha). Half, or more, of commercial-sized trees of caterpillar-hosting species were left standing after harvest on concessions (89–94% of Tali; 50–79% of Sapelli), reflecting constraints due to timber quality, market demand and inaccessibility. No harvestable Moabi trees were logged from the 2012 cutting areas, reflecting agreements between communities and concessionaires to leave them for fruit and oil, but densities were so low it will be important that villagers conserve those around their villages. Stumps of all three species were found around villages, revealing that mechanisms for negotiation are also needed among villagers with interests in either timber or non-timber resources obtained from the same tree species

Individuals and stumps of Moabi, Sapelli, Tali, Ozigo and Abam (timber species with food values) recorded around villages and within logged areas of timber concessions in Cameroon, Gabon and the DRC.

This dataset contains individuals of Baillonella toxisperma, Entandrophragma cylindricum, Erythrophleum suaveolens, Dacryodes Buettnerii and Gambeya spp('spp'), around 10 villages ('vil'), and within five logging concessions ('conc') in Cameroon, Gabon and the DRC ('pays'). There are columns indicating the diameter at breast height ('dbh' – cm). To determine the density and abundance of the selected species within the concession and around the villages, trees were identified and sampled on plots. Within the concessions, sample plots were established in the 2012 cutting area. Five plots of 5 ha each were established at random within each of the four quadrants (North, South, East and West) of the 5 000 ha cutting area, for a total of 20 sample plots. To evaluate the density of trees around villages, 21 sample plots of 5 ha each were laid out around each village along three transects extending from the village centre towards the forest concession to a maximum distance of 10 km. The total sample area described a half circle of 157 km2 (15,700 ha). The central transect (“B”) was oriented towards the forest concession and the transects “A” and “C” were laid out at 450 C to each side of it (Figure 2). Sample plots around villages were also stratified among four different distance bands, 1-1.9 km (stratum A), 2-3.9 km (stratum B), 4-6.9 km (stratum C) and 7-10 km (stratum D) from the village centre. To obtain a sampling intensity of 0.5% in each stratum, the number of plots per stratum increased in each band of increasing distance. In both the concession and around villages, sample plots were 100 m x 500 m in size. Around villages, plot boundaries extended 100 m along the transect line and 500 m to one side or the other, alternating. Within each plot, all individuals of target species (dbh ≥ 20 cm) were identified and their diameters at breast height (dbh) measured using diameter tapes. When trees had buttresses, diameters were measured at 50 cm above the buttresses with GPS coordinates recorded at each corner of the sampled plots. Stumps were also sought, identified and measured

Chronic human disturbance and environmental forces drive the regeneration mechanisms of a Caatinga dry tropical forest

It is now clear that dry forest regeneration relies on a set of regeneration mechanisms such as seed rain, seed and seedling banks, and resprouts that operate simultaneously, but their relative contribution and drivers remain poorly understood. In this paper, we examined the role of seed rain, seed soil bank, seedling, sapling, and resprout assemblages in the regeneration of a Caatinga dry forest in northeast Brazil. We also examined how these regeneration mechanisms respond to chronic disturbances, rainfall, soil fertility, and light in 18 plots located in old-growth forest stands. A total of 5239 seeds from seed rain, 932 seeds in the soil seed bank, 158 seedlings, 85 saplings and 416 resprouts were recorded. Overall regeneration mechanisms provided low-density and impoverished assemblages when examined isolated. Soil seed bank and seed rain provided up to 423 and 35.5 seeds per m2, respectively. Seedling and sapling assemblages were dominated by a small set of species (mostly Jatropha mutabilis, Pityrocapa moliliformis, and Trischidium molle), which were both frequent and accounted for most of the individuals. Resprouting was the most important mechanism, accounting for 63.1% of all individuals in the seedling, sapling, and resprout assemblages. Chronic disturbances were identified as key drivers, negatively affecting several community-level attributes of seed rain, soil seed bank, seedlings, and resprouts. Soil fertility and leaf area index (i.e., light availability) were negatively related to seedling and sapling abundances, respectively. Furthermore, the effect of environmental factors on regeneration was more pronounced in disturbed areas. Species composition of saplings and resprouts were associated with chronic disturbances and environmental factors. Our results suggest that, in human-modified landscapes, Caatinga forest regeneration relies primarily on resprouting, while other mechanisms play a minor role in plant species recruitment and maintenance along gradients of disturbances and environmental factors. Given the predicted increase in aridity associated with increased human disturbance, the Caatinga dry forest may experience shifts in forest structure and regeneration patterns. We refer to an absolute prevalence of vegetative propagation leading to a low-statured forest dominated by multi-stem individuals, with unknown effects on long-term forest dynamics and resilience, including community-level homogenization