African Forest Research Articles

Vegetative propagation of Xylopia parviflora, a wild medicinal spice tree species in the tropics: insights for domestication

Objective: Xylopia parviflora (A. Rich.) Benth. (commonly known as “striped African pepper”) is one of the most socio-economically high-valued tree species of the Central and Western African humid forests. Its propagation is hindered by poor seed germination. The present study aimed at examining its potential for vegetative propagation through the rooting of stem cuttings. Methodology and Results: In a split-plot experimental design, three leaf areas (0, 15 and 30 cm2) and six concentrations [(0, 0.25, 0.5, 1, 2 and 4% (w/w)] of indole-3-butyric acid (IBA) were tested for their effects on stem cutting parameters after five months in a non-mist propagator. Maximum rooting percentage (100%) was recorded with 15 cm2 x 4% IBA, 30 cm2 x 2% IBA and 30 cm2 x 4% IBA treatment combinations. The highest mean root count (9.1) was recorded with 30 cm2 x 4% IBA. The mortality rate of cutting was significantly affected by leaf area only. Leafless cuttings (0 cm2) resulted in 73.5% mortality, which was higher than 11.8% and 10.7% recorded with cuttings having 15 and 30 cm2 leaf areas respectively. Conclusion and application of findings: X. parviflora is amenable to vegetative propagation through rooting of leafy stem cutting within five months. For an efficient propagation of X. parviflora through stem cuttings, the use of cuttings with 30 cm2 leaf area and application of 4% (w/w) IBA are recommended. This is valuable insight into the domestication and in situ conservation of this species that is of direct relevance to the well-being of millions of people in sub-Saharan Africa. Propagation of X. parviflora using robust and low-cost procedure as described in this study would stand as an alternative to the sexual propagation which is hindered by poor seed germination. Keywords: auxin, leaf area, rooting, stem cuttings, striped African pepper.

Diversity, abundance, and conservation status of woody species in a West African dry forest

AbstractThis study presents data on woody plant species richness and diversity of an inaccessible dry forest of Tula Mountains Woodland (TMW) located in the northeast of Nigeria. TMW supports a minimally disturbed mosaic of dry forest‐woodland. We sampled woody species in 190 plots of size 0.01‐ha, spaced 50 m apart on series of line transects. We found a total of 133 woody species belonging to 88 genera and 39 families in 1.9 ha area sampled in total. Out of 133 species, 120 were identified to species level, and 113 were recorded as trees, shrubs and lianas with diameter at breast height (dbh) ≥ 5 cm. Species accumulation curve was non‐asymptotic. Fisher's logseries model suggests that the plots sampled in the dry forest communities of TMW are represented by a high number of rare species. Of 120 identified species, 46 (38%) lacked evaluation on conservation status by IUCN. Out of 74 (62%) evaluated species, 2 were listed as critically endangered, 3 were vulnerable, and 69 were of least concern. In the TMW, 27% of woody species were restricted to Sudanian savannah biome, 61% occurred in Sudanian and Zambezian savannah biome. TMW serves as refugia for native plant species and plant communities in northeastern Nigeria.

Integrating RADAR and optical imagery improve the modelling of carbon stocks in a mopane‐dominated African savannah dry forest

AbstractThis study examined the integration of two satellite data sets, that is Landsat 7 ETM+ and ALOS PALSAR (Advanced Land Observing Satellite Phased Array type L‐band Synthetic Aperture RADAR) in estimating carbon stocks in mopane woodlands of north‐western Zimbabwe. Mopane woodlands cover large spatial extents and provide ecosystem benefits to the rural economies and grazing resources for both livestock and wildlife. In this study, artificial neural networks (ANN) were used to estimate carbon stocks based on spectral metrics derived from Landsat 7 ETM+ and ALOS PALSAR. To determine the utility of the two satellite‐derived metrics, a two‐pronged modelling framework was adopted. Firstly, we used spectral bands and vegetation indices from the two satellite data sets independently, and subsequently, we integrated the metrics from the two satellite data sets into the final model. Results showed that the ALOS PALSAR (R2 = 0.75 and nRMSE = 0.16) and Landsat ETM+ (R2 = 0.78 and nRMSE = 0.14) derived spectral bands and vegetation indices comparatively yielded accurate estimations of carbon stocks. Integrating spectral bands and vegetation indices from both sensors significantly improved the estimation of carbon stocks (R2 = 0.84 and nRMSE = 0.12). These findings underscore the importance of integrating satellite data in vegetation biophysical assessment and monitoring in poorly documented ecosystems such as the mopane woodlands.

Social factors drive vocal exchanges in red-capped mangabeys (Cercocebus torquatus)

Of all the calls made by non-human primates, the function of short-distance contact calls has largely remained to be determined. These calls are the most frequent in the repertoire and are most often exchanged between individuals in a non-random way. To our knowledge, no study has ever examined how vocal exchanges are structured in red-capped mangabeys (Cercocebus torquatus), a semi-terrestrial monkey living in the African forest with a complex semi-tolerant/semi-despotic social system. Our goal was to assess the organization of contact call exchanges in this species and their relationship with individual and social factors such as age, affinity, and hierarchy. Therefore, we observed several captive groups of red-capped mangabeys and collected data on vocal behavior, as well as grooming, agonistic behavior, and spatial proximity. We defined a vocal exchange in this species as a series of contact calls made by two or more individuals within a maximum inter-caller interval of 2 s. At the individual level, the higher the individual's hierarchical rank, the less they initiated exchanges. Furthermore, the most socially integrated individuals had a longer average response time than the less integrated ones. At the dyadic level, preferred exchange partners were individuals often observed near one other or individuals most distant in age. Also, the further apart two individuals were in the dominance hierarchy, the shorter the response time. Our results support both the social bonding hypothesis and a modulating key role of the dominance hierarchy on the social use of contact calls, which is in line with the social style of this species.

DNA integrity and viability of testicular cells from diverse wild species after slow freezing or vitrification.

Cryopreservation of testicular tissues offers new possibilities to protect endangered species, genetically valuable individuals or even the fertility potential of prepubertal individuals who have died unexpectedly. However, the use of this technique still remains a challenge. In this study, slow freezing and vitrification of testicular tissue was investigated to find out which cryopreservation method could better preserve the viability and DNA integrity of testicular germ cells in diverse wild species. Testes were obtained post-mortem from 18 artiodactyls (wild boar, roe deer, dwarf goat, mhor gazelle, European mouflon, African forest buffalo, Malayan tapir, dorcas gazelle, Iberian ibex, gnu, red river hog), 5 primates (colobus monkey, capuchin monkey, mandrill), 8 carnivores (gray wolf, Persian leopard, binturong, European mink, American black bear, suricata), and 2 rodents (Patagonian mara). The testicles belonged to adult individuals and were cut into small pieces and cryopreserved by needle immersed vitrification or uncontrolled slow freezing using a passive cooling device. After warming or thawing, testicular tissues were enzymatically digested and two germ cell types were differentiated based on their morphology: rounded cells (spermatogonia, spermatocytes, and early spermatids) and elongated cells (elongated spermatids and spermatozoa). Cell viability was assessed by SYBR-14/propidium iodide while DNA fragmentation by TUNEL assay with fluorescence microscope. Our preliminary results revealed that our uncontrolled slow freezing method better preserved the viability and DNA integrity of elongated cells than vitrification. Such trend was observed in all species, being significant in artiodactyls, carnivores, and primates. Similarly, the viability and DNA integrity of rounded cells was also better maintained in primates by uncontrolled slow freezing, while in carnivores, vitrification by needle immersion showed better results in this type of cells. In artiodactyls and rodents both techniques preserved the viability of rounded cells in a similar manner, although the DNA integrity of these cells was greater after needle immersed vitrification in artiodactyls. In conclusion, the effectiveness of each cryopreservation method is affected by the phylogenetic diversity between species and cell type.

First evidence of a monodominant (Englerodendron, Amherstieae, Detarioideae, Leguminosae) tropical moist forest from the early Miocene (21.73 Ma) of Ethiopia.

Many tropical wet forests are species-rich and have relatively even species frequency distributions. But, dominance by a single canopy species can also occur in tropical wet climates and can remain stable for centuries. These are uncommon globally, with the African wet tropics supporting more such communities than the Neotropics or Southeast Asia. Differences in regional evolutionary histories are implied by biogeography: most of Africa's monodominance-forming species are Amherstieae-tribe legumes; monodominance in Neotropical forests occur among diverse taxonomic groups, often legumes, but rarely Amherstieae, and monodominance in Southeast Asian forests occurs mostly among Dipterocarpaceae species. African monodominant forests have been characterized ecologically and taxonomically, but their deep-time history is unknown despite their significant presence and bottom-up ecological influence on diversity. Herein we describe fossil leaflets of Englerodendron mulugetanum sp. nov., an extinct species of the extant genus Englerodendron (Berlinia Clade, Amherstieae, Detarioideae) from the 21.73 Ma Mush Valley site in Ethiopia. We also document a detailed study of associated legume pollen, which originate from a single taxon sharing characters with more than one extant descendant. Taxonomically, the pollen is most comparable to that from some extant Englerodendron species and supports a likely affiliation with the Englerodendron macrofossils. The Mush Valley site provides the first fossil evidence of a monodominant tropical forest in Africa as represented by leaflets and pollen. Previous studies documented >2400 leaves and leaflets from localities at six stratigraphic levels spanning 50,000-60,000 years of nearly continuous deposition within seven meters of section; all but the basal level contain ≥ 50% E. mulugetanum leaflets. Modern leaf litter studies in African mixed vs. monodominant forests indicates the likelihood of monodominance in the forests that surrounded the Mush paleolake, particularly after the basal level. Thus, we provide an early case for monodominance within the Amherstieae legumes in Africa.

A focus on the last 1000 years of natural environmental changes in the tropical rainforests of West and Central Africa. Can we detect anthropogenic disturbances?

The vast tropical rainforests of West and Central Africa were impacted by marked climatic deterioration, which mainly developed between 2500 and 2000 cal yr BP. However, the incidence of human intervention in these rainforests appears all the more speculative, although this was the period when the first stages of Bantu migration occurred towards the south. On the scale of the last millennium, which has seen increasing penetration and colonization of these Bantu peoples, one can envisage a priori a more accentuated anthropogenic pressure on the forest landscape. The combined observations of the environmental processes during the last 1000 years, as preserved in sediments from lakes, swamps, flooded forests and even oceanic environments, are presented on the basis of 24 records. The dominant number of sites in the humid forest or wooded savannas recorded only processes of relatively small size and local effects influencing vegetation cover almost simultaneously around 1000 and 500 cal yr BP; nothing is comparable with the devastating effect on a very large scale of the 2600 cal yr BP forest crisis. Conversely, other sites located in more perennial forest or savanna did not reveal any discontinuity. In all the examples of sedimentary archives considered, no out-of-phase or unusual event, possibly linked to human population and its impact, was observed. However, in more recent times, in intensive iron-ore mining/smelting areas, changes in the vegetal cover could be a legacy of charcoal production impacting forest biomass. Nevertheless, despite the clear cultural and socio-political importance of iron, its role in shaping vegetation communities in the Central African forest is generally presumed to be negligible. The oceanic causes of these climatic oscillations are more widely accepted. On a larger scale, the Medieval Warm Period and Little Ice Age are climatic anomalies visible in a number of palaeoenvironmental records worldwide and date to ∼1600–1000 cal yr BP and ∼ 700–100 cal yr BP, respectively. These events are less visible or sometimes not present in some palynological records of tropical Africa, whereas reconstructions from lacustrine records in Atlantic equatorial Africa show overall reductions in lake levels and increases in pollen belonging to light-demanding and pioneer vegetation formations in relation to these two oscillations. To reply to what was more important «the potential influence of human activities on regional climate, or the vulnerability of societies to environmental variability», it appears clearly to date, that the second paradigm is most likely. However, today, the ongoing combined efffects of climate change and human impact, including the decimation of the diversity of seed dispersers necessary to regenerate the rainforests of West and Central Africa, may have irreparable and unforeseen consequences.

Application of machine learning approaches for land cover monitoring in northern Cameroon

Machine learning (ML) models are a leading analytical technique used to monitor, map and quantify land use and land cover (LULC) and its change over time. Models such as k-nearest neighbour (kNN), support vector machines (SVM), artificial neural networks (ANN), and random forests (RF) have been used effectively to classify LULC types at a range of geographical scales. However, ML models have not been widely applied in African tropical regions due to methodological challenges that arise from relying on the coarse-resolution satellite images available for these areas. In this study, we compared the performance of four ML algorithms (kNN, SVM, ANN and RF) applied to LULC monitoring within the Mayo Rey department, North Province, Cameroon. We used satellite data from the Landsat 7 Enhanced Thematic Mapper Plus (ETM+) combined with 8 Operational Land Imager (OLI) images of northern Cameroon for November 2000 and November 2020. Our results showed that all four classification algorithms produced relatively high accuracy (overall classification accuracy >80%), with the RF model (> 90% classification accuracy) outperforming the kNN, SVM, and ANN models. We found that approximately 7% of all forested areas (dense forest and woody savanna) were converted to other land cover types between 2000 and 2020; this forest loss is particularly associated with an expansion of both croplands and built-up areas. Our study represents a novel application and comparison of statistical and ML approaches to LULC monitoring using coarse-resolution satellite images in an African tropical forest and savanna setting. The resulting land cover maps serve as an important baseline that will be useful to the Cameroon government for policy development, conservation planning, urban planning, and deforestation and agricultural monitoring.

Carbon of Chaillu forests based on a phytosociological analysis in Republic of Congo, more than meets the eye?

AbstractThe objectives were to quantify aboveground, belowground and dead wood carbon pools near Mayoko in the Chaillu massif of Republic of Congo and explore relationships between carbon storage and plant diversity of all growth forms. A total of 190 plots (25 m by 25 m) were sampled (5072 stems, 211 species) and data analysed using recommended central‐African forest allometric equations. Mean stem diameter at breast height was 33.6 cm, mean basal area 47.7 m2 ha−1 and mean density of individuals 407 ha−1. Mean aboveground carbon (AGC) ranged from 13.93–412.66 Mg C ha−1, belowground carbon from 2.86–96.97 Mg C ha−1 and dead wood from 0.00–7.59 Mg C ha−1. The maximum AGC value recorded in a plot was 916 Mg C ha−1. The analysis performed using phytosociological association as basis rather than broad vegetation type is unique. AGC values for undisturbed terra firme forest sites featured among the highest recorded for African tropical forests. Considering only tree diversity, a weak, yet significant, relationship existed between AGC and species richness, Shannon‐Wiener index of diversity and Fisher's alpha. However, if diversity of all plant growth forms is considered, no relationship between carbon and plant diversity existed.

Habitat conversion intensifies human elephant conflicts in the Eastern Wildlife Corridor, Ghana

Ghana was ranged by fairly large herds of elephants up until the 1970s (Douglas-Hamilton 1979). At one time elephants were found throughout the country but, as elsewhere on the continent, elephant habitat contracted during the 20th century. Today both the African savannah elephant (Loxodonta africana) and the African forest elephant (L. cyclotis) are still found, respectively, in the savannah and forest zones of Ghana. However, the populations are now confined to a few Protected Areas (PAs) and isolated remnant habitats, mainly due to human population pressure and related land use and land cover changes (AfESG 2000). Elephants are also killed illegally by poachers for the ivory trade, which dates back to ancient times (Parker 1973). By 2000, there were only eleven elephant population ranges in the country, with an estimated population of 1,000–2,000 individuals (WD 2000). These trends call for drastic and far-reaching elephant conservation efforts, including effective anti-poaching measures with more supportive legislation, and community-based land-use planning to foster harmonious human–elephant coexistence (HECx) in the country. Ghana has exhibited zeal for the conservation of the African elephant, both domestically and on the international front. Ghana was the first country to propose listing of African elephants in Appendix 1 of CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora). The country is also signatory to other international conventions, including the Convention on Biological Diversity (CBD), Ramsar Convention on Wetlands of International Importance, Convention on the Conservation of Migratory Species of Wild Animals (Bonn Convention) and the United Nations Framework Convention on Climate Change (UNFCCC), among others. In July 2008, Ghana entered into a bilateral cooperation agreement in the form of a memorandum of understanding (MOU) with the Republic of Burkina Faso for the purpose of conserving natural resources shared by the two countries, including savannah elephants. In 2000, the Wildlife Division of the Forestry Commission of Ghana, in collaboration with the World Wide Fund for Nature (WWF) and IUCN’s African Elephant Specialist Group (AfESG), developed an Elephant Conservation Strategy as a guide to ensure the conservation and survival of viable elephant populations and their habitats throughout the country. This strategy informed studies conducted of elephant migratory corridors by the Northern Savannah Biodiversity Conservation Project (NSBCP), under the auspices of the Global Environment Facility (GEF) and the World Bank, between 2002 and 2009. These studies identified two main elephant migratory routes between Burkina Faso and northern Ghana, which were designated the Eastern and Western Wildlife Corridors (EWWC). The forests and wildlife in the corridors are jointly managed by the Forest Services Division (FSD) and Wildlife Division (WD) of the Forestry Commission. This article provides a summary description of the EWWC, presents data on human–elephant conflict in the Eastern Wildlife Corridor, and discusses approaches to mitigate conflicts and ensure the survival of the elephant population in the corridor.

A Remote Sensing-Based Inventory of West Africa Tropical Forest Patches: A Basis for Enhancing Their Conservation and Sustainable Use

The rate of tropical deforestation is increasing globally, and the fragmentation of remaining forests is particularly high in arable landscapes of West Africa. As such, there is an urgent need to map and monitor these remnant forest patches/fragments and so identify their multiple benefits and values. Indeed, recognizing their existence will help ensure their continued provision of ecosystem services while facilitating their conservation and sustainable use. The aim of this study is therefore to inventory and characterise the current extent and change of remnant forest patches of West Africa, using multi-source remote sensing products, time-series analyses, and ancillary datasets. Specifically, we collate and analyse descriptive and change metrics to provide estimates of fragment size, age, biophysical conditions, and relation to social-ecological change drivers, which together provide novel insights into forest fragment change dynamics for over four decades. We map forests patches outside protected areas with a tree cover ≥30%, a tree height of ≥5 m, an area ≥1 km2 and ≤10 km2. Appended to each patch are descriptive and change dynamics attributes. We find that most fragments are small, secondary forest patches and these cumulatively underwent the most forest loss. However, on average, larger patches experience more loss than smaller ones, suggesting that small patches persist in the landscape. Primary forest patches are scarce and underwent fewer losses, as they may be less accessible. In 1975 most patches were mapped as secondary, degraded forests, savanna, woodland, and mangrove, and relatively few comprised cropland, settlements, and agriculture, suggesting that new forest patches rarely emerged from arable land over the past 45 years (1975–2020), but rather are remnants of previously forested landscapes. Greening is widespread in larger secondary fragments possibly due to regrowth from land abandonment and migration to urban areas. Forest loss and gain are greater across fragments lying in more modified landscapes of secondary forests, while forest loss increases with distance to roads. Finally, larger forest patches harbour a denser tree cover and higher trees as they may be less impacted by human pressures. The number and extent of West African forest patches are expected to further decline, with a concurrent heightening of forest fragmentation and accompanying edge effects. Lacking any conservation status, and subject to increasing extractive demands, their protection and sustainable use is imperative.

The importance of well protected forests for the conservation genetics of West African colobine monkeys.

In tropical forests, anthropogenic activities are major drivers of the destruction and degradation of natural habitats, causing severe biodiversity loss. African colobine monkeys (Colobinae) are mainly folivore and strictly arboreal primates that require large forests to subsist, being among the most vulnerable of all nonhuman primates. The Western red colobus Piliocolobus badius and the King colobus Colobus polykomos inhabit highly fragmented West African forests, including the Cantanhez Forests National Park (CFNP) in Guinea-Bissau. Both species are also found in the largest and best-preserved West African forest-the Taï National Park (TNP) in Ivory Coast. Colobine monkeys are hunted for bushmeat in both protected areas, but these exhibit contrasting levels of forest fragmentation, thus offering an excellent opportunity to investigate the importance of well-preserved forests for the maintenance of evolutionary potential in these arboreal primates. We estimated genetic diversity, population structure, and demographic history by using microsatellite loci and mitochondrial DNA. We then compared the genetic patterns of the colobines from TNP with the ones previously obtained for CFNP and found contrasting genetic patterns. Contrary to the colobines from CFNP that showed very low genetic diversity and a strong population decline, the populations in TNP still maintain high levels of genetic diversity and we found no clear signal of population decrease in Western red colobus and a limited decrease in King colobus. These results suggest larger and historically more stable populations in TNP compared to CFNP. We cannot exclude the possibility that the demographic effects resulting from the recent increase of bushmeat hunting are not yet detectable in TNP using genetic data. Nevertheless, the fact that the TNP colobus populations are highly genetically diverse and maintain large effective population sizes suggests that well-preserved forests are crucial for the maintenance of populations, species, and probably for the evolutionary potential in colobines.

Fighting climate change with bamboo in Africa: The case of Kyela, Rungwe and Mufindi districts – Tanzania

Responding to the African Forest Landscape Restoration Initiative (AFR100), 32 countries have committed to restoring more than 100 million hectares of land across Africa by 2030. Bamboo is being discussed as one of the nature-based solutions to achieve this ambitious target in the face of climate change. Major advantages are that it is a fast-growing versatile woody grass that can prosper in degraded lands. So far, landscape restoration strategies are driven by climate policy debates where bamboo is largely neglected. Most empirical research on the potential of bamboo for fighting climate change has been conducted in Asia, leaving open questions on the transferability of results to the African context. In this paper, we contribute to the debate by investigating how bamboo can contribute to climate change mitigation, especially in degraded ecosystems. Taking Tanzania as an example, we lay a special focus on bamboo carbon sequestration and storage potential and assess the dynamics of carbon stocks: (i) across an elevation gradient, (ii) between indigenous and exotic bamboo species, and (iii) between intensively and extensively managed bamboo ecosystems. We collected data from 60 destructive sample plots and estimated biomass carbon stocks in the aboveground carbon pool. The weighted average biomass, carbon stocks, and sequestration rates obtained were 52.4 t ha−1, 26.2 t C ha−1, and 19 t C ha−1yr−1, respectively. The ANOVA revealed a significant variation in carbon stocks across an elevation gradient and between bamboo species (P < 0.05), which explained 22% and 11% of the total variation. We also observed a significant two-way-factors interaction between elevation versus species and silvicultural management options (P < 0.05), explaining 12% and 5% of the total variation, respectively. Similarly, a three-way interaction between all factors was significant, accounting for 4% of the total aboveground carbon variation. Our results contribute to developing a more nuanced picture of the advantages and disadvantages of incorporating bamboo in landscape restoration efforts. The novel findings may be a first step toward unlocking future climate finance in Africa.

Spatio-temporal analysis of North African forest cover dynamics using time series of vegetation indices – case of the Maamora forest (Morocco)

North African forest areas play several roles and functions and represent a heritage of great economic and ecological importance. As a result of global changes, that act independently or synergistically, these areas are currently undergoing a pronounced degradation and their productivity is decreasing due to several factors. This work aims to characterize spatio-temporal dynamics of vegetation within the Maamora forest. This forest is considered as the most extensive cork oak woodland in the world and is divided, from west to east, into five cantons A, B, C, D and E. The data, extracted between 2000–2021 from MODIS NDVI/EVI images of 250 m, were analyzed using statistical parameters with the Pettitt homogeneity and the Mann-Kendall trend tests, with their seasonal and spatial components, in order to better consider the vegetation distribution of this forest. Results show a clear temporal and spatial (inter-canton) variability of vegetation intensity, unrelated to the continental gradient. In fact, recorded mean values in cantons C and E are significantly higher than those of cantons B and D respectively. This is confirmed by both regressive and progressive trends, which were identified respectively from the months of March 2012 and October 2008, in the data series of cantons B and E successively. Spatially, the regressive dynamic remains generalized and affects more than 26.7% of the Maamora’s total area with extreme rates (46.1% and 14.0%) recorded respectively by the two aforementioned cantons. Similarly, all the stand types in canton B show the highest regressive rates, especially the cork oak regeneration strata (75.4%) and the bare lands (86.1%), which may explain the positive tendencies identified by the related series during the fall season. However, the cantons C and E record the lowest rates, respectively, for natural stands of cork oak and artificial plantations. These results highlight also the absence of a causal relationship between the contrasting vegetation dynamics of the Maamora and the climatic conditions, expressed here by the continental gradient. However, they do highlight the effects of other factors, particularly those of a technical nature.

Fá Divination, Well-being, and Coolness in Bénin, West Africa

Abstract For more than 40 years the relationships that exist between divination and knowledge have become central to anthropology’s understanding of African religious practice. This paper deemphasizes the commonly mobilized ‘divination as knowledge’ trope in favor of highlighting its role in achieving well-being. Indeed, I argue that by focusing on divination as a way of knowing ethnographers have inadvertently ignored what happens after said knowledge is acquired. It is these moments that I find to be at the heart of divination’s enduring value. Through an analysis of divination rituals, initiations, and material objects, alternative ways to examining divination in the West African rain forest are considered and explored. Looking to Fá divination, one of the major oracular systems employed by Fon speakers in the Republic of Bénin, I turn my attention to the ways in which divination helps individuals fulfill their destinies and achieve goodness in the world. In this way I argue that West African systems of divination are only secondarily about knowledge and first and foremost about achieving a sense of balance (coolness) and well-being.

Predictors of plant endemism in two west African forest hotspots

Centres of endemism have been much studied by biogeographers, ecologists, and evolutionary theorists, and are considered conservation priorities. It is therefore important to understand the ecological traits of restricted range taxa, and the landscape-scale drivers of high endemism. Here, we investigate correlates of floristic endemism within two of west Africa’s forest biodiversity hotspots at local scale. We assembled distribution data for 1,042 vascular plant taxa from 114 sample locations within forest reserves of south west Ghana, and for 1,735 vascular plant taxa from 454 sample locations within the Nimba Mountains (Liberia and Guinea). A quantitative index of global endemism called the Genetic Heat Index was modelled linearly. We tested the significance of modern climate, altitude and disturbance as factors predicting endemism rates in these two forest reserves. Annual rainfall was significantly and positively related to endemism rates in both south west Ghana and the Nimba Mountains. Altitude was a significant predictor of endemism rates in the Nimba Mountains, with a quadratic relationship highlighting particularly high endemism over 1,000 m. Local topography rather than altitude was a significant predictor or endemism in SW Ghana, where altitude varies less. Areas of high rainfall and high altitude are geographically restricted across the western African forests, acting as edaphic islands driving spatial isolation. Disturbed vegetation samples had lower endemism rates than undisturbed samples in both Nimba and SW Ghana, and overall pioneer species had wider areas of occupancy than shade-bearing species. Endemism rates increased slightly with each year following clearance. Disturbance thus creates and maintains vegetation types which support a lower proportion of globally rare species in the two biodiversity hotspots surveyed. From the point of view of the conservation of globally rare plants, it is important to keep additional disturbance in the south west Ghana hotspot, particularly Ankasa, to a minimum, as is the current practice, and in the Nimba mountains to establish community forests which may be left relatively undisturbed amid farming and mining activities.

Spatially explicit phylogeographical reconstruction sheds light on the history of the forest cover in the Congo Basin

AbstractAimThe impact of Pleistocene climatic oscillations on the biodiversity of African tropical rain forests remains poorly understood, and the Congo Basin is particularly understudied. We aim to elucidate how Pleistocene climatic oscillations shaped lowland tropical rain forests by investigating the intraspecific diversity and evolutionary history of a widespread tree species.LocationGuineo‐Congolian rain forest, Central Africa.TaxonStaudtia kamerunensis Warb. (Myristicaceae).MethodsWe used genome skimming combined with maximum likelihood and Bayesian inference to infer the plastid phylogeny. We estimated the time of speciation and differentiation, genetic diversity, and we employed a continuous phylogeographical approach to infer the dispersal history of its plastid lineages.ResultsWe sequenced an average of 5,827,783 reads per sample, and the reconstructed reference plastome had a mean depth of 73.3. We identified five plastid lineages that diverged during the Early or Middle Pleistocene and are parapatric, suggesting past population fragmentation. Four lineages are endemic to Lower Guinea, and one spans the Congo Basin. We found contrasting patterns of expansion in the two regions, with a rapid and recent range expansion of the Congolian lineage in the last 200,000 years, while the spread of the Lower Guinean lineages was substantially slower.Main conclusionThe contrasting demographic histories between eastern and western lineages, associated with contrasted levels of plant species richness and rates of endemism, suggest that forest cover was more stable in Lower Guinea during the Late Pleistocene than in Congolia, where the biodiversity might have been eroded before the forest re‐expanded in the Congo basin. This study illustrates how a continuous phylogeographical inference approach, mostly applied so far for inferring the spread of fast‐evolving pathogens over months or years, can provide new insights to reconstruct the dispersal history of tropical tree species over thousands or millions of years.

Forest landscape restoration in Ethiopia: Progress and challenges

The government of Ethiopia has made an ambitious plan of building a carbon-neutral and middle-income economy by 2030. In 2016, the country pledged to restore 15 million hectares of degraded landscapes as part of the African Forest Landscape Restoration Initiative (AFR 100). A total of three major forest landscape restoration (FLR) initiatives have been used to achieve this target: participatory forest management (PFM) to engage communities in sustainably managing natural forests; area enclosures/exclosures (AEs) to socially fence hillsides and degraded communal lands and allow these areas regain their productive potential; and sustainable land management program and the Green Legacy Initiative (SLM-GLI) that aim at conserving soil and water resources and planting seedlings to increase forest cover. After describing these FLR initiatives, this study evaluated their impacts on land use land cover change over time and assessed them against the six FLR principles by selecting nationally relevant criteria under each principle. The results showed that the FLR initiatives were rated rather low in terms of focusing on and managing landscapes for multiple benefits, in participation and benefits of stakeholders, in ownership and use rights, in employing approaches tailored to the local context, and in managing adaptively for long-term resilience. Concerning impacts, varying trends were observed for different areas, time periods, and restoration types. Recognizing and mitigating the limitations of these initiatives together with addressing site-specific drivers will improve the conservation and livelihood outcomes of FLR initiatives in Ethiopia. It is hoped that the findings of the study will inform FLR practitioners in other countries on the practical use of FLR principles in assessing the impacts of FLR initiatives.

Male and female songs propagation in a duetting tropical bird species in its preferred and secondary habitat.

Acoustic signals produced by animals must transmit through the environment to reach potential receivers and change their behaviour. Both the environment (vegetation, air properties, other animals) and the form of the signal affect the propagation process. Here we investigated how the transmission of different song types of a duetting songbird species inhabiting an extreme environment within African montane forest, varies between males and females as well as different types of micro-habitats. We hypothesised that male and female songs would have different transmission properties, reflecting known differences in signal form and function. We analysed signal-to-noise ratio (SNR), excess attenuation (EA) and tail-to-signal ratio (TSR) of songs of male and female Yellow-breasted Boubous (Laniarius atroflavus) that were played and re-recorded in a range of sites representing the species-typical habitats. We found significant effects of distance, site (habitat) and sex reflected in all three measures of sound degradation. The clearest, primarily distance-dependent pattern was found for SNR of songs propagated in level forest site. EA was substantially higher in shrubs than in forest habitats, while TSR reflecting longer echoes appeared at longer distances in forest sites. Thus, Yellow-breasted Boubou songs are better propagated in forests than in disturbed sites covered with shrubs. We found that all male song types used for broadcast singing propagated farther than female songs, with significantly higher SNR at all distances. The different male song types which are known to have different functions, also demonstrated a differentiated pattern of propagation reflecting their functionality. All signals that were tested propagated the furthest in the ideal condition described as forest with a level terrain. Signals degraded much faster during transmission through shrubs regrowing after forest burning. On this site, the differences in the propagation of male and female songs, as well as the differences between male song types, were relatively least pronounced. Transmission in typical mountain forest among streams and with substantial terrain variation revealed that degradation pattern in such habitat could be perturbed in a non-linear way. Streams acting as a source of high noise level also negatively affected transmission and may strongly limit the perception of birds staying close to them. However, stream noise did not affect sex differences in song propagation as was found for the site located in shrubs. Male songs showed more efficient transmission through all habitats (least in the shrubs) than female song. These differences were the result of male songs having a whistle structure that is better adapted for long-range propagation than the atonal, wideband frequency female vocalisations. Results support the idea that signals of males of the Yellow-breasted Boubous evolved under the pressure of long-range communication both with rivals and females, while females of the species are much more focused on within-pair communication or signalling together with their partner. The consequence of deforestation resulting in pushing back territories to the forest remnants along streams may be a shortening of the song’s active range, in particular, in females.

15. Africa

International funding remains essential in Africa. In this context, the resounding success at the international level of the Central African Forest Commission’s participation at the twenty-sixth Conference of the Parties to the United Nations Framework Convention on Climate Change, held in Glasgow, United Kingdom, from 31 October to 12 November, under the theme Uniting the World to Tackle Climate Change, ‘is historically unique and now worthy of celebration in many ways, not least because the intended Fair Deal alliance has become a reality and a start has been effectively made through donor engagement.’ This ‘Fair Deal’ means, on the one hand, good forest governance, and, on the other hand, fair payment for the ecosystem services of the Congo Basin forests in the Global Climate Budget. It recognizes the fair share of funding and political commitment to Congo Basin ecosystems, commensurate with their overall value in terms of biodiversity and carbon sinks.