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State of knowledge on duikers (genera Cephalophus and Philantomba) of central Africa rainforests. A review. Introduction. This article provides a synthesis of current knowledge on classification, ecology and biology of duikers living in central African rainforests (genera Cephalophus and Philantomba). It also provides an update on the anthropogenic pressures on these terrestrial mammals. Literature. Many publications on central African duikers are focused on subsistence or commercial hunting, and poaching. As the taxonomic classification of duikers has recently been revised, new species have been described with very little information available on their ecology. This synthesis highlights the gaps in the scientific knowledge and proposes priority themes for future research. Conclusions. Although many aspects remain to be explored for some species (i.e., habitat use, home range), it is suggested to investigate in priority: the inventory methods, the role of duikers in forest dynamics, and the impact of logging on their populations.

Developing a scientific journal in a changing world. After a brief historical review, this article presents the current situation of the journal BASE, its objectives, its challenges, its functioning and its limitations. BASE is a journal that publishes articles in Open Access in the field of agronomic sciences in the broad sense and offers a free service to authors. The editorial board pays particular attention to the transparency of its validation and editing processes. The figures presented allow BASE to find its place alongside all international scientific journals . At the end of the article, after describing the difficulties encountered, several perspectives are described. These should address the possible disadvantages of the multidisciplinary nature of BASE.

After a brief historical review, this article presents the current situation of the journal BASE, its objectives, its challenges, its functioning and its limitations. BASE is a journal that publishes articles in Open Access in the field of agronomic sciences in the broad sense and offers a free service to authors. The editorial board pays particular attention to the transparency of its validation and editing processes. The figures presented allow BASE to find its place alongside all international scientific journals . At the end of the article, after describing the difficulties encountered, several perspectives are described. These should address the possible disadvantages of the multidisciplinary nature of BASE.

Entandrophragma cylindricum (Sprague) Sprague (Meliaceae), a competitive tree species in Central Africa. A review. Introduction. Nowadays, the management of forest resources is no longer focused on the exclusive extraction of timber; it must also consider the use and management of non-timber forest products. Entandrophragma cylindricum (Sprague) Sprague, whose trade name is "sapelli/sapele", and which belongs to the Meliaceae family, perfectly illustrates this issue. This article proposes an overview of the existing literature regarding E. cylindricum and presents some information on its host caterpillar. Literature. Sapele is among the most exploited tree species in Central Africa, due to its valuable timber. This tree is common in the semi-deciduous rainforest of the Guinean–Congolese domain. It is a non-pioneer, light-demanding species, its dispersal mode is anemochorous and the phenology is regular. Logging coupled with thinning boosts the diametric growth of individuals by up to 0.82 cm·year-1. Sapele is also the host of an edible caterpillar species that is rich in protein, Imbrasia oyemensis Rougeot. Highly appreciated by the local populations, this caterpillar is sought out for regional and international trade purposes. In addition, the bark of the sapele is renowned for its ethnobotanical properties, especially in traditional medicine. Conclusions. The information reviewed from the literature helped to highlight some gaps in the knowledge regarding the reproductive ecology of this species, despite its importance for the timber trade. In addition, the current lack of information regarding the productivity and the seasonality of caterpillars of I. oyemensis inhabiting this tree requires the development of complementary research to ensure the sustainability of timber and non-timber uses for sapele. In addition, it is important that such improved silvicultural techniques involve concerted management interventions between logging companies and the local populations.

Drivers of deforestation in the Congo basin tropical forest. A review. Description of the subject. The forests of the Congo Basin are among the best preserved areas on Earth. Nevertheless, the factors causing deforestation around the world are also present in this subregion. This document presents a literature review of the direct causes and underlying factors of deforestation in the tropical areas and highlights the drivers of deforestation in the Congo Basin and particularly in Cameroon and Gabon. Literature. Direct causes of deforestation, defined as having a direct cause-and-consequence connection with the destruction of forest cover, are underpinned by economic factors, technological developments, pro-deforestation policy measures and demographic pressures. These factors interact in different ways in the various tropical regions worldwide, which explains the differences and similarities of regional deforestation dynamics. Beside the expansion of infrastructure, the development of mining and timber extraction, agriculture is the main direct cause of deforestation in the Congo Basin. In Cameroon, the current deforestation is primarily driven by agriculture. The State emergency plan includes the development of infrastructure, the modernization of production, equipment and mining. The lack of strategy for rapidly changing demographics might be the most important underlying cause of deforestation. In Gabon, although the deforestation rate is low, agriculture and the opening of roads are main drivers. The emergency plan includes modernization of infrastructure and the development of agro-industrial agriculture. Conclusions. A mutation of socio-ecosystems is expected in different parts of the Congo Basin. Future research should now turn to the analysis of socio-ecosystems representative of the various stages of the forest transition and identify drivers of change at different scales.

The Sahamalaza National Park - Radama Island may be the last Shelter for some Species of Lemurs of North-west Madagascar?. Most of the plant and animal species found in Madagascar have evolved in long isolation over the millennia. The level of endemism is very high and the island is one of the most important biodiversity hotspots on the planet. But Madagascar is also one of the world's most heavily impacted countries in terms of habitat destruction; 90% of the original vegetation has already been lost. The endemic primates of the island, the lemurs, are particularly affected by continuous deforestation and forest fragmentation. The island is considered by many international organizations as a priority for nature conservation. The first protected area was created in Madagascar in 1927 and the island has now a total of 47 protected areas. This paper recalls the history and the current status of the Sahamalaza – Radama islands National Park, located in northwest Madagascar. We focus particularly on two emblematic species of lemurians for the park; Eulemur flavifrons and Lepilemur sahamalazensis, as well as on the existing threats on the ecosystems. Several measures have been proposed in the Conservation Action Plan in order to improve the management of the park and long term survival of the species.

Importance of Coula edulis Baill. for the People of South-East Gabon: Harvest Levels and Economic Potential. Coula edulis is a non-timber forest tree species that provides edible fruits for local people. However, its economical importance has never been quantified. The present study aimed to identify the fate of stocks of harvested C. edulis fruits in Gabonese villages, emphasizing the social impact and economic income generated by this activity. Our investigations revealed that C. edulis fruits are predominantly utilized for own subsistence, since trading proportion concerned less than 20% of collected fruits. The average income from trade during the harvest period (two months) varied from € 1.7 to € 3.3 per household, depending on the proximity of the market (local or urban). The economical potential of C. edulis fruits could be improved if a sustainable production strategy through domestication processes and agroforestry practices was developed. Such a strategy may also contribute to the increase of the local demand of C. edulis fruits, assuming that a better diffusion was also carried out.

Valuation of Wood Residues from Artisanal Logging of Community Forests in Cameroon: Case Study of the Community Forest of Mambioko (GIC CRVC). Artisanal logging of wood from community forests generates important amounts of wood residues in logging sites. The value of these wood pieces could be enhanced in marketable commodities in order to improve the benefits of the community. This study gives a first estimation of the volume of wood residues and proposes various valorization methods appropriate to the community of Mambioko. This article is directed at all stakeholders of the Cameroonian community forestry and aims at a rational valorization of woody material for rural development purposes.

Consumption of Products of Animal Origin in the Forest Concession 039/11 of the SODEFOR to Oshwe (D.R. Congo). To identify the main foods of animal origin consumed by people living in the concession 039/11 of the forest Development Company (SODEFOR) in the Democratic Republic of the Congo, and to specify the determinants of consumption, 120 households in 3 villages (Taketa, Ikala 1 and Mombele) and in the base of Nteno were surveyed for 30 days. The results show that bush meat represents 72.00% of the number of meals followed by fish (24.00%), and livestock products finally (3.10%). In total, 30 species of animals including 4 which are legally banned from hunting have been identified, for a total biomass of 1235 kg. Mammals represent 97.00% of animals consumed with a predominance of artiodactyls (71.60%), primates (15.40%), and rodents (9.10%). The duikers, the bushes and the atherure are the most represented. The choice of consumption is guided by the availability of the product, taste, and eating habits. The majority of households are supplied by intermediaries to whom they primarily buy animal parts. This study suggests a long term follow-up of hunting with an assessment of the abundance of animal species to guide the SODEFOR in the decision-making.

As human threats continue to impact natural habitats, there is an increasing need to regularly monitor the trends in large vertebrate populations. Conservation efforts must be directed appropriately, but field work necessary for data collection is often limited by time and availability of people. Camera traps are used as an efficient method to insure continuous sampling and to work in difficult to access areas. In the present study, we illustrate how this instrument is serving a diverse field of studies, such as animal behavior, population monitoring and fauna-flora interaction. By looking at the material and technical aspects of various models of camera trap for implementation in different field studies in animal ecology, we highlight the need to choose appropriate camera trap models for the target species and to set up solid sampling protocols to successfully achieve study objectives.

Introduction. Madagascar is one of the highest biodiversity hotspots on the planet; however, it is also one of the most heavily impacted countries in the world in terms of forest degradation and general habitat destruction. Literature. Genus Lepilemur, in family Lepilemuridae, is a genus of small, nocturnal, exclusively arboreal Malagasy folivores. All species in the genus have small ranges of distribution. Fully forest-dependent, they have a high risk of extinction. Various models and theories of speciation mechanisms have been developed for the fauna and flora of Madagascar. For instance, in the northwestern part of the island, some authors used Lepilemur spp. to test two existing models of distribution: the "Martin model" and "Wilmé model". Conclusion. Regarding the impact of forest destruction and habitat degradation in Madagascar, conservation strategies for Lepilemur need to be put in place. This paper gives an overview of the current knowledge of the genus Lepilemur and examines speciation for Malagasy lemurs. The understanding of species distribution within biodiversity hotspots is important to identify target for conservation. Therefore, we summarize and compare three biogeography models related to lemurs distribution in order to understand the reasons behind the high diversity (26 species in total) among the genus Lepilemur. Particular attention is also given to the concept of species regarding biodiversity issues and the taxonomic explosion in genus Lepilemur.

Due to the paucity of suitable habitat, hippos are very rare in the Congo Bassin. Compared to East-African populations, Central African populations of hippos have been less studied. Information found in the literature regarding the animal's basic ecology is limited. This study focuses on the description of the diet of an isolated hippo population in Loango National Park (Gabon), comparing faecal analysis with a reference collection of herbaceous species from the savannas. The effectiveness of using faecal analysis versus using the floristic description of hippos' pastures was demonstrated. The most frequent herbaceous species identified in faeces samples were Paspalum vaginatum, Axonopus compressus, Stenotaphrum secundatum (Poaceae) and Desmodium triflorum (Fabaceae). The voluntary consumption of a dicotyledonous species (Desmodium triflorum) is novel for this species.

The comparison of some elephants count methods – aerial sampling count, aerial total count and direct foot count – has been presented through surveys' study cases implemented in Benin, Burkina Faso and Niger. We compare them in terms of effort and cost to survey an area (sampling efficiency), efficiency in data collection (detection efficiency) as well as accuracy and precision. Aerial sampling count returns low sampling and detection efficiency and very low precision and accuracy figures when counting elephants populations below 0.5 elephant·km-2. Precision can partly be improved by stratification. Direct foot count returns the best sampling and detection efficiency but insufficient data number to produce reliable estimates. Therefore some authors often produced no results for elephants. Aerial total count is a costly method in absolute value. It requires important logistic and no measure of error is possible. However it provides relatively good sampling and detection efficiency as well as relatively accurate figures appreciated by wildlife managers if technical requirements are respected. Aerial total count could be recommended to survey small population of West African elephants each 3 to 5 years to minimize yearly count costs.

The present study consists of analyzing the raw data collected from the annual line-transect foot count of medium-sized ungulates, carried out at the Nazinga Game Ranch (NGR), Burkina Faso (Western Africa), in both 2001 and 2010. The annual census focused on the seven main medium-sized ungulates, namely (in alphabetical order), the Bushbuck (Tragelaphus scriptus), the Common Warthog (Phacochoerus africanus), the Defassa Waterbuck (Kobus ellipsiprymnus), the Grimm's Duiker (Sylvicapra grimmia), the Oribi (Ourebia ourebi), the Roan Antelope (Hippotragus equinus) and the Western Hartebeest (Alcelaphus buselaphus). The census also focused on illegal anthropogenic activities. The wildlife populations were quantitatively analyzed through an estimation of their absolute density via the distance sampling method and through their evolution over the last decade using two relative density indexes, namely the Kilometric Abundance Index (KAI) and a spatial distribution index. These indexes were also used to measure the evolution of illegal activities over the same period. Both the wildlife observations and the anthropogenic observations were mapped using the Kernel method. Following an increasing trend in their population between 2001 and 2010, both the Roan Antelope and the Western Hartebeest reached an estimated density of 4.7 individuals per km², while the Defassa Waterbuck reached 2.4 individuals per km². Following an inverse trend over the same period, the Bushbuck, the Grimm's Duiker and the Oribi reached an estimated density of 0.4 individuals per km². As for the Common Warthog, its estimated density of 2.5 individuals per km² seemed to remain unchanged during that decade. A comparison between wildlife observations and anthropogenic observations reveals a high decrease in animal densities in the north, east and west peripheral borders of the NGR and a flagrant extension of the proportion of the ranch being subjected to illegal activities (poaching, cattle herding, etc.).

African walnut (Coula edulis Baill.). An unknown non-timber forest product. Non-timber forest products (NTFPs) are of significant nutritional, economic and cultural importance for the people of central Africa. However, many products have not yet been the subject of scientific studies; such is the case of Coula edulis. Although very little is known about this species, it has many uses and its fruits are regularly eaten and marketed by various communities. Cultivation of this tree species remains however very limited, mainly because of the low germination potential of its seeds. Its wood, renowned for its termite resistance, is used locally for construction. Mechanical tests conducted on the timber have put its technological aptitudes to the fore; it has indeed the potential to become one of the most sought-after commercial species. As in the future, Coula edulis could be managed for its wood as well as its non timber products, in-depth studies aiming at the sustainable development of this natural resource need to be implemented.

Land issues, exploitation of natural resources, and Forests of Rural Communities in the periphery of Kinshasa, DRC. Peri-urban forests are under strong anthropic pressure. Any activity needs a previous identification of stakeholders, landscape perception, socio-economic trends in local communities and their relationships with land and natural resources. Kinshasa (capital of Democratic Republic of Congo, DRC) is a 10 millions inhabitants city with rapid growth and increasing impacts on surrounding villages linked with forest natural resources. This paper describes the relationship amongst local communities stakeholders and their relations with land areas and wood resources. Two areas surrounding Kinshasa (Bas-Congo and Bateke Plateaux) are considered as major fuel-wood and charcoal supply zones for the city. Those two areas are different in terms of land pressure (very high in Bas-Congo and focused on riparian forests on Bateke Plateaux), but show the same pattern of overuse of the forest and woody natural resources. In both areas, local management of forest resources by the traditional authorities (heads of village or lineage) has failed. Local population willingness for reforestation and forest restoration activities is much more important in Bas-Congo than on Bateke Plateaux. In both areas, shifting cultivation due to slash and burn practices for agricultural and charcoal practices are more and more quick. This has strong negative impact on the potential of regeneration process with local forest species. Sustainability of forest natural resources management by communities is discussed in regard to the on going negotiations on community based forest management regulations.

Conservation and Anthropization in Central Africa. As we enter a millennium often referred to as Anthropocene, with reference to the influence never before seen in the history of a species namely the human being, world biodiversity declines at an accelerated pace. A pace of change so severe that researchers have difficulties describing the current phenomena. Wildlife in particular is seriously threatened, to such an extent that we speak about the biggest massive extinction of animal species ever to occur on Earth. Many regions of the globe, in particular Central Africa, thus see theirbiodiversity disappearing before it is even documented. With regard to its concerns about the sustainability of the environment, the journal Tropicultura now opens its columns to authors working in conservation and the relations between man and nature, and more particularly its wildlife. Stemming from a call for contributions directed at young active researchers in Central.Africa, this special issue is as diverse as the themes developed in conservation of this region. >From plains Gorillas of Cameroon to bushmeat consumption in Gabon and the participative management in Congo, intrepid scientists offer us an anthology of fascinating stories. Scattered at the edge of dense forests, in remote and sometimes dangerous areas, these researchers raise numerous questions about the future of wildlife in this part of the globe. A frightening future, since the threats seem more numerous than the solutions. Nevertheless, these articles also deliver a positive vision of the situation. They demonstrate the will of enthusiast conservationists to fight relentlessly for the preservation of our ecosystems. They also demonstrate the increasing implication of researchers from those regions to protect their incredible heritage and reconcile man and nature. If figures are disturbing and human population grows and expands perpetually, particularly in these countries, the interest for environmental protection was never so important in our society as it is at the moment. Through their research, these young scientists offer potential solutions by demonstrating to what extent man is connected to this biodiversity and dependant upon it for his survival.By increasing the awareness of this dynamic, we dearly hope to mitigate the harm and facilitate a more accomodating future for the incredible natural resources of our planet. Let us appreciate that this publication would not have come about without the help of many renowned scientists, who agreed to make the selection and the review of the articles. We wish to specifically thank the following individuals :E. Arnhem (WCS), S. Carriere (IRD), N. Gami (ECOFAC V/RAPAC), B. Haurez (ULg/Gembloux), M.-C. Huynen (ULg), C. Julve (Nature+), J. Punga Kumanenge (Université de Kinshasa), C. Vermeulen (ULg/Gembloux)and J. Willie (Royal Zoological Society of Antwerp).

Background: A number of accelerator-based isotope production facilities utilize 100- to 200-MeV proton beams due to the high production rates enabled by high-intensity beam capabilities and the greater diversity of isotope production brought on by the long range of high-energy protons. However, nuclear reaction modeling at these energies can be challenging because of the interplay between different reaction modes and a lack of existing guiding cross-section data. Purpose: A Tri-lab collaboration has been formed among the Lawrence Berkeley, Los Alamos, and Brookhaven National Laboratories to address these complexities by characterizing charged-particle nuclear reactions relevant to the production of established and novel radioisotopes. Method: In the inaugural collaboration experiments, stacked-targets of niobium foils were irradiated at the Brookhaven Linac Isotope Producer (Ep=200MeV) and the Los Alamos Isotope Production Facility (Ep=100MeV) to measure Nb93(p,x) cross sections between 50 and 200 MeV. First measurements of the Nb93(p,4n)Mo90 beam monitor reaction beyond 100 MeV are reported in this work, as part of the broadest energy-spanning dataset for the reaction to date. Nb93(p,x) production cross sections are additionally reported for 22 other measured residual products. The measured cross-section results were compared with literature data as well as the default calculations of the nuclear model codes TALYS, CoH, EMPIRE, and ALICE. Results: The default code predictions largely failed to reproduce the measurements, with consistent underestimation of the preequilibrium emission. Therefore, we developed a standardized procedure that determines the reaction model parameters that best reproduce the most prominent reaction channels in a physically justifiable manner. The primary focus of the procedure was to determine the best parametrization for the preequilibrium two-component exciton model via a comparison to the energy-dependent Nb93(p,x) data, as well as previously published La139(p,x) cross sections. Conclusions: This modeling study revealed a trend toward a relative decrease for internal transition rates at intermediate proton energies (Ep=20-60 MeV) in the current exciton model as compared to the default values. The results of this work are instrumental for the planning, execution, and analysis essential to isotope production.