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La présente étude permet de disposer de données spatiales sur les ceintures vertes villageoises (CVV) de la préfecture de l’Avé et d’apprécier leur dynamique dans le temps. Leur cartographie repose sur des techniques de digitalisation à partir de Google Earth pro. L’approche par télédétection a permis d’établir des cartes d’occupation du sol. Soixante CVV de taille variable ont été cartographiées puis catégorisées en trois groupes. Spatialement, elles se rencontrent plus au Nord. Entre 1985 et 2020, la dynamique des milieux artificiels est progressive alors que celle des milieux naturels est régressive. Quant aux trames vertes, les pressions sont freinées à cause des efforts de conservation. This study makes it possible to have spatial data on the village green belts (VGBs) of the prefecture of Avé and to assess their dynamics over time. Their cartography is based on digitization techniques from Google Earth pro. The remote sensing approach has made it possible to establish land use maps. Sixty VGBs of varying size were mapped and then categorized into three groups. Spatially, they meet further north. Between 1985 and 2020, the dynamics of artificial environments is progressive while that of natural environments is regressive. As for the greenways, the pressures are slowed down because of conservation efforts.

In Togo, the Oti-Keran-Mandouri (OKM) complex had important biological-oriented tourism activities in 1980s. However, degradation of ecosystems has negatively affected the biological resources of t...

This study aims to identify the drivers of environmental degradation due to the dependency of surrounding residents on three protected areas in Togo, Africa (Oti-Keran, Togodo, and Abdoulaye national parks (abbr. OTA national parks)). Surveys of villagers conducted in and around the OTA national parks added to data downloaded from Indexmundi data portal. National-level trend analysis results indicated: 1) the number of terrestrial protected areas showed an upward trend, while savannah and forest cover showed alarming decrease trends. 2) At the local level, supplying socio-economic needs in the three selected protected areas directly resulted in biodiversity degradation through animal grazing, hunting and farming. 3) Over 70% of the respondent’s livelihoods consisted of farming and related dependencies on the protected areas for timber and non-timber forest products and income despite the protected status hold by these classified areas. 4) The OTA national parks have been experiencing an increase of anthropogenic pressure such as uncontrolled tree logging and hunting, which seriously impacts animal and vegetation biodiversity. 5) Policymakers should invest more resources in implementing an integrated management system based not only on a holistic vision of the PA that includes participatory management but also accounts for multi-dimensional principles to enable anthropogenic activities in and around the protected areas to satisfy sustainable development requirements.

Macromycetes found on woody substrate (saprotrophic and ectomycorrhizal) of the university campus of Lomé in Togo are identified according to transect-plot method. A diversity of thirty-three (33) taxa of macroscopic fungi are identified up to genus level (sixteen taxa) and up to species level for seventeen taxa (17). Identified taxa included two (2) ectomycorrhizal species (Phlebopus sudanicus and Pisolithus tinctorius) and thirty-one (31) saprotrophs. The 32 taxa belong to the subdivision of Basidiomycotina. Ganoderma genus are represented by four species belonging to the family Ganodermataceae, which colonizes the greatest number of exotic wood substrates species (17) and local species (5). Azadirachta indica is the most colonized substrate by ten species of Macromycetes, followed by Delonix regia and Senna siamea colonized by nine and seven species respectively. According to the inventoried taxa, four species (Volvariella volvacea, Psathyrella tuberculata, Macrocybe lobayensis, Leucocoprinus cretatus) are edible mushroom and three (Ganoderma lucidum, G. colossus, Daldinia eschlosii) are therapeutic mushrooms. The subdivision of Ascomycotina is represented by only one species, Daldinia eschscholzii, of the order of Xylariales. Twenty-two (22) taxa of tree species representing woody host substrates of macromycetes are identified including eighteen Angiosperms (sixteen dicotyledons, two monocotyledons) and two gymnosperms (Cycas circinalis (Cycadophyte) and Pinus caribea (Coniferophyte)). The knowledge of macromycetes in this area subjected to a perpetual anthropic pressure for the establishment of infrastructures is therefore necessary, which will make it possible to have data on the diversity of this biological heritage before their eventual disappearance.

The application of remote sensing in understanding tree species structural diversity and land use patterns relationship is imperative for reforestation and biodiversity conservation efforts. This study assesses land use patterns and tree species structural diversity in previously reforested hilly sandstone regions of northern Togo. The physical height, and diameter at breast height (DBH) more than 5 cm of all tree species in each given plot were measured in summer 2017. A total of 75 plots of 900 m2 installed along the toposequence were recorded. In addition, a semi-supervised classification of Landsat 8 images in January of 2018, was also used to classify the land use patterns. 36 tree species and 19 families were recorded for the entire study area. Meanwhile, 19 tree species and 15 families were recorded for the previously afforested zones. The most abundant species included the Sterculiaceae, Zygophyllaceae, Meliaceae, and Mimosaceae. The trees stand structure represented 8.61 ± 0.57 m, 11.28 ± 1.76 cm, and 0.018 ± 0.009 m2 per hectare for height, diameter and basal area respectively. Major land use patterns were tree and shrub savannahs, parklands and croplands which represented over 60% of the landscape. It is necessary to examine the regeneration and vegetative multiplication potentials of the most frequent and abundant tree species for any eventual future afforestation programs in these hilly sandstone regions of northern Togo.

The rural landscapes in Central Togo are experiencing severe land degradation, including soil erosion. However, spatially distributed information has scarcely been produced to identify the effects of landscape pattern dynamics on ecosystem services, especially the soil erosion control. In addition, relevant information for sustainable land and soil conservation is still lacking at watershed level. On this basis, using the LAndscape Management and Planning Tool for the Mo River basin (LAMPT_Mo), we (1) modelled soil erosion patterns in relation with land use/cover change (LUCC), land protection regime, and landforms, and (2) examined the efficiency of landscape redesign options on soil erosion amounts at basin scale. We found that Simulated historical net soil loss (NSL) for the Mo basin were approximately 26, 23, 27, and 44t/ha/yr, for 1972, 1987, 2000, and 2014, respectively. These simulated NSLs were higher than the tolerable soil loss limits for the Tropics. Steep slopes (≥15°), poorly covered lands (croplands and savannas), and riversides (distances ≤100m) are critical areas of sediment sources. The local appraisal of soil loss was in line with the simulated outputs even though quantification was not accounted for when dealing with rural illiterate people. Furthermore, results showed that the examined management measures, such as controlling the identified erosion hotspots through land protective measures, could help reduce the NSL up to 70%, to values closer to the tolerable limits for the Tropics. The model implementation in the basin showed insights for identifying erosion hotspots and targeting soil conservation planning and landscape restoration measures.

An Ethnobotanical study of the species Khaya senegalensis was conducted in 2015 on Atacora mountains in the ecological zone II of Togo. Its general objective is to contribute to valorization of the species K. senegalensis and aims specifically to (i) evaluate the knowledge on the uses of the species and (ii) determine the interethnic convergence for uses of different parts of the species. The data collection is based on semi-structured ethnobotanical surveys by focus groups with 200 people from 5 ethnic groups. The parts of K. senegalensis used are bark, wood, leaves, and roots with bark being the most cited use (99.0%). These plant parts are used especially in traditional medicine for the treatment of 34 diseases and symptoms. The difference in average number of uses of the parts of the species is significant at the level of the ethnic groups (P = 0.000), age groups (P = 0.003) and gender (P = 0.040). The level of knowledge of the uses of the species is higher among ethnic groups Tem, Lamba, Kabyè and Tamberma. The study emphasizes the importance of ethnobotanical use value to improve sustainable management of this economically important species for its timber production.

L'étude caractérise les unités phytoécologiques des inselbergs granito-gneissiques du Sud-Est du Togo. La végétation a été décrite selon l'approche phytosociologique sigmatiste de BRAUN-BLANQUET. Sur chaque inselberg, des relevés floristiques (placettes de 100 m2 à 500 m2) ont été réalisés le long d'un transect joignant la pénéplaine au sommet. Chaque relevé est en outre caractérisé par des descripteurs écologiques. Les données collectées ont été encodées dans plusieurs matrices, adaptées aux formats des logiciels, en vue des traitements statistiques. La Detendred Correspondance Analysis (DCA), la Classification Ascendante Hiérarchique (CAH) et le Twinspan ont été appliqués aux relevés afin d'identifier les unités phytosociologiques et leurs caractéristiques écologiques. Les inventaires floristiques ont permis de relever 291 espèces appartenant à 223 genres et 79 familles dont les plus représentées sont les Fabaceae (38,0 %), les Poaceae (30,4 %) et les Rubiaceae (26,6 %). Les phanérophytes et les thérophytes sont les types biologiques les plus abondants. Les espèces guinéo-congolaises (18,1 %) et les espèces soudano-guinéennes (18,1 %) sont les types phytogéographiques prépondérants. Les espèces telles que Afrotrilepis pilosa et Cyanotis lanata représentent les angio-spermes endémiques ; mais l'étude a également révélé la présence d'une gymnosperme endémique (Encephalartos barteri). Six groupements végétaux ayant des physionomies de forêts sèches, de savanes, et de pelouses ont été identifiés. La distribution des formations végétales est liée à la profondeur des sols, en relation avec la position sur les inselbergs. The study characterizes the phytoecologic units of granito-gneissic inselbergs in south-eastern Togo. The vegetation has been described by the stigmatiste phytosociological approach of BRAUN-BLANQUET. On each inselberg, floristic samples (plots of 100 to 500 m2) were carried out along a transect joigning the peneplain to the summit. Each sample plot is also characterized by ecological descriptors. The collected data were coded in several matrices, according to the formats of the softwares, for the statistical processing. The Detendred Correspondence Analysis (DCA), the ascending hierarchical clustering (Classification Ascendante Hiérarchique ‒ CAH) and the Twinspan were applied to the samples in order to identify the phytosociological units and their ecological characteristics. Floristic inventories have identified 291 species belonging to 223 genera and 79 families mostly represented by Fabaceae (38.0 %), Poaceae (30.4 %) and Rubiaceae (26.6 %). The phanerophytes and therophytes are the most abundant biological types. The Guineo-Congolese species (18.1 %) and the Sudano-Guinean species (18.1 %) are the dominant phytogeographical types. The species such as Afrotrilepis pilosa and Cyanotis lanata represent the endemic angiosperms; but the study also revealed the presence of an endemic gymnosperm (Encephalartos barteri). Six plants groupings having aspects of dry forest, savannas and lawns were identified. The distribution of the plants grouping depends on soil depth, in relation with the position on the inselbergs.

In West Africa, accurate classification of land cover and land change remains a big challenge due to the patchy and heterogeneous nature of the landscape. Limited data availability, human resources and technical capacities, further exacerbate the challenge. The result is a region that is among the more understudied areas in the world, which in turn has resulted in a lack of appropriate information required for sustainable natural resources management. The objective of this paper is to explore open source software and easy-to-implement approaches to mapping and estimation of land change that are transferrable to local institutions to increase capacity in the region, and to provide updated information on the regional land surface dynamics. To achieve these objectives, stable land cover and land change between 2001 and 2013 in the Kara River Basin in Togo and Benin were mapped by direct multitemporal classification of Landsat data by parameterization and evaluation of two machine-learning algorithms. Areas of land cover and change were estimated by application of an unbiased estimator to sample data following international guidelines. A prerequisite for all tools and methods was implementation in an open source environment, and adherence to international guidelines for reporting land surface activities. Findings include a recommendation of the Random Forests algorithm as implemented in Orfeo Toolbox, and a stratified estimation protocol − all executed in the QGIS graphical use interface. It was found that despite an estimated reforestation of 10,0727 ± 3480 ha (95% confidence interval), the combined rate of forest and savannah loss amounted to 56,271 ± 9405 ha (representing a 16% loss of the forestlands present in 2001), resulting in a rather sharp net loss of forestlands in the study area. These dynamics had not been estimated prior to this study, and the results will provide useful information for decision making pertaining to natural resources management, land management planning, and the implementation of the United Nations Collaborative Programme on Reducing Emissions from Deforestation and Forest Degradation in Developing Countries (UN-REDD).

Dioscorea praehensilis Benth. constitue une importante igname dans certains pays de l’Afrique de l’ouest et du centre car elle y contribue a la securite alimentaire et a la reduction de la pauvrete. Au Togo, bien que cette espece soit cultivee a des fins de consommation par certaines populations locales depuis longtemps, elle demeure marginale. L’objectif de cette etude est d’inventorier la diversite de D. praehensilis cultive appele bayere dans la zone forestiere du Togo, d’analyser sa distribution, d’en documenter les valeurs socioculturelles, economiques, alimentaires et les pratiques paysannes de gestion. Pour ce faire des enquetes ethnobotaniques semi-structurees a l’echelle individuelle et celles de focus groupes ont ete conduites dans 34 localites aupres des producteurs de D. praehensilis et completees par des observations de terrains. Les donnees recueillies ont ete analysees par la statistique descriptive et les resultats presentes sous forme de tableaux et de figures. Selon la couleur du tubercule, les producteurs distinguent quatre types de bayere cultives a savoir le bayere « blanc », le bayere « noir », le bayere « jaune » et le bayere « rouge ». Ces bayere sont obtenus par transplantation et mise en culture d’individus sauvages dans les agroforets ou dans les jardins de case ou leur preservation lors de l’implantation des agroforets. Le bayere blanc est present chez tous les producteurs enquetes (100%) alors que les trois autres sont signales chez moins de 50% des enquetes. 45% des unites de production de bayere sont des jardins de case et 55% des agroforets. L’heritage (70%), le don (28%) et l’achat (1,2%) des semences assurent le maintien, la transmission et la diffusion des bayere et le bouturage la conservation de leur purete. Les qualites culinaires (100%), la productivite elevee (100%), la bonne regeneration (65%) sont les plus determinants dans le maintien des bayere. La faible valeur commerciale (34%), la recolte difficile (25%), le manque de semenceaux (23%), l’inadaptabilite aux zones seches (25%), le recul de la foret (24%), la perte des valeurs culturelles (20%), la scolarisation des jeunes (21%) sont les principales contraintes a la production des bayere et contribuent a la perte de leur diversite. Cette espece negligee fait partie du patrimoine economique, biologique, sociale, culturelle locale et dispose d’une potentialite non negligeable lui permettant de jouer un role important dans le maintien des moyens de subsistance, le bien-etre humain et l'amelioration de la sante. Mots cles: Igname, bayere, Dioscorea praehensilis , agrodiversite, gestion, valeurs, contraintes, conservation, sud- ouest Togo

This paper discusses the analysis and modelling of the hydrological system of the basin of the Kara River, a transboundary river in Togo and Benin, as a necessary step towards sustainable water resources management. The methodological approach integrates the use of discharge parameters, flow duration curves and the lumped conceptual model IHACRES. A Sobol sensitivity analysis is performed and the model is calibrated by applying the shuffled complex evolution algorithm. Results show that discharge generation in three nested catchments of the basin is affected by landscape physical characteristics. The IHACRES model adequately simulates the rainfall–runoff dynamics in the basin with a mean modified Nash-Sutcliffe efficiency measure of 0.6. Modelling results indicate that parameters controlling rainfall transformation to effective rainfall are more sensitive than those routing the streamflow. This study provides insights into understanding the catchment’s hydrological system. Nevertheless, further in...

In this study, historical landscape dynamics were investigated to (i) map the land use/cover types for the years 1972, 1987, 2000 and 2014; (ii) determine the types and processes of landscape dynamics; and (iii) assess the landscape fragmentation and habitat loss over time. Supervised classification of multi-temporal Landsat images was used through a pixel-based approach. Post–classification methods included systematic and random change detection, trajectories analysis and landscape fragmentation assessment. The overall accuracies (and Kappa statistics) were of 68.86% (0.63), 91.32% (0.79), 90.66% (0.88) and 91.88% (0.89) for 1972, 1987, 2000 and 2014, respectively. The spatio-temporal analyses indicated that forests, woodlands and savannahs dominated the landscapes during the four dates, though constant areal decreases were observed. The most important dynamic process was the decline of woodlands with an average annual net loss rate of–2%. Meanwhile, the most important land transformation occurred during the transition 2000–2014, due to anthropogenic pressures. Though the most important loss of vegetation greenness occurred in the unprotected areas, the overall analyses of change indicated a declining trend of land cover quality and an increasing landscape fragmentation. Sustainable conservation strategies should be promoted while focusing restoration attention on degraded lands and fragmented ecosystems in order to support rural livelihood and biodiversity conservation.

Quantification of carbon and nitrogen in soils in relation to ecological, landform and management factors over river basins is essential to understand landscape ecosystem functions and efforts to manage land restoration and the reduction of greenhouse gases emissions. Therefore, this research aimed at providing distribution of the potential storage in soil organic carbon (SOC) and total nitrogen (TN) within the multifunctional landscapes of the Mo river basin in Togo. We (1) quantified the potential storages of SOC and TN under different land use/cover types, landscape positions, and land management regimes; and (2) highlighted the relationships among these soil chemical properties, in-situ ecological conditions, and other hypothesized controlling factors. We used soil data from 75 sample sites to determine the quantity of SOC and TN at two depths (0–10 cm and 10–30 cm). In-situ ecological variables were collected simultaneously during soil sampling. Spatial information on biophysical conditions of the study sites were obtained from satellite images and most updated global topographic and soil databases. The results showed that SOC and TN varied significantly according to land cover types, soil depths, topographical positions and land protection regime. Generally, forests and woodland contain highest SOC (4%) and TN (0.3%). Agricultural fields (fallowed and cultivating farms) exhibited the lowest values of SOC and TN, except in some selected farm sites where these chemicals are still high. Topsoil layer (0–10 cm) contribute up to 60% of the total nutrient contents in soils. The sequential multivariate statistical approach unpacked and quantified the effects of inter-dependent ecological, management and landform drivers on the two important soil chemical properties (SOC and TN). The findings from this study could contribute to the improvement of national programme for assessing of greenhouse gases induced by land conversions. Based on this case-based finding in contextualization with related studies, we discussed on its implications for sustainable landscape restoration and climate change mitigation.

Nazinga Game Ranch (NGR) is a reserve in Burkina Faso involving local communities for securing biodiversity through sustainable management. Yet, its ecosystems are threatened by increasing number of elephants and illegal human activities. Renowned as a model of wildlife participatory management, NGR has mainly been studied for its animal wildlife only. The aim of this study was to uncover ecological effects of recent land management on savanna habitats including tourism, and to conclude on more sustainable options, land use/land cover (LULC) changes and vegetation dynamics in NGR were analyzed. This was accomplished with multi-temporal change detection using Landsat images of 1984, 2002 and 2013 to map seven representative LULC classification categories, and quantitative indices of landscape metrics. The results showed that the LULC dynamics in NGR from 1984 to 2013 was mainly characterized by an expansion of gallery forest, tree savanna and agricultural area and a reduction of shrub savanna, woodland and bare soils. From 2002 to 2013, fragmentation in all land cover types increased at the landscape level, whereas at the class level, it decreased for woodland. Our findings provided evidence of habitat degradation in NGR, due to extensive agriculture, tourism and growing of elephants’ population. According to the original management goals and the purposes of the reserve, both fauna and tourism are to be maintained and sustained in a sustainable way. Adaptation of land use and targeted wildlife management are the main requirements for avoiding further degradation of vegetation and thus of the existence basis of local inhabitants, animals and tourism.

Biodiversity conservation planning is highly important in the current context of global change. Biodiversity conservation can be achieved by understanding changes in land use at the landscape scale. Such understanding is needed to reverse the unprecedented pressure on natural resources that has been reported by many studies conducted on biodiversity conservation within the Oti-Keran-Mandouri protected areas. Land cover maps reflecting different dates (1987, 2000, and 2013) and depicting different management systems, with overall accuracy ranging from 73% to 79%, were analyzed to understand the processes that lead to habitat degradation within these protected areas. The nature of change, within a given land cover class, was determined by comparing land cover maps on different dates using a decision tree algorithm that compares the number of patches, their areas, and their perimeters at different time periods (T1 and T2). Specifically, two time-periods were considered for this analysis: 1987–2000 and 2000–2013. Croplands and settlements increased at an average of 108.13% and 5.45%, respectively, from 1987 to 2000. From 2000 to 2013, croplands gained from all other land categories and continued to increase at a rate of 11.77% per year, whereas forests and savannas decreased at an annual average rate by 5.79% and 2.32%, respectively. The dominant processes of habitat change from 1987 to 2000 were the creation of forests, dissection of savannas, attrition of wetlands, and creation of croplands. Meanwhile, from 2000 to 2013, there was attrition of forests, as well as attrition of savannas, dissection of wetlands, and aggregation of croplands. In general, from 1987 to 2013, natural habitats regressed and were replaced by croplands, forests, savannas, and wetlands decreased at an average annual percentage 5.74%, 3.94%, and 2.02%, respectively, whereas croplands increased at an average annual rate of 285.39% of their own area. Aggregation, attrition, dissection, and creation were the main habitat change processes identified for the overall period from 1987 to 2013. There was habitat loss in forests and savannas and habitat fragmentation in wetland due to attrition and dissection, respectively. Identifying and understanding habitat change processes would enable the taking of appropriate biodiversity conservation actions.

Le tourisme de vision dans les aires protegees est l’une des activites de valorisation et de gestion de ces ecosystemes. Cependant le tourisme d’observation de la grande faune peut contribuer a ternir l’image de l’aire protegee dans la mesure ou les circuits proposes a la clientele ne comblent pas ses attentes. Ainsi, des outils scientifiques permettant de disposer des informations fiables sur circuits touristiques d’une aire protegee peuvent contribuer a la planification fiable des activites ecotouristiques dans ces ecosystemes proteges. A cet effet, le present article presente une approche methodologique d’evaluation des capacites des circuits ecotouristiques d’une aire protegee, a repondre aux attentes des ecotouristes par rapport aux observations des grands et moyens mammiferes sauvages qui s’y trouvent. Dans cette approche, les parametres essentiels a considerer dans l’evaluation des circuits seront presentes. Il s’agit principalement de la probabilite d’observation, la diversite d’observation et la recurrence d’observation. L’application de cette approche methodologique dans le complexe Oti-Keran-Mandouri (OKM) a permis de constater que l’etat actuel de ce complexe est faiblement adapte pour la promotion du tourisme de vision des grands et moyens mammiferes.

In mountainous areas, biophysical settings and human disturbances strongly influence landscape patterns and dynamics requiring a permanent understanding of their combined influence. In this study, we investigated the diversity and patterns of wild landscapes in relation to ecological factors, human disturbances and land protection regime in the Mo river basin (Central Togo). First, we used geographical information systems (GIS) and remote sensing techniques to quantify and spatially explicit the major land cover types occurring in the area. We performed a supervised classification of Landsat 8 image from 2014. Next, we used vegetation ordination and classification methods to detect vegetation group types and their similarity level from forest inventory data collected at 75 sites. Data from soil samples at the 75 sites and DEM-based topographical indices were used as biophysical variables to analyze factors of current landscape structure. Both satellite image classification and the outputs from ordination methods indicated that three major vegetation types (forestlands, woodlands and savannahs/shrubs) occurred in protected (PA) and unprotected (UPA) areas. Image classification showed that savannahs/shrubs are the most widespread vegetation types (54.4%) while forestlands and woodlands cover 10.4% and 26.4% of the total area, respectively. UPA showed high rates of human disturbances that shaped the occurrence of a fourth vegetation type made up mainly by degraded savannahs and woodlands. Along the land protection gradient, the landscapes are driven by soil nutrients and moisture, in combination with the influence of topography and human disturbances. In both PA and UPA, and along protection gradient, majority of features exhibited significant differences among plant communities. The spatial analyses combined with the field data providing information on vegetation cover, species richness, and human footprint indices suggested that some areas outside protection still exhibit high potentials for land conservation. In multifunctional landscapes of Mo basin, conservation strategies could also be encouraged in the wild landscapes of community common lands to promote both biodiversity conservation and sustainable provision of ecosystem services.

In this study, land cover changes between 1972 and 2013 were investigated in the Binah River watershed (North of Togo and Benin) using remote sensing and geographic information system technologies. Multitemporal satellite images—Landsat MSS (1972), TM (1987), and OLI-TIRS (2013)—were processed using object-based image analysis and post–classification comparison methods including landscape metrics and changes trajectories analysis. Land cover maps referring to five main land cover classes, namely, agricultural land, forest land, savannah, settlements, and water bodies, were produced for each acquisition date. The overall accuracies were 76.64% (1972), 83.52% (1987), and 88.84% (2013) with respective Kappa statistics of 0.69, 0.78, and 0.86. The assessment of the spatiotemporal pattern of land cover changes indicates that savannah, the main vegetation type, has undergone the most dominant change, decreasing from 67% of the basin area in 1972 to 56% in 1987 and 33% in 2013. At the same time, agricultural land has significantly increased from 15% in 1972 to 24% in 1987 and 43% in 2013, while some proportions of agricultural land were converted to savannah relating to fallow agriculture. In total, more than 55% of the landscape experienced changes between 1972 and 2013. These changes are primarily due to human activities and population growth. In addition, agricultural activities significantly contributed to the increase in the number of patches, degree of division, and splitting index of forest and savannah vegetations and the decrease in their effective mesh sizes. These results indicate further fragmentation of forest and savannah vegetations between 1972 and 2013. Further research is needed to quantitatively evaluate the influences of individual factors of human activities and to separate these from the impacts of climate change-driven disturbances.

Vitellaria paradoxa (Gaertn C. F.), or shea tree, remains one of the most valuable trees for farmers in the Atacora district of northern Benin, where rural communities depend on shea products for both food and income. To optimize productivity and management of shea agroforestry systems, or "parklands," accurate and up-to-date data are needed. For this purpose, we monitored120 fruiting shea trees for two years under three land-use scenarios and different soil groups in Atacora, coupled with a farm household survey to elicit information on decision making and management practices. To examine the local pattern of shea tree productivity and relationships between morphological factors and yields, we used a randomized branch sampling method and applied a regression analysis to build a shea yield model based on dendrometric, soil and land-use variables. We also compared potential shea yields based on farm household socio-economic characteristics and management practices derived from the survey data. Soil and land-use variables were the most important determinants of shea fruit yield. In terms of land use, shea trees growing on farmland plots exhibited the highest yields (i.e., fruit quantity and mass) while trees growing on Lixisols performed better than those of the other soil group. Contrary to our expectations, dendrometric parameters had weak relationships with fruit yield regardless of land-use and soil group. There is an inter-annual variability in fruit yield in both soil groups and land-use type. In addition to observed inter-annual yield variability, there was a high degree of variability in production among individual shea trees. Furthermore, household socioeconomic characteristics such as road accessibility, landholding size, and gross annual income influence shea fruit yield. The use of fallow areas is an important land management practice in the study area that influences both conservation and shea yield.

The research was done in the Atacora Mountain chain in Togo which tended to assess the change of vegetation cover during a 24-year period. It also aims to evaluate the dynamic of the net primary productivity (NPP) of the living plants over the same period. The Landsat imagery covering three different periods (1987, 2000, and 2011) was pre-processed to correct atmospheric and radiometric parameters as well as gapfilling the 2011 SCL-off images. Then, the vegetation indices such as NDVI (normalized difference vegetation index), SR (simple ratio vegetation index), SAVI (soil-adjusted vegetation index), and CASA (carnegie- ames- stanford approach) model for NPP were applied on these images after masking the study area. The results showed a quiet decrease in the vegetation cover. The vegetation loss was more significant from 2000 to 2011 than from 1987 to 2000, and anthropogenic activities can be deemed as the main cause of the vegetation loss. The biomass assessment by NPP computation also showed a decrease over the time. Similar to the change of the vegetation cover, the ecosystem net productivity was very low in 2011 compared to 2000 and 1987. It seems that the general health condition of the vegetation, including its potentiality in carbon sinking, was negatively affected in this area, which has already been under threatened. A perpetual monitoring of these ecosystems by means of efficient techniques could enhance the sustainable management tools of in the framework of reducing emissions from deforestation and forest degradation (REDD).

Agricultural production in northern Benin is characterized by smallholder traditional agroforestry systems, with on-farm remnant tree species. Among its numerous advantages, agroforestry is known for its valuable contribution to biodiversity conservation. This study quantifies the importance of Vitellaria paradoxa C.F. Gaertn agroforests in terms of woody species conservation in Atacora district in Benin. Forest inventories were performed within 50×50 m plots constructed on a net grid map of Atacora district. Diversity indices were computed for both adult and juvenile species in two land management regimes: fields and fallows. Overall 41 woody species were recorded; 28 in fields and 36 in fallows. Taking into account matured and juvenile individuals, the diversity of woody species increased: 86 species in total; 69 species in fields and 78 in fallows. The biodiversity of V. paradoxa’s agroforestry parklands increases from fields to fallows, and decreases from bulk species (considering mature and juvenile species) to adult ones. Leguminosae and Combretaceae were the most abundant families registered. From the Cover Value Index, V. paradoxa, Parkia biglobosa, Lannea microcarpa, Lannea acida and Diospiros mespiliformis were the most abundant species. Support for maintaining this kind of agricultural system is needed, as this exemplifies the synergy for providing, provisioning and supporting services and biodiversity conservation. Key words: Agroforestry, conservation, ecosystem services, farmland, shea tree.

Vitellaria paradoxa (shea) parklands are one of the major features of the Sudanian savannah. Besides the parklands importance in terms of provision of ecosystem services, they play a major role in satisfying household subsistence needs. However, the shea trees on farms are under threat due to the increasing population growth, inappropriate agricultural practices and increasing effects of climate change. Thus, we examine the V. paradoxa population structure and its regeneration status in parklands under different land management regimes in four communes of Atacora department in Northern Benin. Dendrometric parameters were measured in five plots of 50 × 50 m in each commune and land management regime and the number of seedling and coppice were assessed. We applied Weibull theoretical model to compare measured and expected diameter classes’ densities. The tallest and largest individuals were recorded in fields while old fallows had the maximum tree density and regeneration across sites. In over-all, the tree densities across sites as well as regeneration were low in fields and young fallows. We also found that the land management regime significantly influenced regeneration particularly the coppices. On the other hand, the distribution of diameter classes showed that shea agroforests was represented by small diameter classes implying a stable and regenerating population in 92 % of visited sites, irrespective of the land management regime. Thus, the state of regeneration in shea parklands appeals for an improvement in the management of juveniles, a guaranty of future stable population.

International audience; Study region: The Kara River basin, northern Togo and Benin, West Africa. Study focus: This study investigated long-term trends in annual rainfall (annRAIN), annual rainfall duration (DURATION) and annual maximum rainfall (MAXAN) for seven stations between 1950 and 2010. A Bayesian trend analysis was performed by fitting the Lognormal, Normal and Generalized Extreme Value (GEV) distributions to annRAIN, DURATION and MAXAN, respectively, with a time covariate for both the location and scale parameters. Spatio-temporal variation of the mean decadal rainfall and the seasonality of the mean monthly rainfall were also analyzed. New hydrological insights for the region: The results indicate that the interannual variability of annRAIN is decreasing over time at all stations, and the average annRAIN is also markedly decreasing at several stations. However, DURATION is increasing at most stations suggesting that in those parts of the basin where annRAIN is decreasing, rainfall occurs more frequently but with less intensity. For MAXAN, evidence for decreasing trend is found in two stations, and for increasing trend in one station. It is also shown that the peak of the rainy season shifted from September to August since the 1980s. Furthermore, changes in the spatio-temporal distribution of the mean decadal rainfall are also observed. This study provides valuable new insights into trends affecting rainfall variables in the Kara River basin.

Remote-sensing data for protected areas in northern Togo, obtained in three different years (2007, 2000, and 1987), were used to assess and map changes in land cover and land use for this drought prone zone. The normalized difference vegetation index (NDVI) was applied to the images to map changes in vegetation. An unsupervised classification, followed by classes recoding, filtering, identifications, area computing and post-classification process were applied to the composite of the three years of NDVI images. Maximum likelihood classification was applied to the 2007 image (ETM+2007) using a supervised classification process. Seven vegetation classes were defined from training data sets. The seven classes included the following biomes: riparian forest, dry forest, flooded vegetation, wooded savanna, fallows, parkland, and water. For these classes, the overall accuracy and the overall kappa statistic for the classified map were 72.5% and 0.67, respectively. Data analyses indicated a great change in land resources; especially between 1987 and 2000 probably due to the impact of democratization process social, economic, and political disorder from 1990. Wide-scale loss of vegetation occurred during this period. However, areas of vegetation clearing and regrowth were more visible between 2000 and 2007. The main source of confusion in the contingency matrix was due to heterogeneity within certain classes. It could also be due to spectral homogeneity among the classes. This research provides a baseline for future ecological landscape research and for the next management program in the area.

L'elevage contribue a l'economie des populations locales dans les pays en developpement, mais reste tributaire de la disponibilite de la vegetation naturelle. Le but de cette etude est de caracteriser les formations vegetales pâturees (FVP) du bassin Mono. Un total de 63 parcelles d'echantillonnage realisees dans les communautes vegetales de la zone ont permis de recenser 311 especes reparties dans 58 familles et 204 genres. Cinq (05) types de pâturages discrimines sont faconnes par 22 determinants (topo-edaphiques, anthropogeniques et environnementaux). Le pâturage a Lonchocarpus sericeus et Diheteropogon amplectens (H '= 5,99) a l'indice de Shannon le plus eleve tandis que Mitragyna inermis et Cynodon dactylon pâturent l'indice le plus bas (1,51). Les groupes vegetaux etudies sont domines par les phanerophytes (43%) et les therophytes (34%). La flore fourragere est dominee par des graminees annuelles (37%), des graminees perennes (23%) et des graminees vivaces (12%). Les graminees moyennes et les legumineuses pauvres constituent la majeure partie de la flore fourragere de la zone. La regeneration naturelle des ligneux dans les aires de pâture est faible et est due aux impacts des determinants ecologiques et topo-edaphiques. Cette etude servira d'outil d'evaluation et de suivi de la biomasse des FVP dans ces ecosystemes. Mots cles : Biomasse, diversite, paysages pastoraux, caracterisation, regeneration, Togo.

Resume L’analyse de la problematique des plantes alimentaires mineures et menacees au Togo a pris en compte l’aspect distribution spatiale afin de mieux juger de l’ampleur de la menace. L’etude a ete menee sur la base des enquetes ethnobotaniques dans 280 localites distribuees sur toute l’etendue du territoire togolais. Au total, 137 especes alimentaires mineures et menacees de disparition au Togo ont ete inventoriees. Le nombre de plantes alimentaires en disparition varie de 2 a 40 suivant les localites et de 10 a 50 chez la plupart des ethnies. L’amplitude de leur distribution spatiale montre 20% des plantes signalees en regression sur l’etendue du territoire national. En revanche, 10%, 18% et 18% des plantes ont des distributions respectivement septentrionale, centrale et meridionale. Le reste des plantes presente des distributions interregionales. Ces differentes distributions traduisent des degres de menace qui dependent non seulement du nombre de citations de la plante, mais aussi de l’aire de distr...

These days, human activities in the savanna and the remaining dry and riparian forests of the Sudanian ecoregions continue to have their impact. These anthropogenic practices are still the main cause of disturbances in these areas. In order to investigate and assess the importance of these disturbances, caused by people bordering on protected areas and to determine the relation between these activities and the environment in which they are carried out, 220 samples were selected in the three main protected areas of northern Togo. The investigation was mainly qualitative, considering the floristic sampling of this drought area; any anthropogenic activities observed were recorded. A simple investigative questionnaire about the activities of rural people in the reserved areas was distributed to individuals encountered in the study area. Each sample in the investigation ended with a site description of its ecological characterization, i.e., soil features, topography, fauna footprints, dominant plant species and GPS position; we also took photographs of the site. Data processing was entirely based on descriptive statistics and a factor analysis. The results show that eight kinds of human activities, i.e., the use of pastures, tree cutting, bush fires, charcoal production, harvesting of plant material, farming, honey harvesting and hunting, were noted to be serious disturbances to the integrity of the ecosystems. Among these disturbances, three are recurrent in all the sampled areas of which the use of pastures accounts for 31.88%, tree cutting for 30.35% and bush fires for 30.13%. Fire and pasture disturbances are closely linked and are responsible for the current features of the savanna area of the region. Tree cutting is more a direct function of the need for the production of wood fuel, generally used by city populations. Hunting, farming and honey production are of lesser importance in the area and therefore, do not pose a significantly negative effect on the growth of fauna and flora. Knowledge of these disturbances in the context of requalification and a renewed demarcation of protected areas in Togo is essential for their sustainable management.

With some researches in Togo, the authors identify an unrecognized vegetal formation for tropical Africa, the tall herb formation, illustrated by the new Marantochloo purpureae—Anubiadetum giganteae, described by a phytosocio- logical table and family, biological, pollination and phytogeographical spectra. Some comparisons with other African tall herb communities allow to describe a new systematic structure, the S(Marantaceae-Commelinaceae).

(2010). La vegetation de la chaine de l'Atakora au Benin: diversite floristique, phytosociologie et impact humain. Acta Botanica Gallica: Vol. 157, No. 4, pp. 793-796.

In Africa, market gardening is often considered as a good solution to supply the crowded cities in vegetables. This intensive agriculture is very dynamic, but presents some dangers, as the non-qualified workforce manipulates delicate products: fertilizers and chemical pesticides. Even if the production quantity is good, its quality remains under doubt as pesticide treatments are uncontrolled. In Lome, market gardening is conducted by a young population of men, women and children who are poorly educated. Cultivated species are very diverse and the use of pesticides is widespread. Due to high pressure on land, cultivated areas are regressing which could lead, in the short term, to supply problems for Lome City.