Marra Dourma

Satellite monitoring of land-use and land-cover changes in northern Togo protected areas

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.

Disturbance and Population StructureofPlant Communities in theWildlife Reserveof Oti-Mandouri in Togo (West Africa)

Aims: As a contribution to the sustainable management of protected areas in Togo, this study aims to analyze the impact of anthropogenic activities on plant communities in the wildlife reserve of Oti -Mandouri (North-Togo). Study Design:The study area is located in the Sudanian zone, in northeast Togo. Place and Duration of Study:The field work was carried out during April and June 2009, whilst processing data was done at Lab From July to October 2009. Methodology: Total height and stem diameter at breast height (dbh) greater than 10 cm of all trees species were measured in 126 plots. In each plot, ecological parameters were recorded and the seedling and suckers (dbh<10cm) of species were counted. Results:116 woody species with dbh greater than 10 cm belonging to 33 families and 84 Original ResearchArticle

Structure and Natural Regeneration of Sterculia setigera Del. Plants Communities in Sudanian Zone of Togo (West Africa)

Sterculia setigerais a multipurpose savanna tree with socio -economic importance due to its gum and cultural importance in sub -Saharan Africa.The present study was carried out in TogosSudanian area to characterize the structure and regeneration potential of S. Setigerain order to define a sustainable management plan associated to its valorization as gum species. Datawere collected during May and April 2010. The methodological approach was based on forest inventory oriented by the presence of S. Setigera. Total height and stem diameter at breast height (dbh) greater than 10 cm of all trees species were measured in 97 plots. In each plot, ecological parameters were recorded and the seedling and suckers (dbh<10cm) ofS. Setigerawere counted. Forty six woody species belonging to 42 genera and 22 families were listed. Fabaceae, Combretaceae, Malvaceae and Moraceae were the dominated families. The prominent species were S. Setigera, Balanites aegyptiaca,Lannea acidaand Diospyros mespiliformis. Presence/absence data of the overall species recorded in each plot was subjected to multidimensional scaling and results showed 5 plants communities: fallows, croplands, low side savannas, mean side and tablelands savannas and uplands savannas. The structure adjusted by 3

Distribution spatiale des plantes alimentaires mineures ou menacées de disparition au Togo: un indicateur de l’ampleur de leur menace

Résumé L’analyse de la problématique des plantes alimentaires mineures et menacées au Togo a pris en compte l’aspect distribution spatiale afin de mieux juger de l’ampleur de la menace. L’étude a été menée sur la base des enquêtes ethnobotaniques dans 280 localités distribuées sur toute l’étendue du territoire togolais. Au total, 137 espèces alimentaires mineures et menacées de disparition au Togo ont été inventoriées. Le nombre de plantes alimentaires en disparition varie de 2 à 40 suivant les localités et de 10 à 50 chez la plupart des ethnies. L’amplitude de leur distribution spatiale montre 20% des plantes signalées en régression sur l’étendue du territoire national. En revanche, 10%, 18% et 18% des plantes ont des distributions respectivement septentrionale, centrale et méridionale. Le reste des plantes présente des distributions interrégionales. Ces différentes distributions traduisent des degrés de menace qui dépendent non seulement du nombre de citations de la plante, mais aussi de l’aire de distribution naturelle de l’espèce.

La flore des forêts claires à Isoberlinia spp. en zone soudanienne au Togo Titre courant: Flore des forêts claires à Isoberlinia

Résumé Cet article est une contribution à une meilleure connaissance de la flore des forêts claires à Isoberlinia spp. en zone soudanienne au Togo. 508 espèces ligneuses et herbacées réparties en 315 genres et 79 familles ont été recensées sur 225 placeaux de 400 m². Trois nouvelles indications sont faites pour la flore de ces forêts (Thunbergia atacoriensis, Erythroxylum emarginatum, Chaetachme madagascariensis). Les phanérophytes, représentés par les espèces soudano-zambéziennes et de l’élément-base soudanien, sont les plus abondants. Les familles les plus représentées sont les Fabaceae, Poaceae, Rubiaceae, Asteraceae et Malvaceae. La variabilité des facteurs écologiques et l’anthropisation de la zone favorisent l’émergence d’espèces à large distribution géographique.

Régénération naturelle des peuplements à Isoberlinia spp. en zone soudanienne au Togo

Abstract Isoberlinia doka Craib & Stapf and I. tomentosa (Harms) Craib & Stapf natural regeneration is studied in the Sudanian zone of Togo on 74 plots (10 m ×10 m). The survey show that both species self—maintain by seedlings (32%), stump resprouts (10.6%) and root suckers (57.4%) in five types habitat (fields, fallows less than 5 years, fallows from 5 to 10 years, fallows more than 11 years forests). Suckering is the most important in fields and fallows. Root suckers and seedlings are more prone to regenerate the Isoberlinia woodlands than stump resprouts. Suckering is a low cost effective way to restore Isoberlinia forests especially in dry areas.