This research aims to analyze the state of conservation of gazetted forest, community forest and sacred forest in the southern Benin. To do this, two gazetted forests, two communities forests and two sacred forests were chosen. The evaluation of the dynamics of the forest cover has been made of the comparative diachronic analysis of land cover in 1982 and 2015. The phytosociological and forest inventories were carried out in the forests studied. The results revealed that the areas of forest classes are held and sometimes experiencing an increase in the sacred forests while these forest classes experienced a regressive development in gazetted forests. In community forests, regression and maintaining forest classes were observed. The average density of trees is the highest recorded in the sacred forest of Zannouzoun (352.50 trees / ha) and the lowest density is achieved in the community forest Togbin-Daho (104.60 trees / ha). The highest Shannon diversity index is obtained in the sacred forest of Kodjizoun (3. 08 bits) while the lowest value of this index is recorded at the gazetted forests of Pahou (1.96 bit). The state and the evolutionary trend of forest cover and ecological parameters show that the sacred forests and incidentally community forests are best preserved as gazetted forests. However, the small size of sacred forests requires to qualify this conclusion.

The present study aims to analyze the hydropluviometric variability and the dynamic of land cover in the catchment of the Sota located at the North-east of Benin. It is based on the exploitation, on one hand, of rainfall and runoff data over the period 1965-2010 and, on the other hand, of satellite images Landsat TM of 1995 and Landsat 8 OLI/TIRS of 2013. The calculation of rainfall and hydrometric index and the application of statistical tests were used to analyze the hydropluviometric variability in the catchment of Sota. This variability is marked by similar fluctuations of rainfall and runoff. The break identified on rainfall and hydrometric series in 1970 is followed by a rainfall deficit of 6,76 % and a flow deficit of 33,75 %. The analysis of land cover maps produced from satellite images made it possible to release the land cover dynamic. This dynamic is characterized by the regression of natural vegetation formations to the profit of anthropic formations. The crops areas and fallows knew the greatest expansion with an annual growth rate of 6, 16 %. The degradation of the vegetation cover is undoubtedly one of the factors of the persistence of the relatively high level of the hydrometric deficit in the watershed of Sota.