Research On Land Use Change, Vegetation Dynamic And Human Disturbances Of Protected Areas In Northern TOGO

Basic scientific research in Northern Togo protected areas is fundamental to ensure the sustainability of land resource management. Knowledge of the changes in land uses and present land cover is crucial to be able to determine which areas require more attention from conservation and restoration programs. Knowledge and better understanding of plant species distributions and influential environmental factors is important for the conservation and management of plant communities. Chorological analysis of plant species is helpful for understanding the factors determining the geographic range and particularly the role played by human in species introduction. Collection of tree data is important to understand their age structure. Assessment of the effects of human activities is necessary to plan the monitoring of protected ecosystems using the framework of sustainable management.Several purposes have guided the realization of this research. Among them the thesis aims firstly to present an analysis and interpretation of the changes of land cover and land use during the past20years using Landsat remote sensed satellite imagery. Then presents the vegetation of the three protected areas based on the phytosociology concept of Braun Blanquet and biodiversity analysis followed by the analysis of the woody vegetation of the three protected areas by using phytosociological methods, which aimed to understand the age distribution of trees and perennial species. And finally to evaluate the major human activities which affecting the vegetation integrity of the three protected areas in order to suggest recommendation for these areas management.For remote sensed data interpretation and analysis; based on the RGB-normalized difference vegetation index method with unsupervised classification, three Landsat images were analyzed to produce a land use change map. Supervised classification using the maximum likelihood classification technique was applied to the2007Landsat image to produce a land cover map. After the above method the floristic data collected were analyzed. In that regards the classification and description of the major plant community types based on species composition was applied to170samples. Detrended correspondence analyses of the samples found five main grouping along a moisture gradient. The clustering of a mosaic group ("G3") generated three subgroups. Indicator species of the seven major plant communities were determined by examining the indicator value. Clustering methods were applied to the matrix of species×samples generated from the data of a forest inventory to discriminate the main woody community per protected area. This step was followed by an ordination in direct gradient of samples and their floristic processing. The last part of methodology consist of the collection of data about human activities disturbances including their assessment by sampling using the land cover map previously got. After the analysis and interpretation of the batch of data the results were summary as mentioned below.Nine colors were used to represent the changes occurring in the three protected areas during the last20years, which included periods of vegetation harvesting, clearing, regrowth and stability. The changes were large in most of the ecosystems of the protected areas except for in the riparian forests. Despite difficulties in defining land cover and vegetation type in the three protected areas, seven land cover types were defined and the classification of the land cover map was satisfactory. The overall accuracy and kappa statistic was72.51%and0.67respectively. This chapter reveals the high anthropogenic pressure on these three protected areas, particularly Barkoissi that mostly comprised parkland and cropland. The findings also indicate that the riparian forests have the most conserved vegetation and are not subjected to as many disturbances as other ecosystems.In total,274plants species were recorded, belonging to247genera and63families. Chorological analysis confirmed that the area belongs to the tropical Sudanian zone; however, the influence of the Guineo-Congolian and Sudano-Congolian climates means that there is sufficient water availability for the establishment of forest ecosystems. This water availability results in a high abundance of phanerophytes and forest trees. Phytosociology and phytogeography were found to be complementary approaches that can describe the vegetation distribution and identify the factors affecting the distribution. Human activities were found to be associated with the introduction of alien species. In this study, I identified one species of concern, Strelitzia reginae Banks ex Aiton, which was new to Togo flora.In the three protected areas,12tree communities were identified based on an analysis of their floristic composition, and the indicator value was computed for each of them to determine their indicator species. Canonical correspondence analysis confirmed that the species distribution depends on water availability and human activities. The role of water availability is also shown by the presence of a cluster containing more lianas species, indicating the presence of wooded vegetation. Across the12woody plant communities, there were68plant species, belonging to47genera and25families. Most species were phanerophytes. The main phytogeographical type was Sudano-Zambezian. The area was dominated by shrubby savanna, which explains the small size of dendrometric parameters. However, the dendrometric parameters were smaller than those that evolve under the tropical Guinean climate. The high proportion of young individuals suggests there is natural regeneration of plant communities in the area.After preprocessing of the220samples, eight major land disturbance types were defined, which included pasture (31.88%), plant cutting (30.35%) and bush fire (30.13%) as the most important ones causing ecosystem degradation. Shrubby and wooded savanna areas were the most disturbed, which was recognized by local people. Human activities also affected the protected areas but their impacts on ecosystem integrity were interdependent. Some disturbance arose as a consequence of the socioeconomic activities of the local people.This study, in overall would be a baseline tool for planner and local developer at local or regional scale to sustaining the management of the PA especially in northern Togo, to plan or program (monitor) well the human activities in the ecosystem under high pressure and to achieve the project of consensual rehabilitation of PA (Northern Togo).