Demissew Sebsebe (Professor)Bekele Tamrat (PhD)Tesfaw Binyam (PhD)Birhanu Liyew2021-03-102023-11-092021-03-102023-11-092020-06-02http://etd.aau.edu.et/handle/123456789/25374The rising of deforestation and habitat fragmentation due to the conversion of forests to other land use/ land cover types and the increasing human population are major environmental concerns in the northwestern dry Afromontane forest of Ethiopia. Understanding floristic diversity along environmental factors is essential in the management of the forest patches. The objective of the study is to investigate the Ecology of the vegetation and to study Land use/ Land cover change in Dega Damot district forest patches of Northwestern Ethiopia. Vegetation and environmental data were collected from 86 plots (30 m × 30 m). A total of 46 plots were used for the collection of the soil seed bank and aboveground vegetation. Soil samples were collected for the soil bank study from within the small plots measuring 10 cm × 10 cm from four soil layers. Shannon Weiner index and evenness were used to assess the species diversity and richness of the forest. The similarities between forest patches and between plant communities of the study area were computed using Sorenson’s similarity index. Density, Diameter at Breast Height ( DBH), basal area, frequency, and importance value indices (IVI) of woody species were computed to characterize the vegetation structure of the forest. Hierarchical cluster analysis and redundancy analysis (RDA) were used to identify plant communities and analyze the relationship between plant community types and environmental variables. This study used Landsat TM, Landsat ETM + and OLI data from 1986, 2003 and 2017 to map land use/land cover (LU/LC) in a study area. LU/LC maps were created using supervised classification, and LU/LC change the mapping for the 1986-2003 and the 2003-2017 period determined using post-classification comparisons. Results indicate the presence of 176 plant species belonging to 80 families. Asteraceae and Fabaceae were the dominant families, and herbs and shrubs were predominant growth forms. The Shannon diversity index and evenness values of the study area were 2.79 and 0.95 respectively. The total basal area and density of woody species were 51 m2 ha-1 and 2679 individual-1, respectively. The most dominant species as indicated by their important value index (lVI) were prunes africana(17), Schefflera abyssinica (15) and Ficus sur (14). Five plant community types were identified: Erica arborea - Osyris quadripartita, Discopodium penninervium - Echinops pappii, Olea europaeasubsp.cuspidata-Scolopia theifolia, Euphorbia abyssinica-Prunus africana, Dodonaea anguistifolia-Acokanthera schimperi. The RDA result showed that the variation of species distribution and plant community formation were significantly related to altitude, organic matter, moisture content, slope, pH, EC, clay and phosphorus. A total of 2133 seedlings belonging to 44 species and 27 families were identified from the soil seed bank, with a viable seed density of 4636 seeds/m2. The species composition of the seed bank was dominated by 29 herb species (66%) compared to 2 tree species which accounted for only 5 percent of the total number of species. The similarity between soil seed bank species composition and aboveground vegetation was low and conclude that the regeneration potential of the forest from seed bank was limited. The results of the study showed that agricultural land increased from 85% of the total area in 1986 to 93% in 2017. This increase coincided with a 4% decrease in a forested area, a 2% decrease in grazing land and a 2% decrease in shrubland. LU/LC was changed significantly due to rapid human populations and expanding agricultural activities in the study area. Therefore, this study provides baseline information for the conservation of forest in the study area.enFloristic CompositionHabitat FragmentationVegetation StructurePlant CommunitiesSoil Seed BankLand Use/ Land Cover ChangeThesis