Land use and land cover (LULC) change through inappropriate agricultural practices and high human and livestock population pressure have led to severe land degradation in the Ethiopian highlands. This has led to further degradation such as biodiversity loss, deforestation, and soil erosion. The study examined woody vegetation diversity status and the impact of drivers of change across different LULC types and agroecological zones in Gilgel Tekeze catchment, northern Ethiopian highlands. LULC dynamics were assessed using GIS techniques on 1976, 1986, and 2008 satellite images. Vegetation data were collected from 135 sample plots (20？m × 20？m) from five LULC types, namely, forest, shrub-bush, grazing, settlement, and cultivated land, in the three agroecological zones; Kolla, Weyna-Dega, and Dega. Differences in vegetation structure and composition and their relationship to agroecological zones were tested using two-way ANOVA and PCA technique. The results show that vegetation structure and composition significantly differed across all LULC types in different agroecological zones particularly in sapling density, tree height, and shrub height and in each agroecological zone between forest land, shrub-bush land, and settlement area. Overall, Weyna-Dega agroecological zone and the shrub-bush land had more structural and compositional diversity than the other agroecological zones and LULC types. 1. Introduction The Ethiopian highlands are subjected to important land degradation. Several studies have shown that there were significant land use and land cover changes in the Ethiopian highlands during the second half of the 20th century [1–6]. Most of these studies pointed out that rugged topography, inappropriate agricultural practices, and high human and livestock population pressure have been the main facilitators for the land degradation processes in the highlands [7–9]. Following the pressure on natural resources, the land use and land cover types are changing so rapidly. Around 19th century, about 40% of the land mass of Ethiopia was under forest cover but this figure had gone below 3% before two decades [10]. A study by Tekle and Hedlund [5] reported that open areas and settlements have increased at the expense of shrub land and forests in South Wello of north central highlands. Bewket [2] noted the problem of downstream sedimentation caused by upstream degradation, resulting from land use and land cover changes in the Chemoga watershed, north western highlands, and this has led to extensive flooding and damage on important agricultural lands. Serious
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