WOODY PLANT SPECIES DIVERSITY, ECOLOGY, AND ECOSYSTEM STATUS OF CHURCH FORESTS IN SOUTH GONDAR, NORTHWESTERN ETHIOPIA

AMARE, BITEW

dc.contributor.author	AMARE, BITEW
dc.date.accessioned	2019-12-18T05:23:07Z
dc.date.available	2019-12-18T05:23:07Z
dc.date.issued	2019-12-18
dc.identifier.uri	http://hdl.handle.net/123456789/10040
dc.description.abstract	The diversity and biomass of native vegetation in the central and northern highlands of Ethiopia is almost confined to sacred groves which are the only remnant natural forests in the region. However, these forests are under severe threats by anthropogenic disturbances. This study includes the woody species composition, regeneration status; soil nutrient dynamics, the amount of above-ground biomass (AGB), human disturbances, and impact of exotic species inside the forests. These all were also evaluated with respect to elevation, size, proximity to population, and the presence of stone wall surrounding the church forests. The study was conducted in South Gondar Zone, Amhara National Regional State, Ethiopia. Forty six church forests were selected for the study in stratified sampling based on the above factors. Vegetation and forest disturbance data were collected in 3 Gentry transects each 2 m wide in 3 compass directions i.e., 0°, 120° and 240°. All woody species >1cm DBH within each transect were identified, their DBH were measured and the disturbances were recorded. Seedling data were collected in three 1m2 seedling plots arranged from the inner to the edge of the forest in each of the three transects. Soil samples were collected from 10 m x10 m plots of the interior, middle and edge of each native forest, adjacent Eucalyptus plantations and outside the forest. Soil samples were homogenized and nutrients were extracted and measured. ANOVA and linear regression analysis were used to determine the effects of factors on woody species composition, soil nutrient dynamics, AGB, and exotic species distribution. All data were analyzed using SAS in JMP-14 software at α = 0.05 and t = 2.026. A total of 174 woody species belonging to 126 genera and 72 families were identified. Among these, 97(55.8%) were trees, 60(34.5%) shrubs, 6(3.4%) tree/shrubs and 11(6.3%) lianas. The most species-rich families were Fabaceae with 25 species followed by Euphorbiaceae with 9 species. The mean total woody stem density, woody species diversity and evenness from these 46 sacred groves were 4225 plants ha-1, 2.27 and 0.76, respectively. The regeneration potential of the church forests was fairly good. Soil nutrients and carbon decreased significantly from the interior to the outer edge of these forests. Eucalyptus plantations had significantly lowered the nutrient concentrations and the decomposition rate of soil organic matter than forest floor soil. The mean total of 542.34 ± 39.6 t ha−1 AGB was produced equivalent to 995.2 t ha−1 of CO2 sequestered in each 46 studied sacred groves. Species richness, density, and diversity of woody plants were positively correlated to biomass production. xvi Human disturbance was pervasive across all forests (56%). Edge effect and internal human disturbances were negatively associated with tree species richness, density, regeneration, and AGB. Among 46 forests 38(82.6%) had exotic woody plants (924 exotic woody stems with 20 different species). These expansions of exotic woody plant species significantly reduced the diversity, density, biomass and regeneration of native woody plants. The high demand for exotic trees like Eucalyptus for socio-economic importance may lead the sacred groves into mono-crop cultivation by substituting the native species. Keywords: Church forest; disturbance; Forest ecology; land-use change	en_US
dc.language.iso	en	en_US
dc.subject	BIOLOGY	en_US
dc.title	WOODY PLANT SPECIES DIVERSITY, ECOLOGY, AND ECOSYSTEM STATUS OF CHURCH FORESTS IN SOUTH GONDAR, NORTHWESTERN ETHIOPIA	en_US
dc.type	Thesis	en_US