RETRACTED ARTICLE: Distribution and ecological impact of exotic woody plant species inside sacred groves of Northwestern Ethiopia

Abstract

The northern highlands of Ethiopia have undergone drastic forest loss and habitat degradation leaving fragmented small patches of sacred groves that have been threatened by land use changes including exotic plantation. The aim of this study was to examine the composition, distribution and impacts of exotic woody plants on vegetation dynamics inside church forests. To do these, 46 sacred groves were selected using stratified sampling based on elevation, forest size, wall, and their distance from towns. Vegetation data were collected in three transects using three compass directions. ANOVA was used to determine the effects of factors on the distribution of exotic woody plants and Regression analysis was also used to determine relationships between %exotic and vegetation dynamics. All data were analyzed using SAS in JMP-14 software. The study revealed that 38 (82.6%) out of 46 forests had exotic woody plants (924 exotic woody stems with 20 different species). The result also confirmed that sacred groves nearer to the towns, the absence of stone wall along the forest periphery and forests with high %human disturbance have high distribution of exotic woody species. These expansions of exotic woody plants 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 (vegetation) by substituting the existed multiple native plants. To preserve these sacred groves which are the remnant reservoirs of native plants from the exotic hazard, the traditional forest management techniques should be strengthened.