Woody species composition and community types of Hangadi Watershed, Guji Zone, Ethiopia

Background Hangadi watershed is endowed with the only virgin forest in Odo shakisso harbouring high biodiversity, but it has been suffered from anthropogenic activities. This study was conducted to investigate composition and community diversity of woody species in restoration for posterity. Satellite images of 1988, 2008, and 2018 were used to classify and analyse trends of deforestation. For both woody species and topsoil (0–30 cm), 20 m × 20 m, 100 plots laid at every 300 m along line transects, 1 km apart from each other. In each sample plot, woody species ≥ 3 m were counted, Shannon–wiener diversity index, cluster analysis and ordination were computed. Results Agroforestry is found to be the dominant land use/land cover class followed by forest and cultivated land. A total of 61 woody species belonging to 34 families; 8.2% of the species were endemic to Ethiopia. The highest number of species was recorded from families Euphorbiaceae and Rubiaceae (5 species, 8.2%), Rutaceae, Celastraceae, and Oleaceae (3 species, 5.08%) followed by Flacourtiaceae, Meliaceae, Araliaceaae, Myrsinaceae, Moraceae, Boraginaceae, Asteraceae, Spontaceae, Lauraceae and Sapindaceae (2 species each). Four woody plant communities were identified using free statistical software R version 3.1.1. The canonical correspondence analysis result showed that EC, pH, OM, altitude, C:N, CEC, sand, silt, AvP, and TN significantly affected species distribution in the watershed. Conclusion Local people involved in cutting mature woody species for timber production, making farm implements and, cultivated land expansion. Protection of woody species diversity of forest and coffee systems with low biodiversity value conservation concepts are recommended to be executed jointly by local people and stakeholders.

Conversion of natural forests to farmlands and its associated woody species diversity and carbon stocks in a span of 33 years (1984 to 2016): in the case of southwestern Ethiopia

Background Gura-Ferda forest is one of the Afromontane rainforests in the southwestern region of Ethiopia. However, since 1984, large parts of this forest have become increasingly disturbed and fragmented due to forest conversion into forest farm interface and farmlands. The study was conducted to assess changes of woody species diversity and carbon stock in association with the conversion of natural forest to forest farm interface and farmlands. Methods Data were collected from natural forest, forest farm interface and farmland which are historically forest lands before 1984. A total of 90 nested plots (20m×20m for natural forest and forest farm interface; 50m*100m for farmland)) were established for inventory of woody species. Three 1m×1m subplots were established to collect litter and soil samples. A total of 180 soil samples were collected. The total carbon stocks were estimated by summing carbon stock in the biomass and soil (0-60 cm depth). Results Results showed that Shannon-Wiener diversity (H’) in forest farm interface (H’ = 1.42±0.49) is significantly lower than that of natural forest (H’ = 2.72±0.31) but significantly higher than farmland (H’ = 1.08±0.57). The total carbon stocks of natural forest (388.54±161.63 Mg C ha-1) were approximately 1.53 and 2.67 times higher than that of forest farm interface (252.95±41.86 Mg C ha-1) and farmland (145.58±25.94 Mg C ha-1). Conclusion Our study revealed that along the conversion gradient of natural forest to forest farm interface and farmland there was a significant change of woody species diversity and carbon stocks.

COMPARISON OF WOODY SPECIES DIVERSITY AND POPULATION STRUCTURE STATUS ACROSS DIFFERENT MANAGEMENT PRACTICE IN THE GOLA NATURAL VEGETATION, EASTER HARARGHE, OROMIA OF ETHIOPIA

The research was carried out at Gola natural vegetation eastern Ethiopia, to identify and Woody species' diversity, richness, evenness, and population structural status will be documented, as well as their diversity, richness, evenness, and population structural status will be analyzed. Using systematic sampling procedures, the woody species diversity and population structure of species were examined in 73 quadrats, each measuring 20 m × 20 m for trees and 5 m x 5 m for shrubs and climbers, within three land use systems: farm land (FL), grazing land (GL), and protected area (PA). The diameter at breast height (DBH), richness, evenness, and density of woody species were all measured in the vegetation. The Shannon Weiner Diversity Index was used to examine the diversity of vegetation. A total of 52 woody species belonging to 33 genera, and there were 24 families found. in Gola natural vegetation. Fabaceae was represented by the highest number of species comprising 8 (18.18%), 9 (25.00%) and 8 (32%) of the total number of plant species found in PA, GL, and FL. The PA site had significantly highest population density of vegetation, followed by the GL site, while the FL site had the lowest. The total basal area of PA, GL and FL were 43.73, 31.68 and 22.62 m2/ha, respectively. PA site had significantly (P= 0.042) highest Shannon’s diversity index value with mean (3.53) than the others two land use system. This result suggests significance of anthropological disturbance like grazing and farming on woody species diversity and natural forest ecosystem appeared to be adverse dependent on the category and severity of the anthropogenic disturbances.

Conversion of natural forests to farmlands and its associated woody species diversity and carbon stocks in a span of 33 years (1984 to 2016): in the case of southwestern Ethiopia

Background: Gura-Ferda forest is one of the Afromontane rainforests in the southwestern region of Ethiopia. However, since 1984, large parts of this forest have become increasingly disturbed and fragmented due to forest conversion into forest farm interface and farmlands. The study was conducted to assess changes of woody species diversity and carbon stock in association with the conversion of natural forest to forest farm interface and farmlands. Methods: Data were collected from natural forest, forest farm interface and farmland which are historically forest lands before 1984. A total of 90 nested plots (20m×20m for natural forest and forest farm interface; 50m*100m for farmland)) were established for inventory of woody species. Three 1m×1m subplots were established to collect litter and soil samples. A total of 180 soil samples were collected. The total carbon stocks were estimated by summing carbon stock in the biomass and soil (0-60 cm depth). Results: Results showed that Shannon-Wiener diversity (H’) in forest farm interface (H’ = 1.57) is relatively lower than that of natural forest (H’ = 3.33) but higher than farmland (H’ = 1.42). The total carbon stocks of natural forest were approximately 1.21 and 2.54 times higher than that of forest farm interface and farmland. Conclusion: Our study revealed that the changes of Natural Forest to Forest Farm Interface and Farmland have effects on the diversity of woody species and carbon stocks.