Assessment of Exclosure Impact on Carbon Stock and Woody Species Diversity in Tullu Korma, Ejere District, Oromia, Ethiopia: Implication For Climate Change Mitigation

Author(s)

Abstract
Globally, the concentration of atmospheric CO2 is increasing in alarming rate due to anthropogenic activities. The destruction of natural vegetation from different land uses is contributing to the increase of CO2 in the atmosphere and this is resulting in to the current global warming. Rehabilitation strategies on waste lands and degraded forest areas can contribute to both sink and increase in pool of C as well as increasing of the diversity of both wildlife and plant species diversity. Such conservation goals are achieved by setting strategies like area exclosures, by means of protecting the area from interventions of animal and human beings. So, the current study was aimed at assessments of the role of area enclosures for conservation of biodiversity and its contribution for climate change mitigation. Two land uses were purposively selected and a total of 40 plots were set on transect lines for assessment of woody species diversity and carbon stock in the selected land uses. Within each main plot five 4m*4m and 1m*1m subplots were set to collect data for woody species diversity and soil samples respectively. Litter samples were also collected from a 1m*1m sub plots. A total of 120 soil samples were collected from both land uses. A total of 110 woody species, belonging to 54 families were recorded. Of all woody species 110 and 12 species was recorded in the EXs and adjacent farmland respectively. Abundance, species richness, Shannon diversity index, Simpson diversity index, basal area and stem density were significantly higher in the Exclosures than adjacent farmlands. The average woody species density and basal area of Exclosure was 5315(2830) ha-1 & 6(3) for farmland. The Shannon and Simpson diversity indices per plot was 3.19 (±0.37) & 2.25(±0.32) in enclosures and 0.93(±0.09) &0.86(±0.12) in the adjacent farmlands respectively. Mytanus obscure, Carrisa spinarum and Olea europeae were abundant woody species in the exclosure while Rhus vulgaris, Podocarpus falcatus and Carissa spinarum were in the adjacent farmland. The mean total carbon stock (biomass plus soil, 0-60cm ) was significantly higher in Exclosures (81.17 ± 45.21 tCha-1) than adjacent farmland (62.50 ± 43.37 tCha-1). The total above ground biomass carbon stocks were significantly correlated with the species diversity. Finally, this study revealed that Enclosures on degraded highlands contributed to improve woody species diversity and total carbon stock of biomass and soil.

Keywords
Climate change mitigation, Enclosures, Soil carbon, Biomass

Cite this paper
Mulugeta Negeri, Dejene Adugna, Asaye Ayele, Biyansa Hirpo, Tamiru Kuru, Assessment of Exclosure Impact on Carbon Stock and Woody Species Diversity in Tullu Korma, Ejere District, Oromia, Ethiopia: Implication For Climate Change Mitigation , SCIREA Journal of Forestry. Volume 3, Issue 1, February 2022 | PP. 21-56. 10.54647/forestry22025

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