Hamere Yohannes - Academia.edu (original) (raw)

Papers by Hamere Yohannes

This paper reviews various articles and documents on relationship between climate change and agri... more This paper reviews various articles and documents on relationship between climate change and agriculture. The two-way relationship of climate change and agriculture is of great significance in particular to developing countries due to their large dependence on agricultural practice for livelihoods and their lack of infrastructure for adaptation when compared to developed countries. Agricultural activities are affected by climate change affects due to their direct dependence on climatic factors. In high latitude areas with low temperature, increased temperature due to climate change could allow for longer growing season. Agriculture affects climate through emissions of greenhouse gases (GHGs) such as carbon dioxide, methane and nitrous oxide. These emissions come directly from use of fossil fuels, tillage practices, fertilized agricultural soils and livestock manure in large proportion. Conversely, agriculture could be a solution for climate change by the widespread adoption of mitigation and adaptation actions. This happens with the help of best management practices such as organic farming, agroforestry practice and manure management etc.

Global forests are extremely diverse and provide a variety of ecosystem services incl... more Global forests are extremely diverse and provide a variety of ecosystem services including
carbon sequestration. Large trees are the most effective organisms to stock atmospheric
carbon. Ethiopia has substantial forest resource cover. But there is still limitation of scientific
studies that magnify the role of forests for climate change mitigation. This study focus on the
estimation of selected tree species carbon stock and their variation across different diameter at
breast height, tree height and stem density in Gedo forest. The data collected from 200m
2
sample plots by using systematically stratified sampling method. The main finding of this study
was dominant trees in the forest contribute large amount of total carbon density stock by
storing 74.59% of total carbon. The amount of carbon stocked in selected trees significantly
varies within different diameter and height classes. Trees which have large height and diameter
but smaller in number store large amount of aboveground and belowground biomass carbon
with maximum 589.24ton ha
-1
carbon at higher diameter class. These findings demonstrate that
tree biomass carbon determined by tree stand structure (density, diameter and height).

Forests provide important ecological and environmental benefits. They serve as natural sinker of ... more Forests provide important ecological and environmental benefits. They serve as natural sinker of atmospheric CO
2
to mitigate climate change. In Ethiopia although, there is significant forest resource, the studies oncarbon stock potential and
factors that affect this potential have not been well studied. This study was done with the aim of estimating carbon stock
potential and related factors that affect carbon sequestration in Gedo forest. Data was collected from10m x 20m plot along
transect in systematically stratified forest part. The forest had total mean carbon stock of 523.64 ± 29 ton ha
-1
with
aboveground biomass (281 ± 23.34 t C ha
-1
)and belowground biomass 56.1 ± 4.66 t C ha
-1
), litter biomass (0.41 ± 0.008 t C ha
-1
), deadwood biomass (2.37 ± 1.33 t C ha
-1
) and soil organic carbon (183.69 ± 6.17 t C ha
-1
). Spatial distribution of the carbon
stock varied along environmental gradient. Altitude has inverse relation with aboveground biomass, belowground biomass,
deadwood carbon and total carbon density. Altitude also has significant effect on all carbon pool except litter biomass and soil
organic carbon. More aboveground biomass, belowground biomass and total carbon were found in the middle altitude and
lower carbon was found in the upper altitude. Soil organic carbon and litter biomass carbon decreases with altitude. Deadwood
biomass carbon pool was found only in lower altitude. Based on overall result it is concluded carbon sequestration in a forest
ecosystem is determined by altitudinal gradient.

Forests are known to play an important role in regulating the global climate. Ethiop... more Forests are known to play an important role in regulating the global climate. Ethiopia has a substantial forest
resource; however, these forests are facing a rapid rate of deforestation and degradation. This in turn adversely
affects forest carbon stock under studied in Ethiopia. This study explores the variation of carbon stock due to a
forest disturbance gradient in Gedo forest. Data were collected from 200 m
2
plot along transect in a systematically
stratified forest part. Spatial distribution of the carbon stock varied within forest disturbance gradient. More
aboveground biomass (356.11 ± 37.83 ton/ha), belowground biomass (71.22 ± 7.56 ton/ha) and total carbon (615.16
± 47.58 ton/ha) were found in the least disturbed stand and the lower total carbon (410.32 ± 52.22 ton/ha) was found
in the highly disturbed stand. Dead wood biomass carbon pool was found in least and semi-disturbed stand. Forest
disturbance had a significant effect on aboveground biomass, belowground biomass carbon, total carbon density
and dead wood biomass carbon. Forest disturbance had an inverse moderate significant correlation with the first
three pools and an inverse weak correlation with the later pool. Carbon sequestration in a forest ecosystem was
determined by level of human-induced disturbances.