1. ARBAMINCH UNIVERSITY
SCHOOL OF GRADUATE
S STUDENT
FACULTY OF NATURAL SCIENCE
DEPARTMENT OF HYDROLOGY AND METEOROLOGY
EARTH SYSTEM MODELING
SUBMITED BY MEKONNEN DABA
MAY 20, 2011
2. DEFORESTATION: ETHIOPIA AND ITS IMPACTS
INTRODUCTION
1. Deforestation and land degradation and their climatic impacts
Deforestation refers to the conversion of forested land into non-forested lands
such as agricultural, cattle pastures, residential areas, lakes and deserts.
Deforestation in Ethiopia is due to locals clearing forests for their personal
needs, such as for fuel, hunting, agriculture, housing development, and at
times for religious reasons.
Deforestation is the process of removing the forest ecosystem by cutting the
trees and changing the shape of the land to suit different uses.
Among developing countries, especially in Africa, Ethiopia is exceptionally rich
in history, as well as cultural and biological diversity.
4. Cont’d…
It is home to one of the earliest ancestors of the human species, around
80 languages are spoken by various ethnic groups, and it is home to two
globally important biodiversity hotspots. However, this rich cultural
and natural heritage is threatened, especially in the form of
deforestation.
Ethiopia has the second largest population in Africa and has been hit
by famine many times due to rain shortages and a depletion of natural
resources. Deforestation may have further lowered the already meager
rainfall. As the population continues to grow, the needs of the people
increase. The country has lost 98% of its forested regions in the last 50
years due deforastation and impact on land degradation.
5.
6. Cont’d…
One of the major challenges facing Ethiopia in striving for
development is environmental degradation, manifested in the
degradation of land and water resources as well as loss of biodiversity.
Land degradation is expressed in terms of soil erosion and loss of soil
fertility. Deforestation/devegetation is one of the major factors
contributing to land degradation by exposing the soil to various agents
of erosion. With high-intensity rainstorms and extensive steep slopes,
Ethiopia is highly susceptible to soil erosion, especially in the
highlands. The organic content of soils is often low due to the
widespread use of dung and crop residues for energy.
7.
8. Cont’d…
Land degradation in turn greatly affects agricultural productivity and
production. In 1990 alone, for instance, reduced soil depth caused by
erosion resulted in a grain production loss of 57,000 (at 3.5 mm soil
loss) to 128,000 tons (at 8 mm soil depth). It has been estimated that
the grain production lost due to land degradation in 1990 would have
been sufficient to feed more than four million people.
The availability of land suitable for agriculture is shrinking, while at
the same time the amount of land required to feed the growing
population is steadily increasing.
With agricultural productivity increases lagging behind population
growth rates, the gap between availability and demand for agricultural
land continues to grow, resulting in severe land-use conflicts between
crop farming, animal grazing, and forestry.
9. Cont’d…
Forestry can play a role in reducing land pressure and land
degradation, but forestry alone cannot solve the problem. Even
if the management of existing forest resources is improved and
new trees and forests are established, this may well prove futile if
high population growth rates continue to increase the need for
crop and grazing land.
Using the land for forestry to improve soil fertility or to
rehabilitate and conserve the environment will be viewed as
secondary to using the land for cropping and grazing to meet
immediate survival needs.
Attempts to alleviate land degradation are therefore critically
dependent on efforts to deal with the three main underlying
causes of land degradation, namely population growth, low
agricultural productivity, and high dependence on fuel wood,
dung, and crop residue as sources of household energy.
10. Cont’d…
Considering the magnitude of the land degradation problem,
conservation programs implemented so far are inadequate.
The policy, institutional, planning, and technical constraints
responsible for the inadequacy of past conservation efforts are
presented, and any future initiatives to overcome the escalating land
degradation problem in Ethiopia should first address these constraints
realistically.
There are no universal formulae or solutions that can work across the
board; rather, solutions should be locality-specific and closely tied to
the socioeconomic setup of the communities.
11. Cont’d…
In this regard, forestry can play a significant role in either preventing
or arresting land degradation by avoiding or reducing soil erosion
through reduced surface runoff and maintenance of organic matter and
soil fertility. It can help not only in addressing off-farm and on-farm
dimensions of soil erosion but also in maintaining the fertility of the
soil, thereby alleviating land degradation and the destruction of
natural resources.
Favorable climatic and ecological conditions, sufficient rainfall,
moderate temperatures, and well developed soils in the Ethiopian
highlands may have been the basis for early development of
agricultural systems and high human population in this agro-climatic
zone.
12. Cont’d…
50% of the remaining highlands are highly susceptible to erosion. FAO
(1984) reported that on two million ha of cultivated land, the soil depth
is so reduced that the land is no longer able to support any vegetative
cover.
The Hararghae highlands in Eastern Ethiopia, Tigrai, Wollo, and
Semen Shoa highlands in the North and the Gamo-Gofa highlands and
the Bila-te River basin, which starts in Eastern slopes of Gurage
highlands and stretches through Eastern Hadiya and Kembatta
highlands, are some of the seriously eroded land surfaces in Ethiopia.
The highland areas in Ethiopia are defined and delineated to represent
the land areas above 1500 m a.s.l. and the lowlands are defined as areas
below 1500 m a.s.l. in altitude. More than 90% of Ethiopia’s population
live in the highlands including about 93% of the cultivated land,
around 75% of the country’s livestock and accounts for over 90% of the
country’s economic activity.
14. Cont’d…
Land degradation is seriously threatening the economic and social
development of the country as a whole.
Due to degradation, increasing number of Ethiopians have become
vulnerable to the effects of drought.
The severity of the devastating droughts and the resulting famines in
1972/73 and 1984/85 can be attributed to an accelerating process of
degradation combined with widespread general poverty of the
population.
Measurements of land degradation usually focuses on the severity of
soil erosion mainly caused by high-intensity rain storms on rugged
geomorphic features, steep slopes, and barren land surfaces highly
susceptible to soil erosion.
15. Deforestation and Climate Change
Global climate change is a widespread and growing concern that has
led to extensive congressional and international discussions and
negotiations. Climate change mitigation strategies have focused on
reducing emissions of greenhouse gases (GHGs), especially carbon
dioxide (CO2). One significant source of CO2 emissions is
deforestation. Reducing deforestation to lower CO2 emissions is seen
as one of the least costly methods of mitigating climate change.
Forests are carbon sinks in their natural state (i.e., they store more
carbon than they release).
17. Cont’d…
Trees absorb CO2 and convert carbon into leaves, stems, and roots,
while releasing oxygen.
Forests account for more than a quarter of the land area of the earth,
and store more than three quarters of the carbon in terrestrial plants
and nearly 40% of soil carbon.
When forests are cleared, some of their carbon is released to the
atmosphere—slowly through decay or quickly through burning. One
estimate shows that land use change, primarily deforestation, releases
about 5.9 Gt CO2 (giga tons or billion metric tons of CO2) annually,
about 17% of all annual anthropogenic GHG emissions.
This contribution to GHG emissions makes efforts to reduce
deforestation significant in international strategies to mitigate climate
change.
19. Linkages between Forests and Climate
Deforestation is the loss of tree cover, usually as a result of forests being
cleared for other land uses such as farming or ranching.
Some limit the definition of deforestation to the permanent
conversion of forests to another habitat. Others add to this definition
by including the conversion of natural forests to artificial forests such
as plantations.
Deforestation activities affect carbon fluxes in the soil, vegetation, and
atmosphere.
The effects of these activities can vary, depending on the type of
activity. For example, logging can lead to carbon storage if trees are
converted to wood products (e.g., lumber) and deforested areas are
restored.
20. Cont’d…
. However, logging can also lead to carbon emissions if the
surrounding trees and vegetation are damaged, and if not all woody
biomass is processed into products. Other activities that alter the
carbon cycle in forests and affect climate.
21. Deforestation in Ethiopia
I. Natural Forest cover
Ethiopia‘s flora and fauna have a large number of species with a
considerable rate of endemism.
Forests and woodlands provide various benefits in the country
including as sources of wood and construction materials, land for
farming and grazing, non wood forest products and services and
various ecological functions some of which have global values.
However, with a growing human population of about 75 million largely
dependent on low-productivity and rain-fed agriculture and over 70
million livestock population competing for land and forest resources,
deforestation and forest degradation are important problems in
Ethiopia.
22. Cont’d…
The forest cover in Ethiopia is estimated at less than 4%
compared, for example, with an average of 20% for sub-Saharan
Africa (Earth Trends, 2007; WBISPP, 2004). The rate of
deforestation is estimated to be as high as 5% per year (EFAP,
1994a; Reusing, 1998; WBISPP, 2004b).
Reduction in forest cover has a number of consequences
including soil erosion and reduced capacity for watershed
protection with possible flooding, reduced capacity for carbon
sequestration, reduced biodiversity and instability of ecosystems
and reduced availability of various wood and non-wood forest
products and services.
23. Cont’d…
Forests in Ethiopia play a big role in protecting erosion, as tree
roots protect against washouts. Trees also help to keep water in
the soil and reduce global warming by uptake of carbon dioxide.
Because there are not enough trees, the Blue Nile is carrying all
the soil and nutrients in the water to the neighboring countries
of Sudan and Egypt.
At the beginning of the twentieth century around 420,000
square kilometers (35% of Ethiopia’s land) was covered by trees
but recent research indicates that forest cover is now less than
14.2% due to population growth.
Despite the growing need for forested lands, lack of education
among locals has led to a continuing decline of forested areas.
24. Cont’d…
Change in Forest Cover: Between 1990 and 2000, Ethiopia lost an
average of 140,900 hectares of forest per year.
The amounts to an average annual deforestation rate of 0.93%. Between
2000 and 2005, the rate of forest change increased by 10.4% to 1.03%
per annum.
In total, between 1990 and 2005, Ethiopia lost 14.0% of its forest cover,
or around 2,114,000 hectares. Measuring the total rate of habitat
conversion (defined as change in forest area plus change in woodland
area minus net plantation expansion) for the 1990-2005 intervals,
Ethiopia lost 3.6% of its forest and woodland habitat.
25. II. Causes of deforestation
The major cause of deforestation in Ethiopia is the rapid population
growth, which leads shifting agriculture, to an increase in the demand
for crop and grazing land, livestock production, wood for fuel drier
areas and construction.
Lack of viable land use policy and corresponding law also aggravated
the rate of deforestation.
New settlements in forests are increasing from time to time and hence
resulted in the conversion of forested land into agricultural and other
land use systems.
At present, the few remaining high forests are threatened by pressure
from investors who are converting the moist evergreen montane forests
into other land use systems such as coffee and tea plantations.
27. Cont’d…
Developing nations are faced with a two-edged sword in the field of
energy.
On the one hand the rising price of oil has reduced the potential for
fossil fuel energy and eroded foreign exchange reserves in oil-
importing countries.
At the same time deforestation may be causing increased prices or
shortages of fuels such as fuel wood and charcoal
29. III. Annual trend of natural
forest cover and deforestation
Ethiopia Forest Information and Data
About 12,296,000 ha or 11.2% of Ethiopia is forested,
according to FAO. Of this 4.2% (511,000 ha) is classified as
primary forest, the most biodiversity and carbon-dense
form of forest.
Ethiopia had 511,000 ha of planted forest. Change in
Forest Cover: Between 1990 and 2010, Ethiopia lost an
average of 140,900 ha or 0.93% per year.
In total, between 1990 and 2010, Ethiopia lost 18.6% of its
forest cover or around 2,818,000 ha.
Ethiopia's forests contain 219 million metric tons of carbon
in living forest biomass.
30. Cont’d…
Biodiversity and Protected Areas: Ethiopia has some 1408 known
species of amphibians, birds, mammals and reptiles according to
figures from the World Conservation Monitoring Centre.
Of these, 7.0% are endemic, meaning they exist in no other country,
and 4.6% are threatened.
Ethiopia is home to at least 6603 species of vascular plants, of which
15.1% are endemic. 4.9% of Ethiopia is protected under IUCN
categories I-V.
31. Ethiopia: Forest Cover, 2010
Total Land Area (1000 square
109631
kilometers)
Total Forest Area (1000 ha) 12296
Percent Forest Cover 11
Primary Forest Cover (1000 ha) 0
Primary Forest, % total forest 0
Other wooded land (1000 ha) 44650
Percent other wooded land 41
32. Ethiopia: Breakdown of forest types, 2010
Primary forest (1000 ha |
0 0
% of forest area)
Other naturally regenerated
forest (1000 ha | % of forest 11785 96
area)
Planted Forest (1000 ha | %
511 4
of forest area)
33. Ethiopia: Trends in Total (Net) Forest Cover, 1990-2010
TOTAL FOREST COVER (1000 ha)
1990 2000 2005 2010
15114 13705 13000 12296
ANNUAL CHANGE RATE (1000 ha)
Negative number represents deforestation
1990-2000 2000-2005 2005-2010
-141 -141 -141
38. Ethiopia: Trends in carbon stock in living
forest biomass 1990-2010
CARBON STOCK IN LIVING FOREST BIOMASS (million metric tons)
1990 2000 2005 2010
ANNUAL CHANGE (1 000 t/yr) 254
289 236 219
0 1990 -4 2000 -4 2005 -3 2010
1222
9000
9001
0050
nnn
...
sss
...
39. Impact of deforestation in Ethiopia
Deforestation is a major concern in Ethiopia as studies suggest loss of
forest contributes to soil erosion, loss of nutrients in the soil, loss of
animal habitats and reduction in biodiversity, averting of water quality,
and climate change.
The vegetation resources and ecology of Ethiopia, including forests,
woodlands and bush lands, conservation of soil, have been studied by
several scholars who have employed different methods and have
studied different localities to come up with conclusions.(deferu,2010).
40. Cont’d…
One of the major impacts of deforestation is through its effect in
reducing the level of agricultural production and productivity, making
the nation unable to feed its people.
This situation has often necessitated increased volume of food
imports, in the form of commercial imports and also as food aid.
In addition, the high level of deforestation has resulted in worsening
the household energy consumption problems in Ethiopia, as fuel wood,
dung and crop residue are the major sources of household energy
consumption.
42. Cont’d…
During the next few decades, global ecological changes are expected to
have major impacts on ecological, social, economic, and political
aspects of human society (Dale, 1997).
The ecological impacts include changes to biodiversity, productivity,
migration, safety, and sustainability.
Climate and land use changes are two major global ecological changes
predicted for the future.
Therefore causes and consequences of human-induced climate change
and land use activities have largely been examined independently
(Turner et al., 1993). However, climate change and land use affect each
other
43. Cont’d…
Land use activity contributes to climate change and soil erosion, and
changes in land cover patterns are one way in which the effects of
climate change is expressed.
Land use is the human modification of natural environment or
wilderness to build fields, pastures, and settlements. The major effect
of land use on land cover has been deforestation of temperate regions
(IPCC, 2007).
More recent significant effects of land use include urban spread out,
soil erosion, soil degradation, salinization, and desertification. Land
use and land management practices have a major impact on natural
resources including water, soil, nutrients, plants, and animals.
44. Cont’d…
According to a report by the United Nation Food and Agriculture
Organization (FAO, 1995), land degradation has been exacerbated
where there has been no effective land use planning, or of its orderly
execution, or the existence of financial or legal incentives that have led
to the wrong land use decisions, or one-sided central planning leading
to overutilization of the land resources - for instance for immediate
production at all costs.
As a consequence, the result has often been misery for large segments
of the local population and destruction of valuable ecosystems. Such
narrow approaches should be replaced by a technique for the planning
and management of land resources that is integrated and holistic and
where land users are central.
45. Cont’d…
This will ensure the long term quality of the land for human use,
the prevention or resolution of social conflicts related to land
use, the conservation of ecosystems of high biodiversity value,
and mitigation of the rate of climate change.
Land use effects on climate change and soil erosion include both
implications of land use change on atmospheric flux of carbon
dioxide (CO2) and its subsequent impact on climate and soil,
and the alteration of climate change impacts through land
management. An effect of climate change on land use refers to
both how land use might be altered by climate change and what
land management strategies would mitigate the negative effects
of climate change.
46. Cont’d…
The direct ecological effects of land use and climate change are
dominated by the land use change effects, at least over a period of a few
decades (Dale, 1997).
Because climate change effects are largely determined by land cover
patterns, land use practices set the stage on which climate alterations
can act.
Determining the effects of climate change on land use involves
resolving direct biophysical effects as well as management responses to
climate impacts. The population density on given land use system links
deforestation with soil erosion and facilitates their effects on climate
change through land use of human activity.
There are two aspects to considering impacts of land use: effects of
land use on climate change and soil erosion; and the effects of human
induced climate change on land use.
47. 4. Mechanism (ways) to stop
deforestation
Controlling deforestation
Farming
New methods are being developed to farm more intensively,
such as high-yield hybridcrops, greenhouse, autonomous
building gardens, and hydroponics.
These methods are often dependent on chemical inputs to
maintain necessary yields. In cyclic agriculture, cattle are grazed
on farm land that is resting and rejuvenating.
Cyclic agriculture actually increases the fertility of the soil.
Intensive farming can also decrease soil nutrients by consuming
at an accelerated rate the trace minerals needed for crop growth.
48. Forest management
Efforts to stop or slow deforestation have been attempted for many
centuries because it has long been known that deforestation can cause
environmental damage sufficient in some cases to cause societies to
collapse.
49. Reforestation
In Ethiopia deforestation is a major problem and many peasants have
switched from fuel wood to dung for cooking and heating purposes,
thereby damaging the agricultural productivity of cropland.
The Ethiopian government has embarked on a two-pronged policy in an
effort to stem deforestation and the degradation of agricultural lands:
(i) tree planting or afforestation; (ii) dissemination of more efficient
stove technologies.
The motivation in here is, therefore, to examine the potential of the
strategy of disseminating improved stoves in the rehabilitation of
agricultural and forests lands.
50. Forest plantations
To meet the worlds demand for wood it has been suggested by forestry
that high-yielding forest plantations are suitable.
It has been calculated that plantations yielding 10 cubic meters per
hectare annually could supply all the timber required for international
trade on 5 percent of the world's existing forestland.
By contrast natural forests produce about 1-2 cubic meters per hectare,
therefore 5 to 10 times more forest land would be required to meet
demand. Forester Chad Oliver has suggested a forest mosaic with high-
yield forest lands interspersed with conservation land.
52. Cont’d…
Carrying out afforestation programme and improved management of
forest resources alone, however successful, will not be able to solve our
problems as far as our need for crop and grazing land continues to grow
due to high population growth rates.
This is because of the fact that using the land for forestry to improve
soil fertility or to rehabilitate and conserve the environment will be
viewed as secondary to using the land for cropping and grazing to meet
immediate needs of survival.
53. Cont’d…
Hence, any attempt by the government, the public and NGOs to
address the problem of deforestation in particular and land
degradation in general critically depends upon our efforts and capacity
to deal with the three major issues of population growth, low
agricultural productivity and high dependence on fuel wood, dung and
crop residue as sources of household energy. Finally, the government
should devise and implement strategies and policies relating to
afforestation only as an integral part of the overall rural development
programme.