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<td width="396" valign="middle" bgcolor="#829db6"><font size="1" face="Arial, Helvetica, sans-serif"><strong>
<font color="#FFFFFF" size="4"> Sahel Workshop Final
Report </font></strong></font></td>
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<td width="800" height="1493" bgcolor="#829db6"> <blockquote>
<p align="justify"><font face="Arial, Helvetica, sans-serif"><strong><a href="sahel_bkgd.html"><back></a></strong></font></p>
<p align="center"><font color="#FFFFFF" size="4" face="Arial, Helvetica, sans-serif"><strong>Final
Report<br>
UNEP/FAO/UNCCD<br>
Workshop on changes in the Sahel<br>
Nairobi<br>
14-16 October 2003</strong></font></p>
<p align="center"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>SUMMARY</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">For
the last four decades there has been sustained scientific interest
in contemporary environmental change in the Sahel. It suffered
several devastating droughts and famines between the late 1960s
and early 1990s. Speculation about the climatology of these droughts
is unresolved, as is speculation about the effects of land clearance
on rainfall and about land degradation in this zone. However,
recent findings suggest a consistent trend of increasing vegetation
“greenness” in much of the region. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Time
series data from satellite have been analyzed for the African
Sahel to study recent trends in vegetation greenness. A strong
increase in seasonal greenness was observed over large areas of
the Sahel during the period 1982-1999. Preliminary studies indicate
a continuation of the trend through 2003. Analyses of rainfall
data indicate increasing rainfall during the same period. However,
the greening trend cannot be explained solely by rainfall. While
extensive, the greening is not uniform, suggesting that factors
other than rainfall may be contributing to greening of some areas
and not others. In addition, the resolution of the satellite data
set is coarse (8 km). So, the pattern of greening that might help
explain its causes may be partly obscured by the resolution of
the data.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">“Recovery”
is not a helpful term. It means a return to conditions that existed
at some assumed equilibrium point in the past. When an equilibrium
system is disturbed, its tendency is to seek equilibrium. In the
case of the ecology of the Sahel, disturbances might be drought
or, in the case of livestock, it might be pressure from grazing
animals. When that pressure is removed (i.e., the rains return
or the animals move elsewhere), the system returns to equilibrium.
This implies that during the period of disturbance, vegetation
cover is reduced and some species may decline, others increase,
and still others may invade. Recovery, in this sense, would be
a return to initial species composition and cover. However, there
are other models of non-equilibrium that argue that, rather than
a single equilibrium point, there may be multiple equilibrium
points. Thus, in our simple example, the state at which the original
array of species and cover has been reduced and invaders increased
may represent a new equilibrium point because the relationship
among species or nature of the soil has changed because of erosion.
Yet, it may have a “greenness” value that is similar
to the original state because overall plant cover may be the same
although species composition has changed.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Human
livelihood systems might be viewed to operate in a similar manner.
Using a similar equilibrium model, a given household or community
might enjoy some level of income (agricultural production) and
command a set of resources (e.g., livestock; farm implements)
in their livelihood system at some point in the past. When this
livelihood system is disturbed (e.g., drought) there appear to
be two types of trajectories that households might follow. In
the common degradation model, households must draw down their
resources (i.e., sell their livestock and farm implements), seek
employment, or migrate. In the equilibrium model, it is assumed
that when rains return, opportunities for agricultural production
improve and households then may “recover.” However,
because they have a much-diminished productive capacity at this
new equilibrium point, it is extremely difficult for them to move
to a new, higher equilibrium point, even if rains remain good.
</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">An
alternative adaptation model has emerged to counter the degradation
model. Limited ground studies have shown that some farmers and
communities have adapted to the changes during the droughts experienced
in the Sahel and improved management of water and soil fertility
that increase production. As these change increase returns, farmers
invest in more inputs, livestock, and crop diversification. This
suggests that they are moving toward a more positive equilibrium
point than in the degradation trajectory. While promising in that
it shows that success can be achieved with and without outside
intervention, these success stories serve a broader purpose by
suggesting model strategies that might be pursued. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Altogether,
these findings suggest continued caution in interpreting the greening
phenomenon, particularly with respect to how it might influence
policy and any actions that might be taken in the near future.
While it may be true that climatic conditions have improved, it
is not possible to predict how long this may continue. It is certain,
though, that drought will return and that policy should be flexible
enough to accommodate that certainty and the non-equilibrium conditions
that accompany it.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">As
suggested above, there are other positive developments that come
from long term environmental and agricultural studies in the region
that can provide a new narrative to guide efforts to stabilize
and improve agriculture and natural resource management in the
region.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Several
studies on long-term environmental and agricultural change in
the Sahel (in Niger, Nigeria, Burkina Faso and Senegal). These
studies have found evidence of significant transitions from degradational
land use trajectories to more sustainable and productive production
systems. These include increases in cereal yields, higher densities
of trees, improved soil fertility management, locally higher groundwater
tables, reductions in rural poverty, and decreased outmigration.
These changes coincided with growth in rural populations and introduction
of structural adjustment policies. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">While
limited in their extent, it is likely that more such ‘success
stories’ will be found in the Sahel, which collectively
challenge the narrative of Sahelian degradation which has informed
policy for the last few decades. These success stories could provide
the basis for a new narrative that is based on the ability of
farmers and livestock producers to manage their livelihoods under
non-equilibrium conditions of variable rainfall, finite land resources
and low bioproductivity. The biophysical and management changes
that have been identified suggest that they are less the helpless
victims of environmental change than agents who try to make the
best use of productive and investment opportunities. </font></p>
<p align="justify"> </p>
<p align="center"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>RECOMMENDATIONS</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>1.
Confirmation and exploration of greening </strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Initiate
further interrogation of the data used to detect the greening
trend. This would include: </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">•
updating the time series, <br>
• quality assessment and correction, <br>
• further analysis of patterns at varying spatial and temporal
scales,<br>
• derivation of biophysical information</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>2.
Assessment of recovery</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Initiate
validation campaign comparable to those associated with other
remote sensing observations (e.g., TRMM) to establish systematically
(a) what greenness means on the ground, (b) how changes relate
to human well-being and environment.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">•
Identification of areas of change, <br>
• Select sample study sites from larger area,<br>
• Characterize samples,<br>
• Establish degrees of change,<br>
• Establish causative factors for observed changes. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>3.
Assessment of apparent anomalies</strong><br>
<br>
While there is evidence that the conditions for farmers and livestock
producers have declined in terms of production and soil fertility,
other ground studies have documented success stories of farmers
and livestock producers who have adapted successfully to conditions
in the Sahel. These should serve as lessons that could guide future
policy and intervention strategies that might lead to a more positive
perspective on options for renewing agriculture in the Sahel.
This would be achieved through a studied that was focused on:
</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">•
The policy lessons drawn from the existing studies should be applied
to other areas and scaled up to macro-policy level. <br>
• More policy-relevant studies should be undertaken on ‘success
stories’ of agricultural and natural resource management
in order to draw lessons from a wider range of environments, and
to identify constraints to upscaling.<br>
• These studies could be linked to a review of land rehabilitation
activities across the Sahel (approaches, technologies, impact,
upscaling potential).</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Ultimately,
this should lead to policies which:</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">•
Through appropriate policy instruments, incentives should be provided
for innovation and investment in natural resource management (for
example, ensuring security in land and tree tenure, information
diffusion).<br>
• Provide the widest possible range of technical and livelihood
options for rural families.<br>
• Promote the use of institutional channels (existing or
adapted) for locally based management of natural resources, especially
common pool resources.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>4.
Data continuity and exploitation</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Data
will continue to be a critical issue, in terms of availability
and access (i.e., price), but is essential for monitoring and
assessment. To continue and enhance the flow of data:</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">•
Encourage national and regional climate data sharing with partners<br>
• Invest in data mining of historical and systematic gathering
of socio-economic data to provide multi-scale picture of interactions
between climate and changes<br>
• Strengthen climate observation network</font></p>
<p align="justify"></p>
<p align="center"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><br>
<br>
<font size="4"><strong>Final Report<br>
UNEP/FAO/UNCCD<br>
Workshop on changes in the Sahel<br>
Nairobi<br>
14-16 October 2003</strong></font></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><br>
<strong>1.0 Background</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">The
Sahel region of Africa is a dynamic ecosystem that responds to
climatic variability and human exploitation of biospheric resources.
Over the long-term, changes in rainfall may have resulted in changes
in land use patterns. While there has been a tendency to refer
to the desertification of the Sahel, results from analysis of
different types of satellite and ground data have not resulted
in consensus on the direction of changes.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Since
the early 1980s satellite mapping of the global land biosphere
has generated long time-series measurement of vegetation that
can be used as a proxy for understating the dynamics of variability
of the Sahel. A number of studies using these and other data have
shown the close coupling between rainfall and primary production
in the Sahel. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Therefore,
United Nations Environment Programme (UNEP), the United Nations
Food and Agriculture Organization (FAO) and the Convention to
Combat Desertification (CCD) jointly organised a Changes in the
Sahel workshop, from 14 to 16 October 2003 in Nairobi, Kenya,
to bring together scientists (Attachment 1) who have conducted
significant studies in this region to synthesize results over
the last 20 years. </font></p>
<p align="justify"> </p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>2.0
Objectives</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">The
workshop is intended to produce a statement of the current state
of scientific knowledge of changes in the Sahel.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Specifically,
participants will:</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">•
Present results of their recent work addressing the current state
of processes in the Sahel;</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">•
Produce conclusions drawn from these results;</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">•
Based on these conclusions, provide recommendations of future
actions to the sponsoring organizations; </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">•
Prepare and present a summary of the workshop findings at the
conclusion of the workshop.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><br>
<strong><br>
3.0 Approach</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">As
reflected in the Workshop Agenda (Attachment 2), individual papers
were presented by the participants, followed by group discussions
of the presentations. From these presentations and ensuing discussions
conclusions were drawn and agreed upon by the group. Actions to
address these conclusions were then agreed upon and are presented
in the recommendations section of this report. Workshop results
were presented at the conclusion of the workshop.</font></p>
<p align="justify"> </p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>4.0
Results and Discussion</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>4.1
Evolving contexts of the desertification debate </strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">A
great many debates have grown up around the notion of desertification
as a process of degradation that affects the arid, semiarid and
subhumid zones of the globe. A fundamental and continuing debate
has been over whether desertification actually exists and, if
so, how it might be defined, measured and assessed. Rather than
simply review the evolution of these debates we examine the contexts
in which they take place and how those contexts have contributed
to the evolution of our understanding of the intertwined processes
that contribute to desertification. The fact that these “contexts”
have changed over time, and that some of these contexts are often
ignored have helped sustain debate. We consider four “contexts”
that frame much of the debate and consider what impact each has
had: (1) changes in our understanding of climate variability;
(2) changes in our understanding of vegetation responses to perturbation;
(3) changes in our understanding of social processes, including
household responses to economic perturbation; and (4) changes
in our understanding of desertification as a political process
or artifact. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>4.2
Policy implications of the Sahelian recovery </strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">The
Sahelian greening is one phase in a continuous sequence of wet
and dry periods. Here, we examine policies in the light of these
changes. We consider policies involved both in other greenings
and in the Sahel itself. Others include Sinai, southern Russia,
Arizona and the Loess Plateau in northern China. In Sinai, the
policies that brought about greening include exclusion, emigration
and nature conservation. In Russia, the policy that had impact
was the collapse of the Soviet collective farm system. In Arizona,
it came after the Taylor Grazing Act of 1934 which allowed the
US Forest Service to manage grazing. On the Loess Plateau, it
has been the result of irrigation, tree-planting, the extension
of responsibility of land users and perhaps aerial seeding and
fencing. Most of these policies are inapplicable to the Sahel,
with the possible exception of some of the Chinese measures. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">In
the Sahel, some policies in Burkina Faso, and elsewhere did enable
soil and water conservation projects, but the success of these
projects is more due to the harnessing of local skills. More generally,
policy has had little to do with the greening (as with the earlier
browning), even though the Sahel has been a seething cauldron
of policy debate for three decades. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Sahelian
environmental policies face two main challenges: fast and occasionally
extreme fluctuations in rainfall; and changes in the scientific
dialectic. There should be less emphasis on the negative policy
of controlling land degradation, and more on positive policies
that encourage adaptation and allow for rapid deployment to make
use of good years and insurance policies against bad ones.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>4.3
Greening of the Sahel </strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">For
the last four decades there has been sustained scientific interest
in contemporary environmental change in the Sahel. It suffered
several devastating droughts and famines between the late 1960s
and early 1990s. Speculation about the climatology of these droughts
is unresolved, as is speculation about the effects of land clearance
on rainfall and about land degradation in this zone. However,
recent findings suggest a consistent trend of increasing vegetation
greenness in much of the region. It is not possible to explain
the vegetation trend by rainfall only. There are other possible
causes of this trend such as land use change, migration and armed
conflicts. There are also policy implications of a positive trend
in biophysical conditions. One conclusion is that more site-specific
information on the interaction of biophysical dynamics (climate,
soils, vegetation) and farming systems (farming practices and
risk management strategies) is needed in order to better understand
and ultimately support the development challenge in the Sahel.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>4.4
The impact of soil and water conservation on agriculture and environment
on the northern part of the Central Plateau of Burkina Faso between
1980 and 2001 </strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">In
the beginning of the 1980s the situation on the northern part
of the densely populated Central Plateau was dramatic: drought
years succeeded each other, food shortages at household level
were endemic and the environment had become degraded. The commonly
held view is that the process of environmental degradation continued
in the second half of the 1980s as well as in the 1990s. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">A
study was recently undertaken by a multidisciplinary team of national
researchers, who looked at long-term changes in agriculture and
environment in this region. Most of their research findings show
positive trends. Cereal yields have increased by about 50% since
1984-88; in two of the three provinces studied the cultivated
area remained stable during the last 15 years; tree density and
species diversity are higher on fields treated with soil and water
conservation than on untreated fields; livestock numbers have
increased and livestock management is evolving from extensive
to semi-intensive and a survey in 59 villages shows that, according
to the villagers, local groundwater levels have improved substantially
since the start of soil and water conservation. Based on criteria
used by villagers, which are mainly related to levels of household
food security, rural poverty seems to have decreased significantly
(up to 50%) in villages with soil and water conservation. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Much
has been achieved, but much more remains to be done. It is urgent
to improve soil fertility on cultivated land and to fight against
land degradation on uncultivated land, which continues unabated.
</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>4.5
Twenty-three years of Sahelian vegetation dynamics from NOAA-AVHRR
</strong> </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Satellite
measurements of the global biosphere in the form of the normalized
difference vegetation index (NDVI) have generated a 23 year time
series appropriate for the studies seasonal to interannual vegetation
dynamics of the Sahel region. The close coupling between Sahelian
rainfall and the green-up of vegetation has made it possible to
utilize this vegetation index data set as a proxy for the land
surface response to climate variability. Examination of the this
time series principally reveals two major periods: (a) 1982-1993
marked by below average vegetation and persistence of drought
with a signature large scale drought during the 1983-1985 period;
and (2) 1994-2003, marked by a trend towards “greener”
conditions with region-wide above normal vegetation conditions
in 1994. Spatial patterns enable us to conclude that is not a
footprint of desertification, rather they indicated the variability
of green vegetation biomass over the region in response to interannual
variations in rainfall. Systematic studies of changes on the landscape
at local scales using high spatial resolution satellite data sets
such as those from LANDSAT, SPOT and MODIS will allow for an improved
documentation of degradation of Sahelian land resources that could
lead to desertification.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>4.6
Do farmers’ long-term responses to economic and environmental
change support an hypothesis of Sahelian desertification? </strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">The
term ‘desertification’ can be considered in terms
relevant to small farmers’ practices and strategies, and
the expectations generated by an hypothesis of Sahelian desertification
reviewed. Long-term data sets (1960-2000) collected at the district
level in three Sahelian countries (Diourbel Region, Senegal; Maradi
Department, Niger; and the Kano region, northern Nigeria), together
with village-level field enquiries, conducted in 1999-2000, these
data were used to construct profiles of change in a range of relevant
variables. These profiles were then synthesized to obtain lessons
for policy, which was one of the principal drivers of farmers’
responses in each of the districts. A simple theory of ‘desertification’
is found inadequate for understanding the complexity, diversity
and flexibility of farmers’ responses to change. While questions
of sustainability arise in relation some variables (e.g., fertility
management under cultivation), some sub-hypotheses of desertification
are found to be in need of re-thinking in relation to others (e.g.,
tree management). Natural resource management as a whole cannot
be understood except in terms of livelihood strategies based on
diverse portfolios of on- and off-farm income sources, and interaction
between Sahelian and sub-humid or humid agro-ecological zones
and cities.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>4.7
UNCCD perspectives on the changes in the Sahel </strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">The
plight of the Sahel was brought into the international arena by
the reports of the debilitating drought of the early seventies
and its attendant massive loss of life and property. The international
community made attempts to address the issues of drought and desertification
by the establishment by UNCOD in 1977, but the resulting Plan
of Action fell short of expectation.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">The
UNCED process and the resultant Chapter 12 of Agenda 21 led to
further consideration, but there was still a need for a legally
binding instrument. The birth of the UNCCD, a Convention to address
the fight against drought and desertification the world over was
the vehicle. This was a call for paradigm shift, a different way
of dealing with the twin problems of drought and desertification.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">The
“United Nations Convention to Combat Desertification in
Those Countries Experiencing Drought and/or Desertification, Particularly
in Africa,” with its entry into force in December of 1996,
has 190 signatories to date. The thrust of the UNCCD is for concerted
local level action, but with international level support and partnership.
Its objective is: </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">“to
combat desertification and mitigate the effects of drought…..through
effective action at all levels, supported by international co-operation
and partnership arrangements, in the framework of an integrated
approach which is consistent with Agenda 21, with a view to contributing
to the achievement of sustainable development in affected areas.”</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">The
UNCCD recognizes that achieving this objective will involve long-term
integrated strategies that focus simultaneously, on improved productivity
of the land and the rehabilitation, conservation, and sustainable
management of land and water resources, leading to improved living
conditions, in particular at the community level.<br>
The Sahel is a major entry point in understanding and eventually
addressing the complex problems of recurrent droughts and the
ever-present desertification and land degradation. The particular
attention given to Africa by the UNCCD includes the Sahel, as
testimony to the need to take concrete action in that region.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Various
interacting forces come into the picture, in influencing not only
natural processes, but also possible remedial measures. Traditional
knowledge and coping strategies of the affected peoples, early
warning systems, provide some of the tools required to address
the challenges that imposed by the often adverse climatic factors,
ecological factors, anthropogenic factors encountered in the region.
These are all important components to be taken into consideration
when looking at the “Changes in the Sahel”. The combined
action of these at local level, national level as well as appropriate
international interventions in one way or another hold the key.
</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>4.8
Monitoring vegetation growth and mapping changes in landscape:
Senegal case study </strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">A
lack of early warning system in the early 1970s prevented governments
and even researchers from having a good appreciation of the droughts
that occurred, in semi-arid zones, particularly in 1972.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Since
this period, developing tools to monitor vegetation growth and
to estimate available forage for cattle has been a major concern
for decision makers. The Centre de Suivi Ecologique (CSE) has
developed various products to address these needs. Decadal NDVI
information and annual biomass maps using NOAA/AVHRR and SPOT/Vegetation
data are some of the products successfully elaborated and regularly
published since 1987. More recently, some other indicators like
VCI and SPI have been successfully applied to drought monitoring
in Senegal. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">The
process has allowed CSE to set up a NOAA database of well-calibrated
images. These data have been used to look at the tendency of vegetation
growth at a national level. At a more localized level, several
studies based on satellite images and aerial photos from the 1960’s
until 2000 have been conducted to map changes in land use and
land cover. CSE is still continuing to work on these kinds of
studies with FAO, UNEP and GEF in the framework of the Land Degradation
Assessment (LADA) project. It is aiming to identify hot and bright
spots and to document their causes using mapping and census data.
<br>
Early warning systems are now used in some Sahelian countries
on a more operational basis and can be expanded to all Sahelian
countries. Detection of changes in the Sahel landscape can be
done at large and localized scales (access to high resolution
data still needs to be improved). Generalization on very large
areas should be done carefully. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>4.9
Long-term precipitation variability in the Sahel </strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">The
Sahel has undergone tremendous fluctuations of rainfall throughout
historical times. Extreme and prolonged droughts are an inherent
feature of the environment. The fluctuations have been particularly
extreme during the last half of the 20th century. The mean rainfall
for 30-year periods, the traditional time period for a climatic
“normal”, decreased 25% to 40% in the Sahel between
1931 – 1960 and 1968 – 1997. the contrast is even
greater when the wettest and driest decades, the 1950s and 1980s,
are compared. During those decades, the entire continent was affected.
That clearly demonstrates that the main causes of rainfall variability
are to be found in the large-scale general atmospheric circulation.
These in turn are at least partially driven by sea-surface temperature
variability, however El Nino/La Nina does not play a large role.<br>
Most of the change takes place in August. Wet/dry conditions in
the Sahel tend to be associated with a northward/southward displacement
of the rainbelt over West Africa. In some cases, however, the
reduction in rainfall is associated with an overall weakening
of the tropical rainbelt. There is little relationship between
the amount of rainfall during the season and length of the season
or its onset date. These facts have strong implications for both
adaptive strategies and predictability.<br>
The persistent dry conditions prevailed from the late 1960s through
the mid-1990s. TRMM satellite data that was validated with a dense
gauge network showed that the region became markedly wetter in
1998. Relatively good rainfall continued through the next year.
As a whole rainfall of the last 6 years has been better than average,
but the “wet” conditions of the 1950s were not matched.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>4.10
Regional variability, local relative degradation: How to manage
scale</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Desertification
has to be clearly distinguished from desert encroachment, which
is linked with the romantic idea of the desert encroaching irreversibly
upon green areas. Different thresholds of land and soils degradation
have been used to assess the loss of natural resources, and differ
considerably according to the idea of irreversibility as the ultimate
stage of degradation (which is desertification on a 25 years basis).
We have no evidence to say that the drought period has ended,
nor can we say that there is a global trend towards a drier climate
since the last century. So that the greening Sahel, following
the yellowing Sahel of the 70’s, is just an expression of
climate variability: the desert did not encroach upon the arid
Sub-Saharan regions.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Whether
land use changes (towards fewer range pastures, more fields and
fallow fields, less fallow period, etc) are responsible or not
for soil and land degradation cannot be assessed just through
a global survey at regional scale: degradation (loss of soil material,
decreasing in production) depends upon the way populations are
using their space and resources (human density, technology, etc.).</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Examples
from north Saharan countries, where animal pressure increased
during the drought period due to national actions taken to mitigate
the effect of the drought, show that we must differentiate between
land degradation and/or desertification (which correspond to the
loss of production capability) and resources degradation, which
expresses a decreasing value for human use.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Combining
bio-physical and socio-economical assessment and monitoring, functional
models at a local scale and structural monitoring at the national
or regional scale, could help understanding the trends in desertification.
These are the objectives of the ROSELT/OSS program.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>4.11
Environmental and land cover changes in the Sahel region: Lessons
learned, challenges and priority actions</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">During
the last three decades, the Sahel region has been confronted with
various forms of environmental and ecological degradation due
to climate change and anthropogenic pressures. These changes have
been described as the most important that the region has ever
faced. Recent studies and analysis show spatial and temporal patterns
changes and variability in landscape features, tree-crop patterns,
and forest cover, with severe degradation of soils and fragile
ecosystems.<br>
However, their impacts could have been mitigated or even reversed
through constructive policies and concerted and collaborative
efforts with a focus on priority areas where the conservation
and rehabilitation of fragile lands could be the most cost effective.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Since
2002, the LADA team (a partnership among FAO, UNEP and GEF) is
carrying out studies focused on the assessment of the status and
trends of these changes, including their impacts on livelihoods
and identification of hotspots. LADA aims to generate up-to-date
information related to ecological and environmental changes, including
economical, social and technical aspects, traditional knowledge
and practices on land management which have occurred in drylands
during these decades.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">The
principle objective of the LADA project is to develop methods
and tools to assess and quantify the nature, extent, severity
and impacts of land degradation on ecosystems, watersheds and
river basins, carbon storage and biological diversity in drylands
at a range of spatial and temporal scales. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">The
project will also build national, regional and global assessment
capacities to enable the design and planning of interventions
to mitigate land degradation and establish sustainable land use
and management practices. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>4.12
The utilization of geoinformation technology for agroenvironmental
applications in Egypt </strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Remote
sensing can provide valuable and timely information about natural
resources and environmental conditions which are important for
sustainable development. However, in developing countries, the
utilization of such advanced technologies differs from one country
to another. Egypt, as a developing country, has experience in
the utilization of Earth observation satellites and aircraft remote
sensing data in soil mapping as well as assessment of land degradation.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Agriculture
in Egypt depends mainly on irrigation, which has been practiced
since pre- historic times by Egyptians, and is still used today
in similar ways. The main source of irrigation water in Egypt
is the Nile River. Despite implementing a number of projects to
regulate the Nile, much of its water is still not used properly
with an efficiency of less than 50% and salinization as a consequence.
By adopting irrigation practices that seek to match irrigation
amount with different crop requirements will save a great deal
of water while conserving soils and rendering them saline. <br>
</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>5.0
Conclusions</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">After
presentation were made, the group identified seven issues that
are associated with the changes that have been observed in the
Sahel. They were framed as questions.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>1.
IS THE SAHEL “GREENING”? </strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">This
question and its policy implications are the primary purpose of
the meeting.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>Conclusion:
</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">For
the last four decades there has been sustained scientific interest
in contemporary environmental change in the Sahel. It suffered
several devastating droughts and famines between the late 1960s
and early 1990s. Speculation about the climatology of these droughts
is unresolved, as is speculation about the effects of land clearance
on rainfall and about land degradation in this zone. However,
recent findings suggest a consistent trend of increasing vegetation
greenness in much of the region. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">AVHRR
NDVI data have been analyzed for the African Sahel to study recent
trends in vegetation greenness. A strong increase in seasonal
NDVI was observed over large areas in the Sahel during the period
1982-1999. Preliminary studies indicate a continuation of the
trend through 2003. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Although
strong shifts in satellite overpass times have led to shifting
solar zenith angles (SZA) over the time period, only minimal influence
of SZA’s on the Pathfinder NDVI has been found in the data.
Meticulous quality assessment of other parameters related to the
data, strongly supports the conclusion that the observed trend
is a real change on the land surface. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Analyses
of rainfall data indicate increasing rainfall during the same
period. However, the greening trend cannot be explained solely
by rainfall. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>Implications:
</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">“Getting
it wrong” will have adverse impacts on the development future
of local and national populations in the Sahel, as well as the
institutions designed to deal with problems of dryland management
everywhere.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>2.
IS THIS RECOVERY?</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">“Recovery”
is not a helpful term. It means a return to conditions that existed
at some assumed equilibrium point in the past. When an equilibrium
system is disturbed, its tendency is to seek equilibrium. In the
case of the ecology of the Sahel, disturbances might be drought
or, in the case of livestock, it might be pressure from grazing
animals. When that pressure is removed (i.e., the rains return
or the animals move elsewhere), the system returns to equilibrium.
This implies that during the period of disturbance, vegetation
cover is reduced and some species may decline, others increase,
and still others may invade. Recovery, in this sense, would be
a return to initial species composition and cover. However, there
are other models of non-equilibrium that argue that, rather than
a single equilibrium point, there may be multiple equilibrium
points. Thus, in our simple example, the state at which the original
array of species and cover has been reduced and invaders increased
may represent a new equilibrium point because the relationship
among species or nature of the soil has changed because of erosion.
Yet, it may have a “greenness” value that is similar
to the original state because overall plant cover may be the same
although species composition has changed.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Human
livelihood systems might be viewed to operate in a similar manner.
Using a similar equilibrium model, a given household or community
might enjoy some level of income (agricultural production) and
command a set of resources (e.g., livestock; farm implements)
in their livelihood system at some equilibrium point in the past.
When this livelihood system is disturbed (e.g., drought) the income
stream is disrupted. There appear to be two types of trajectories
that households might follow. In the common degradation model,
confronted with reduced income, households must draw down their
resources (i.e., sell their livestock and farm implements), seek
employment, or migrate. In the equilibrium model, it is assumed
that when rains return, opportunities for agricultural production
improve and households then may “recover.” However,
because their labor force is reduced, and productive assets are
gone, they have reached a new equilibrium point. Because they
have a much-diminished productive capacity, it is extremely difficult
for them to move to a new, higher equilibrium point, even if rains
remain good. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">An
alternative adaptation model has emerged to counter the degradation
model. Limited ground studies have shown that some farmers and
communities have adapted to the changes experienced in the Sahel
over the past 30 years (see 4.4. and 4.6). Adaptations begin with
improved management of water and soil fertility. As these change
increase returns, farmers invest in more inputs, livestock, and
crop diversification that are all intended improve economic their
position. This suggests that they are moving towared a much different
– and positive – equilibrium point than in the degradation
trajectory. While promising in that it shows that success can
be be achieved with and without outside intervention, these success
stories provide model of strategies that might be pursued. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>Conclusion:
</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">From
an agricultural, ecological, and socioeconomic perspective, it
is not only risky but very probably wrong to assume that increased
greenness signals “recovery.” More importantly, given
the range of potential outcomes that might result for any community
from a general improvement of conditions in the Sahel, the concept
of recovery is does not seem to be particularly useful. “Change”
is a less loaded and more useful concept.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>Implications:
</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">If
it is assumed that increased greenness signals recovery, policies
that are intended to benefit affected populations might be scaled
back or eliminated. However, rather than “recovered,”
conditions on the ground may be quite different and, in fact,
less favorable than they were “before the emergency.”
Moreover, given the range of outcomes of the past 20 years, policies
based on an equilibrium or “recovery” model may do
damage to one or several groups. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>3.
HAS THIS RECOVERY OCCURRED EVERYWHERE?</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Adding
to the difficulty of determining what the greening of the Sahel
might mean is its pattern and scale. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>Conclusion:</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">While
extensive, the greening is not uniform, suggesting that factors
other than rainfall may be contributing to greening of some areas
and not others. In addition, the resolution of the satellite data
set is coarse (8 km). So, the pattern of greening that might help
explain its causes may be partly obscured by the resolution of
the data.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>Implications:</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Sorting
out the patterns of green and nongreen areas is essential for
making sense of the greening phenomenon.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>4.
WHAT OTHER UNEXPECTED CHANGES HAVE OCCURRED?</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Several
studies on long-term environmental and agricultural change in
the Sahel (in Niger, Nigeria, Burkina Faso and Senegal) have found
evidence of significant transitions from degradational land use
trajectories to more sustainable and productive production systems.
These include increases in cereal yields, higher densities of
trees, improved soil fertility management, locally higher groundwater
tables, reductions in rural poverty, and decreased out-migration.
These changes coincided with growth in rural populations and introduction
of structural adjustment policies.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>Conclusion:
</strong> </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">It
is likely that more such ‘success stories’ will be
found in the Sahel, which collectively challenge the narrative
of Sahelian degradation which has informed policy for the last
few decades.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>Implications:</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Known
and currently unknown success stories offer a wide range of potential
lessons that could be widely applied. In essence, they represent
a wide array of successful experiments that are as yet unknown
but with great potential value.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><br>
<strong>5. HOW DO THESE CHANGES REDEFINE THE CHALLENGES TO POLICY?</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">The
changes observed in the Sahel over the past 30 years show it to
be a region of extreme variability. Part of the variability is
climatic, but as seen above, it is also a region in which farmers
are capable of responding creatively to that variability. Policy
must be adept at responding directly to the variations in climate
(both positive and negative) in ways that release the creativity
of farmers and livestock growers to respond to them.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>Conclusion:
</strong> </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">In
some places, as in the central Plateau of Burkina Faso, central
government policies have enabled greening through soil and water
conservation (although the results generally exceeded expectation),
but most of the post 1984 greening was independent of policy or
intervention. This is partly because many policies have arisen
from an unfortunate narrative about degradation, for which the
empirical evidence is inconclusive. Further, they have not addressed
the most important influences on crop production, or the construction
of fertility (as opposed to the inherent fertility) of soils.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>Implications:
</strong> </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Until
now, policy had been informed by a narrative of degradation in
the Sahel. Policy was largely ineffective, but farmers found ways
to improve their conditions in managing, among other things, soil
fertility. If policy can be informed by a narrative that arises
from the creativity of farmers and livestock producers, they may
be better positioned to deal with the inevitable return of drought.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>6.
HOW DO THESE CHANGES REDEFINE THE CHALLENGES FOR LAND USERS? </strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Farmers
and livestock producers will still have to manage their livelihoods
under conditions of variable rainfall, finite land resources and
low bioproductivity. However, the biophysical and management changes
that have been identified suggest that they are less the helpless
victims of environmental change than agents who try to make the
best use of productive and investment opportunities. Externally
funded interventions and macro-policies have played a part in
this evolution, together with local initiatives on a sustained
and significant scale.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>Conclusion:
</strong> </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Farmers
have a capacity to experiment and to innovate, especially in areas
with high pressure on the available resources. This capacity should
be supported and enhanced, for example by means of participatory
research and extension, and strengthened local institutions.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>Implications:</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Continued
innovation in land use practices and investment in natural resources
is a condition for sustainable livelihoods in the longer term.
</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><br>
<strong>7. ARE THE DATA WE GATHER AND ANALYZE APPROPRIATE FOR
DETERMINING AND UNDERSTANDING THIS TREND?</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Evidence
of the greening pattern over the region has been drawn from analysis
of a limited set of biophysical (greenness) and climatic data
(rainfall). However, part of the greening phenomenon cannot be
attributed to rainfall alone. Thus, other data may be required
to understand greening and what it means. Second, rainfall data
is problematic for the region in terms of availability. This may
be partially overcome by relying on satellite estimates of precipitation.
However, in addition to its intrinsic value for studying climate
and its use in driving climate models, rainfall data are used
to validate satellite estimates. </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><br>
<strong>Conclusion:</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Efforts
must be made to continue to make rainfall data available. An over-
reliance unvalidated satellite data is problematic. Other types
of data (i.e., socioeconomic) should be explored to help explain
changes that are observed within the Sahel.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>Implications:</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">To
have confidence in observed trends in greenness requires a convergence
of evidence. It is risky to rely on a single source of information.
Data from rainfall gauges is sometimes problematic, but so too
is unvalidated satellite data. Similarly, while these two measures
might suggest trends in biophysical conditions, those may be unrelated
to conditions of human well-being.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong><br>
6.0 Recommendations</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>1.
Confirmation and exploration of greening </strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">The
data used to detect the greening trend should be interrogated
further. Four main aspects can be distinguished: </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">•
Continuation of the time series: The present time series generally
available covers the period from July 1982 through 2000. The year
2000, however, is of inferior quality due to the gradual shift
of SZA. It is important to make the continuation of the time series
also generally available.<br>
• Further quality assessment and correction: The time series
available has not gone through state-of-the art data processing.
By reprocessing the entire database using the latest processing
schemes we can anticipate further removal of noise and atmospheric
contamination. <br>
• Further data analysis: There are a number of intriguing
patterns that deserves further studies. The analyses so far have
concentrated to the time integrated NDVI. Other characteristics
may reveal patterns that can contribute to the disentangling of
the biophysical meaning of the trend, such as i) the seasonal
timing and amplitude of NDVI, ii) the onset and end of seasons
and iii) the rate of increase and decrease of the seasons.<br>
• Derivation of biophysical information: In order to derive
biophysical information, the NDVI time series should be used as
a driving force of a biophysical model. This will result in a
much more meaningful, and for land management more useful, information,
expressed as Gross/Net Primary Production (kg/m2)</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>2.
Assessment of change </strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Initiate
validation campaign comparable to those associated with other
remote sensing observations (e.g., TRMM) to establish systematically
(a) what greenness means on the ground, (b) how changes relate
to human well-being and environment. This major effort would include:</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">•
Identification of areas of change. All positive changes would
be inventoried to establish population of targets from which to
draw sample study areas. They would be identified from the (a)
satellite record, and (b) areas of documented change on the ground
(irrespective of corroborative satellite data). These would be
compared with rainfall data to determine the degree to which changes
could be attributed to climate.<br>
• Select sample study sites from pool. Samples of change
with controls (no change) would be drawn from the population for
systematic study. These would form a base from which the impacts
of change could be established now, but also monitored at a future
time to develop a more profound understanding of change (both
positive and negative).<br>
• Characterize samples. First, samples would be studied
using remote sensing (satellite data and aerial photography) and
field sampling to characterize them biophysically (soil, vegetation,
land use, land cover, infrastructure). In addition, historical
remote sensing data would be used to establish conditions (to
the degree possible) at some reference point in the past. Second,
household surveys would be conducted within subsampled areas within
each sample to characterize (a) their livelihood systems and (b)
socioeconomic conditions and how they had changed between now
and some point in the past. These, too, would serve as long-term
reference points for longitudinal studies of human response to
change. <br>
• Establish degrees of change. Changes (positive and negative)
will be manifest in a number of different ways that will vary
from place to place. Likely biophysical measures would include
changes in vegetation and land cover, infrastructure development,
conservation interventions, and soil erosion. Likely socioeconomic
measures might include changes in population, agricultural production,
wealth, and measures of well-being (e.g., child weight-to-height
ratios, morbidity and mortality, malnutrition), and general food
security.<br>
• Establish causative factors for observed change. The data
collected will be analyzed to understand the reasons change occurred
and the degree to which different factors influenced outcomes.
Improved rainfall may be an important factor, but others such
as changes in soil and water management practices are expected
to be important.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>3.
Assessment of apparent anomalies</strong><br>
<br>
While there is evidence that the conditions for farmers and livestock
producers have declined in terms of production and soil fertility,
other ground studies have documented success stories of farmers
and livestock producers who have adapted successfully to changing
conditions in the Sahel. These should serve as lessons that could
guide future policy and intervention strategies that might lead
to a more positive perspective on options for renewing agriculture
in the Sahel.. This would be achieved through a study that was
focused on: </font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">•
The policy lessons drawn from the existing studies should be applied
to other areas and scaled up to macro-policy level. <br>
• More policy-relevant studies should be undertaken on ‘success
stories’ of agricultural and natural resource management
in order to draw lessons from a wider range of environments, and
to identify constraints to upscaling.<br>
• These studies could be linked to a review of land rehabilitation
activities across the Sahel (approaches, technologies, impact,
upscaling potential).</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Ultimately,
this should lead to policies which:</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">•
Through appropriate policy instruments, incentives should be provided
for innovation and investment in natural resource management (for
example, ensuring security in land and tree tenure, information
diffusion).<br>
• Provide the widest possible range of technical and livelihood
options for rural families.<br>
• Promote the use of institutional channels (existing or
adapted) for locally based management of natural resources, especially
common pool resources.</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><strong>4.
Data continuity and exploitation</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Data
will continue to be a critical issue, in terms of availability
and access (i.e., price), but is essential for monitoring and
assessment. To continue and enhance the flow of data:</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">•
Encourage national and regional climate data sharing with partners<br>
• Invest in data mining of historical and systematic gathering
of socio-economic data to provide multi-scale picture of interactions
between climate and changes<br>
• Strengthen climate observation network</font></p>
<p align="justify"> <font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><br>
</font></p>
<p align="justify"> <font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><br>
NOTE: Relevant results from the workshop will be refereed and
printed in a special issue of the Journal of Arid Environments.
<br>
</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><br>
<strong>ATTACHMENT 1: LIST OF PARTICIPANTS</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">1.
Dr. Assaf Anyamba<br>
NASA/Goddard Space Flight Center<br>
E-mail: [email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">2.
Dr. Charles Hutchinson<br>
College of Agriculture and Life Sciences<br>
University of Arizona<br>
E-mail: [email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">3.
Dr. Sharon E. Nicholson<br>
Dept. of Meteorology<br>
Florida State University<br>
E-mail: [email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">4.
Dr. Lennart Olsson<br>
Centre for Environmental Studies<br>
University of Lund<br>
[email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">5.
Dr. Andrew Warren<br>
University College London<br>
E-mail: [email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">6.
Dr. Assize Toure<br>
Centre de Suivi Ecologique (CSE)<br>
Senegal<br>
Email: [email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">7.
Dr. Wilbur K. Ottichilo<br>
Regional Centre for Mapping of Resources for Development (RCMRD)<br>
Nairobi, Kenya<br>
E-mail [email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">8.
Mr. Antonio di Gregorio<br>
Africover / FAO<br>
Nairobi, Kenya<br>
E-mail: [email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">9.
Mr. Jean-Marc d'Herbes<br>
ROSELT/OSS<br>
Montpellier CEDEX 05, France<br>
Email: [email protected]<br>
</font><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><br>
10. Mr. Chris Reij<br>
International Cooperation center<br>
Vrije Universiteit<br>
E-mail: [email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">11.
Dr. Michael Mortimore<br>
Drylands Research<br>
United Kingdom<br>
Email: [email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">12.
Dr. Mahmoud H. Ahmed<br>
National Authority for Remote Sensing and Space Science,<br>
Cairo, Egypt<br>
E-mail: [email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">13.
Mr. Jim Weber<br>
International Center for Remote Sensing of Environment (ICRSE)<br>
E-Mail: [email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">14.
Dr. Abdoulaye Kignaman-Soro<br>
ACMAD<br>
Niamey, Niger<br>
e-mail: [email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">15.
Mr. Mounkaila Goumandakoye<br>
Drylands Development Center /UNDP<br>
Nairobi, Kenya<br>
Email: [email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">16.
Dr. Syaka Sadio<br>
Forest Resources Division, FAO<br>
Rome, Italy<br>
E-mail: [email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">17.
Mr. Ndegwa Ndiang'ui<br>
UNCCD<br>
Bonn, Germany<br>
E-mail: [email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">18.
Mr. Timo Maukonen,<br>
DEWA / UNEP,<br>
Nairobi, Kenya<br>
E-mail: [email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">19.
Dr. Ashbindu Singh, <br>
DEWA/RONA/UNEP<br>
Washington, D.C. USA<br>
E-mail: [email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">20.
Dr. Steve Lonergan,<br>
DEWA / UNEP<br>
[email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">21.
Mr. Ivar Baste<br>
DEWA / UNEP<br>
[email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">22.
Dr. Anna Tengberg,<br>
DGEF / UNEP<br>
[email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">23.
Dr. Mohamed Sessay<br>
DGEF / UNEP<br>
[email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">24.
Mr. Jinhua Zhang<br>
DEWA / UNEP<br>
[email protected]</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">
Observers:</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">
Mr. Michael Norton-Griffiths<br>
Nairobi, Kenya<br>
Email: "M.Norton-Griffiths" <[email protected]></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">
Mr. Dave MacDevette<br>
Cape Town , South Africa<br>
Email: [email protected]<br>
</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><br>
<strong>ATTACHMENT 2: WORKSHOP AGENDA</strong></font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">UNEP
/ FAO / UNCCD Workshop on Changes in the Sahel</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Nairobi</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">14-16
October 2003</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">Tuesday,
14 October 2003</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">0900
Welcome and opening statement S. Lonergan, UNEP, Kenya <br>
0930 Introductions and Administrative Announcements T. Maukonen,
UNEP, Kenya<br>
1000 Review and Adoption of Agenda J. Weber, ICRSE, USA<br>
1030 Coffee<br>
1100 UNEP perspectives T. Maukonen, UNEP, Kenya <br>
1130 FAO Perspectives S. Sadio, FAO, Italy<br>
1200 UNCCD perspectives N. Ndiangui, UNCCD, Germany<br>
1230 Lunch<br>
1400 Evolving Contexts of the desertification debate C. Hutchinson,
U of Arizona, USA<br>
1430 Sahelian Rainfall S. Nicholson, Florida State U, USA<br>
1500 23 years of Sahelian vegetation dynamics A. Anyamba, NASA/GSFC,
USA <br>
1530 Greening of the Sahel L. Olsson, U of Lund, Sweden <br>
1600 Coffee<br>
1630 Discussion Participants<br>
1730 Adjourn</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><br>
Wednesday, 15 October 2003</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">0900
Regional Variability J. d’Herbes, ROSELT, France<br>
0930 Egypt’s perspective M.H. Ahmed, NARSSS, Egypt<br>
1000 A new land cover classification system W. Ottichilo, A. DiGregorio,
Kenya<br>
1030 Coffee <br>
1100 Discussion Participants <br>
1200 Lunch <br>
1400 Changes and vegetation growth in the Sahel A. Toure, CSE,
Senegal<br>
1430 Impacts of change in the Sahel A. Kignaman-Soro, ACMAD, Niger
<br>
1500 Impact of Soil/Water conservation on Agriculture C. Reij,
ICC, Netherlands<br>
1530 Coffee <br>
1600 Discussion Participants<br>
1700 Adjourn</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif"><br>
Thursday, 16 October 2003</font></p>
<p align="justify"><font color="#FFFFFF" face="Arial, Helvetica, sans-serif">0900
Policy Implications of the Sahelian Recovery A. Warren, UCL, UK
<br>
0930 Farmers responses to economics and environment M. Mortimore,
Drylands Research, UK <br>
1000 Coffee <br>
1030 Discussion Participants<br>
1200 Lunch<br>
1400 Drafting of preliminary report Participants<br>
1700 Presentation of Preliminary Report Participants<br>
1800 Adjourn</font></p>
<p></p>
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Sahel Workshop Contact:</strong> <br>
Stefanie Herrmann, ICRSE Workshop Secretariat<br>
<a href="mailto:[email protected]">[email protected]</a> -- (520) 626-8064 Voice -- (520) 621-3816 FAX</font><br>
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