appropriate planning for it's use and conservation. 
In addition, this limit of 100 kilometers is held to 
be a commercial limit regarding the cutting and 
transport of fuelwood to the major population center 
by private woodcutters. With their level of 
organization these woodcutters can very quickly 
impact the resource and up-to-date information about 
the supply is necessary to design appropriate 
programs to regulate this commercial activity. The 
five circles are centered around the cities of 
Niamey, Dosso, Tahoua, Maradi and Zinder. Note that 
the Maradi zone is truncated due to contact with the 
border with Nigeria. The total area addressed is 
approximately 150,000 square kilometers. 
2.3 Source or base data available for the selected 
zone 
A major element identified during the formulation 
of the approach was the types and amount of source, 
or base, data available for the zone. With 
respect to statistical information concerning 
fuelwood volumes, no supportable or comparable data 
existed. In addition to a lack of statistical data, 
there was also a lack of appropriate base maps for 
the five urban zones. The production of these maps 
was included as a necessary aspect of the general 
approach. Research showed a very limited amount of 
existing ground data but good availability of other 
types of data. Complete coverage of all five zones 
is available in the topographic map series, at a 
scale of 1/200,000, published by the french Institut 
Géographique National (IGN). The five zones are also 
completely covered by IGN acquired stereo aerial 
photography. Some parts of the zones are covered by 
photos taken in 1975, at a scale of 1/60,000, and 
others in 1979, at 1/70,000. Finally, LANDSAT 
satellite, multispectral scanner (MSS) data is also 
available in complete coverage. This imagery was 
ordered and produced in the false-color infrared 
format (bands 4, 5 and 7), and at a scale of 
1/200,000 to permit direct comparison with the IGN 
topographic maps. 
3.0 PROCEDURES USED TO ESTIMATE FUELWOOD VOLUMES 
FOR THE FIVE URBAN ZONES 
Given the objectives of the inventory process, the 
constraints under which the inventory was carried 
out, the mentioned lack of certain types of 
information or base data, and the base data that was 
available, the two phase procedure was defined. The 
first phase produced the base map and the second, the 
estimation of fuelwood volume. The specific 
procedures employed will be presented in the 
following sections 
3.1 Phase I: Production of the base maps for the 
individual urban zones 
The objective of this initial phase is to produce 
base maps of each of the urban zones which can be 
used as a stratification tool to increase the 
efficiency of the sampling procedure. The essential 
element of an appropriate stratification is that it 
must minimize the variabilty in the data sampled 
within a strata type, and maximize the variability 
between strata types. In the context of this 
inventory it is desirable to create stratas that are 
significantly different from the standpoint of 
fuelwood volume. However, given the scales, and 
correspondingly low resolutions, of the LANDSAT 
images and aerial photographs available, it was not 
possible to interpret fuelwood volume categories 
directly. It was, therefore, necessary to identify 
conditions which could be identified given the base 
data available, and which was correlated to 
Figure 1. A map of the Republic of Niger showing the five urban zones for which fuelwood volume was estimated. 
Each zone has a radius of 100 kilometers, giving a surface area of 31,400 square kilometers, and has as it's 
center a major city. Note that the zone around the city of Maradi is truncated due to contact with the border 
with Nigeria. The area of this zone is approximately 21,000 square kilometers. The total area addressed is 
approximately 150,000 square kilometers.