Nigeria/Miller and Williams 
Approach and Results: Due to the presence of heavy cloud cover in the lower two-thirds of 
the 7 November 1972 Landsat image, the standard black and white and color composite 
prints of the cloud-free, upper portion of the image were overexposed and of little value. 
However, after the digital data for the study area were extracted and nominally rectified us- 
ing a simple affine transformation, a contrast stretch algorithm was applied to each MSS band 
and the resultant sub-images were markedly easier to interpret (Fig. 2.1). The individuai 
forest reserves could be delineated, as well as inconsistencies in the forest cover conditions 
within each reserve. 
The areas of three specific forest reserves were selected from within the 7,000 square kilom- 
eter sub-image: the Oni (approximately 100 sq. km), the Ikeji (approximately 60 sq. km), 
and the Ogbesse (approximately 80 sq. km). Supervised classification maps of these subareas 
were produced using a simple parallelopiped algorithm and the GE Image 100 system at 
NASA/GSFC. Five general land cover classes were mapped consisting of areas of permanent 
agriculture, virgin forest, villages, and two types of cutover brushlands (Figs. 2.2 and 2.3). 
The image employed in this digital classification was one of the very early Landsat-1 frames 
collected when the MSS instrument was being ‘‘shaken down” and thus significant detector 
stripping occurs in the image and the resulting classification maps. While unfortunate, this 
presence of stripping does not deter from the conclusion that significant forest exploitation 
was occurring and could be mapped in two of the three forests examined. Significant en- 
croachment had been made by permanent agriculture into the Ogbesse Forest Reserve (Fig. 
2.2). At the time of the image collection about one-fourth of the western edge of this 
reserve had been cutover and replaced by permanent agriculture. Examination of a geologic 
map of the area indicates that the general area classified into this agricultural class coincides 
with the area of a geologic unit. This unit undoubtedly has yielded a favorable soil type and 
is therefore being followed into the forest reserve regardless of the politically drawn bound- 
ary. The classification map of the Oni and Ikeji forests shows that the general area of their 
setting is not under permanent agriculture, but consists of low value brushland. The south- 
eastern corner of the Oni Forest Reserve is showing significant forest clearing and 
replacement by this brushland type. Direct field inspection of this area confirmed that clear- 
cutting of the reserve was taking place by fully mechanized crews with logging trucks, etc. 
At the present time the limited opportunities for the collection of Landsat imagery of this 
area has substantially restricted the image resources available for this application. The instal- 
lation of a Landsat ground station in Zaire will markedly increase the opportunity for yearly 
image coverage of all the forest reserves of Nigeria. Thus, a practical program for continual 
monitoring of the harvesting of the remaining forest reserves appears to be feasible. 
Further Information 
References 
Miller, L. D., 1975. Final consulting letter report to Mr. Tom Dow, UN/FAO Project 
Manager, High Plains Forest Inventory Project. P.M.B. 5011. Ibadan, Nigeria. 5 p. 
Expe