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the vulnerability of the local partners. Some mà pping projects awarded four to five years ago are
still uncompleted because the foreign exchange to pay the foreign partners before securing the
release of the compilations is not readily available. Also as a result of the economic lull most of
mapping companies that mu sh-roomed during the oil boom are now dusting their equipment
due to no fault of theirs. However, such a situation cou Id have been averted if resources were
harnessed together. .
Initially, one of the untidy practices in contrac
award of photography, control survey and the photogrammetric compilation to different compa
nies. This arrangement did not work out very well because of the problem of ground control
which had to be planned before photography, bearing in mind the type of aerotriangulation
adjustment program available. This situation is fast changing and few mapping constracts are now
given on ‘turn key basis.
t mapping in Nigeria is the separation and
5.3 AERIAL PHOTOGRAPHY
Procurement of aerial photography had hitherto been predormi nantly in the hands of foreign
companies who either worked independently or in close association witn indigenous survey firms.
With the current economic gloom in the country and the attendant scarcity of foreign
exchange, most of these companies demobilized en-ma ss, leaving the industry virtually stranded
for the past three years or more, As a result, many mapping projects have been strangulated. To
arrest the situation a few Nigerian Aerial Photography firm have been set up. It is hoped that
these young firms will be given every encouragement and protection by the government in order
to avoid a repeat of our present experience.
One of the major problems associated with aerial photography acquisition in Nigeria is the
short flying period limited to about three months in the year. The perpetual low lying clouds
cover over the southern part of the country and the harmattan haze from the Sahara which
covers about two-thirds of the country from middle of October to early March make it very diffi-
cult and almost impossible to take clear aeria: photographs. Even during the flying season, only
a few days have clear sky for good aerial photography, this is especially so in the middle belt of
the country and southern part. Thus medium and small scale photography acquisition has always
constitutted a serious bottleneck in the country’s photogrammetric mapping programmes 7
5.4 REMOTE SENSING
Remote sensing in Nigeria is still at interpretation level. Thus the application area is limited to
isolated studies in geology, agronomy, urban studies, soil studies and thematic mapping. Even
though the Landsat and Spot imageries cover the whole of the country no digital image process-
ing equipment for fast and efficient processing and analysis of remotely sensed data for app lica-
tion in urban environmental studies, land use pattern, water resources, oceanography and
metrology.
6.0 FUTURE OUTLOOK
Application of photogrammetry in the ma pping industry in Nigeria within the last three deca-
des has made it possible for the production of the basic topographical map series, which has
covered about 90 percent of the area of this cou ntry. Medium scale mapping at 1:25,000 scale is
currently being executed and has already covered areas around some State capitals. The aerial
photography acquisition at about 60 percent of the country has been completed at 1/25,000.
Large scale maps at 1:2,000 and 1: 1,000 of some state capitals are also available.
