Efiong-Fuller, Emmanuel O.
1. INTRODUCTION
There is the general tendency of countless persons to associate the name "Geoinformation" with sophisticated automated
methods of geodata acquisition, data capture, data analysis, and indeed the entire processes of geoinformation manage-
ment. Geoinformation technology has changed so rapidly that it is difficult for developing countries to keep the pace; yet
they need geoinformation for sustainable development planning. Automated high technology researches in Geoinformation
are desirable and commendable, no doubt, but to achieve "geoinformation for all" educational programmes should be
designed in such a way as to offer training in both the use of sophisticated automated systems as well as low level
technologies (of the developing countries). This is the unique feature of the training programmes at the International
Institute for Aerospace Surveys and Earth Science (ITC), the Netherlands.
In Nigeria, financial constraints and lack of equipment have constituted major obstacles to meaningful studies and re-
searches in Aerial Photo-interpretation, Remote Sensing and indeed geoinformation application in general. Many of the
existing instruments are either obsolete or have since fallen into disrepair, without being replaced. The availability of
' imageries (or more appropriately the non-availability) further compounds the problem.
The present study sought to "make the best of a bad situation" and face up to these constraints through skillful improvization
and use of available facilities. The method thereby developed was then used to contribute to the study of accelerated
erosion that has ravaged this part of the world for the past three decades. It is interesting to note that accurate enough
result was achieved even with the rudimentary facilities.
2. THESTUDY AREA x
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The study area is the portion of the "Uyo Ravine" to the north east of the ||" #
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former University of Cross River State (now University of Uyo), afflictedby |“ # c.
gapping erosional gullies, otherwise known as ravines. The ravines deviate 4 UNIVERSITY
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sharply from the general landscape of Uyo urban and pose immense envi-
ronmental problems (Fig. 1).
Uyo itself is situated roughly on latitude 5903'N and longitude 7955'E, and is
believed to have been first settled as a Military Camp in 1903 ( Ituen, 1988, 2).
Uyo became Provincial Headquarters in 1959; Divisional Headquarters in
1970, and Local Government Headquarters in 1976. In 1987 it was made a
State Capital, on the creation of Akwa Ibom State by the Federal Government
of Nigeria. Figure 1. Location of Study Area
The area is generally less than 60m above mean sea level with the slope of the land surface seldom exceeding 5° - 109, except
in and around the ravines. Geologically the area is underlain by Coastal Plains Sands of late Tertiary Period. This
geological formation consists of unconsolidated to semi-consolidated coarse to medium grained sands with gravels, and
local concentrations of clay.
Uyo has a typical tropical type of Climate with heavy rainfall, high temperatures, and high relative humidity almost all year
round. There are two main seasons, namely: the Rainy or Wet Season from April to October, and the Dry or Hot Season
from November to March. The heavy rainfall constitutes the dominant geomorphic agent responsible for the accelerated
erosion in the area. Uyo is supposed to have tropical rainforest vegetation by virtue of its location; however most of the
land is under cultivation or construction, thus removing the original forest cover.
3. EQUIPMENT ANDMATERIALS
Very simple equipment and materials were involved in this study, and some have even been improvized. These include the
mirror stereoscope, photogrammetric needle, lens magnifier and plastic ruler, aerial photographs and transparent overlay.
390 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B7. Amsterdam 2000.