.Moently however, population pressure and land hung
er in the settled areas have created a kind of
influx and spontaneous land occupation in the fron
tiers- The availability of extensive stretches of
hitherto uncultivated land hag induced wasteful and
degradational land use practices which have already
created social and ecological inbalances within the
fragile environment of the frontiers. The social
conflicts have partly cane frcrn inbalancesin land
appropriation between the in-ccmers and the host
peasantry. The latter, at the on set, viewed the
migrant and the absentee land holder as a weleaned
partner in socio-econonic development of the front
iers, and was very flexible with very easy terms of
land acquisition. The former on the other hand, had
to repatriate the returns from his frontier enter
prise to his origin to meet the initial financial
liabilities incurred for the enterprise. The host
people's antagonistic reaction to this has partly
been articulated with incidiarism and bloody clashes.
The deliberate crop burning has contributed to the
serious soil and vegetation losses primarily initia
ted by the deep ploughing and complete uprooting of
the cover threes-a type of land management that has
accompanied the high yielding variety system (HYV)
and its associated agro-chemical application.
Anticipatory Environmental Policies (OECD, 1979) have
to be initiated in order to protect not only the
physical environment frem further deterioration but
also to take into consideration thè local people's
present and future land needs. To create the basic
harmony recjuired for sustainable kind of exploitation
of the frapile renewable resources, the present
status quo has to be mapped and quantitative informa
tion of it provided.
Happily, the holistic and synopic qualities of the
existing and prospective satellite imageries offer
enormous elasticity that could be stretched to meet
the imagination of both the mapper and the map users.
The area selected for the present study was the Mid
Ialite Volta Basin, where the Kulpawn , the Nasia and
Nabogo streams enter the principal stream (fig I'd
It lies in the NorthernRegion of Ghana,
Figure 1. Northern Ghana showing the study area -
The Mid - White Volta Basin
THE STUDY AREA
The area is typical of the harsh environment of the
so-called 'Middle Belt of ktest African", The typical
characteristics include erratic rainfall and mediocre
upland soils which have been regarded as strona limi
tations to successful agriculture; endemicity of
both animal and human diseases like trypaunosemiasis
onchoerciasis,, bilhazia, which have serious debilita
ting effect on the resident population- Historical
as well as cultural factors have also contributed to
the relatively very low population and the general
absence of economic infrastructure (Pullan, 1962,
JMoraan and Ruah, 1969; Mason, 1969; Gleave and White,
1969; Church, 1974).
In the study area scientific investiaations into
potentials of the soils (Obeng,'1975, Adu, 1963)
are seme of the environmental appraisals which have
supplied information about the aaricultural possibi
lities and problems of the region. Recently,
scientific investiaations have been conducted into
the onchocerciasis disease. A follow-uo of long
term systematic control programme which was launched
in 1974-5 in the Volta Basin (OCP 1973, 1984) has
resulted in the effective countrol of transmission
of the oncho disease. The region has conseauently
heen opened up for re-occupation. The Kulpawn
Sissili, Nasia and Nabogo sub-basins, which before
the control programme were hyper-endemic (OCP, 1973)
have,due to the disease control operations attracted
large scale capital intensive aariculture into the
alluvial plains and associated vallevs.
As part of the oriainal OCP plan to rehabilitate
the resident population, the FAO and UNSO (1985) are
plannina to carrv out small scale intearated ago-
forestrv and aquacultural projects in the area.
The situation renuires a status auo maopina that
describes the distribution pattern of occupied areas,
water resources, woodlands, places of range poten
tials, population density regions, etc. The present
study has used the details available within the limits
of the spatial resolution of US landsat 2 imaaery
and available collateral information to provide the
back ground data recruired for purposes including
that of a closer viewing of the area and its land-
based socio-economic evolution.
ACQUISITION AND APPRAISAL OF THE SATELLITE IMAGERY
A review was made of the available landsat scenes
coverina the northern savannahs of Ghana. From 1973
to date only 1975 was found suitable for the study.
That imagery was fully cloud free and it presented
maximum ground view of the end of rain and iust-about
the harvest time agricultural landscape. The cover
vegetation was not yet completely dry. The contrast
between cultivated fields and the native seaetation
was adeauate in terms of colour, tone and sharpness
of the boundaries of the agricultural -Fields.
Three multisnectral bands (MSS) were selected for
compositing:
the green band, which is 4, the red, band 5 and the
near infra-red band 7. The green band individually
expressed the cultural features such as settlement
and the principal roads quite clearlv. Veaetation
appeared liaht and the water bodies also could be
distinguished. The red band showed the healthy
veaetation in dark tones, and the clear, sediment-
free water bodies appeared rather dark. The near
infrared band showed healthy treed veaetation of the
valleys and the stream banks verv briahtlv thereby
renderinaauite well the contrast between the oreen
gallery forest alona the stream banks and neighbour
hood herbaceous veaetation.
The colour cormoositing was prepared by the Earth
Satellite Corporation of Washinoton. The final
product that was interpreted, was a bromj.de print at
an enlaraed scale of 250,000. Althouah the dominant
colour reaistration of the ground features was false,
in that, the real oreen healthy veaetation was falsely
in briaht red, sane features appeared in near natural
colour, for example,the stream water of the rivers
and lakes were in bright blue to deep dark blue; but
the swamos appeared in greenish blue and blueish
green; paved and the metalled surfaces of larae
settlements were blueish. The principal roads
however appeared, yiainlv yellowish white- or reddish
in places where there were avenue tress-