Measuring Landcover Indicies Of Adamawa State Using Remote Sensing And Geographic Information System (Gis) Techniques

Areas covered by marshlands, highlands and plains were needed in each local government area (LGA) as the bases for allocating funds to the LGAs. In recognition of the fact that ground survey techniques are very labor intensive, consumes a lot of time and generally inconveniencing, a GIS technique was adopted. Satellite images of the state were sub divided along the LGA boundaries. Highlands were located visually and digitized into vector polygons, and then by using the polygon tool of the GIS, areas covered by the polygons were determined. The image classification routine was used to isolate marshlands. By going to the ‘Raster Tools…’ menu and specifying the ‘Display/Edit Raster Attributes’ tool, the areas covered by the marshlands were also determined. Areas covered by plains on the other hand were determined indirectly. The area covered by highlands (already computed) was subtracted from the total area of the LGA by using manual qualitative deduction. Since highlands and plains are mutually exclusive, the result of the subtraction is the area covered by plains. It was observed that LGAs with the highest percentage of marshlands are those which R.Benue pass through. It was also observed that marshlands were more plentiful on plains than on the highlands