Studies around the world
have shown that vegetation cover is undergoing a dramatic change at various
scales. Vegetation is a very important component of the ecosystem, its
destruction by whatever means will have an adverse effect on the functional
role it plays in the environment. Hence, it is necessary to monitor, conserve
and utilize these vital resources sustainably. This study monitors vegetation dynamics
in Mubi region with the view to understand the status of vegetation cover and
suggest possible conservation measures. The study used regression differencing
method of change detection to identify the status and dynamics of vegetation
cover in the region. Landsat satellite images were used to create Normalized
Difference Vegetation Index (NDVI) using IDRISI software. The NDVI images were
subjected to diverse analysis ranging from image registration to image
regression, differencing and thresholding. The results from these analysis
shows that vegetation cover in the region has witnessed unprecedented
degradation. In the period between 1987 and 1999 (12 years) the area that
experienced depletion in vegetation cover in the region was 10,501.42 hectares
while the period between 1999 and 2015 (16 years) witnessed further depletion
to 32,701.77 hectares. The areas that experienced restoration in vegetation
cover in the region from the period between 1999 and 2015 (24,098.94 hectares)
have lower areal extent compared with the period between 1987 and 1999
(44,045.80 hectares). This phenomenon is not unconnected with population growth
as the region has witnessed explosive growth in the recent past. This growth in
population has resulted in higher demand for food to feed the growing
population thereby leading to expansion of farmland. High demands for fuelwood
by the increasing populace have also contributed to increase in deforestation.
Removal of vegetation cover at such a scale will eventually have negative consequences
on the ecosystem as its functional roles in the environment are jeopardized.
Hence, there is a need to preserve and conserve vegetal resources through
sustainable use.
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