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 ad...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.展开更多
This study evaluates the role of shelterbelts on the development and dynamics of vegetation in relation to livelihoods in the study area using geo-information techniques. The study covered the period between 1972 and ...This study evaluates the role of shelterbelts on the development and dynamics of vegetation in relation to livelihoods in the study area using geo-information techniques. The study covered the period between 1972 and 2007. The results show that in 1972 vegetation cover in the study area extended over an area of 6955 hectares (i.e.?shrubs, grasses and trees) which represents 65% of the area;however there was a decrease in 1986 to an area of 5779 hectares (54%). Despite the establishment of shelterbelt in the area in 1987, the trend did not change. This is obvious in the reduction of vegetation cover between 1986 and 2000 to a total area of 3893 hectares (37%). The vegetation cover further decreased to 2791 hectares (26%) in 2005 and 1659 hectares (16%) in 2007 respectively. The study concludes that the establishment of shelterbelts alone cannot guarantee the success of vegetation cover development in the area without a sustainable plan which recognizes the local communities as critical stakeholders. Thus, variables like population growth and GDP have a role to play in vegetation cover depletion. The study recommends that efforts geared towards enlightenment of the local communities on the need for conservation should be encouraged by Government and Non-Governmental Organisations.展开更多
文摘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.
文摘This study evaluates the role of shelterbelts on the development and dynamics of vegetation in relation to livelihoods in the study area using geo-information techniques. The study covered the period between 1972 and 2007. The results show that in 1972 vegetation cover in the study area extended over an area of 6955 hectares (i.e.?shrubs, grasses and trees) which represents 65% of the area;however there was a decrease in 1986 to an area of 5779 hectares (54%). Despite the establishment of shelterbelt in the area in 1987, the trend did not change. This is obvious in the reduction of vegetation cover between 1986 and 2000 to a total area of 3893 hectares (37%). The vegetation cover further decreased to 2791 hectares (26%) in 2005 and 1659 hectares (16%) in 2007 respectively. The study concludes that the establishment of shelterbelts alone cannot guarantee the success of vegetation cover development in the area without a sustainable plan which recognizes the local communities as critical stakeholders. Thus, variables like population growth and GDP have a role to play in vegetation cover depletion. The study recommends that efforts geared towards enlightenment of the local communities on the need for conservation should be encouraged by Government and Non-Governmental Organisations.
