Monitoring Vegetation Index Dynamics in Semi-Arid Rangelands Using Rainfall, Ground Survey and MODIS Data
Michael Elias Mgalula1, Uwe Richter1, Oliver Hensel1, Christian Hülsebusch2, Brigitte Kaufmann2, Oliver Wasonga2
1University of Kassel, Agricultural Engineering, Germany
Vegetation in the rangelands are greatly altered by human activities such as grazing pressure, deforestation, encroachment of land for cultivation and natural factors such as spatial and temporal variability in rainfall. Interaction of man-made and natural factors predominantly affects vegetation structure and composition in the ecosystem. Among the major concern that faces Eastern Africa rangelands is the growing of land degradation attributed to the increase of cultivation activities. This is a serious concern because rangelands are getting more fragile and vulnerable to environmental changes, thus threatening the pastoralists' livelihood. It is, therefore, imperative to understand the extent and magnitude of changes in vegetation composition over time. This is central for improving landscape conservation. The present research was aimed to examine the extent of vegetation composition changes for Borana plain, in southern Ethiopia. The study assessed the temporal phenological changes of vegetation index (VI) in the croplands and that of natural vegetative land. Rainfall and ground survey data supplemented with MODIS NDVI satellite images with 250m spatial resolution of 16 days composite of January through December 2002 and 2012 were used to analyse vegetation index employing pixel based approach.
Keywords: Crop cultivation, crop phenology, remote sensing, vegetation changes
Contact Address: Michael Elias Mgalula, University of Kassel, Agricultural Engineering, Nordbahnhofstr.1a, D-37213 Witzenhausen, Germany, e-mail: mgalulamikeyahoo.com