Abstract:
Drought is the most complex but least understood of all natural hazards. It is
broadly defined as “sever water shortage”. Low rainfall and fall in agriculture
production has mainly caused drought. A droughts impact constitutes losses of life,
human suffering, damage to economy and environment. In recent years, Geographic
Information System (GIS) and Remote Sensing (RS) have played a key role in
studying different types if hazards either natural or man-made. This study stresses
upon the use of RS and GIS in the field of Drought Risk assessment. In this study an
effort has been made to derive spatial-temporal drought risk areas facing agriculture
as well as meteorological drought by use of temporal images from Landsat ETM
based Normalize Difference Vegetation Index(NDVI) (2003, 2009 and 2015) and
meteorological based Standardized Precipitation Index(SPI).Correlation analysis was
performed between NDVI, SPI, and rainfall anomaly. SPI values were interpolated to
get the spatial pattern of meteorological based drought. NDVI threshold was
identified to get the agriculture drought risk. Similarly rainfall and NDVI were
correlated and a spatial temporal drought risk maps were generated.Study area District
Khushab was divided into three zones including no drought, slight drought and
moderate drought. The results revealed that 41.43% are under no drought, 28.36%
area under slight drought and 30.21% is the area under moderate drought. It was
evident from the study that southern part of District Khushab was a rainfall deficit
area with scarce vegetation and hence was the area with the highest drought
prevalence. The results obtained can be helpful for drought management plans and
will help in revealing true drought situation in the area.
