(cest2017_00658) Drought risk assessment using GIS and remote sensing: A case study of District Khushab, Pakistan

摘要

Drought is the most complex but least understood of all natural hazards. It is broadly defined as “sever water shortage”. 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.