Dergiler / International Journal of Environment and Geoinformatics / 2019 / Cilt: 6 - Sayı: 2
Monitoring Drought and Its Impact on Agriculture Using Drought Indices and Geoinformatics Technology in Patan District, Gujarat
- Sayfa
- 153–162
- DOI
- —
Abstract
Remote sensing (RS) and Geographic Information System (GIS) has played a major role in the study of different types of drought i.e.agricultural or hydrological drought. The present study on agricultural Drought assessment was carried out in the Patan District ofNorth Gujarat, India. This study focuses on the assessment of climate change and its impact on Agriculture using Remote Sensing(RS) and GIS technology. The Landsat-7 TM and Landsat-8 OLI data of February-2002 and February-2018 covering Patan Districtwas analysed for Land use/Land Cover mapping and monitoring changes in agricultural area over the period of 16-years. TheSpectral vegetation index namely Normalized Difference Vegetation Index (NDVI) was computed using Landsat-7 TM and Landsat-8 OLI digital data for assessment of changes in agricultural vegetation during the drought and normal monsoon periods.Meteorological data like Minimum & maximum Temperatures and rainfall was collected from State Data Centre. Various Droughtindices like Standardized Precipitation Index (SPI), Potential Evapo-Transpiration (PET) and Aridity Index (AI) were computedusing meteorological data of past 16-years.The results indicate that total agricultural vegetation during drought season was only 21.9 per cent (2002) which has increased to 58.7per cent during the normal monsoon season of 2018. The rainfall deviations were computed for various years and it was observedthat high negative rainfall deviations (-40 to -70%) having low rainfall occurrence were associated with negative SPI values rangingfrom -0.5 to -1.1 in Patan district. These positive rainfall deviations were associated with positive SPI values of 1.08, 0.57 and 0.62of respective years indicating moderately wet and mildly wet conditions. During drought year of 2002 total precipitation was veryless resulting in Aridity Index of 0.09 which is classified as hyper arid for the Patan District.