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Land use refers to how the surface of a designated area is utilized, encompassing both developed and vacant lands. The intricate interplay between population growth and the availability of natural resources gives rise to diverse challenges that are exhibited in the recharge of groundwater. This research was conducted in the Koraiyar Watershed, Coimbatore District, Tamil Nadu, India. The change in the land use land cover (LULC) was detected by digitizing the linear imaging self scanning sensor (LISS) III and LISS IV satellite images for the years 2000 and 2011 using the maximum likelihood classification algorithm. LANDSAT-8 OLI data were processed for the year 2020. The study area has subsequently undergone an assessment of groundwater levels to determine the impact between groundwater and land use land cover. The result of the study indicates a continuous decrease in the wet crop area, which is the effect of the gradual depletion of groundwater resources. Along with this, the narrowing of the water bodies and increased areas of dry crops, industrial areas, and quarries are also responsible for lowering groundwater table depletion and contamination. Settlements increased from 39 to 49 km2 from 2000 to 2011 and then gradually increased by 50 km2 in 2020 to meet the demand of the population. From 2000 to 2019, the groundwater level has been declining with respect to the LULC pattern. The increase in concrete platforms in the study can affect the infiltration. Thus, the study can aid in developing water management strategies and decisions for governmental and non-governmental policymakers.

The deficiency in rainfall leads to meteorological droughts. Its manifestations are visible both in the vegetation cover and soil moisture. The present study assessed the characteristics of agricultural drought following meteorological droughts. The study also assessed the severity of meteorological droughts and their manifestation on the agriculture and soil moisture in a semi-arid area. The study has been carried out for the Malaprabha sub-basin which partly covers three districts of North Interior Karnataka, India. India Meteorological Department’s (IMD) criteria have been used to identify the drought years, and its severity has been assessed through the Standard Precipitation Index (SPI). The IMD’s monthly rainfall data were used to identify the drought years and periods for the region. Among the drought years, the mild, moderate, and severe drought along with deficit and excess rainfall years were considered to assess and characterize the soil moisture conditions and the agricultural drought. The satellite image based indices for these selected years were constructed to determine the soil moisture conditions and the agricultural drought severity. The Temperature-Vegetation Dryness Index (TVDI) was used to determine the soil moisture conditions. The indices employed to determine the agriculture drought are NDVI, Thermal Condition Index (TCI), Vegetation Condition Index (VCI), and Vegetation Health Index (VHI). These satellite-based indices were calculated using the Landsat images of the selected drought and non-drought years. The results showed that the seasonal and annual drought are frequent in the study area. There are spatial and temporal variations in the drought years and their severity. The satellite-based indices clearly indicate the spatial variation in the agriculture droughts and its intensity. It has been found that the impact of drought on agriculture has significantly reduced due to the development of well-irrigation in the sub-basin. VHI is more appropriate in determining the agricultural drought and its characteristics.