Agricultural Intensification and Cropland Expansion in the Semi-Arid Foothills of Kirthar Range: Implications for Water Management and Food Security

This study explored cropland changes in the semi-arid foothills of the Kirthar Range, located in southern Pakistan. Utilizing the Normalized Difference Vegetation Index (NDVI) time series analysis on the Google Earth Engine (GEE) platform, changes in cropping patterns over the past three decades were investigated, assessing how water management strategies have driven agricultural expansion in the western part of the Dadu district in Sindh. The methodology included determining the number of cropping seasons and analyzing spatial and temporal changes in cultivated land through seasonal change assessment and crop classification. Seasonal aggregates were developed to map winter and summer crops for the past 30 years, from 1990-91 to 2020-21, after every five years for 1990-91, 1995-96, 2000-01, 2005-06, 2010-11, 2015-16 and 2020-21. From 1990 to 2021, the cropland area significantly expanded from 169 km² to 751 km²—a net increase of 582 km², reflecting a 78% growth. The area under single-season crops increased from 133 km² to 540 km², while double-season crops grew from 36 km² to 210 km², representing 75% and 83% growth rates, respectively. The driving factors behind this expansion and intensification of agriculture were the construction of water storage structures and the adoption of solar tube wells, all of which enhanced irrigation capabilities and agricultural productivity to meet rising food demands.