Assessment of Water use Efficiency and Rational Irrigation Consumption across the Regions of Kazakhstan under Climate Variability

Efficient water management in irrigated agriculture is a cornerstone of sustainable development in arid and semi-arid regions.Kazakhstan, with over 2 million ha of irrigated land, faces growing competition for water under climate variability, land degradation, and energy-intensive irrigation systems.This study presents an integrated evaluation of irrigation water-use rationality and efficiency across sixteen regions of Kazakhstan during 2022-2024, based on a newly proposed Integral Rationality Index (IRI) that synthesizes climatic, hydrological, agronomic, and managerial indicators.Data were compiled from the Ministry of Agriculture of the Republic of Kazakhstan (2024) and regional Basin Inspectorates, complemented with recent FAO, IWMI, and OECD datasets.The IRI provides a 1-5 rating scale capturing water availability, losses, modernization, and economic productivity.Results reveal pronounced regional disparities: high rationality (IRI > 3.5) in East Kazakhstan, Abai, and Zhetysu Oblasts driven by modernization and stable hydrology, versus low scores (< 2.8) in Kyzylorda and Atyrau Oblasts linked to heavy reliance on transboundary rivers and waterintensive crops.The study further identifies modernization and digitalization as the most decisive factors, surpassing precipitation influence.Findings align with global trends reported by FAO (2023) and IWMI (2021), confirming that efficiency gains depend primarily on technology adoption and governance, rather than climate alone.This framework supports national water-security planning and SDG 6.4 targets, offering practical recommendations for differentiated water-use policy across Kazakhstan's agro-ecological zones.