A critical systematic insight into alternate wetting and drying irrigation for a sustainable solution in paddy fields

Growing global food demand amid dwindling water resources and climate change has shifted traditional rice cultivation systems to sustainable alternatives. Among these, alternate wetting and drying (AWD) irrigation has sustained prominent potential for environmental mitigation, water and agricultural productivity. This comprehensive systematic review integrates 463 peer‑reviewed studies (2004–2024), using a multi‑tool bibliometric and text‑mining framework to unravel two decades of scientific progress, dominant research trajectories, and persistent uncertainties surrounding AWD adoption. Keyword evolution, clustering, and topic modeling reveal a decisive shift from early investigations on soil aeration and aerobic rice toward contemporary emphases on water productivity, greenhouse gas (GHG) mitigation, nutrient-use efficiency, and yield stability. Meta‑analysis of these modeled sustainability themes demonstrated that AWD significantly enhances water productivity (+0.18 ± 0.04 kg grain m −3 , P < 0.0001) while maintaining statistically comparable grain yields to continuous flooding (CF), despite substantial heterogeneity driven by soil type, drying intensity, cultivar choice, and nutrient management. AWD consistently reduces CH 4 emissions (-199.21 kg CH 4 ha −1 , P < 0.002) and lowers net global warming potential (-4.14 t CO 2 -eq ha −1 , P < 0.0002), but N 2 O responded a non-significant substantial contextual variability. However, AWD contextual synergies with zeolite, biochar, optimized N placement, and drought‑tolerant cultivars resulted in yield amplification, nutrient recovery, and GHG mitigation. Adoption caveats include labor-intensive monitoring and irrigation infrastructure requirements, socio-economic barriers, and geographic concentration of research in Asian regions. These gaps warrant regional‑specific AWD intensity calibration and decision-support tools development that account for local hydrological, climatic, and socio-economic realities.