While the bulk of research on crop water productivity (WP) focuses on static cross-section analysis, this research
provides a spatio-temporal perspective. It estimates rice crop WP for 21 Bangladesh districts for 37 years;
explores WP variations among districts; and investigates causality involving WP, intensification and technological
variables; and groundwater irrigation and depth. It breaks new grounds by probing these significant but
unexplored issues.
Technological diffusion was the key factor explaining inter-district WP differences. The impact of agricultural
intensification on rabi (dry season) and kharif (wet season) crop WPs was positive and negative respectively.
Dummy variables typifying policy transition negatively impacted on WPs for both kharif and overall crops.
While rabi and kharif rice WPs grew with time, overall crop WP recorded the strongest growth. Rabi and overall
WPs were lower in salinity- and drought-prone districts covering 33% of Bangladesh's net cropped area (NCA).
In 90% of Bangladesh's NCA districts, technological diffusion caused WP. Causality existed between groundwater
irrigation and depth in 60% NCA. Despite significant potential to increase WP, increasing dependence on groundwater
appears unsustainable. Widespread diffusion of HYVs in the kharif season, and development of salinity and
drought-tolerant rice varieties could go a long way in sustaining rice WP.