Prospects of Crop and Forage Production in Coastal Saline Soils of Bangladesh

Abstract

Of 2.83 × 10⁶ hectares (ha) coastal area of Bangladesh, about 1.0 × 10⁶ ha is suffering from various levels of salinity. During monsoon, rice can be grown in these areas due to rainfall-induced natural leaching. In dry seasons, soil salinity increases in the soil profile and hence the entire coastal saline belt remains fallow. Considering this, International Center for Biosaline Agriculture jointly with Bangladesh Agricultural Research Institute initiated a project to grow cash and forage crops using irrigation and water management technologies in the coastal saline soils.

In 2007–2008, an initial pilot assessment was made and basic soil properties were determined in Satkhira District, where soil salinity (EC_e 11 dS m⁻¹) was recorded in dry months (March–April). Tomato, cowpea, and barley were used as test crops and harvested rain water was used for irrigation. Tomato crop with drip irrigation on mulched raised beds produced 55–66 t ha⁻¹ yield, which is 3.13–3.36 times of control treatment (flat lands with traditional can irrigation). A net return of US$ 2,658–3,559 ha⁻¹ was obtained which is 5.76–5.92 times more than the control treatment. The hosepipe irrigation in mulched raised bed gives net return of US$ 2,696–3,610 ha⁻¹, about 5.84–6.00 times more than the control treatment. These returns are higher than those obtained from drip irrigation due to less investment in irrigation setup. Fodder crops (i.e., cowpea and barley) were also found profitable. These were irrigated by both fresh and saline water using hosepipes with different irrigation scheduling. The net returns of cowpea and barley were about 4.00–4.23 and 2.11–2.60 times more than the control treatment, respectively, in various locations. The study indicates that 770,000 ha saline coastal land (EC_e ≤ 12.0 dS m⁻¹) has the potential for crop and fodder cultivations through proper irrigation and soil management practices.