What Contribution Can Surface Water Irrigation Make to Sustainable Crop Intensification in Bangladesh’s Feed the Future Zone?

Abstract

Global food requirements are projected to increase until 2050. In South Asia, averagewheat, maize and rice yields have however increased by only 2.2 percent, 1.4 percent and 1.3 percent, respectively, since the 1960s.1 Rather than raising yield, crop production can be increased by expanding cultivated land area, though this has undesirable environmental outcomes such as biodiversity loss. The potential for agricultural expansion in South Asia is also limited because most arable land is cropped for at least part of the year, usually during the monsoon. Farm area per capita in South Asia has also shrunk by 63 percent since 1961, to approximately 0.1 hectare per person. 2 Sustainable intensification (SI) has been proposed as an alternative to area expansion. SI aims to augment land productivity by increasing resource use efficiency while minimizing environmental trade-offs. 3 An important SI strategy is increasing the number of crops grown per year on the same land, thereby raising yield per unit of area-time, while minimizing land expansion. 4 Achieving such ‘double cropping’ will often require irrigated dry season cropping to overcome moisture constraints to adequate yields.