Why is rice a major commercial cargo on the Irrawaddy River?

Rice is a major commercial cargo on the Irrawaddy River primarily because the river's delta is one of the world's most significant rice-growing regions.1

The delta's environment, which benefits from more plentiful rainfall compared to the central dry zone, supports extensive cultivation of the crop. Consequently, the river serves as a vital transportation artery for this agricultural output: rice is collected in small boats throughout the delta region and moved to local markets, from which it is then shipped to Yangon for export. Additionally, about one-sixth of the total rice produced in Myanmar is grown in irrigated areas within the Mandalay, Sagaing, and Magwe divisions, further contributing to the volume of goods transported along the river system.213