Rice is a global cuisine staple, sustaining food for nearly two thirds of the world’s population. Originating in China more than 5,000 years ago, rice spread to ancient Greece and then onto the Nile Delta, reaching the New World in the 17th century .
While rice is a core part of many people’s diets, it is estimated that it takes 5,000 liters of water to produce one kilo of rice with 11% of the world’s arable land given over to rice cultivation . Rice’s extraordinary water footprint is primarily owed to the fact that rice is normally covered with water. This helps suppress weed growth, but it also uses enormous quantities of water and increases methane emissions when plant matter decomposes in flooded fields.
A new method of cultivating rice
Methods are however now emerging to limit rice’s water footprint. One of the most promising approaches was developed about 25 years ago by farmers in Madagascar who decided not to flood rice paddies continuously. The concept was originally developed in the early 1980s by Fr. Henri de Laulanié, S.J., a trained agronomist, who came to Madagascar from France in 1961 and spent 34 years working with local farmers to improve their agricultural systems. His work culminated in the development of a method for cultivating rice which rather than relying on flooding rice paddies uses aerated soil.
This farming approach is based on four main key principles:
- Transplanting rice seedlings when they are very young and spacing them farther apart on a regular grid rather than randomly. By doing this, there is less crowding, root systems are stronger and farmers can use manual weeders.
- Using integrated pest management instead of herbicides.
- Enriching soil with organic matter rather than synthetic fertilizers.
- Applying water intermittently rather than flooding rice fields.
- Using manual weeders to aerate topsoil and remove weeds .
This method of farming created deeper roots and larger plants that produced heavier grain. In addition to requiring less water, this method also minimises land preparation and use of fertilisers . Today, 2.5 million farmers in 50 countries have adopted this method given the productivity gains and the decrease in resource use. Proponents of this method argue that farmers save 50% less water and 90% less seed, even those results yield up to three times compared to conventional farming methods . In addition, this method improves root growth and enriches soil.
This farming method is called the system of rice intensification (SRI) and even though companies are already engaging in promoting its benefits more widely, researchers have also noted that some of the claims in terms of the method’s productivity have not been replicated.
Regardless of this scepticism, governments in developing countries which depend on rice for food and trading purposes, have supported the SRI method. According to Oxfam, Vietnam’s Plant Protection Department confirms that farmers who use SRI significantly reduce the use of chemicals, thus growing healthier food, improving soil quality, and protecting farm biodiversity. They estimate that SRI farmers increase their yield by 500 kilograms thereby earning extra income of $130 per hectare in just one cropping season. This is a significant sum for Vietnam where average income is around $1,200 .