Rice is an essential staple food for 3.5 billion people, nearly half of the world’s population. Yet, this popular food is accompanied by its negative impact on the environment. In particular, rice is responsible for 10% of global methane emissions. System of Rice Intensification (SRI), which promotes a farming system that produces more outputs with reduced inputs, can be a better farming practice that conserves the environment by lowering polluting inputs while sustaining food security. We explore how SRI works, the benefits that come with it, and the future outlook of this innovative farming method.
System of Rice Intensification (SRI) is an agro-ecological methodology used to increase the productivity of irrigated rice by changing the management of plants, soil, water, and nutrients. This farming system was developed in the 1980s in Madagascar by Father Henri de Laulanié, a French priest who spent 34 years working with farmers to improve rural livelihoods by increasing rice productivity.
SRI differs from conventional rice production in several aspects, from the age and number of seedlings, spacing of plants, water management, soil fertilisation, as well as the pest control mechanisms employed. Farmers will first raise seedlings in carefully managed nurseries, then transplant single, young (8-15 days old) seedlings at wide plant spacing (starting at 25×25 cm, but going up to 50×50 cm). Irrigation is then provided intermittently to avoid permanent flooding during the vegetative growth phase. Soil nutrients are added in organic forms such as compost instead of chemical fertiliser. Last but not least, intensive manual or mechanical weed control is done without herbicide use.
SRI is said to be a better farming practice than the conventional one as it is able to bring more environmental, economic, and social benefits.
1. Conserve Water Resources
The increase in global temperature has made water shortages more serious. It is estimated that 2.7 billion people worldwide currently suffer water scarcity for at least one month a year. Worse still, 15-20 million of the world’s irrigated rice lowlands are expected to face a certain degree of water scarcity by 2050. With the SRI method, however, water resources can be conserved. It is estimated that between 25% and 50% of the water used for paddy cultivation is saved under SRI. Using less water for rice production can free up water for other crops, promoting crop diversification.
2. Reduce Methane Gas Emissions
Agricultural activities, including farming on inundated rice fields, release a huge amount of methane, a major greenhouse gas that is 310 times more impactful than carbon dioxide on global warming. In fact, rice is responsible for 10% of global methane emissions and as much as 25-33% of the total methane emissions of the world’s major rice producer – Southeast Asia. The continuous flooding and inundating of fields deprive the soils of oxygen, which is conducive to producing methane. It is estimated that about SRI can save at least one-third of methane emissions, when flooded rice fields are drained at least once during the growing season.
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3. Reduced Use of Nitrogen Fertilisers
Nitrogen fertilisers are commonly used to sustain crop yields. Yet, the nitrogen released from them will exacerbate global warming, result in acid rain as well as pollute drinking water sources. With the continuous increase in demand for fertilisers, the nitrogen released into the atmosphere and waterways is projected to double by 2050. Under SRI, these fertilisers can be substituted by organic matter, a much more environmentally friendly alternative, resulting in a 20%-30% reduction in chemical fertiliser compared to traditional rice cultivation methods.
As plants are stronger and more deeply rooted, the SRI crop also stands to show greater resilience towards natural hazards such as drought, strong winds and storms, which are becoming more frequent and extreme because of climate change.
Economic and Social Benefits
SRI enables farmers to produce more outputs with reduced inputs. It is estimated that SRI can lead to a 90% reduction in seeds, a 23% reduction in cost, as well as a 68% increase in income for farmers per hectare. Thus, while the costs of seeds, synthetic fertilisers, herbicides, and pesticides decrease, more output is generated and can be sold to consumers.
Having lower expenses, farmers can produce more rice, improving both their income and food security while further benefiting their health by using fewer agrochemicals.
With all these benefits brought by SRI, many countries, especially those that rely on rice as a staple food such as India and Indonesia, have been adopting SRI extensively, as well as actively promoting it to farmers. Countries that actively support SRI include Kenya, Peru, Nepal, and Malaysia.
Figure 1: Global Adoption of SRI in 2018
System of Rice Intensification in Nepal
Nepal is vulnerable to food insecurity. 2017 data showed that, out of Nepal’s 75 districts, 38 suffered from food deficiency. The situation is even worse during droughts periods. Rice production in Nepal is averaging about 5 million tons as only 18% of the land receives adequate irrigation. Rice deficit reaches about 1 million annually even during years with good monsoons. Rice yield in Nepal dropped by about 5% in 2015 from the year prior due to an extensive drought.
SRI is a valid and sustainable solution deployed to increase the country’s food supply. For this reason, the government has promoted several programs to promote this farming method across the nation.
In 2015, the Mega Rice Production Program (MRPP) was launched in 15 districts of Nepal, and further expanded to 35 districts in 2016. The program emphasises wider spacing of plants, line transplanting, and mechanical weed management, integrating SRI principles into the conventional rice production system.
In 2017, SRI continued to help increase rice production. Crop yield had doubled in many places while using half the amount of seedlings and less water. The Mahadevsthan village, located in central Nepal, had reported to experience an average yield 30% higher than farmers using standard practices after adopting SRI. In some cases, yield increases were as high as 62%.
In 2018, the Lutheran World Federation programme in Nepal, together with the local NGO Digo Bikash Samaj-Kailali, introduced SRI methods to marginalised households. An initial training was given to 30 farmers, who later assisted in farmer-to-farmer training. The increase in yield compared to conventional practices had given enough rice to extend household sufficiency of basic grain by three months.
System of Rice Intensification in Malaysia
With the introduction of SRI, the paddy yields in Malaysia almost doubled between 1980 and 2009, increasing from 1,85 to 3,68 tons per hectare. Yet, Malaysia’s rice production has only achieved a self-sufficiency rate of about 70% in 2022, and has always been dependent on imported food as its own supply could not sustain the needs of the local demand.
Several programmes and projects have been carried out in recent years to promote the use of SRI in Malaysia.
In 2018, a two-day workshop held by World Wide Fund for Nature (WWF) Malaysia took place in Long Langai village in Sarawak, encouraging and promoting the use of SRI. Basic SRI training was given, while information on how to use simple ingredients to substitute commercially-produced fertilisers was also provided. Participants were also urged to apply for myOrganic certification under the Department of Agriculture. The certificate recognises farms that operate organically in the production, processing, handling, labelling and marketing stage, making their agricultural products easily recognisable and competitive on both domestic and international markets.
The SRI-Mas, short for “The Malaysian Agroecology Society for Sustainable Resource Intensification”, attended the 5th International Rice Congress held in Singapore in October 2018. In addition to the SRI presentation made during the conference sessions, SRI-Mas participated in a side event on SRI Research that provided an overview of global research on this farming method. 33 published scientific researches were later included in the Global SRI Research Network’s Malaysia collection.
In 2019, SRI training was given in Tanjung Karang through the Farmer Field School Project. About 40 participants attended the training, which was held at the new Sawah Sempadan SRI Learning Center. This one-day course provided information on the topic of SRI plant establishment and pest control through good SRI management and ecology-based solutions.
Future Outlook: SRI-2030
System of Rice Intensification continues to develop, with numerous research and programmes expected to be conducted in the coming years. SRI-2030 is one of the many future projects that aims to help promote SRI. Initiated by the Homeland Conservation, SRI-2030 aim to rapidly expand the use of eco-friendly agricultural practices around the world, particularly SRI. Works of millions of farmers in over 60 countries, and more than two decades of research have been built under SRI-30.SRI-2030 future targets included increasing the currently estimated 6.7 million hectares of land under SRI cultivation to 50 million hectares by 2030. This can be achieved by uniting governments, institutions, agencies, and individuals worldwide. It is estimated that the extra 1 billion tons of rice yield created combined with reduced inputs will generate an extra US$275 billion in profits for farmers by 2030, and $1.6 trillion by 2050.
All in all, the System of Rice Intensification is a great solution that can help reduce methane emissions from rice cultivation as well as improve food security. More research can be done to further boost the productivity of the SRI method, for example, on how technology can be used to further increase crop yields. Government supports and funding is also crucial in the development of SRI. Organisations and NGOs can also continue to provide programmes and courses to educate local farmers on some major principles of SRI.
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