Replacing rice will improve India’s climate resilience

Rice field in Karnataka (Image: Guldem Ustun, Flickr Commons, CC BY 2.0)
Rice field in Karnataka (Image: Guldem Ustun, Flickr Commons, CC BY 2.0)

A new study finds that introducing coarse cereals such as millet and sorghum could improve India’s national food supply in many ways. The study by the Data Science Institute at Columbia University found that India’s agricultural policies have largely focused on the single objective of maximizing production, and not enough attention has been given to nutrition, climate, and environment.

Dominance of rice post Green Revolution

The Green Revolution promoted the use of high-yielding seed varieties, irrigation, fertilizers, and machinery and emphasized maximizing food calorie production, often at the expense of nutritional and environmental considerations. As a result, rice and wheat now contribute three-quarters of the country’s cereal production (44% and 30%, respectively), and cereals continue to comprise much of per capita calorie consumption - 60% in urban and 70% and rural households. For the monsoon season in particular, these trends have led to a homogenization of cereal production toward rice.

Between 1966 and 2011, the total cropped areas for monsoon cereals remained nearly constant, while harvested areas dedicated to monsoon rice increased from 52% to 67%. Owing to the increased share of monsoon cereal area dedicated to rice - often in places where agro-ecological conditions are not well suited because of example, they face water scarcity - there have been a large scale decline in the area used for coarse cereals such as finger millet, pearl millet, and sorghum as well as dietary shifts away from their consumption.

This growing dominance of rice in monsoon croplands is due to the underlying policy regime that has made rice cultivation more profitable, expanded use of irrigation and other agricultural inputs, and focused investments in research and development. Yet, coarse cereals have higher nutritional quality, greater resource use efficiencies per unit of production, and are less sensitive to climate variability as compared to rice, even after controlling for areas where rice production occurs with that of coarse cereals.

India can sustainably enhance its food supply if farmers plant less rice and more nutritious and environmentally-friendly crops such as finger millet, pearl millet, and sorghum, according to the study published in the Proceedings of the National Academy of Sciences.

Diversifying crop production in India, in this case replacing some rice -- with millets and sorghum, would make the nation’s food supply more nutritious while reducing irrigation demand, energy use, and greenhouse gas emissions. Such diversification of crops would also enhance India’s climate resilience without reducing calorie production or requiring more land.

The study states that multidimensional approaches to food production challenges can identify win–win scenarios where we think beyond just increasing food supply and also find solutions that can benefit nutrition, farmers, and the environment.

The need for targeted interventions

A district-level analysis of the data, which optimized national outcomes, allowed for the identification of specific parts of India where increased coarse cereal production would reap the largest benefits. As such, the benefits of this strategy were not evenly spread across the country, with much of the improvement occurring only in certain states.

Certain states contributed disproportionately to these benefits:

  • Across the dimensions of iron supply, water, energy, and greenhouse gas (GHG) emissions, Madhya Pradesh, Uttar Pradesh, Bihar, Jharkhand, Andhra Pradesh and Tamil Nadu were likely to see much of the improvements.
  • Bihar alone contributed 33% of the improvement in climate resilience.
  • Bihar, Tamil Nadu, and Uttar Pradesh were responsible for greater than 50% of the benefits across all dimensions.
  • Assam, Himachal Pradesh, Kerala, Odisha, Punjab, and West Bengal would see few or no improvements.

Overall, these results suggest that targeted interventions in only a few states can produce substantial benefits for national-level nutrient supply, climate resilience, and the environment. 

In the context of widespread malnutrition, groundwater depletion and the need to adapt to climate change, increasing the supply of nutri-cereals may be an important part of solving India’s food shortage. The study team performed a series of optimizations to either maximize the production of important dietary nutrients (i.e., protein and iron), minimize GHG emissions and resource use (i.e., water and energy), or maximize resilience to climate extremes. They found that planting more coarse cereals such as millets and sorghum could improve India’s national food supply in myriad ways.

On average, it would increase protein by 1 to 5 percent; increase iron supply by 5 to 49 percent; increase climate resilience (1 to 13 percent fewer calories lost during a drought), and reduce greenhouse gas emissions by 2 to 13 percent.

The diversification of crops would also decrease the demand for irrigation water by 3 to 21 percent and reduce energy use by 2 to 12 percent while maintaining calorie production and using the same amount of cropland.

Dietary preference for coarse cereals already exists

Populations in these identified baskets of coarse cereal cultivation tend to largely favour consuming these crops. Pearl millet is part of the local diet in the northwest, just as sorghum is consumed in central India.

Thus, the finding that drastic shifts in cropping patterns would not be required to achieve substantial benefits for nutrition supply, climate resilience, and the environment is promising from both production and consumption perspectives.

At the same time, additional expansion of coarse cereals to deepen the benefits - especially in places such as Punjab where rice is particularly high yielding but where unsustainable resource use is widespread - would require investments to improve yields of coarse cereals and interventions that account for and prioritize finite resource availability (e.g., minimizing water scarcity or groundwater depletion) while still assessing outcomes across multiple dimensions.

Need to correct market distortions

Despite the multiple co-benefits that we observe, economic factors play a key role in determining a farmer’s crop choice. They can probably explain a lot about the historical shift toward rice and wheat cultivation. The Indian government sets guaranteed minimum support prices (MSPs) and large procurement goals for rice and wheat, to supply national food security programs like the Public Distribution System (PDS). Coarse cereals have had minimal (if any) annual procurement targets.

These market distortions have made the production of coarse cereals less economically attractive until recently. The Indian government and several state governments (e.g., Karnataka, Odisha) decided to procure selected coarse cereals at MSP - a move aimed at simultaneously incentivizing their cultivation and meeting national commitments to double farmers’ income by 2022.

A key caveat in achieving the estimated benefits of cereal diversification is the extent to which agronomic characteristics will permit switches between crops. On the one hand, historical policy regimes have promoted the widespread cultivation of crops in places that may not have otherwise been agro-ecologically suitable or sustainable (e.g., rice in northern India).

On the other hand, certain areas where rice is currently grown (e.g., low-lying floodplains) may not be able to support the cultivation of coarse cereals. Assessments quantifying the range of biophysical conditions that can support the cultivation of each cereal will therefore be essential for understanding the potential magnitude of co-benefits from increased coarse cereal production.