Rattan Lal, this year’s winner of the World Food Prize, is the fourth soil scientist awarded the $250,000 equivalent of the “Nobel Peace Prize in Agriculture.” The India native is director of the Carbon Management and Sequestration Center at Ohio State University, which studies how to use sustainable land management to not only reduce atmospheric carbon dioxide levels, but also enhance food security, improve water use efficiency, and reduce poverty.
Working across four separate continents, Lal has spent five decades researching how soil can help solve a number of societal woes. His work has improved the livelihoods of millions of smallholder farmers around the world and saved hundreds of millions of hectares of tropical ecosystems. Lal may have grown up on a small farm in India, but his soil restoration research has informed politicians and underpinned several of the United Nation’s sustainable development goals. In 2007, he was one of the recipients of the Nobel Peace Prize for contributions to the Intergovernmental Panel on Climate Change (IPCC) reports.
He spoke to Civil Eats about how soil alone can’t solve climate change, but is a vital part of the solution.
What does it mean, as a soil scientist, to win the World Food Prize?
Personally and professionally, it means quite a lot to win what is considered the top prize in agricultural sciences. When I got the call, I had to make sure I wasn’t asleep and no one was pulling my leg. It is auspicious timing for a few reasons. I’m the 50th awardee, only the second soil scientist, and I received the award on the 50th anniversary of Norman Borlaug’s Nobel Peace Prize—the only agricultural scientist to receive the Nobel. Plant breeders typically win this prize because they are in a position to say that millions of acres of land were saved using their “miracle” variety. Plant breeding is incredibly important, but elite varieties are most effective when they are grown in healthy soil.
What soil protection laws would you like to see enacted?
In the 1960s, we enacted a Clean Air Act and Clean Water Act. We do not have a Clean Soil Act. How is it possible to have clean water or clean air without healthy soil? It’s time that our policymakers wake up. We need the trinity—water, air, and soil—protected. We need a Soil Management Act or Soil Health Act. I’ve also argued that soil is a living thing, and therefore has rights. If every living thing has legal rights, why not soil? I raised these issues in 2007, when I was the president of the Soil Science Society of America. A soil protection resolution was approved unanimously by the U.S. Senate in June 2008, but has not yet been translated into an act.
What drives your research?
The question that I have really focused on is how to achieve food and nutritional security for the growing population, while at the same time improving water quality and air quality and mitigating climate change. It’s not either-or. We have to have both. The problem is technology without wisdom. We have to use technology—wisely. We keep blaming agriculture for environmental problems. How can you blame agriculture as long as you like to eat food three times a day? We have an obligation to make agriculture a solution.
Soil is one of five big carbon sinks on earth, and it traditionally held a great deal of carbon that has now entered the atmosphere. Can you put into perspective how much carbon has been lost from soils globally?
I calculated that 135 gigatons have been lost from agricultural soils. To put that into perspective, the total fossil fuel emissions each of the last few years has been 10 gigatons. Surprisingly, at the same time, another scientist, Jonathan Sanderman at Woods Hole Research Center, also initially calculated 133 gigatons. Since then, Sanderman has changed it to 110 after updating his computer program. It’s anywhere between 110-130. If you combine how much carbon has been lost from soil and vegetation together—for example from cut trees or drained wetlands—we have lost more than 500 gigatons.
How important is soil as a climate change solution?
The climate problem is so humongous, it cannot be solved effectively unless agriculture and soil are part of the overall agenda. Soil, by itself, cannot solve the climate problem, but it has to be part of the solution. The most economic, natural, low-hanging fruit is restoring soil.
I published a paper showing that soil can sequester about 180 gigatons. Some soils are more degraded than others. Vegetation can add back another 150 gigatons, so, in total, about 330 gigatons could theoretically be added back between 2020 and 2100. If it happened, it would draw down the atmospheric carbon dioxide amount by about 150 ppm. Even if only one-third of that happened, it is still more than 50 ppm.
(Editor’s note: As of February 2020, the planet’s atmosphere contained 414 ppm of carbon dioxide. The carbon dioxide level has risen around 50 ppm since the late 1990s. For climate scientists, 400 ppm, a number that the planet surpassed in 2017, was as a “clear red line into a danger zone of climate change.”)
Do you have any concerns that the ability of regenerative agriculture to sequester carbon long-term has been oversold?
It is possible. Soil is like a cup. You [can] put into a cup [only] as much as you drink out of it. The best rate of carbon sequestration in Midwest under ideal conditions is about 1,000 pounds per acre. I’ve heard people saying they can do three times that. I don’t want to discourage their enthusiasm, but we have to be realistic. It is our responsibility to make sure that regenerative practices, be they cover crops or no-till farming, work.
Do you think we need more intensive monitoring to sustain a robust carbon market?
In the last couple of decades, tremendous progress has been made in monitoring soil carbon. That said, we don’t need to monitor every bit of soil. Recall the very successful Conservation Reserve Program. At its peak, in both 1994 and 2007, the government had enrolled at least 35 million U.S. acres in it and paid farmers to prevent soil losses from highly erodible lands [by removing the land from agricultural production and planting species on it that would improve its environmental quality]. Did we monitor to see if erosion control happening? No. We assumed that if we set aside the land and didn’t plow it, erosion was controlled. The same thing applies here.
We can assume, given the same soil type, climate, and management, that farmers get about the same carbon storage give or take 2 to 5 percent. The idea that we have to monitor every acre, to me, does not make sense. I’ve been listening to the same argument since 1992, “Do you know how to measure it?” When I see the idea that we have to monitor every acre, I ask why not monitor every inch?
What incentives do you think farmers should receive to adopt regenerative practices?
I calculated farmers should be compensated at $16 per acre per year for the ecosystem services they provide. To arrive at that number, I calculated the value of the crop residue and nutrients required to produce one ton of humus, and came up with $123/ton of carbon. The final number corrects for the assumed net gain of carbon in the Midwest on a per acre basis. Farmers must be given transparent, just, and fair pay. It should not be decided by the demand and supply for carbon.
Farmers should be paid because we’re asking them to do things to help the planet, society, and ultimately themselves. The societal value of carbon is not the economic value of carbon. The Chicago Climate Exchange trading of carbon dioxide fell to 5 cents before it closed in 2010. That is undervaluing a precious resource. When we undervalue a resource, we degrade it and ruin it.
How has your work influenced policymakers?
In addition to working on the IPCC and with the FAO, a few politicians have reached out to me specifically over the years. Stéphane Le Foll, then the French minister of agriculture, who promoted the COP 21 in Paris in 2015, the Climate Summit, came to my lab that year. From that discussion, he created the “4 per 1,000” Initiative to increase soil carbon at an annual growth rate of 0.4 percent through implementing conservation farming practices. I’m a strong supporter of that program, although I think they may be overly ambitious. If we can scratch .1 percent per year, it would be good.
I was asked to help launch Global Soil Week, an international forum to promote conversations between researchers, farmers, government, and business. The President of Iceland, Olafur Grimsson, and the President of Bangladesh, Iajuddin Ahmed, himself a soil scientist, attended the Soil Science Society of America meeting in 2007, when I was president of the organization. They discussed how their countries could serve as models of climate change impacts.
Can the world feed 10 billion by 2050?
I am concerned with the suggestion that if we are to feed 10 billion by 2050, we need another 200 million hectares of land. I’m absolutely against it. We have plenty of land [to achieve this goal]. We [just] do not manage it properly. My goal is to convince people to save land and water. We are using 70 percent of water for irrigation. We can reduce total water use through drip irrigation. We are using 200 million tons of fertilizer. There’s no reason why we cannot improve efficiency and reduce those rates.
This interview has been edited for brevity and clarity. All photos courtesy of the World Food Prize.
This article was updated to correct the fact that Dr. Lal is the fourth soil scientist to win the World Food Prize.