From Vânia Pankievicz
How can you feed 7 billion people without harming the soil and the sea?
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As we know, it is actions that promote the sustainability of the planet, not wasting water, avoiding plastics, producing less waste and choosing renewable energy sources. But there are many others that can affect our lives. One of them, for example, is the biological fertilization of food. It’s not a popular topic, it’s not on the agenda, but regardless of a person’s eating routine, at some point they will need food grown with fertilizers. The problem is that the chemical additive has silently and continuously unbalanced the biosphere.
Since the Green Revolution, that is, since the 1960s, the mass production of these nitrogen additives has changed agriculture and increased food production colossally without necessarily multiplying the area under cultivation. However, the compost placed on the ground drains into rivers and seas, and the consequences can be catastrophic, as is the case in the Gulf of Mexico in the United States: from above we can already see the stain caused by the excess of additive becomes a food source for some organisms that grow wild and cause the death of other living things by consuming oxygen from the aquatic environment.
The high cost of these compounds and their form of production, which requires a large amount of natural gas, a non-renewable source, are additional complications. Not to mention that once these fertilizers are applied to the soil, if they do not penetrate the groundwater, they break down into greenhouse gases.
What should I do? Stop using fertilizers? However, they are not the villains of the story. Fertilizing the soil with nitrogen is a question of survival: how can you feed more than 7 billion mouths? One possible solution is to convert atmospheric nitrogen into ammonia.
Despite all this abundance of gas, plants do not absorb it directly from the air, so a conversion is required, which can be biological, physical, or industrial. In the biological field, specialized bacteria bind nitrogen and convert it to ammonia by transferring the compound into the soil or directly into the roots of the plant. In physics, lightning comes in contact with nitrogen in the atmosphere and forms nitrates. A large amount of natural energy is used in industry to produce nitrogen fertilizers.
Brazil has benefited from biological nitrogen fixation in soybean crops for over 30 years. Legumes’ molecular pathway favors interaction with these bacteria, the rhizobia, which make up 50% of the nitrogen used by plants. In other words, in Brazil 50% of the fertilizer is saved in soybeans, which makes this crop one of the most important in our economy. Grass plants like corn, wheat, and rice, three of the five most commonly produced worldwide, interact with other types of bacteria, associative bacteria, which bind nitrogen on a smaller scale compared to rhizobia.
Scientists around the world are working to improve the interaction of nitrogen-fixing bacteria with these grasses. Johanna Döbereiner, a Brazilian microbiologist, dedicated her life to researching these organisms. If the country is the largest soy producer in South America today, it has done a lot thanks to its research into bacterial vaccines, which are efficient alternatives to the heavy use of chemical fertilizers. Sugar cane production, of which Brazil is the largest exporter, also benefited from the results of its research – this culture uses up to 60% of its nitrogen from vaccines.
The way our food is made is not sustainable and needs to be reinvented to meet demand. Investing in science and developing biological products should be on the agenda, as should public engagement in replacing plastic and fossil fuels. Solutions like these contribute to sustainable agriculture for future generations and must become increasingly popular.
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Vânia Pankievicz is a biologist, researcher and co-founder of GoGenetic, a biotechnology company founded at the Federal University of Paraná.
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