Agriculture Transforms from "Climate Villain" to "Key Solution" — "3N Agriculture" Protecting Nature, Carbon, and Nutrition Simultaneously Changes the Future of Our Tables

1. Why is agriculture called the "culprit of climate issues"?

When we hear "CO₂ emissions," we tend to immediately think of power plants, cars, and airplanes.

However, recent studies suggest that the entire food system accounts for about one-third of global greenhouse gas emissions. This includes not only production on farmland but also the manufacturing of fertilizers and pesticides, processing, transportation, refrigeration, retail, home cooking, and food waste.publications.jrc.ec.europa.eu+4FAOHome+4Nature+4

Emissions from agriculture have several characteristics.

• Methane emissions
  A large amount of methane (CH₄) is released from the burps of ruminant animals (such as cows, sheep, and goats) and anaerobic decomposition in rice paddies. Methane is a more potent greenhouse gas than CO₂.Phys.org
  
  

• Nitrous oxide (N₂O) emissions
  Nitrous oxide is generated in soils treated with chemical fertilizers and livestock manure due to microbial activity. This gas also has a stronger greenhouse effect compared to CO₂.Phys.org
  
  

• CO₂ emissions from land-use changes
  When forests and grasslands are cleared for farmland, the carbon stored in the soil and plants is released into the atmosphere, and the "places that can absorb and store carbon" are simultaneously lost.

Furthermore, it is estimated that about half of the world's "habitable land (excluding glaciers and deserts)" is used for agriculture.datawrapper.de+4Our World in Data+4Our World in Data+4

Given that agriculture occupies such a large area, its practices significantly impact not only the climate but also nature, such as forests, grasslands, and wetlands, and the biodiversity that inhabits these areas.

In other words, agriculture is a "very important entity both as a source of emissions and as a driver of environmental destruction."

2. Nevertheless, agriculture is also a "victim"

On the other hand, agriculture is one of the industries most affected by climate change.

• Crop failures due to abnormal droughts and heavy rains

• Stress and death of livestock due to heatwaves

• Destruction of fields, facilities, and infrastructure by floods and typhoons

These risks are hitting agricultural sites not only in Japan but worldwide.Phys.org+1

Moreover, many farmers operate on thin profit margins, and consecutive climate disasters can often force them out of business.

In other words, agriculture is in a dual position as "both a perpetrator of the climate crisis and one of its greatest victims."

3. COP30 and the global debate on "what to do with agriculture"

This article introduces the context of the United Nations Framework Convention on Climate Change Conference of the Parties (COP30) to be held in Brazil. In recent years, "agriculture and food" have finally begun to be treated as a serious theme in international negotiations.Phys.org

• Chapters on agriculture and land use are now being included in the **NDCs (Nationally Determined Contributions)** submitted by each country.

• Meanwhile, many lobbyists from major agribusiness companies attend the venue, working to avoid regulations unfavorable to them.

• Outside the venue, small-scale farmers, indigenous groups, and civil society organizations are raising their voices for **"low-impact agriculture," "agroecology," and "climate justice."**

Thus, "how to change agriculture" has become a political theme intricately intertwined with corporate profits, farmers' livelihoods, consumer eating habits, and climate goals.

4. What is "3N Agriculture" based on the three Ns?

Researchers in Australia propose changing agriculture simultaneously from the following three axes to organize this complex situation.Phys.org

1. Net Zero

   • The concept of minimizing greenhouse gas emissions from agriculture while storing carbon in the soil, etc., to bring the balance of emissions and absorption closer to zero.

2. Nature Positive

   • The idea of transforming farmland from a "place of environmental destruction" to a place that restores and enhances biodiversity and ecosystem services.

3. Nutrition Balance

   • Producing food with excellent nutritional balance, including not only calories but also vitamins, minerals, and proteins, with a view to correcting health disparities.

This is collectively called **"3N (Net Zero, Nature Positive, Nutrition)"** and is proposed as a framework to simultaneously achieve emission reductions, nature conservation, and health improvement.PMC+3Phys.org+3Nature+3

Below, we will look at each of these three in detail.

5. N1: Agriculture aiming for Net Zero

5-1. Reducing "wasteful fertilizers" and "wasteful emissions" with precision agriculture

The first pillar is "Net Zero."

Much of the emissions from agriculture come from livestock methane, nitrous oxide from fertilizers, and CO₂ emissions from soil. Precision agriculture is gaining attention as a smart way to reduce these.Phys.org

• Real-time monitoring of soil moisture and nitrogen levels with soil sensors

• Visualizing crop growth conditions with drones and satellite images

• Applying fertilizers and water only where needed, in the necessary amounts, and at the right timing

This allows for a departure from the method of
"just spreading the same amount of fertilizer all over the field"
, achieving cost reduction and emission reduction simultaneously.

In Japan, drone spraying and variable fertilization technology are gradually being introduced, mainly in large-scale rice farming and facility horticulture, but pricing and support systems that reach small and medium-sized farmers are still in progress.

5-2. Changing the way fertilizers are made

The currently dominant nitrogen fertilizers are produced by the "Haber-Bosch process," which requires a large amount of fossil fuel energy and emits a lot of CO₂ during manufacturing.

Researchers are exploring methods to make fertilizers directly from atmospheric nitrogen using renewable energy and new technologies. If realized, this could significantly reduce the "invisible emissions" of agriculture.Phys.org+2EASAC+2

5-3. "Banking" carbon in the soil

For Net Zero, it's important not only to reduce emissions but also to **store carbon in the soil, or "carbon banking."**

• Planting green manure (clover and leguminous cover crops) and returning organic matter to the soil as roots and residues

• Incorporating residues (such as straw) into the soil without burning them

• Introducing "no-till farming" to minimize tillage and avoid disrupting soil structure

This increases the organic matter in the soil and allows for long-term carbon sequestration. Research on regenerative agriculture also shows that such approaches contribute to improving soil carbon storage, water retention, and biodiversity.EASAC+4Nature+4ScienceDirect+4

5-4. Reducing livestock methane with "feed innovations" and clean tractors

To reduce