Managing Rice in an Era of Environmental Crisis:How New Fertilization and Irrigation Technologies Could Safeguard the Future

Amid the growing threats of climate change and the rapid rise in global food demand, rice paddies have once again come into sharp focus. The Intergovernmental Panel on Climate Change estimates that global food demand will increase by up to 70 percent by 2050. Behind this figure lies a critical reality: rice remains the primary source of energy for more than half of the world’s population.

Yet arable land is not expanding, while production pressure continues to intensify. In many major rice-producing regions—including eastern China—agricultural intensification has become the dominant strategy. Farmers rely heavily on large inputs of nitrogen fertilizer and continuous flooding to sustain yields. While effective in the short term, these practices leave behind serious environmental consequences. Greenhouse gas emissions rise, rivers become polluted, soils acidify, and the air fills with harmful fine particles.

When Fertilizer Can Regulate Itself

In recent years, a new innovation has begun to attract attention: controlled-release urea (CRU). This is no ordinary fertilizer. Encased in a protective coating, the nitrogen it contains does not dissolve immediately upon contact with water. Instead, it releases gradually, aligning more closely with the plant’s actual nutrient demand.

This targeted approach significantly improves nitrogen efficiency. Plant roots absorb nitrogen steadily, reducing losses to volatilization or runoff into nearby waterways. In several regions, deeply placing CRU beside rice plants has been shown to increase nitrogen use efficiency while cutting ammonia emissions by more than half.

For farmers, the benefits are tangible. Crops grow more consistently, yields improve, and costs decline as less fertilizer is wasted.

AWD: Smart Irrigation That Teaches Soil to Breathe

Beyond fertilization, water management plays a crucial role in maintaining productive and environmentally responsible rice systems. One of the most widely discussed techniques is Alternate Wetting and Drying (AWD). Simple yet highly effective, AWD avoids continuous flooding. Water is applied only when the soil truly needs it.

This approach allows the paddy soil to “breathe,” cycling between wet and dry conditions. As a result, water use drops significantly, disease pressure declines, grain quality improves, and methane emissions—typically high in flooded paddies—are substantially reduced.

However, every innovation brings new challenges. The alternating moisture conditions under AWD can increase emissions of nitrous oxide, a greenhouse gas far more potent than methane. In addition, nitrogen losses through volatilization and surface runoff may rise. This is where the need emerges for integrated fertilization and irrigation strategies that complement one another.

When Two Technologies Converge

Combining precisely placed CRU with the AWD irrigation system offers a promising pathway forward. CRU helps keep nitrogen available in the soil, preventing losses during dry phases or re-flooding events. AWD, meanwhile, conserves water and improves soil health without sacrificing productivity.

Field experiments reveal that this combination can significantly increase rice yields while simultaneously reducing harmful gas emissions and minimizing nitrogen pollution. Farmers benefit from higher and more stable harvests, while the environment gains cleaner air, clearer water, and healthier soils.

This approach also highlights a critical insight: nitrogen management is not just about how much fertilizer is used, but how, when, and where it is applied.

The Yangtze River Basin: A Living Laboratory for Future Agriculture

The middle and lower reaches of the Yangtze River provide a powerful real-world example of where challenges and innovation intersect. Hundreds of thousands of hectares of rice fields here depend heavily on nitrogen fertilizer to produce nearly half of the country’s rice output.

At the same time, the region faces some of the most severe consequences of agricultural intensification: declining water quality, rising emissions, and deteriorating soil stability.

When farmers and researchers began testing the combination of CRU and AWD in this region, the results were striking. Yields increased, nitrogen efficiency improved, emissions dropped sharply, and farmland remained productive without excessive nitrogen inputs. More importantly, this approach offered a glimpse into how future agricultural systems might function—efficient, water-saving, low-emission, and economically viable.

Rethinking Agriculture Through a New Lens

It is now increasingly clear that the future of rice production can no longer rely solely on conventional methods. Ignoring environmental limits ultimately undermines the very foundation of agriculture itself.

The integration of smart fertilizers, water-efficient irrigation, and a deeper understanding of soil ecology opens a more sustainable path forward—one that looks beyond a single harvest toward the wellbeing of future generations.

Across Asia—from China to Southeast Asia—the story of rice farming is gradually shifting toward a more balanced model. It is a long journey toward harmony between human needs and the health of the planet.

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