Nitrogen Use Efficiency, Crop Productivityand Environmental Impacts of Urea Deep

Placement in Lowland Rice Fields

Yam GaihreSoil ScientistInternational Fertilizer Development Center (IFDC)Bangladesh

Urea Deep Placement (UDP) in Lowland Rice Fields

• Nitrogen recovery (REN): 30 –50%

• Losses to the environment—Leaching, Surface runoff,ammonia volatilization, N2Oand NO emissions

• Increase RE from 30-50 % to70-75%

• Increase in grain yield up to20% while saving 30% ureafertilizer

Urea Briquette NPK Briquette

Broadcast method Deep placement

UDP: More Grains with Less UreaReduces NH4 in Floodwaterand NH3 Volatilization

Increases Yields and NUE

UDP increased grain yields by 21%compared to broadcast PU.

Doubled the NUE over broadcast PU(35 %vs 70%)0

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Control UDP Broadcast PU

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2014 (CSW) 2015 (AWD)

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Control Broadcast PU UDP

UDP Reduces GHG N2O and NO emissions Reduced emissions by up to 80%

as compared to broadcast PUunder continuous standing water(CSW) management regime.

The effects of UDP under the AWDwater management regime weresite specific depending on theduration and intensity of soil drying.

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2014 (CSW) 2015 (AWD)

N2O

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Control Broadcast PU UDP

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2014 (CSW) 2015 (AWD)

N2O

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Control Broadcast PU UDP

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