Biogeochemistry of N₂O Uptake and Consumption in Submerged Soils and Rice Fields and Implications in Climate Change

Abstract

Submerged soils and rice fields are known sources of nitrous oxide (N₂O) but also act as its sinks. Nitrous oxide uptake (movement from atmosphere into soil) and consumption (conversion of N₂O to N₂) in rice fields are both very significant, as they help decrease N₂O concentration in the atmosphere. Rice soils had reportedly shown N₂O uptake ranging from about 0.13 to 191 μg N₂O-N m⁻² hr⁻¹ while in non-rice soils the same was about 0.0014–484 μg N₂O-N m⁻² hr⁻¹. This review synthesizes the available information on N₂O uptake and consumption in submerged soils vis-à-vis rice fields.

KEY WORDS:

• denitrification
• flooded soil
• global warming
• nitrification
• paddy
• reduction
• sink

ACKNOWLEDGMENT

The author thanks the Head of Air Pollution Control Division and Director, NEERI, for their constant encouragement and guidance.