Effect of soil water status and mulching on N 2 O and CH 4 emission from lowland rice field in China

• DOI: 10.1007/s00374-003-0692-4
• Publication Date: 2004-02-20T06:57:08Z
• Authors: Y. C. Xu; Q. R. Shen; M. L. Li; K. Dittert; B. Sattelmacher
• Keywords: 2. Zero hunger; 13. Climate action; 0401 agriculture, forestry, and fisheries; 04 agricultural and veterinary sciences; 15. Life on land; 6. Clean water; 12. Responsible consumption

Cultivation of rice in unsaturated soils covered with mulch is receiving more attention in China because of increasingly serious water shortage; however, greenhouse gas emission from this cultivation system is still poorly understood. A field experiment was conducted in 2001 to compare nitrous oxide (N2O) and methane (CH4) emission from rice cultivated in unsaturated soil covered with plastic or straw mulch and the traditional waterlogged production system. Trace gas fluxes from the soil were measured weekly throughout the entire growth period using a closed chamber method. Nitrous oxide emissions from unsaturated rice fields were large and varied considerably during the rice season. They were significantly affected by N fertilizer application rate. In contrast, N2O emission from the waterlogged system was very low with a maximum of 0.28 mg N2O m−2 h−1. However, CH4 emission from the waterlogged system was significantly higher than from the unsaturated system, with a maximum emission rate of 5.01 mg CH4 m−2 h−1. Our results suggested that unsaturated rice cultivation with straw mulch reduce greenhouse gas emissions.