摘要
【目的】氧化亚氮是一种痕量温室气体,对全球温室效应起着重要的作用.本文旨在研究稻鸭共作生态系统对氧化亚氮的排放及其温室效应的影响。【方法】在中稻生长季节,运用静态箱技术测定稻鸭共作生态系统氧化亚氮的排放。【结果】在施用等量基肥条件下,与常规稻作相比,稻鸭共作氧化亚氮排放具有不同的日变化和相似的季节变化模式;氧化亚氮日变化与日温度变化基本一致,排放峰值出现在13:00。而氧化亚氮季节变化与温度变化不相关,排放峰值出现在施肥后两周和稻田落干期。较之常规稻作,稻鸭共作生态系统能显著提高氧化亚氮释放。本试验综合评估了稻鸭共作生态系统释放的甲烷和氧化亚氮的综合温室效应。【结论】研究显示,稻鸭共作生态系统能有效抑制甲烷和氧化亚氮的总排放和显著降低甲烷和氧化亚氮的总排放的综合温室效应。因此,在中国南方稻作区,稻鸭共作生态系统是减少甲烷和氧化亚氮的总排放和改善全球气候的措施之一。
[Objective] Nitrous oxide is an important greenhouse gas responsible for global warming. Hence, the main objectives of this study were to evaluate the potential impact of the stocking of duck in paddy fields on N20 emission and to assess GWP of the cultivation system based on their N2O and CH4 emissions. [Method] Nitrous oxide emissions from rice field in subtropical region of China were measured in situ by using static chambers technique during rice growth season in 2006. The experiment field was divided into six plots for two different treatments, and one was conventional rice field （CK） and the other was rice-duck complex ecosystem （RD）. [Result] Under the same urea application as basal fertilizers, compared with CK, the nitrous oxide flux from RD presented distinct daily and similar seasonal variations. Daily variations in nitrous oxide flux were basically consistent with daily temperature variations, and the nitrous oxide emission flux reached a peak at 13：00. But the seasonal variation patterns of nitrous oxide flux were inconsistent with daily temperature variations, and the peak of nitrous oxide flux appeared in 2 weeks after urea application and after drainage of water from the paddy fields. Moreover, RD can significantly increase N2O emission compared with CK. We evaluated the global warming potentials （GWPs） of the methane emission and nitrous oxide in rice-duck complex ecosystem, which showed that rice-duck complex ecosystem could suppress the amount of greenhouse gas from rice paddies and greatly reduced GWPs of CH4 and nitrous oxide emission compared with conventional rice fields. [Conclusion] So, rice-duck complex ecosystem is an effective strategy to reduce greenhouse gas from rice paddies in Southern China, and will contribute to alleviating global warming.
出处
《中国农业科学》
CAS
CSCD
北大核心
2008年第9期2895-2901,共7页
Scientia Agricultura Sinica
基金
国家重大科技专项资助项目(2004BA520A02)
关键词
氧化亚氮
流通量
温室效应
稻鸭共作
Nitrous oxide
Flux
Global warming potential
Rice-duck complex ecosystem
