资源与生态学报 ›› 2012, Vol. 3 ›› Issue (1): 93-96.DOI: 10.5814/j.issn.1674-764x.2012.01.014

• 专题报告 • 上一篇    

东日本自然湿地的土壤反硝化

张秋英1,3, 李发东2, 唐常源3   

  1. 1. 中国科学院遗传与发育生物学研究所 农业资源中心, 石家庄 050021;
    2. 中国科学院地理科学与资源研究所 生态网络观测与模拟重点实验室, 北京 100101;
    3. 日本千叶大学, 日本千叶 271-8510
  • 收稿日期:2012-02-05 修回日期:2012-03-01 出版日期:2012-03-30 发布日期:2012-03-30
  • 通讯作者: ZHANG Qiuying. Email: qiuying.zhang@gmail.com.

Quantifying of Soil Denitrification Potential in a Wetland Ecosystem, Ochi Experiment Site, Japan

ZHANG Qiuying1,3, LI Fadong2, TANG Changyuan3   

  1. 1. Key Laboratory of Agricultural Water Resources, Centre for Agricultural Resources Research, Institute of Genetic and Developmental Biology, CAS, Shijiazhuang 050021, China;
    2. Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China;
    3. Faculty of Horticulture, Chiba University, Chiba 271-8510, Japan
  • Received:2012-02-05 Revised:2012-03-01 Online:2012-03-30 Published:2012-03-30
  • Supported by:

    This study was supported by the 100-Talent Project, Chinese Academy of Sciences and the Grant-in-Aid for Scientific Research of Japan Society for the Promotion of Science (No. 19310004).

摘要: 地表水和地下水中硝酸盐污染已成为重要的环境问题之一。随着对全球变暖的贡献增加,N2O(氧化亚氮)也得到IPCC越来越多的关注。反硝化在水生生态系统氮循环过程中起着极为重要的作用。反硝化过程中,厌氧细菌将硝酸盐转化成可溶性亚硝酸盐,最终以N2形式排放到大气。为理解自然湿地生态系统的脱氮机理,以日本千叶县的越智小流域为例开展研究。沿地下水流动方向取原状土,包括2个非饱和带点和2个饱和带点。用乙炔抑制法和带ECD检测器的气相色谱仪于0, 2, 6,12, 24h测定土壤反硝化能力。同时分析土壤全碳、全氮和反硝化细菌。结果发现,饱和带的反硝化能力高于非饱和带。乙炔抑制后,N2O排放从0-1.17 g Nm-2h-1,前6h增至最大,随后降低。

关键词: 反硝化, N2O排放, 天然湿地

Abstract: Nitrate contamination has become one of the most important issues for surface water and groundwater. N2O, with an increasing contribution to global warming, has been more and more attention by the IPCC recently. As well known, denitrification plays a major role in nitrogen cycle of aquatic ecosystems and operates at rates far below its potential under proper conditions. Sediments are the single largest pool of nitrogen in wetland ecosystems. During this process, facultative anaerobic bacteria transform nitrite into nitrogen gas which dissolves in the groundwater and diffuses into the atmosphere finally when it shows up with seepage or spring in the wetland. To seek a mechanistic understanding of N removal in natural wetland ecosystem, a case study was carried in terms of denitrification rate at the Ochi catchment, Chiba, Japan. In this study, samples of intact soil cores in 0–20cm were taken along the groundwater flow path, which including 2 samples in the unsaturated zone and 2 in saturated wetland ecosystem. Denitrification capacity of soil was quantified using acetylene (C2H2) inhibition/gas chromatography ECD method with time intervals of 0, 2, 6, 12, 24 h. Total-N and Total-C contents and amount of denitrifying bacteria were also analyzed. It is found that denitrification ability is low for all 2 samples in the unsaturated zone and high in saturated zone. Results show that N2O emission flux after C2H2-inhibition ranges from 0 to 1.17 gN m-2h-1, with an increase value prior 6 hours and slow down after that.

Key words: denitrification, N2O emission, natural wetland