植物生态学报 ›› 2019, Vol. 43 ›› Issue (2): 165-173.DOI: 10.17521/cjpe.2018.0267

所属专题: 碳水能量通量

• 研究论文 • 上一篇    下一篇

氮磷添加对昆仑山北坡高山草地N2O排放的影响

曹登超1,2,3,4,高霄鹏1,2,3,*(),李磊1,2,3,桂东伟1,2,3,曾凡江1,2,3,匡文浓1,2,3,4,尹明远1,2,3,4,李言言1,2,3,4,艾力•甫拉提5   

  1. 1 中国科学院新疆生态与地理研究所荒漠与绿洲生态国家重点实验室, 乌鲁木齐 830011
    2 新疆策勒荒漠草地生态系统国家野外科学观测研究站, 新疆策勒 848300
    3 中国科学院干旱区生物地理与生物资源重点实验室, 乌鲁木齐 830011
    4 中国科学院大学, 北京 100049
    5 新疆策勒县草原工作站, 新疆策勒 848300
  • 收稿日期:2018-10-30 接受日期:2019-02-01 出版日期:2019-02-20 发布日期:2019-06-04
  • 通讯作者: 高霄鹏
  • 基金资助:
    国家自然科学基金(31570002);国家自然科学基金(31870499)

Effects of nitrogen and phosphorus additions on nitrous oxide emissions from alpine grassland in the northern slope of Kunlun Mountains, China

CAO Deng-Chao1,2,3,4,GAO Xiao-Peng1,2,3,*(),LI Lei1,2,3,GUI Dong-Wei1,2,3,ZENG Fan-Jiang1,2,3,KUANG Wen-Nong1,2,3,4,YIN Ming-Yuan1,2,3,4,LI Yan-Yan1,2,3,4,Aili PULATI5   

  1. 1 Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, ürümqi 830011, China
    2 Cele National Station of Observation and Research for Desert-Grassland Ecosystems in Xinjiang, Cele, Xinjiang 848300, China
    3 Key Laboratory of Biogeography and Bio-resource in Arid Zone, Chinese Academy of Sciences, ürümqi 830011, China
    4 University of Chinese Academy of Sciences, Beijing 100049, China
    5 Cele Grassland Management Station in Xinjiang, Cele, Xinjiang 848300, China
  • Received:2018-10-30 Accepted:2019-02-01 Online:2019-02-20 Published:2019-06-04
  • Contact: GAO Xiao-Peng
  • Supported by:
    Supported by the National Natural Science Foundation of China(31570002);Supported by the National Natural Science Foundation of China(31870499)

摘要:

氮(N)、磷(P)等养分添加是提高草地生态系统生产力的重要策略, 但其对土壤氧化亚氮(N2O)排放的影响尚不明确。该研究以南疆昆仑山北坡高山草地为研究对象, 设置氮添加、磷添加、氮磷交互以及不施肥(CK) 4个处理, 采用静态箱-气象色谱法连续监测2017年生长季草地的N2O排放, 研究不同氮、磷添加处理下的N2O排放特征, 并利用Pearson相关分析对影响N2O排放的主要环境因子进行定性识别及定量解析。结果表明: 氮添加处理与氮磷交互处理在施肥后约3周引起显著的N2O排放峰, 分别为42.3和15.4 g N·hm -2·d -1。与其他处理相比, 氮添加处理生长季N2O排放通量显著增加了1.8-3.2倍, 而磷添加以及氮磷交互处理与CK之间没有显著差异。Pearson相关分析结果表明: N2O排放与微生物生物量碳呈负相关关系, 与溶解性有机碳含量、pH值呈正相关关系, 而与其他环境因子关系不显著。以上结果表明, 与单施氮肥相比, 在该地区草场采用氮磷混施可显著减少N2O的排放。

关键词: 高山草地, 氮磷添加, 氧化亚氮, 昆仑山, 通量特征

Abstract: <i>Aims</i>

Nutrient additions such as nitrogen and phosphorus are important strategies to improve the productivity of the grassland ecosystem. However, their effect on soil nitrous oxide (N2O) emissions remains unclear.

<i>Methods</i>

A field study was conducted in an alpine grassland located in the north slope of Kunlun Mountains in Southern Xinjiang. Four treatments included nitrogen addition alone (N), phosphorus addition alone (P), mixture of nitrogen and phosphorus additions (N + P) and an unfertilized control (CK). Gas samples were collected and analyzed using the static chamber chromatography methodology during the 2017 growing season. Treatment effects on the characteristics of N2O emissions from grassland soil were thoroughly investigated. Pearson correlation analysis was used to identify and quantify the influence of environmental variables on soil N2O emissions.

<i>Important findings</i>

The results showed that N and (N + P) treatments induced N2O flux peaks after three weeks of fertilizer addition, with the maximum daily N2O flux rates of 42.3 and 15.4 g N·hm -2·d -1, respectively. The N treatment significantly increased growing season cumulative N2O emissions by 1.8 to 3.2 times compared to P treatment, (N + P) treatment and CK, and there were no significant differences between the three treatments. Pearson correlation analysis showed that daily N2O flux rate was correlated negatively with soil microbial biomass carbon, and positively with soil pH and dissolved organic carbon. There was no significant correlation between daily N2O flux rate and other environmental variables. These results suggest that simultaneous addition of nitrogen and phosphorus nutrients can significantly reduce soil N2O emission compared to N treatment for the alpine grassland in this region.

Key words: alpine grassland, nitrogen and phosphorus addition, N2O, Kunlun Mountains, flux characteristic