自然资源学报 ›› 2015, Vol. 30 ›› Issue (10): 1617-1627.doi: 10.11849/zrzyxb.2015.10.002

• 资源生态 • 上一篇    下一篇

河西走廊绿洲玉米农田生态系统呼吸特征及温度响应

陈国鹏1, 2, 赵文智1, 3, *, 吉喜斌3   

  1. 1. 甘肃农业大学 林学院,兰州 730070;
    2. 甘肃省白龙江林业管理局 林业科学研究所,兰州 730070;
    3. 中国科学院 寒区旱区环境与工程研究所 中国生态系统研究网络临泽内陆河流域研究站/中国科学院 内陆河流域生态水文重点实验室,兰州 730000
  • 收稿日期:2014-10-15 修回日期:2015-04-16 出版日期:2015-10-15 发布日期:2015-10-15
  • 通讯作者: *通信作者,E-mail: zhaowzh@lzb.ac.cn
  • 作者简介:陈国鹏(1986- ),男,博士,研究方向为生态系统碳水循环。E-mail: chgp1986@gmail.com
  • 基金资助:
    国家杰出青年科学基金(41125002)

Ecosystem Respiration of Maize Agroecosystem and Its Response to Temperature in the Hexi Corridor, China

CHEN Guo-peng1, 2, ZHAO Wen-zhi1, 3, JI Xi-bin3   

  1. 1. College of Forestry, Gansu Agricultural University, Lanzhou 730070, China;
    2. Institute of Forestry Sciences, Bailongjiang Forestry Management Bureau of Gansu Province, Lanzhou 730070, China;
    3. Linze Inland River Basin Research Station/ Key Laboratory Inland River Ecohydrology, Cold and Arid Regions Environmental and Engineering Research Institute, CAS, Lanzhou 730000, China
  • Received:2014-10-15 Revised:2015-04-16 Online:2015-10-15 Published:2015-10-15

摘要: 准确评估农田生态系统碳排放对评价陆地生态系统碳平衡具有重要意义。研究利用中国生态系统研究网络临泽内陆河流域研究站玉米农田生态系统涡度相关和微气象监测数据,分析了2009年生态呼吸速率(RE)和呼吸敏感性指数(Q10)的季节变化规律,探讨了环境因子对RE的影响,比较了不同模型估算生态系统碳排放量的差异。结果表明,河西走廊荒漠绿洲玉米农田生态系统夜间平均呼吸速率表现为单峰型的季节动态,平均最大呼吸速率12.54 μmol CO2·m-2·s-1;空气温度(Ta)比土壤温度(Ts)更明显地影响着玉米农田生态系统呼吸,且影响过程表现出明显的季节差异;基于Q10模型拟合的4—10月各月的参考呼吸速率RE10和敏感性指数Q10也表现出单峰型的季节变化模式,最大值先后出现在6月和8月,其值分别为2.68 μmol CO2·m-2·s-1和2.62。Logistic模型能较好地反映RETa的关系,可以解释半小时呼吸速率55.9%的变异,但在高温情况下的预测值偏低;Q10、Quadratic、Lloyd & Taylor和Logistic模型模拟的玉米农田生态系统呼吸速率的平均日变化和季节动态差异明显,估算的河西走廊荒漠绿洲玉米农田生态系统年呼吸碳排放量介于1 122~1 252 g C·m-2·a-1

Abstract: The ecosystem respiration (RE), following gross primary productivity, is the second largest carbon flux in global carbon cycle. CO2 flux was measured continuously using the eddy covariance technique in a maize agroecosystem at middle reaches of Heihe River in northwest China. The seasonal variation of ecosystem respiration and the temperature controls on them were investigated. The results show that the mean ecosystem respiration at night (REmean) of maize agroecosystem shows a topical single peak, the highest values of REmean being 12.54 μmol·m-2·s-1 which is observed in July. RE at 2 m height increased exponentially with air temperature (Ta) better than with soil temperature (Ts). The rate of basal ecosystem respiration (RE10) and the calculated temperature sensitivity for ecosystem respiration (Q10) from April to October showed single peak, the highest values of RE10 and Q10 being 2.68 μmol·m-2·s-1 in June and 2.62 in August, respectively. A Logistic model fit best to the relationship between half hours RE and air temperature, explaining 55.9% of the variation in RE over the annual cycle, but the performance of the model was poor during period of high Ta. The annual total of RE of the maize agroecosystem in the Hexi Corridor in 2009 were form 1122 to 1252 g C·m-2·a-1 estimated by Q10, Quadratic, Lloyd & Taylor and Logistic models.

中图分类号: 

  • Q148