植物生态学报 ›› 2015, Vol. 39 ›› Issue (3): 249-257.DOI: 10.17521/cjpe.2015.0024

所属专题: 碳水能量通量

• • 上一篇    下一篇

不同施氮水平对冬小麦生长期土壤呼吸的影响

金皖豫, 李铭, 何杨辉, 杜正刚, 邵钧炯, 张国栋, 周灵燕, 周旭辉*()   

  1. 复旦大学教育部生物多样性与生态工程重点实验室, 生物多样性科学研究所, 上海 200433
  • 收稿日期:2014-10-11 接受日期:2015-01-28 出版日期:2015-03-01 发布日期:2015-03-17
  • 通讯作者: 周旭辉
  • 作者简介:

    # 共同第一作者

  • 基金资助:
    国家自然科学基金(31370489和31100352)、上海高校特聘教授(东方学者)岗位计划和中组部青年千人计划

Effects of different levels of nitrogen fertilization on soil respiration during growing season in winter wheat (Triticum aestivum)

JIN Wan-Yu, LI Ming, HE Yang-Hui, DU Zheng-Gang, SHAO Jun-Jiong, ZHANG Guo-Dong, ZHOU Ling-Yan, ZHOU Xu-Hui*()   

  1. Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Institute of Biodiversity Science, Fudan University, Shanghai 200433, China
  • Received:2014-10-11 Accepted:2015-01-28 Online:2015-03-01 Published:2015-03-17
  • Contact: Xu-Hui ZHOU
  • About author:

    # Co-first authors

摘要:

在目前全球氮沉降不断增加的背景下, 研究农田土壤呼吸对氮沉降的响应有助于理解未来生态系统碳循环对全球变暖的潜在影响。为探讨不同施氮浓度对华东地区冬小麦(Triticum aestivum)生长期土壤呼吸的影响, 该实验设计了对照组(不施加氮肥)和3种浓度施氮处理组(低浓度施氮15 g·m-2·a-1, 中等浓度施氮30 g·m-2·a-1, 高浓度施氮45 g·m-2·a-1)。使用便携式土壤CO2通量观测仪LI-8100测定不同施氮浓度处理下冬小麦生长期(2013年12月至2014年5月)的土壤呼吸速率, 并探讨土壤呼吸与土壤温度、湿度等环境因素的关系。结果表明: 低、中、高3种浓度施氮处理的土壤呼吸速率平均值分别为5.29、6.17和6.75 μmol·m-2 ·s-1, 与对照组(土壤呼吸速率平均值为4.90 μmol·m-2·s-1)相比, 分别增加了7.8%、23.6%和37.8%; 地上生物量分别增加39.9%、104.4%和200.2%, 并与冬小麦生长季的总土壤呼吸正相关。5 cm深度土壤的温度与土壤呼吸速率呈指数关系(p < 0.05), 土壤呼吸季节变化的65%-75%由土壤温度引起, 其温度敏感性为2.09-2.32。结果表明, 添加氮肥促进了植物的生长, 增加了生物量, 从而增加了冬小麦农田的土壤呼吸速率。

关键词: 施氮梯度, 冬小麦, 土壤呼吸

Abstract: <i>Aims</i>

Our objective was to explore the effects of different levels of nitrogen (N) fertilization on soil respiration and its temperature sensitivity during growing season in winter wheat (Triticum aestivum) in East China.

<i>Methods</i>

Three levels of N fertilization, N1 (15 g·m-2·a-1), N2 (30 g·m-2·a-1), and N3 (45 g·m-2·a-1), and the control group (CK) were set up in winter wheat fields. The LI-8100 Automated Soil CO2 Flux System was used to measure soil respiration rate during the growing season (December 2013 to May 2014) of winter wheat.

<i>Important findings</i>

During the growing season of winter wheat, mean soil respiration rates of N1, N2 and N3 treatments were 5.29, 6.17 and 6.75 μmol·m-2·s-1, respectively, which were 7.8%, 23.6% and 37.8% greater than that of the CK (4.90 μmol·m-2·s-1). Compared to CK, the N1, N2, and N3 treatments increased the aboveground biomass by 39.9%, 104.4%, and 200.2%, respectively, and the increases were significantly correlated with total soil respiration during the growing season. Soil respiration increased exponentially with soil temperature at the depth of 5 cm, which explained 65%-75% of the variation (p < 0.05). The temperature sensitivity of soil respiration (Q10) calculated based an exponential equation was between 2.09 and 2.32. These results suggested that nitrogen fertilization promoted plant growth, significantly increased biomass of winter wheat, and stimulated the soil respiration.

Key words: N fertilization levels, Triticum aestivum, soil respiration