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生态学杂志 ›› 2024, Vol. 43 ›› Issue (1): 41-49.doi: 10.13292/j.1000-4890.202401.035

• 高寒草甸草原退化机理与生态修复专栏 • 上一篇    下一篇

高寒草甸土壤呼吸及其组分对氮添加的响应

史嘉炜,廖家强,魏春雪,彭逸飞,李婷婷,胡健,汪金松,周青平*   

  1. 1西南民族大学四川若尔盖高寒湿地生态系统国家野外科学观测研究站, 成都 610041; 2中国科学院地理科学与资源研究所生态系统网络观测与模拟重点实验室, 北京 100101; 3河北农业大学资源与环境科学学院, 河北保定 071000)

  • 出版日期:2024-01-10 发布日期:2024-01-08

Responses of soil respiration and its components to nitrogen addition in an alpine meadow.

SHI Jiawei, LIAO Jiaqiang, WEI Chunxue, PENG Yifei, LI Tingting, HU Jian, WANG Jinsong, ZHOU Qingping*   

  1. (1Sichuan Zoige Alpine Wetland Ecosystem National Observation and Research Station, Southwest Minzu University, Chengdu 610041, China; 2Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; 3School of Resources and Environmental Sciences, Hebei Agricultural University, Baoding 071000, China).

  • Online:2024-01-10 Published:2024-01-08

摘要: 本研究比较了青藏高原高寒草甸土壤呼吸速率(Rs)、自养呼吸速率(Ra)和异养呼吸速率(Rh)随施氮梯度的变化,揭示土壤呼吸及其组分变化的主要影响因素,为评价未来氮沉降背景下高寒草甸土壤碳释放提供科学依据。于2014年在四川红原青藏高原高寒草甸建立长期氮素添加平台,采取完全随机区组试验设计,设置0(N0,对照)、2(N2)、4(N4)、8(N8)、16(N16)和32 g N·m-2·a-1(N32)6个水平氮素添加控制实验。于2020年生长季对Rs、Ra和Rh进行监测。结果表明:施氮显著降低了土壤呼吸及其组分(P<0.05),且Ra的下降幅度大于Rh,导致Rh/Rs随施氮水平逐渐上升;不同施氮处理下Ra和Rh与土壤温度均呈显著的指数正相关(P<0.05);施氮降低了Ra的温度敏感性(Q10),但提高了Rh的Q10值;土壤呼吸各组分与土壤湿度的关系均不显著,但土壤温度和土壤湿度双因子模型对Ra和Rh的解释度高于单因素模型。本研究揭示了高寒草甸土壤呼吸及其组分对氮添加的响应特征及机制,可为评估高寒草甸生态系统对大气氮沉降的响应以及生态系统管理提供科学依据。


关键词: 高寒草甸, 土壤呼吸, 自养呼吸, 异养呼吸, 温度敏感性

Abstract: This study aimed to compare the changes of soil respiration rate (Rs), autotrophic respiration rate (Ra), and heterotrophic respiration rate (Rh) across a nitrogen application gradient in an alpine meadow on the Qinghai-Tibet Plateau, reveal the main influencing factors of soil respiration and its components, and provide a scientific basis for evaluating soil carbon release from alpine meadows under future nitrogen deposition. In 2014, a nitrogen addition platform was established in the alpine meadow of the Qinghai-Tibet Plateau in Hongyuan, Sichuan, following a completely randomized block experimental design with six levels of nitrogen addition, including 0 (N0, control), 2 (N2), 4 (N4), 8 (N8), 16 (N16) and 32 (N32) g N·m-2·a-1. Nitrogen application significantly decreased soil respiration and its components (P<0.05), and Ra decreased more than Rh, resulting in a gradual increase of Rh/Rs with the nitrogen addition gradient. There were significant exponential positive correlations between Ra and Rh and soil temperature under different nitrogen addition treatments (P<0.05). Nitrogen addition decreased the temperature sensitivity (Q10) of Ra, but increased that of Rh. The relationship between the components of soil respiration and soil moisture was not significant, but the two-factor model of soil temperature and soil moisture explained Ra and Rh better than the single-factor model. Our results enhance mechanistic understanding of soil respiration and its components in response to nitrogen addition in an alpine meadow, and provide a theoretical basis for evaluating the response of alpine meadow ecosystems to atmospheric nitrogen deposition and guiding ecosystem management.


Key words: alpine meadow, soil respiration, autotrophic respiration, heterotrophic respiration, temperature sensitivity