土壤碳氮特征沿干旱梯度时空格局及对气候变化的响应——基于中国生态系统研究网络(CERN)长期定位监测数据

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 土壤碳氮特征沿干旱梯度时空格局及对气候变化的响应——基于中国生态系统研究网络(CERN)长期定位监测数据 DOI: 10.5846/stxb202205311527 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 中国科学院国际合作局对外合作重点项目(121311KYSB20170004);中国科学院战略性先导科技专项(XDA19020305);中国博士后科学基金面上资助项目(2020M670439) Spatio-temporal patterns of soil carbon and nitrogen characteristics along aridity gradients and their responses to climate change: Based on long-term field observation data of Chinese Ecosystem Research Network Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:土壤碳氮含量及其化学计量特征是表征生态系统碳汇能力和土壤质量的重要指标,在支撑生态系统结构功能以及缓解气候变化中起着关键作用。利用中国生态系统研究网络(CERN)长期定位监测数据,分析了土壤碳氮特征沿干旱梯度的时空规律及其对气候变化的响应。结果表明:空间上,典型荒漠草原生态系统随着干旱加剧,土壤有机碳和全氮含量减少,土壤有机碳对干旱响应的敏感性降低,而土壤全氮对干旱响应的敏感性增加,土壤有机碳随土壤全氮含量的增加而增加。时间上,2005-2018年,荒漠草原生态系统土壤有机碳和全氮含量变化速率沿干旱梯度表现出由负转正的增加趋势,其中,干旱区呈减少趋势,半干旱和半湿润地区呈增加趋势,鄂尔多斯站和沙坡头站呈显著增加趋势。从影响因素来看,土壤碳氮特征对降水量增加的敏感性沿干旱梯度呈现出先增强后减弱的"上凸"抛物线趋势,温度变化对土壤碳氮特征的调控没有表现出明显的干旱梯度效应。土壤碳氮比、土壤有机碳含量、土壤全氮含量对降水量和平均温度变化响应的敏感性均依次降低。不同干旱梯度土壤碳氮特征的变化规律为未来气候变化下生态系统结构与功能预测提供科学依据。 Abstract:Soil organic carbon content (SOC), soil total nitrogen content (TN) and its ecological stoichiometric characteristics indicate the carbon sink efficiency and soil quality of ecosystem, and play the critical role in supporting ecosystem structure and function and mitigating climate change. Using long-term field observation data of ecological stations of the Chinese Ecosystem Research Network (CERN), this study analyzed the spatio-temporal patterns of the SOC, TN and its stoichiometric characteristics of soil, and their responses to climate change along aridity gradient. Results showed that with the aridity intensifying spatially, the SOC and TN decreased, the response sensitivity of SOC to aridity decreased and that of the TN increased. The SOC was increased along the TN increasing. Temporally, the rate of SOC and TN changes with aridity gradient showed increased with the aridity mitigating, which were negative in the aridity region and positive in semi-arid region from 2005 to 2018. The SOC and TN of Shapotou station and Erdos station were significant increased with aridity change in past more than one decade. Additionally, the response sensitivity of the SOC, TN and stoichiometric characteristics to precipitation increasing showed an "upwardly convex" pattern, which firstly increased and then decreased with the aridity gradient, but none for temperature. The response sensitivity of the SOC, TN and carbon-nitrogen ratio to changes in precipitation and temperature were as follows: the sensitivity of soil carbon-nitrogen ratio > the sensitivity of SOC > the sensitivity of TN. It is implied that the rule of the SOC, TN and its ecological stoichiometric characteristics changes in different aridity gradient region provide the scientific basis for the of ecosystem structure and function prediction under future climate change. 参考文献 相似文献 引证文献