Scholarlink

<p>Climate warming advances the start of the growing season and enhances carbon uptake on the Qinghai-Tibet Plateau, primarily through the direct effects of air temperature and precipitation. However, the role of spring soil moisture dynamics driven by freeze-thaw processes remains underexplored. Here, using multi-source data from 32 Qinghai-Tibet Plateau sites (2003–2024), we develop a framework to decouple and quantify the moisture-limit relief from freeze-thaw-driven soil moisture return&#xa0;(<i>E</i><sub>SMR</sub>) and concurrent precipitation effect&#xa0;(<i>E</i><sub>prec</sub>). Across study sites, soil moisture return contributes 20.7% ± 2.1% (mean ± SD) of the start of the growing season advance since 2003, surpassing the precipitation effect and air temperature, underscoring the role of pre-freezing moisture return in advancing start of the growing season in the following spring. At sites with active layer thickness exceeding 2.2 m, the <i>E</i><sub>SMR</sub> exhibits ~31% higher sensitivity to surface soil moisture compared to sites with thinner active layer thickness. As active layer thickness deepens, the influence of soil moisture dynamics in the middle and lower active layers, associated with permafrost degradation, may gradually weaken in regulating start of the growing season. Our findings identify freeze-thaw soil moisture dynamics as an important, previously underappreciated control on start of the growing season and spring carbon uptake on the warming Qinghai-Tibet Plateau.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Freeze-thaw-driven soil moisture return significantly contributes to spring phenology on the warming Qinghai-Tibet Plateau

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年4月30日

查看全文
  • Hanrui Zhao,
  • Shouqin Sun,
  • Chunlin Song,
  • Shan Lin,
  • Zhaoyong Hu,
  • Xianhong Meng,
  • Jinlong Li,
  • Linmao Guo,
  • Genxu Wang

摘要

Climate warming advances the start of the growing season and enhances carbon uptake on the Qinghai-Tibet Plateau, primarily through the direct effects of air temperature and precipitation. However, the role of spring soil moisture dynamics driven by freeze-thaw processes remains underexplored. Here, using multi-source data from 32 Qinghai-Tibet Plateau sites (2003–2024), we develop a framework to decouple and quantify the moisture-limit relief from freeze-thaw-driven soil moisture return (ESMR) and concurrent precipitation effect (Eprec). Across study sites, soil moisture return contributes 20.7% ± 2.1% (mean ± SD) of the start of the growing season advance since 2003, surpassing the precipitation effect and air temperature, underscoring the role of pre-freezing moisture return in advancing start of the growing season in the following spring. At sites with active layer thickness exceeding 2.2 m, the ESMR exhibits ~31% higher sensitivity to surface soil moisture compared to sites with thinner active layer thickness. As active layer thickness deepens, the influence of soil moisture dynamics in the middle and lower active layers, associated with permafrost degradation, may gradually weaken in regulating start of the growing season. Our findings identify freeze-thaw soil moisture dynamics as an important, previously underappreciated control on start of the growing season and spring carbon uptake on the warming Qinghai-Tibet Plateau.