Han Juanjuan, Tan Chaowei, Ru Jingyi, Song Jian, Hui Dafeng, Wan Shiqiang
Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station, School of Geographical Sciences, Southwest University, Chongqing, China.
School of Life Sciences, Hebei University, Baoding, China.
Nat Commun. 2025 May 13;16(1):4431. doi: 10.1038/s41467-025-59761-8.
Frosts, increasingly prevalent due to climate warming, can offset the carbon storage benefits of an extended growing season, potentially exacerbating climate warming. However, existing research primarily focus on species, with limited evidence on carbon fluxes at the ecosystem scale. Using a manipulative experiment simulating 7-day frosts in a temperate grassland, we find that ongoing frosts, whether in spring or autumn, have limited effects on gross ecosystem productivity, ecosystem respiration, and net ecosystem productivity during the frost measurement periods. However, frosts profoundly impact net ecosystem productivity over the entire growing season outside the frost measurement periods. Specifically, spring frosts significantly increase net ecosystem productivity, autumn frosts marginal decrease it, and the combined effect of both frosts neutralize net ecosystem productivity. The early-year (2018-2020) impacts of frosts on net ecosystem productivity may be driven by plant eco-physiological changes, whereas the late-year impacts (2021-2023) were attributed to shifts in plant community structure. Our findings suggest that frequent frosts in both seasons may not stimulate ecosystem carbon release in temperate grasslands. Understanding these patterns is crucial for predicting carbon balance and developing effective climate-change mitigation strategies in response to the future warmer climate.
由于气候变暖，霜冻日益普遍，这可能抵消生长季延长带来的碳储存益处，从而可能加剧气候变暖。然而，现有研究主要集中在物种层面，关于生态系统尺度碳通量的证据有限。通过在温带草原进行模拟为期7天霜冻的控制实验，我们发现，无论是春季还是秋季，正在发生的霜冻在霜冻测量期间对生态系统总生产力、生态系统呼吸和生态系统净生产力的影响有限。然而，霜冻在霜冻测量期之外的整个生长季对生态系统净生产力有深远影响。具体而言，春季霜冻显著提高生态系统净生产力，秋季霜冻使其略有下降，两种霜冻的综合作用使生态系统净生产力抵消。霜冻对生态系统净生产力的早年（2018 - 2020年）影响可能由植物生态生理变化驱动，而晚年（2021 - 2023年）影响则归因于植物群落结构的变化。我们的研究结果表明，两个季节频繁出现的霜冻可能不会刺激温带草原生态系统的碳释放。了解这些模式对于预测碳平衡以及制定应对未来气候变暖的有效气候变化缓解策略至关重要。
