Effects of climate warming on debris flow activity and sediment supply in high mountain regions.

气候变暖对高山地区泥石流活动和泥沙供应的影响.

• 批准号: 399435624
• 负责人: Professor Dr. Bodo Bookhagen, Ph.D., since 10/2023
• 金额: --
• 依托单位: Institut für Geowissenschaften
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/399435624?language=en
• 关键词: Effects; climate; warming; debris; flow

In the framework of the paraglacial cycle (i.e., the theoretical model that describes the sediment flux evolution after deglaciation), this project wants to analyze the effects that the ongoing climate warming has on the sediment supply and on the occurrence of debris-flow events in mountain catchments. Previous studies on these topics indicate that climate plays a crucial role in the surface processes dynamics and sediment transfer in mountain basins. However, the different response of mountain catchments to the modern climate-change suggests that some other parameter, in addition to the increase in water discharge and sediment availability that follows the melting of ice, may control the dynamics of sediment production and sediment transfer. Recent studies have suggested that a good connectivity and a balanced transport capacity of the rivers may be pivotal in this context. However, studies that investigate these aspects within the sediment cascade of mountain basins and in light of climate warming remain scarce. In this project, I propose to analyze two small valleys of the Italian Alps in the effort to understand the response of mountain catchments to climate warming and assess the role that glacial melting, permafrost degradation, and increased extreme precipitation may have on sediment supply and debris-flow activity. To reach these goals, I propose to combine different techniques and analyze: 1) the variations in the sediment transport dynamics of mountain basins by means of cosmogenic nuclides techniques; 2) the chronology of debris-flow events through dendrochronology dating; and 3) the location of debris flows and rock falls initiation areas by the time-series analysis of orthophotos. By analyzing basins with different morphologies, I will be able to frame the effects of local parameters (such as morphology, vegetation, and connectivity) in the sediment transport dynamics of mountain catchments. This approach will allow me to explore the effect of temperature and extreme precipitation increase on both glaciated and deglaciated basins, and to assess their influence on the release and transport of sediment. By combining these different techniques I will cover different timescales, integrating existing information (i.e., database of natural hazard events) with new data on the past, and using them to explore possible future scenarios. The project outcomes are expected to bring us one step forward in the understanding of how climate may modulate surface processes in mountain catchments. The relevance of these results is not limited to the scientific community, but is expected to be of primary importance also for local and regional authorities, who may use the project’s outcomes to reduce the vulnerability of mountain regions and develop sustainable management plans for Alpine environments.

在副冰旋回的框架内（即，该项目旨在分析持续的气候变暖对沉积物供应和山区流域泥石流事件发生的影响。以往的研究表明，气候在山区盆地的地表过程、动力学和沉积物迁移中起着至关重要的作用。然而，不同的山区集水区对现代气候变化的反应表明，一些其他参数，除了增加水流量和沉积物的可用性，以下冰融化，可能会控制泥沙生产和泥沙转移的动态。最近的研究表明，在这方面，河流的良好连通性和平衡的运输能力可能至关重要。然而，在山区盆地的沉积物级联中并根据气候变暖调查这些方面的研究仍然很少。在这个项目中，我建议分析意大利阿尔卑斯山的两个小山谷，以了解山区流域对气候变暖的反应，并评估冰川融化，永久冻土退化和极端降水增加可能对沉积物供应和泥石流活动的作用。为此，我建议联合收割机结合不同的技术，分析：1）通过宇宙成因核素技术分析山区盆地的泥沙输运动力学变化; 2）通过树木年代学测年分析泥石流事件的年代学; 3）通过正射影像的时间序列分析来确定泥石流和罗克瀑布起始区的位置。通过分析具有不同形态的盆地，我将能够框的局部参数（如形态，植被和连通性）在山区集水区的泥沙输运动力学的影响。这种方法将使我能够探索温度和极端降水增加对冰川和冰川消退盆地的影响，并评估它们对沉积物释放和运输的影响。通过结合这些不同的技术，我将涵盖不同的时间尺度，整合现有的信息（即，自然灾害事件数据库）与过去的新数据，并利用它们来探讨未来可能出现的情况。预计该项目的成果将使我们在了解气候如何调节山区集水区的地表过程方面向前迈出一步。这些成果的相关性不仅限于科学界，而且预计对地方和区域当局也具有首要重要性，它们可以利用该项目的成果来减少山区的脆弱性，并为阿尔卑斯山环境制定可持续管理计划。