The use of dendrochronology to study and date geomorphic processes in volcanic environments is still incipient, even more so on the volcanic slopes covered by temperate forests in central Mexico. Mass movements, such ...The use of dendrochronology to study and date geomorphic processes in volcanic environments is still incipient, even more so on the volcanic slopes covered by temperate forests in central Mexico. Mass movements, such as debris flows, often impact forest stands where they cause damage to individual trees, thereby generating growth disturbances(GD) in the tree-ring records. The identification and dating of GD enables reconstruction of the age of trees colonizing bare surfaces after major events, but also allows the assessment of the frequency or spatial distribution of past geomorphic process activity. Here we used increment cores from 65 Pinus leiophylla, Abies religiosa, and Alnus jorullensis trees growing in the Axal gorge, on the southern slopes of La Malinche volcano, to unravel past debris-flow activity both temporally and spatially. Based on the combination of GD records, a weighted tree response index(Wit), field evidence and hydrometeorological records, we reconstructed 23 debris flows since 1933.Interestingly, almost two-thirds of the reconstructed years with debris-flow activity in Axal gorge match with events recorded in Axaltzintle gorge located on the NE slopes of La Malinche. These findings suggest a regional triggering mechanism, most likely related to the occurrence of hurricanes. This research could be useful for disaster risk management of the La Malinche National Park.展开更多
青藏高原及其周边区域通常被称为地球“第三极”.它不仅是受全球气候变暖影响最显著的区域之一,同时也是全球冰湖溃决洪水(Glacial Lake Outburst Floods,GLOFs)灾害频发的地区之一.尽管之前已经有很多发生在第三极地区的GLOF事件被报道...青藏高原及其周边区域通常被称为地球“第三极”.它不仅是受全球气候变暖影响最显著的区域之一,同时也是全球冰湖溃决洪水(Glacial Lake Outburst Floods,GLOFs)灾害频发的地区之一.尽管之前已经有很多发生在第三极地区的GLOF事件被报道,但考虑到GLOFs通常发生在高海拔无人区以及一些小规模的GLOFs并没有对下游地区造成太大的破坏,可能仍然有一些已经发生的GLOF事件并没有被发现和报道.基于此假设,本文借助大量高分辨率的卫星影像和3个GLOF发生后遗留的典型地貌形态特征对整个第三极地区6万多个冰湖进行了全面和系统地检查,最终识别出176个之前没有被记录的GLOF源头,其中167个来自冰碛坝湖,9个来自基岩坝湖.这一数量是所有已报道GLOF源头数量(75个)的2倍多.综合这些新发现的和已报道的GLOF案例,本文总结出第三极地区GLOF高发的4个热点地区为:喜马拉雅、冈底斯山、念青唐古拉山和天山地区.这些新识别的GLOF案例将为未来的研究提供重要的基础,从而有助于更好地认识和理解第三极地区GLOF的发生机理及真实的发生频率.展开更多
文摘The use of dendrochronology to study and date geomorphic processes in volcanic environments is still incipient, even more so on the volcanic slopes covered by temperate forests in central Mexico. Mass movements, such as debris flows, often impact forest stands where they cause damage to individual trees, thereby generating growth disturbances(GD) in the tree-ring records. The identification and dating of GD enables reconstruction of the age of trees colonizing bare surfaces after major events, but also allows the assessment of the frequency or spatial distribution of past geomorphic process activity. Here we used increment cores from 65 Pinus leiophylla, Abies religiosa, and Alnus jorullensis trees growing in the Axal gorge, on the southern slopes of La Malinche volcano, to unravel past debris-flow activity both temporally and spatially. Based on the combination of GD records, a weighted tree response index(Wit), field evidence and hydrometeorological records, we reconstructed 23 debris flows since 1933.Interestingly, almost two-thirds of the reconstructed years with debris-flow activity in Axal gorge match with events recorded in Axaltzintle gorge located on the NE slopes of La Malinche. These findings suggest a regional triggering mechanism, most likely related to the occurrence of hurricanes. This research could be useful for disaster risk management of the La Malinche National Park.
基金funding from the ERC Advanced Project MONOSTAR (Ad G 882727)funding from Sust ES: adaptation strategies for sustainable ecosystem services and food security under adverse environmental conditions (CZ.02.1.01/0.0/0.0/16_0 19/0000797)+11 种基金funding from the Fritz & Elisabeth Schweingruber Foundation. Duncan A. Christie and Carlos Le Quesne received funding from the ANID (FONDECYT 1201411, 1221307, FONDAP 15110009, BASAL FB210018)funding from the Russian Science Foundation grant (RSF 21-17-00006)funding from NSF Arctic Social Science 2112314NSF Arctic Natural Science 2124885the NSF P2C2 (Paleo Perspectives on Climatic Change) program (various grants)funding from the Russian Science Foundation grant (RSF 21-1400330)funding from the Russian Science Foundation grant (RSF 18-14-00072P)supported by the Swedish Research Council (201801272)funding from the Swiss National Science Foundation through the SNSF Sinergia CALDERA project (CRSII5 183571)funding from the National Science Foundation’s P2C2 Program (1902625 and 1203749)the Malcolm H.Wiener Foundationfunded through NSF P2C2 Program (2002454)
基金This work was supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDA19030301,XDA20030101)A special acknowledgment is to China-Pakistan Joint Research Center on Earth Sciences that supported the implementation of this study.Guoxiong Zheng thanks the China Scholarship Council for supporting his visit to the University of Geneva from February 2019 to February 2021(201804910569).
文摘青藏高原及其周边区域通常被称为地球“第三极”.它不仅是受全球气候变暖影响最显著的区域之一,同时也是全球冰湖溃决洪水(Glacial Lake Outburst Floods,GLOFs)灾害频发的地区之一.尽管之前已经有很多发生在第三极地区的GLOF事件被报道,但考虑到GLOFs通常发生在高海拔无人区以及一些小规模的GLOFs并没有对下游地区造成太大的破坏,可能仍然有一些已经发生的GLOF事件并没有被发现和报道.基于此假设,本文借助大量高分辨率的卫星影像和3个GLOF发生后遗留的典型地貌形态特征对整个第三极地区6万多个冰湖进行了全面和系统地检查,最终识别出176个之前没有被记录的GLOF源头,其中167个来自冰碛坝湖,9个来自基岩坝湖.这一数量是所有已报道GLOF源头数量(75个)的2倍多.综合这些新发现的和已报道的GLOF案例,本文总结出第三极地区GLOF高发的4个热点地区为:喜马拉雅、冈底斯山、念青唐古拉山和天山地区.这些新识别的GLOF案例将为未来的研究提供重要的基础,从而有助于更好地认识和理解第三极地区GLOF的发生机理及真实的发生频率.
