Reconstruction of debris-flow activity in a temperate mountain forest catchment of central Mexico  

作　　者：Osvaldo FRANCO-RAMOS Markus STOFFEL Juan Antonio BALLESTEROS-CANOVAS 

机构地区：[1]Instituto de Geografia. Universidad NacionalAutonoma de Mexico, Ciudad Universitaria Coyoacan, 04510, Mexico [2]Dendrolab.ch, Department of Earth Sciences, University of Geneva, 13 rue des Maraichers, CH-1205 Geneva, Switzerland [3]Climate Change Impacts and Risks in the Anthropocene (C-CIA), Institute for Environmental Sciences, University of Geneva, 66 Boulevard Carl-Vogt, CH-1205 Geneva, Switzerland [4]Department F.-A. Forelfor Environmental and Aquatic Sciences, University of Geneva, 66 Boulevard Carl-Vogt, CH- 1205 Geneva, Switzerland

出　　处：《Journal of Mountain Science》2019年第9期2096-2109,共14页山地科学学报（英文）

基　　金：funded by DGAPA-PAPIIT project IA100619

摘　　要：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.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.

关 键 词：DEBRIS FLOWS La Malinche VOLCANO DENDROGEOMORPHOLOGY TEMPERATE forest Hydrometeorological phenomena 

分 类 号：P[天文地球]