Rainfall thresholds for the triggering of landslides considering previous soil moisture conditions (Asturias, NW Spain)

[EN] Given its geological and climatic conditions and its rugged orography, Asturias is one of the most landslide prone areas in the North of Spain. Most of the landslides occur during intense rainfall episodes. Thus, precipitation is considered the main triggering factor in the study area, reaching...

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Detalles Bibliográficos
Autores: Valenzuela Mendizábal, Pablo, Domínguez Cuesta, María José, Mora García, Manuel Antonio, Jiménez Sánchez, Montserrat
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2017
País:España
Institución:Universidad de León
Repositorio:BULERIA. Repositorio Institucional de la Universidad de León
OAI Identifier:oai:buleria.unileon.es:10612/25965
Acceso en línea:https://link.springer.com/article/10.1007/s10346-017-0878-8
https://hdl.handle.net/10612/25965
Access Level:acceso abierto
Palabra clave:Ecología. Medio ambiente
Geodinámica
Geografía
Geología
Landslide
Rainfall
I-D threshold
Soil moisture
Asturias
25 Ciencias de la Tierra y del Espacio
2506 Geología
2506.07 Geomorfología
Descripción
Sumario:[EN] Given its geological and climatic conditions and its rugged orography, Asturias is one of the most landslide prone areas in the North of Spain. Most of the landslides occur during intense rainfall episodes. Thus, precipitation is considered the main triggering factor in the study area, reaching average annual values of 960 mm. Two main precipitation patterns are frequent: (i) long-lasting periods of moderate rainfall during autumn and winter and (ii) heavy short rainfall episodes during spring and early summer. In the present work, soil moisture conditions in the locations of 84 landslides are analysed during two rainfall episodes, which represent the most common precipitation patterns: October–November 2008 and June 2010. Empirical data allowed the definition of available water capacity percentages of 99–100% as critical soil moisture conditions for the landslide triggering. Intensity-duration rainfall thresholds were calculated for each episode, considering the periods with sustained high soil moisture levels before the occurrence of each analysed landslide event. For this purpose, data from daily water balance models and weather stations were used. An inverse relationship between the duration of the precipitation and its intensity, consistent with published intensity-duration thresholds, was observed, showing relevant seasonal differences