Vegetation as a driver of temporal variations in slope stability: The impact of hydrological processes. Issue 10 (29th May 2017)

• Record Type: Journal Article
• Authors: Kim, John H.; Fourcaud, Thierry; Jourdan, Christophe; Maeght, Jean‐Luc; Mao, Zhun; Metayer, James; Meylan, Louise; Pierret, Alain; Rapidel, Bruno; Roupsard, Olivier; de Rouw, Anneke; Sanchez, Mario Villatoro; Wang, Yan; Stokes, Alexia
• Is Part Of: Geophysical research letters. Volume 44:Issue 10(2017)
• Page Start: 4897
• Page End: 4907
• Publication Date: 2017-05-29
• Subjects: landslide -- land use -- factor of safety -- temporal variability -- reliability -- literature review; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1002/2017GL073174
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: Although vegetation is increasingly used to mitigate landslide risks, how vegetation affects the temporal variability of slope stability is poorly understood, especially in earthquake‐prone regions. We combined 3‐year long soil moisture monitoring, measurements of soil physical properties and plant functional traits, and numerical modeling to compare slope stability under paired land uses with and without trees in tropical, subtropical, and temperate landslide‐ and earthquake‐prone regions. Trees improved stability for 5–12 months per year from drawdown of soil moisture and resulted in less interannual variability in the duration of high‐stability periods compared to slopes without trees. Our meta‐analysis of published data also showed that slopes with woody vegetation were more stable and less sensitive to climate and soil factors than slopes with herbaceous vegetation. However, estimates of earthquake magnitude necessary to destabilize slopes at our sites suggest that large additional stabilization from trees is necessary for meaningful protection against external triggers. Key Points: Land uses with trees provided greater slope stability that is also less variable compared to those with shrub or herbaceous communities Analyzing the literature, slope stability with woody vegetation was less sensitive to soil and climate factors than with herbaceous plants To reduce risks from earthquake‐ and rainfall‐induced landslides, the additional stabilization by trees may need to be quite high