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Abstract

Landscape memory, the set of processes conferring resistance of disturbed areas to further disturbance, is critical for our understanding of ecosystem dynamics at large scales. Although evidence from diverse disciplines suggests that the conditions at the time of disturbance as well as the history of past disturbances are central to landscape memory, there have been few attempts to explore their relative contribution in systems in which ecological and geomorphic processes strongly interact. Among these systems, mountains disturbed by landslides stand out due to their regional and global importance. In mountainous regions, topographic and morphological attributes are known to contribute to landscape memory. However, vegetation attributes also influence geomorphic conditions in these systems, and in this way may play a role in forming patterns of landslide patterns as well. In this study I use degree of landslide overlap in combination with bioclimatic and topographic variables to explore landscape memory using a species distribution model (SDM) approach. Focusing on the Sierra de Las Minas of Guatemala, I created landslide inventories using remotely sensed data, then use these to identify overlapping and recovered landslide areas and model their relationship with bioclimatic and topographic variables. Irrespective of year, landslide occurrence was explained by three bioclimatic (positive relationship with isothermality, temperature seasonality, and precipitation during the wettest month of the year) and three terrain (negative relationship with aspect and curvature, and positive relationship with slope) variables. Overall, I observed little overlap among landslide populations. The number and type of variables explaining landslide overlapping and non-overlapping areas varied by period of observation but in general varied in significance far more than variables explaining initial occurrences. The implications of my results are three-fold. First, the retention of three bioclimatic variables in the models suggests that climate can alone, or through its effect on vegetation, influence the occurrence of landslides as well as their recovery. Second, landscape memory seems to play an important role in preventing reoccurrence as shown by the study area’s great potential for recovery after disturbance. Lastly, increased precipitation and more extreme temperatures may increase landslide burden in the future.

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