Background/Question/Methods In 1998 and 2005 two tropical storms triggered hundreds to thousands of landslides in the Sierra Madre de Chiapas of southwestern Mexico.  A region that was particularly affected by these storms and associated landslides was the El Triunfo Biosphere Reserve (ETBR), an area of ~120,000 hectares that was set aside eighteen years ago to protect the elevated diversity of organisms and ecosystems of this mountain range while promoting its sustainable development.  Extensive landsliding in the ETBR raises numerous questions about the large-scale dynamics and conservation of these and other mountain ecosystems worldwide.  
Results/Conclusions

We combined the classification of IRS and SPOT images with spatial analyses to examine the role of land cover/land use and reserve zonation (buffer versus core areas) on the distribution and extent of landsliding.  We found that in 1998 roughly 5,000 and 1,500 ha of the buffer (6%) and core (6%) zones lost the forest and soil due to landsliding  In 2005 this area was equivalent to ~3,000 and 1,000 for buffer and core zones, respectively. The most affected ecosystems in the buffer zone were the evergreen tall and medium forests, cloud forests, and induced pastures. We discuss the implications of our work for the management of the ETBR, including the role of protected areas in the conservation of landsliding as a key process driving the large-scale dynamics of mountainscapes.