Together with rockfall, landslides, and debris flows, snow avalanches are among the most important gravitational natural hazards in mountain regions. On the one hand, forests perform important protective functions against these natural hazards, and on the other hand, ecosystems are also strongly influenced by these disturbances. In this chapter we give an overview of the important interactions between gravitational natural events and mountain ecosystems using the example of avalanches and other snow movements. We also discuss the interactions with other natural disturbances and human land use.