Thursday, August 10, 2017: 1:30 PM-5:00 PM
D135, Oregon Convention Center
Organizer:
Charles M. Crisafulli, USDA Forest Service
Co-organizer:
Frederick J. Swanson, USDA Forest Service, Pacific NW Research Station
Moderator:
Andrés Holz, Portland State university
Volcanism is a powerful agent of environmental change altering ecosystems around the world, often in profound ways. Of the ca. 1550 volcanoes in the Smithsonian/USGS catalog only a few dozen erupt sub-aerially each year. A key feature of volcanism is the transfer of inorganic materials from the earth’s crust to the surface, thus creating new substrates, and in some cases new landforms, for biota to colonize. Eruptions create complex mosaics of disturbance types (e.g., lava flows, pyroclastic flows, mudflows, tephra falls), that may influence landscapes and waters over large spatial scales (e.g., 1000s-100,000 km2). Spatially, the intensity of each disturbance type lessens with distance from the vent (e.g., crater, caldera) creating distinct disturbance gradients ranging from modest changes in community structure to obliteration of all life. Temporally, disturbance effects on biota and ecosystem processes range from ephemeral to thousands of years, or longer. Disturbance mechanisms of volcanism include heat, burial, abrasion, canopy loading, impact force, chemical toxicity and thus have commonalities to several other forms of natural disturbance such as wildfire, floods, extreme ice/snow storms and wind events (e.g., hurricanes and tornadoes). This affords lessons from volcano ecology to have relevance to many other, more common types of disturbance. This session will convene ecologists with long histories of work on volcanoes from hot spots of volcano ecology research around the world to present results and discuss key synthetic findings from long-term studies in the United States, Chile, Japan, Russia, Indonesia and Iceland. We will begin with an overview of the field of volcano ecology and a synthesis of the geography of eruption sites and those studied by ecologists, their distribution among biomes of the world, the prevalence of volcanic disturbance types investigated as well as the biota and ecosystem processes studied, based on a review of >900 published papers. This will be followed by presentations of several integrated syntheses from long-term volcanic research sites focusing on themes including patterns and processes of organism survival, colonization, community assembly, succession, geological-ecological interactions, soil genesis, and evolutionary processes. The session will end with a presentation that integrates and synthesizes findings across sites and compares volcanism with other forms of intense large-scale natural disturbance, and suggest the path forward in volcano ecology research.