Thursday, August 11, 2016: 1:30 PM-5:00 PM
Grand Floridian Blrm E, Ft Lauderdale Convention Center
Organizer:
Michael S. Ross, Florida International University
Co-organizers:
Loretta L. Battaglia, Southern Illinois University; and
Skip Van Bloem, Clemson University
Moderator:
Michael S. Ross, Florida International University
Ecological resilience is typically defined as the capacity of an ecosystem to return to its original state and location following a perturbation. However, where ecosystems arranged along an environmental gradient are subjected to a strong, directional stressor, resilience at a broader scale, i.e., landscape resilience, may be achieved through a shift en masse away from the source of stress.
Examples of resilience-in-place, landscape resilience, and non-resilience may be found among coastal ecosystems that occupy the marine-terrestrial interface and are subject to sea level change, a directional press disturbance. Though eustatic sea level is rising everywhere, relative sea level varies globally and among North American coast settings. Where relative sea level is declining, the components of coastal landscapes undergo a “seaward” shift, a situation that occurred on coastlines after the last ice age, and that still exists on high latitude coastlines. In other coastal settings, resilience may be realized even in the face of sea level rise when this rate is matched by the accretion of organic material and trapping of inorganic sediments, allowing ecosystems to persist in situ. Elsewhere, in cases where rates of sea level rise exceed accretion capacity, upslope migration of the entire gradient of coastal ecosystems is necessary for landscape resilience. These shifts are fundamentally driven by a sequential, retreat-advance dynamic, but can be disrupted where the rate of physical change outpaces the ecological capacity for lateral migration, or where ecosystems respond at different rates. Human infrastructure, geological or biological barriers, or changes in disturbance regime may also impede movement, leading to reduced resilience and coastal squeeze.