Seminar: Dr. John Day, LSU Dept. of Oceanography and Coastal Sciences

UNC Marine Sciences’ Professor Jaye Cable hosts a seminar presented by John Day, Ph.D.

Presenter Affiliation: Louisiana State University Dept. of Oceanography and Coastal Sciences

Title: The Impact of 21^st Century Megatrends on Deltaic Sustainability

Abstract: The megatrends of the 21^st century including climate change and resource scarcity will strongly impact deltas.  They are among the most productive and economically important of global ecosystems but they are also among the most threatened by human activities.  Delta sustainability must be considered within the context of global biophysical and socioeconomic constraints that include thermodynamic limitations, scale and embeddedness, and constraints at the level of the biosphere/geosphere.  The development, functioning, and sustainability of deltas are the result of external and internal inputs of energy and materials. Modern deltas developed over the past several thousand years with relatively stable global mean sea level, predictable material inputs from drainage basins and the sea, and as extremely open systems. Human activity has changed these conditions to make deltas less sustainable, in that they are unable to persist through time structurally or functionally.  Deltaic sustainability can be considered from geomorphic, ecological, and economic perspectives, with functional processes at these three levels being highly interactive. There is a growing understanding that the trajectories of global environmental change and cost of energy will make achieving delta sustainability more challenging and limit options for management. Delta sustainability depends on the characteristics of different delta types including those in arid regions, those with high and low energy-intensive management systems, deltas below sea level, tropical deltas, and Arctic deltas.  Success in sustainable delta management will depend on utilizing natural delta functioning and an ecological engineering approach.