The Calhoun Critical Zone Observatory is characterized by a distinct topography with the combination of gullies, interfluves, hillslopes and significantly eroded areas. Understanding the relative importance of different geomorphological processes that led to these conditions in relation to the hydroclimatic and landAuse forcing that have shaped this peculiar landscape is crucial to reconstruct sediment and soil carbon fluxes, predict critical conditions of landscape degradation, and manage their recovery. Toward this main goal, an extension of the analytical theory of the drainage area (which represents a surrogate for water surface runoff responsible for fluvial incision) is presented here to include critical and singular points of the topographic surface. This allows us to represent, in a mathematically consistent way, the evolution of drainage area and ridge and valley lines in landscape evolution models. Preliminary results of backward and forward evolution in time are presented for different formulations of soil creep diffusion and advective river incision to reconstruct possible scenarios at younger stages and explore possible future evolutions.
Sara Bonetti and Amilcare Porporato (2017): Forward and backward evolution of the Calhoun CZO landscape. Critical Zone Science: Current Advances and Future Opportunities, workshop in Arlington, VA, 4-6 June, 2017.
This Paper/Book acknowledges NSF CZO grant support.