Dynamic Interactions of Life and its Landscape

One of three proposed research themes for MYRES 2008

Venue: New Orleans, Louisiana

A long-standing paradigm is that physical processes sculpt a landscape and set the template for biological agents, which then act within the constraints of this template. Ecologists have long used information about the landscape and transport processes to model the response of biota. Until recently processes and information have been assumed to flow one way. Current research has begun to focus on potential two-way interactions between the landscape and ecology, however a framework for examining feedbacks and modeling them is still in its infancy.

We want to bring young scientists together to formulate a hypothesis-driven framework for examining geomorphic-ecological feedbacks. An important aspect of our four-day conference will be to explicitly identify the spatial and temporal scales over which various physical, chemical, and biological processes act. Conference discussions on each respective day will be based around problems at three loosely defined spatial ranges: the MICRO-SCALE, the scale of individual and ensembles of particles, from molecules to grains, the scale that includes the complex interactions between biogeochemical cycling and soil geomorphology, the MESO-SCALE, the scale of a fluvial flood plain, or hillslope, to that of an entire basin, and the MACRO-SCALE, from the continental to global scale, the scale shaped by tectonic processes and large scale climate dynamics.

The unifying approach will be the scaling of process times. For example, it has been found that a transition in river channel pattern can occur if the time scale of plant growth is rapid compared to the time scale of channel erosion and migration. Quantifying process timescales of biological growth and physical erosion/deposition will allow a scaling approach to predict under what conditions biota will exert an influence. Such scaling will then motivate process-based modeling to capture these feedbacks at the relevant level of detail for a given problem.

The fourth day will use the formalisms developed in the previous days to address human beings as geologic agents. Humans have already surpassed natural processes in the magnitude of sediment transported per year, and are altering the climate. The challenge will be to explicitly identify feedback loops between humans and their environment that may be modeled using concepts from geology and landscape ecology. The workshop will be held in New Orleans to highlight the delicate and multifaceted nature of human-climate-landscape interactions: delegates will have the option of attending a 3-day field trip on the Mississippi delta. Improving our understanding of the interactions between life and its landscape will have direct bearing on people's livelihoods, and is therefore one of the most pressing research issues in Earth Science research.