Scaling ecological data to reveal emergent properties of ecosystems

Background/Question/Methods

Ecosystems are complex systems.  In being so, they consist of a large number of interconnected, non-linear biophysical processes that operate with positive and negative feedbacks across a spectrum of time and space scales.  Complex systems also exhibit scale-emergent properties, where the functioning of the whole is different than that of the sum of the parts.

Eddy covariance measurements, associated with the global network FLUXNET, measures ecosystem-level metabolic fluxes on time scales from hours to decades.   Hence, this method is able to see how a collection of leaves, plants and soils work together at the ecosystem scale.

 Results/Conclusions

We will dive into this database and extract a number of scale emergent properties.  Among them are differences in how ecosystem and leaf photosynthesis respond to light and how soil respiration depends upon the presence/absence and physiological activity of plant.  At the landscape scale, we will examine how surface energy fluxes affect the growth and status of the planetary boundary layer; it is connected to the partitioning of energy into sensible and the latent heat, which generate clouds, which affect the fraction of diffuse and direct radiation, which affect the light use efficiency of the ecosystem.  PBL-surface feedbacks also affect humidity deficits in the boundary layer, which alter the surface conductance to water transfer and the rates of latent and sensible heat exchange.