Abstract

Understanding the multitude of processes, feedback, and interactions among water, microbes, plants, and porous geological media is crucial for obtaining better predictions about the behavior of Earth’s critical zone in the face of future climatic conditions. Current studies often suffer from the limitations of the spatial scale in which they are performed. By not considering the effects brought by the heterogeneity while moving from pore to landscape scales, important feedback and integrated behavior may be missed, rendering predicted behavior different from that of the natural systems. The time span in which such experiments are executed might also not be suitable for the observation of phenomena typically occurring over years in natural settings. Studying naturally occurring phenomena in situ carries with it the uncertainty about the initial state of the system, and the fact that observations require destructive sampling, which will interfere with the processes under investigation. The investigation of hydrological and biogeochemical evolution of natural systems is thus a challenging task for Earth scientists. The Landscape Evolution Observatory (LEO), a research facility managed by the University of Arizona and located at Biosphere 2, allows for the interdisciplinary investigation of the evolution of artificial hillslopes containing an initially naive mineral assemblage that will be subjected to controlled climate experiments. The LEO’s unique set of instrumentation allows for exceptional observations of energy, water, and carbon fluxes across the three 330 m³ hillslopes. Within the time frame of 10 years of interdisciplinary research, scientists will be able to address important questions related to the interactions among hydrology, geochemistry, and ecology. The LEO project maintains a database open to scientists and practitioners from different domains to address different research questions in a collaborative way. The research done at the LEO has the potential to be a milestone in terrestrial ecosystem research infrastructures.