Although it is widely understood that organisms directly and indirectly affect erosion and transport processes, their long-term contribution to the evolution of landscapes is not well known. This deficit is rooted in the fact that biotic influences are complex and difficult to disentangle from climatic influences. In this project, we examine the influence of biota on erosion and sediment transport in the framework of a threshold-stochastic stream power model of river incision. We test the hypothesis that biota, the characteristics of soils, and vegetation, influence river incision primarily by modulating the magnitude-frequency distribution of flood events (Figure 1).
To achieve this goal, we will focus on 4 granitic areas that are distributed across a large climate-and-vegetation gradient in the Coastal Cordillera of Central Chile (Figure 2), and address three key objectives:
Our project thus combines geological/geochemical with ecohydrological/geoecological methods for bridging different time scales, from the stream response to individual rain events to the long-term effect on landscape development.
Eva Paton (Ecohydrology). Institute of Ecology, Technical University of Berlin, Germany
Luca Mao (Fluvial Geomorphology). Pontificia Universidad Catolica de Chile, Santiago, Chile
Claudio Meier (Civil Engineering). University of Memphis, USA