William Dietrich

William Dietrich

Professor (Earth & Planetary Science and Geography)
Seeking mechanistic, quantitative understanding of the form and evolution of landscapes, linkages between ecological and geomorphic processes, building tools to tackle pressing environmental problems

313 McCone Hall
510 642-2633

Bill Dietrich has appointments in the Earth and Planetary Science Department, the Department of Geography and the Earth Sciences Division of Lawrence Berkeley National Laboratory. He is affiliated with the Archeological Research Facility, the Energy and Resources Group, the Earth Resources Center, and the California Water Resources Research Center (Lawrence Berkeley National Laboratory).

He is currently supervising or sharing in the supervision of six graduate students. In addition two post-doctoral fellows are currently working with him. The projects by the students and post-docs are described on the Berkeley Geomorphology Group website.

Research group projects
I work closely with graduate students and post-doctoral fellows on a wide range of problems. Our research projects share a common theme: we are seeking mechanistic, quantitative understanding of the form and evolution of landscapes. In addition, we are seeking linkages between ecological and geomorphic processes, and building tools to tackle pressing environmental problems. Our approach is to use field work, laboratory experiments and numerical modeling to quantify and explore geomorphic processes. One result of these combined approaches has been the development of “geomorphic transport laws” that can be field calibrated and used in both landscape evolution modeling and in practical applications. We have used high resolution laser altimetry to create detailed topographic maps and cosmogenic nuclide analysis to obtain estimates of rates of processes and to quantify transport laws. Numerical modeling work is underway to exploit both the high resolution topography and rate measurements to explore controls on landscape morphology.

A crucial link between tectonics and landscape evolution is river incision and valley development. Our group is exploring river incision into bedrock by debris flows and the role of sediment loading on rates of incision by fluvial processes (graduate students John Stock and Leonard Sklar). The hydraulics and sediment transport in steep channels (greater than about 5 to 8% ), which lie at the transition between debris flow and fluvial dominated channels, are poorly understood and little studied. Jim Kirchner (Berkeley), Dave Furbish (Florida State University) and I are working with Elowyn Yager (graduate student) on laboratory and field experiments to explore these common yet understudied channels. Geoff Day (graduate student) and I are working on what controls the rate of floodplain deposition on a large lowland river in Papua New Guinea (The Fly River) where sediment waste from a large mine provides a strong chemical tracer (as well as create significant environmental change). This work contributes to floodplain deposition model development and testing by Gary Parker (U. Minnesota) and is located at a site under consideration for the NSF-sponsored MARGINS project. Joel Rowland (graduate student) is developing research on the mechanics of floodplain channel formation by sediment laden flows that are injected into still water. Douglas Allen (graduate student) is completing a project that has lead to the development of a simple model for predicting stream temperature throughout a watershed on the hottest low flow day of the year. Finally Taylor Perron (graduate student) and I are collaborating with Alan Howard (U. Virginia) on a new project to explore what processes may be responsible for creating relatively recent channels on steep slopes on Mars. Mauro Casadei (post-doc) and Yantao Cui (Stillwater Sciences) are working with Norm Miller (Lawrence Berkeley National Laboratory, nlmiller@lbl.gov) and me to link his models of precipitation downscaling and runoff with models for shallow landsliding, debris flow runout and sediment flux through river networks.

On the practical application side, we are spending considerable to develop digital terrain tools for tackling problems of watershed analysis, especially cumulative watershed effects issues, Total Maximum Daily Load restrictions, and linkages between salmonid populations, habitat change and effects of timber harvesting practices. We have developed and validated a model (SHALSTAB) for predicting the spatial pattern of relative shallow landslide potential. Many groups are now testing this model. The model is serving to guide forest practices in some watersheds in the Pacific Northwest. It is also being considered for use in urban landslide hazard mapping.

Additional Collaborations
Bill Dietrich is involved in several collaborative projects led by others. He is working with Meg Conkey (Department of Anthropology) to apply his soil production and transport model to the prediction of the location and fate of artifacts left by late Pleistocene people in the southern France. For many years he has been collaborating with Ana Coelho Neto (Universidade Federal do Rio de Janeiro, ananetto@openlink.com.br) in a study to explore landscape response to climate change in southeastern Brasil (with a particular focus on the Pleistocene-Holocence transition). He is collaborating David Furbish (Florida State University, furbish@quartz.gly.fsu.edu) on the underlying mechanisms responsible for diffusive like transport of soil on hillslopes. He is working with Mary Power (UC Berkeley, mepower@berkeley.edu) to pursue linkages between geomorphic processes and food web structure and dynamics. Strong collaborations are underway with Frank Ligon (Frank@Still-watersci.com) and colleagues at Stillwater Sciences (Berkeley) to develop tools for quantifying the influence of landuse on river ecosystems.

Selected publications

Dietrich, W. E., G. Day and G. Parker, 1999, The Fly River, Papua New Guinea: inferences about river dynamics, floodplain sedimentation and fate of sediment, in A. Miller and A. Gupta (edt), Varieties of Fluvial Form, J. Wiley, p. 345-376.

Roering, J. J., J. W. Kirchner, and W. E. Dietrich, 1999, Evidence for non-linear, diffusive sediment transport on hillslopes and implications for landscape morphology, Water Resources Research, v. 35, no.3, p. 853-870

Heinsath, A. M., J. Chappell, W. E. Dietrich, K. Nishiizumi, R. C. Finkel, 2000, Soil production on a retreating escarpment in southeastern Australia, Geology, 28(9), p. 787-790.

Dietrich, W.E., D. Bellugi, and R. Real de Asua, 2001, Validation of the shallow landslide model, SHALSTAB, for forest management, in M..S. Wigmosta, and S. J. Burges, editors, Land Use and Watersheds: Human influence on hydrology and geomorphology in urban and forest areas; Amer. Geoph. Union, Water Sciene and Application 2, p.195-227.

Heimsath, A. M., W. E. Dietrich, K. Nishiizumi, R. C. Finkel, 2001, Stochastic processes of soil pro-duction and transport: erosion rates, topographic variation, and cosmogenic nuclides in the Ore-gon Coast Range, Earth Surface Processes and Landforms, v26, p.531-552.

Roering, J. J, J. W. Kirchner, L. S. Sklar, and W. E. Dietrich, 2001, Hillslope evolution by nonlinear creep and landsliding: an experimental study, Geology, 29 (2), p.143-146.