- Who: Peter Vitousek, Ph.D., Stanford University, Dept. of Biology
- What: Download the file (pdf)
- Where: Building B50 Auditorium
- When: 10:30 am to 12:00 noon, March 1, 2012
- Why: About the Distinguished Scientist Seminar Series
- Video Replay: https://vimeo.com/38183034/
More Information: Peter Vitousek has been on the faculty at Stanford University since 1984. His research interests include: evaluating the global cycles of nitrogen and phosphorus, and how they are altered by human activity; determining the effects of invasive species on the workings of whole ecosystems; understanding how the interaction of land and culture contributed to the sustainability of Hawaiian society before European contact; and more generally using the extraordinary ecosystems of Hawaii (where he was born) as models for understanding how the world works. He is a Fellow of the National Academy of Sciences and the American Academy of Arts and Sciences, and was awarded the 2010 Japan Prize. He is also the director of the Emmett Interdisciplinary Program in Environment and Resources and co-director of the First Nations Futures Institute.
Abstract: For many years, we have been making use of the Hawaiian Islands as models for understanding how soils and ecosystems develop and function. Results of this research show that the properties of soils exhibit sharp thresholds in both space and time, places where soil properties change abruptly with a small additional change in forcing. We have identified three major thresholds in Hawaiian soils – one associated with the accumulation of carbonate in dry soils, a second associated with the depletion of primary minerals in the rooting zone, and a third associated with iron reduction and phosphorus mobility.
Islands also can be useful systems for understanding human-land interactions. The Polynesian Islands are particularly valuable; they were colonized relatively recently by a single dynamic culture, they developed distinctive cultures on the very different islands of Polynesia, and these cultures faced the challenges of making a transition to sustainability in isolation, dependent almost entirely on their own resources. We show that intensive Hawaiian agriculture in rain-fed areas developed in one particular soil domain, the region between the carbonate threshold and the mineral depletion threshold. That domain is distributed unevenly across the Hawaiian Archipelago, shaping the potential pathways of agricultural intensification on different islands and so contributing to patterns of human-land interaction and the development of social and cultural complexity within Hawaii. We are now extending this analysis to other Polynesian islands.