2008 Joint Meeting of The Geological Society of America, Soil Science Society of America, American Society of Agronomy, Crop Science Society of America, Gulf Coast Association of Geological Societies with the Gulf Coast Section of SEPM

Paper No. 5
Presentation Time: 2:50 PM

Comparing Different Spatial and Temporal Scales of Erosion Measurements on Santa Cruz Islands, CA

PERROY, Ryan L.1, ASNER, Greg2, BOOKHAGEN, Bodo1 and CHADWICK, Oliver A.1, (1)Geography, University of California, Santa Barbara, 1832 Ellison Hall, Department of Geography, Santa Barbara, CA 93106, (2)Department of Global Ecology, Carnegie Institution, 260 Panama St, Stanford, CA 94305, perroy@geog.ucsb.edu

Human-induced soil erosion contributes to a host of global problems, including loss of agricultural productivity and desertification. Quantifying this erosion and understanding its impact over timescales ranging from days to centuries is not only important for a better understanding of earth surface processes but also for a variety of economic, social, and planning purposes. Recent technological advances in high resolution Light Detection and Ranging (LiDAR) instruments allow researchers to examine the earth's surface at a level of detail previously unattainable. Topographic data from a variety of instruments at different spatial scales [SPOT satellite-derived DEM (with a pixel size of 5m), Carnegie Airborne Observatory LiDAR DEM (1.5m), RIEGL Model LMS-Z420i terrestrial LiDAR scanner DEM (< 10 cm), and total station survey measurements] were used to produce and compare erosion estimates for a formerly grazed and heavily degraded watershed on Santa Cruz Island, CA. In addition to the topographic data, exploratory depth profile measurements of the short-lived isotopes 210Pb and 137Cs were collected for (24) samples from four sites along a 600m long hillslope transect within the watershed and used to produce an independent erosion rate estimate for a subsection of the study area.