Oral Sessions - Landscape Models to Predict Future Change - Day 2 Chair(s): Neale, Anne ¹, ¹ Landscape Ecology Branch, Las Vegas, NV
Friday, April 2, 2004 3:00 PM - 4:40 PM Apollo Room 1-2

Evaluating Landscape Change and Hydrological Consequences in a Semi-arid Environment. Kepner, William¹, Semmens, Darius², Watts, Christopher³, Bassett, Scott ⁴, Mouat, David⁴, Goodrich, David², ¹ US Environmental Protection Agency, Las Vegas, NV, USA² USDA, Agricultural Research Service, Tucson, AZ, USA³ Instituto del Medio Ambiente y el Desarrollo Sustentable del Estado de Sonora, Hermosillo, Sonora, Mexico⁴ Desert Research Institute, Reno, NV, USA

ABSTRACT- During the past two decades, important advances in the integration of remote imagery, computer processing, and spatial analysis technologies have been used to better understand the distribution of natural communities and ecosystems, and the ecological processes that affect these patterns. These technologies provide the basis for developing landscape measurements that can be integrated within hydrologic models to determine long-term change and make predictive inferences about the future. This case study employs a system of land cover maps generated from a multi-date satellite imagery database which incorporates Landsat Multi-Spectral Scanner (MSS) imagery from the early 1970s, mid 1980s, and early 1990s and Landsat Thematic Mapper (TM) imagery from 1997 for the San Pedro River (U.S./Mexico). Past and future landscape changes were examined relative to their impact on surface water conditions, e.g. sediment yield and surface runoff. Hydrological outputs were estimated for the years 1973-1997 and predicted twenty years into the future via the integration of scenario analysis with hydrological process and land use models.

KEY WORDS: hydrological models, alternative futures analysis, scenario analysis, landscape change , San Pedro River (Arizona/Sonora)