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	Cynthia SA Wallace
	Research Geographer
	Tucson, Arizona
	cwallace@usgs.gov
	520-670-5589
Project Skills:	Ecosystem Science - Extracting temporal and spatial information from remotely sensed data for mapping wildlife habitat.
	Climate Change - Satellite-based analysis of trends in observed phenology of ecosystems and land cover types.
	Land Use/Land Cover Studies - Vegetation, invasive species, land cover and habitat mapping using satellite data coupled with field data
	Tools and Techniques - Arc-GIS, Erdas Imagine, Matlab, S-PLUS
	Remote Sensing - Analysis of spatial structure in satellite images using geostatistical techniques for habitat and land cover mapping. Analysis of multi-temporal multi-spectral satellite data to extract characteristic phenologies of vegetation communities, preferred species habitat and invasive species.

Other Interests/Skills:	Geostatistics.

Geographic Regions:	Southwest United States, Arizona, California.

Current/Recent Projects:	Southern California Multi-hazards demonstration project (MHDP): As a part of the wildfire and debris flow hazards assessment for the Southern California MHDP, this research will characterize the impact of past management activities on loss of native plant communities and replacement by functionally different non-native assemblages. In collaboration with Jon Keeley (USGS-WERC, adjunct at UCLA), I am using satellite data to regionally map occurrences of alien-invasive grasses and forbs in the chaparral communities of Southern California. Based on the distinctive phenology of the alien-invasives, I am selecting a suite of Landsat images to model their current regional distribution. Using historical Landsat data I will extrapolate these results both temporally and spatially to compile a record of vegetation-conversion change across the southern California region back to the 1970s. Phenology and Land Cover Change: Phenology, the study of the timing of biological events, is increasingly regarded as a key to understanding many phenomena that are related to land cover and land use change, global scale climatic change, and human health. Remote sensing of phenology provides a mechanism to move from plant-specific to regional and continental scale studies of phenology. Changing land use has an important impact on surface characteristics that subsequently affect land/atmosphere interactions (e.g., albedo, water, carbon). This project will develop methodologies for summarizing phenological impacts of land cover change by coupling satellite phenology with detailed land cover change information. Regionally-mapped environmental variables for the Mojave Desert: Total cover of perennial and annual vegetation are important measures of a number of processes in the Mojave Desert, including soil-moisture availability, stability of biological soil crusts, and the ability of disturbed areas to recover. Perennial vegetation was derived using Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI) data coupled with pre-existing field transect data and applying step-wise linear regression techniques. Potential annual vegetation was derived using data mining and exploration techniques to reveal appropriate multi-image calculations applied to MODIS-EVI data that correlate with field data collected 2003 and 2005 at 50 plots. These maps are being used in the Mojave Desert tortoise habitat models and in Mojave Desert dust emissions studies.

Recent Publications:	Wallace, C.S.A. and K.A. Thomas, 2008. An Annual Plant Growth Proxy in the Mojave Desert using MODIS-EVI data, Sensors 2008, 8(12), 7792-7808; DOI: 10.3390/s8127792 Wallace, C.S.A. and L. Gass, 2008, Elevation derivatives for Mojave Desert Tortoise Habitat models: U.S. Geological Survey Open-File Report 2008-1283, 7 p. [http://pubs.usgs.gov/of/2008/1283/]. Wallace, C.S.A., R.H. Webb, and K.A. Thomas, 2008. Estimation of perennial vegetation cover in the Mojave Desert using MODIS-EVI data and pre-existing field data. GIScience and Remote Sensing. 45-2, 167-187 Norman, L.M., and Wallace, C.S.A., 2008, Mapping land use/land cover in the Ambos Nogales study area: U.S. Geological Survey Open-File Report 2008-1378, 38 p Webb, R.H., Griffiths, P.G., Wallace, C.S.A., and Boyer, D.E., 2007. Channel response to low-elevation desert fire: the King Valley Fire of 2005: U.S. Geological Survey Data Report DS 275, 52 p. [http://pubs.usgs.gov/ds/2007/275/] Wallace, C.S.A., and Marsh, S.E., 2005. Characterizing the Spatial Structure of Endangered Species Habitat Using Geostatistical Analysis of IKONOS Imagery. International Journal of Remote Sensing, v. 26, no. 12, pp. 2607-2629. Brooks, M.L., J.R. Matchett, C. Wallace, and T. Esque. 2004. Fuels and fire hazard assessment in a desert ecosystem. Arid Lands Newsletter, Vol. 55. Wallace, C.S.A., 2002. Extracting temporal and spatial information from remotely sensed data for mapping wildlife habitat: Tucson, University of Arizona, Ph.D. Dissertation, 198pp. Hutchinson, C.F., S.E. Marsh, C.S.A. Wallace, J.J. Walker, K. Mauz, P.R. Krausman, H. Boyd, R. M. Enns, H. Salazar, L.D. Howery, and E. Trobia, 2000. Informing the Elk Debate: Applying NASA Earth Observing System (EOS) Data to Natural Resource Management Conflicts in the Western States, Tucson: University of Arizona Wallace, Cynthia S.A., J. M. Watts, and S. R. Yool, 2000. Characterizing the Landscape Structure of Vegetation Communities in the Mojave Desert Using Geostatistical Techniques. Computers and Geosciences. v. 26, no. 4, pp. 397-410.

Academic Background:	University of Arizona, Ph.D., Geography; Spatial Analysis&Remote Sensing University of Arizona, M.A., Geography University of Wisconsin-Madison, M.S., Geology University of Minnesota-Duluth, B.S., Geology and Mathematics