Cynthia Wallace (Former Employee)
Science and Products
Filter Total Items: 27
Biodiversity losses and conservation trade-offs: Assessing future urban growth scenarios for a North American trade corridor Biodiversity losses and conservation trade-offs: Assessing future urban growth scenarios for a North American trade corridor
The Sonoran Desert and Apache Highlands ecoregions of North America are areas of exceptionally high plant and vertebrate biodiversity. However, much of the vertebrate biodiversity is supported by only a few vegetation types with limited distributions, some of which are increasingly threatened by changing land uses. We assessed the impacts of two future urban growth scenarios on...
Authors
Miguel L. Villarreal, Laura M. Norman, Cynthia S.A. Wallace, Kenneth G. Boykin
Quantifying soil surface change in degraded drylands: shrub encroachment and effects of fire and vegetation removal in a desert grassland Quantifying soil surface change in degraded drylands: shrub encroachment and effects of fire and vegetation removal in a desert grassland
Woody plant encroachment, a worldwide phenomenon, is a major driver of land degradation in desert grasslands. Woody plant encroachment by shrub functional types ultimately leads to the formation of a patchy landscape with fertile shrub patches interspaced with nutrient-depleted bare soil patches. This is considered to be an irreversible process of land and soil degradation. Recent...
Authors
Joel B. Sankey, Sujith Ravi, Cynthia S.A. Wallace, Robert H. Webb, Travis E. Huxman
Examining wildlife responses to phenology and wildfire using a landscape-scale camera trap network Examining wildlife responses to phenology and wildfire using a landscape-scale camera trap network
Between 2001 and 2009, the Borderlands Jaguar Detection Project deployed 174 camera traps in the mountains of southern Arizona to record jaguar activity. In addition to jaguars, the motion-activated cameras, placed along known wildlife travel routes, recorded occurrences of ~ 20 other animal species. We examined temporal relationships of white-tailed deer (Odocoileus virginianus) and...
Authors
Miguel L. Villarreal, Leila Gass, Laura Norman, Joel B. Sankeya, Cynthia S.A. Wallace, Dennis McMacken, Jack L. Childs, Roy E. Petrakis
Development of a high-resolution binational vegetation map of the Santa Cruz River riparian corridor and surrounding watershed, southern Arizona and northern Sonora, Mexico Development of a high-resolution binational vegetation map of the Santa Cruz River riparian corridor and surrounding watershed, southern Arizona and northern Sonora, Mexico
This report summarizes the development of a binational vegetation map developed for the Santa Cruz Watershed, which straddles the southern border of Arizona and the northern border of Sonora, Mexico. The map was created as an environmental input to the Santa Cruz Watershed Ecosystem Portfolio Model (SCWEPM) that is being created by the U.S. Geological Survey for the watershed. The SCWEPM...
Authors
Cynthia S.A. Wallace, Miguel L. Villarreal, Laura M. Norman
Mapping perennial vegetation cover in the Mojave Desert Mapping perennial vegetation cover in the Mojave Desert
Scientists with the U.S. Geological Survey's Western Geographic Science Center have recently created a regional map of perennial vegetation cover for the Mojave Desert. The scientists used existing field data collected for a variety of previous studies and satellite data available for free through USGS archives to create a calibrated model of percent vegetation cover, an important...
Authors
Cynthia S.A. Wallace
A high-resolution land-use map; Nogales, Sonora, Mexico A high-resolution land-use map; Nogales, Sonora, Mexico
The cities of Nogales, Sonora, and Nogales, Arizona, are located in the Ambos Nogales Watershed, a topographically irregular bowl-shaped area with a northward gradient. Throughout history, residents in both cities have been affected by flooding. Currently, the primary method for regulating this runoff is to build a series of detention basins in Nogales, Sonora. Additionally, the...
Authors
Laura M. Norman, Miguel L. Villarreal, Cynthia S.A. Wallace, Claudia Z. Gil Anaya, Israel Diaz Arcos, Floyd Gray
Modeling habitat of the desert tortoise (Gopherus agassizii) in the Mojave and parts of the Sonoran Deserts of California, Nevada, Utah, and Arizona Modeling habitat of the desert tortoise (Gopherus agassizii) in the Mojave and parts of the Sonoran Deserts of California, Nevada, Utah, and Arizona
Habitat modeling is an important tool used to simulate the potential distribution of a species for a variety of basic and applied questions. The desert tortoise (Gopherus agassizii) is a federally listed threatened species in the Mojave Desert and parts of the Sonoran Desert of California, Nevada, Utah, and Arizona. Land managers in this region require reliable information about the...
Authors
Kenneth E. Nussear, Todd C. Esque, Richard D. Inman, Leila Gass, Kathryn A. Thomas, Cynthia S.A. Wallace, Joan B. Blainey, David M. Miller, Robert H. Webb
Elevation Derivatives for Mojave Desert Tortoise Habitat Elevation Derivatives for Mojave Desert Tortoise Habitat
This report describes the methods used to derive various elevation-derivative grids that were inputted to the Mojave Desert Tortoise Habitat model (L. Gass and others, unpub. data). These grids, which capture information on surface roughness and topographic characteristics, are a subset of the environmental datasets evaluated for the tortoise habitat model. This habitat model is of major
Authors
Cynthia S.A. Wallace, Leila Gass
An annual plant growth proxy in the Mojave Desert using MODIS-EVI data An annual plant growth proxy in the Mojave Desert using MODIS-EVI data
In the arid Mojave Desert, the phenological response of vegetation is largely dependent upon the timing and amount of rainfall, and maps of annual plant cover at any one point in time can vary widely. Our study developed relative annual plant growth models as proxies for annual plant cover using metrics that captured phenological variability in Moderate-Resolution Imaging...
Authors
C.S.A. Wallace, K.A. Thomas
Estimation of perennial vegetation cover distribution in the Mojave Desert using MODIS-EVI data Estimation of perennial vegetation cover distribution in the Mojave Desert using MODIS-EVI data
This paper details a method to create regional models of perennial vegetation cover using pre-existing field data and satellite imagery. Total cover of perennial vegetation is an important ecological attribute of desert ecosystems, including the Mojave Desert, USA, an area of 125,000 km2. Moderate-Resolution Imaging Spectroradiometer Enhanced Vegetation Index (MODIS-EVI) data were...
Authors
C.S.A. Wallace, R. H. Webb, K.A. Thomas
Mapping Land Use/Land Cover in the Ambos Nogales Study Area Mapping Land Use/Land Cover in the Ambos Nogales Study Area
The Ambos Nogales watershed, which surrounds the twin cities of Nogales, Arizona, United States and Nogales, Sonora, Mexico, has a history of problems related to flooding. This paper describes the process of creating a high-resolution, binational land-cover dataset to be used in modeling the Ambos Nogales watershed. The Automated Geospatial Watershed Assessment tool will be used to model...
Authors
Laura M. Norman, Cynthia S.A. Wallace
Channel response to low-elevation desert fire: The King Valley Fire of 2005 Channel response to low-elevation desert fire: The King Valley Fire of 2005
In late September to early October 2005, a fire swept north from the Yuma Proving Grounds and into the Kofa National Wildlife Refuge (NWR), traveling mainly along desert wash systems and low-relief alluvial fans. This fire burned 9,975 ha, moving through xeroriparian systems in washes as well as low-elevation desert ecosystems in King Valley, a major area of designated wilderness in the...
Authors
Robert H. Webb, Peter G. Griffiths, Cynthia S.A. Wallace, Diane E. Boyer
Non-USGS Publications**
Lowry, J.H., Jr., R.D. Ramsey, K. Boykin, D. Bradford, P. Comer, S. Falzarano, W. Kepner, J. Kirby, L. Langs, J. Prior-Magee, G. Manis, L. O’Brien, T. Sajwaj, K.A. Thomas, W. Rieth, S. Schrader, D. Schrupp, K. Schulz, B. Thompson, C. Velasquez, C. Wallace, E. Waller and B. Wolk. 2005. Southwest Regional Gap Analysis Project: Final Report on Land Cover Mapping Methods, RS/GIS Laboratory, Utah State University, Logan, Utah.
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
Hutchinson, C.F.; Marsh, S.E.; Wallace, C.S.A.; Walker, J.J.; Mauz, K.; Krausman, P.R.; Boyd, H.;, Enns, R.M.; Salazar, H.; Howery, L.D.; and Trobia E. 2000. Informing the Elk Debate: Applying NASA Earth Observing System (EOS) Data to Natural Resource Management Conflicts in the Western States: National Park Service Annual Report, University of Arizona. 51p.
Wallace, C.S.A.; Watts, J. M. and Yool, S. R. 2000. Characterizing the Landscape Structure of Vegetation Communities in the Mojave Desert Using Geostatistical Techniques: Computers and Geosciences. v. 26, no. 4, p. 397-410.
O’Brien, J. Prior-Magee, D. Bradford and B. Thompson,2006. Land cover classification and mapping. Chapter 2 in J.S. Prior-Magee, ed. Southwest Regional Gap Analysis Final Report. U.S. Geological Survey, Gap Analysis Program, Moscow, ID.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Filter Total Items: 27
Biodiversity losses and conservation trade-offs: Assessing future urban growth scenarios for a North American trade corridor Biodiversity losses and conservation trade-offs: Assessing future urban growth scenarios for a North American trade corridor
The Sonoran Desert and Apache Highlands ecoregions of North America are areas of exceptionally high plant and vertebrate biodiversity. However, much of the vertebrate biodiversity is supported by only a few vegetation types with limited distributions, some of which are increasingly threatened by changing land uses. We assessed the impacts of two future urban growth scenarios on...
Authors
Miguel L. Villarreal, Laura M. Norman, Cynthia S.A. Wallace, Kenneth G. Boykin
Quantifying soil surface change in degraded drylands: shrub encroachment and effects of fire and vegetation removal in a desert grassland Quantifying soil surface change in degraded drylands: shrub encroachment and effects of fire and vegetation removal in a desert grassland
Woody plant encroachment, a worldwide phenomenon, is a major driver of land degradation in desert grasslands. Woody plant encroachment by shrub functional types ultimately leads to the formation of a patchy landscape with fertile shrub patches interspaced with nutrient-depleted bare soil patches. This is considered to be an irreversible process of land and soil degradation. Recent...
Authors
Joel B. Sankey, Sujith Ravi, Cynthia S.A. Wallace, Robert H. Webb, Travis E. Huxman
Examining wildlife responses to phenology and wildfire using a landscape-scale camera trap network Examining wildlife responses to phenology and wildfire using a landscape-scale camera trap network
Between 2001 and 2009, the Borderlands Jaguar Detection Project deployed 174 camera traps in the mountains of southern Arizona to record jaguar activity. In addition to jaguars, the motion-activated cameras, placed along known wildlife travel routes, recorded occurrences of ~ 20 other animal species. We examined temporal relationships of white-tailed deer (Odocoileus virginianus) and...
Authors
Miguel L. Villarreal, Leila Gass, Laura Norman, Joel B. Sankeya, Cynthia S.A. Wallace, Dennis McMacken, Jack L. Childs, Roy E. Petrakis
Development of a high-resolution binational vegetation map of the Santa Cruz River riparian corridor and surrounding watershed, southern Arizona and northern Sonora, Mexico Development of a high-resolution binational vegetation map of the Santa Cruz River riparian corridor and surrounding watershed, southern Arizona and northern Sonora, Mexico
This report summarizes the development of a binational vegetation map developed for the Santa Cruz Watershed, which straddles the southern border of Arizona and the northern border of Sonora, Mexico. The map was created as an environmental input to the Santa Cruz Watershed Ecosystem Portfolio Model (SCWEPM) that is being created by the U.S. Geological Survey for the watershed. The SCWEPM...
Authors
Cynthia S.A. Wallace, Miguel L. Villarreal, Laura M. Norman
Mapping perennial vegetation cover in the Mojave Desert Mapping perennial vegetation cover in the Mojave Desert
Scientists with the U.S. Geological Survey's Western Geographic Science Center have recently created a regional map of perennial vegetation cover for the Mojave Desert. The scientists used existing field data collected for a variety of previous studies and satellite data available for free through USGS archives to create a calibrated model of percent vegetation cover, an important...
Authors
Cynthia S.A. Wallace
A high-resolution land-use map; Nogales, Sonora, Mexico A high-resolution land-use map; Nogales, Sonora, Mexico
The cities of Nogales, Sonora, and Nogales, Arizona, are located in the Ambos Nogales Watershed, a topographically irregular bowl-shaped area with a northward gradient. Throughout history, residents in both cities have been affected by flooding. Currently, the primary method for regulating this runoff is to build a series of detention basins in Nogales, Sonora. Additionally, the...
Authors
Laura M. Norman, Miguel L. Villarreal, Cynthia S.A. Wallace, Claudia Z. Gil Anaya, Israel Diaz Arcos, Floyd Gray
Modeling habitat of the desert tortoise (Gopherus agassizii) in the Mojave and parts of the Sonoran Deserts of California, Nevada, Utah, and Arizona Modeling habitat of the desert tortoise (Gopherus agassizii) in the Mojave and parts of the Sonoran Deserts of California, Nevada, Utah, and Arizona
Habitat modeling is an important tool used to simulate the potential distribution of a species for a variety of basic and applied questions. The desert tortoise (Gopherus agassizii) is a federally listed threatened species in the Mojave Desert and parts of the Sonoran Desert of California, Nevada, Utah, and Arizona. Land managers in this region require reliable information about the...
Authors
Kenneth E. Nussear, Todd C. Esque, Richard D. Inman, Leila Gass, Kathryn A. Thomas, Cynthia S.A. Wallace, Joan B. Blainey, David M. Miller, Robert H. Webb
Elevation Derivatives for Mojave Desert Tortoise Habitat Elevation Derivatives for Mojave Desert Tortoise Habitat
This report describes the methods used to derive various elevation-derivative grids that were inputted to the Mojave Desert Tortoise Habitat model (L. Gass and others, unpub. data). These grids, which capture information on surface roughness and topographic characteristics, are a subset of the environmental datasets evaluated for the tortoise habitat model. This habitat model is of major
Authors
Cynthia S.A. Wallace, Leila Gass
An annual plant growth proxy in the Mojave Desert using MODIS-EVI data An annual plant growth proxy in the Mojave Desert using MODIS-EVI data
In the arid Mojave Desert, the phenological response of vegetation is largely dependent upon the timing and amount of rainfall, and maps of annual plant cover at any one point in time can vary widely. Our study developed relative annual plant growth models as proxies for annual plant cover using metrics that captured phenological variability in Moderate-Resolution Imaging...
Authors
C.S.A. Wallace, K.A. Thomas
Estimation of perennial vegetation cover distribution in the Mojave Desert using MODIS-EVI data Estimation of perennial vegetation cover distribution in the Mojave Desert using MODIS-EVI data
This paper details a method to create regional models of perennial vegetation cover using pre-existing field data and satellite imagery. Total cover of perennial vegetation is an important ecological attribute of desert ecosystems, including the Mojave Desert, USA, an area of 125,000 km2. Moderate-Resolution Imaging Spectroradiometer Enhanced Vegetation Index (MODIS-EVI) data were...
Authors
C.S.A. Wallace, R. H. Webb, K.A. Thomas
Mapping Land Use/Land Cover in the Ambos Nogales Study Area Mapping Land Use/Land Cover in the Ambos Nogales Study Area
The Ambos Nogales watershed, which surrounds the twin cities of Nogales, Arizona, United States and Nogales, Sonora, Mexico, has a history of problems related to flooding. This paper describes the process of creating a high-resolution, binational land-cover dataset to be used in modeling the Ambos Nogales watershed. The Automated Geospatial Watershed Assessment tool will be used to model...
Authors
Laura M. Norman, Cynthia S.A. Wallace
Channel response to low-elevation desert fire: The King Valley Fire of 2005 Channel response to low-elevation desert fire: The King Valley Fire of 2005
In late September to early October 2005, a fire swept north from the Yuma Proving Grounds and into the Kofa National Wildlife Refuge (NWR), traveling mainly along desert wash systems and low-relief alluvial fans. This fire burned 9,975 ha, moving through xeroriparian systems in washes as well as low-elevation desert ecosystems in King Valley, a major area of designated wilderness in the...
Authors
Robert H. Webb, Peter G. Griffiths, Cynthia S.A. Wallace, Diane E. Boyer
Non-USGS Publications**
Lowry, J.H., Jr., R.D. Ramsey, K. Boykin, D. Bradford, P. Comer, S. Falzarano, W. Kepner, J. Kirby, L. Langs, J. Prior-Magee, G. Manis, L. O’Brien, T. Sajwaj, K.A. Thomas, W. Rieth, S. Schrader, D. Schrupp, K. Schulz, B. Thompson, C. Velasquez, C. Wallace, E. Waller and B. Wolk. 2005. Southwest Regional Gap Analysis Project: Final Report on Land Cover Mapping Methods, RS/GIS Laboratory, Utah State University, Logan, Utah.
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
Hutchinson, C.F.; Marsh, S.E.; Wallace, C.S.A.; Walker, J.J.; Mauz, K.; Krausman, P.R.; Boyd, H.;, Enns, R.M.; Salazar, H.; Howery, L.D.; and Trobia E. 2000. Informing the Elk Debate: Applying NASA Earth Observing System (EOS) Data to Natural Resource Management Conflicts in the Western States: National Park Service Annual Report, University of Arizona. 51p.
Wallace, C.S.A.; Watts, J. M. and Yool, S. R. 2000. Characterizing the Landscape Structure of Vegetation Communities in the Mojave Desert Using Geostatistical Techniques: Computers and Geosciences. v. 26, no. 4, p. 397-410.
O’Brien, J. Prior-Magee, D. Bradford and B. Thompson,2006. Land cover classification and mapping. Chapter 2 in J.S. Prior-Magee, ed. Southwest Regional Gap Analysis Final Report. U.S. Geological Survey, Gap Analysis Program, Moscow, ID.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.