United States Environmental Protection Agency Office of Research and Development National Exposure Research Laboratory Research Abstract Government Performance Results Act (GPRA) Goal #4 Annual Performance Measure #18 Significant Research Findings: Production of Land Cover/Land Use Digital Database for Southwest U.S. (Nevada Ecoregional Component) Scientific The Gap Analysis Program (GAP) is a national interagency program that maps the Problem and distribution of plant communities and selected animal species and compares these Policy Issues distributions with land stewardship to identify vulnerable biotic elements at a regional scale. GAP uses remote sensing (Landsat 7) and Geographic Information System (GIS) technology to assemble and view large amounts of biological and land management data to identify areas (gaps) where conservation efforts may not be sufficient to maintain diversity of living natural resources. Historically, the GAP program has been conducted by individual states; however, this has resulted in inconsistencies in mapped distributions of vegetation types and animal habitat across state lines because of differences in mapping and modeling protocols. This was further compounded from the lack of a national vegetation classification nomenclature. In response to these limitations, GAP embarked on a second- generation effort to conduct the program at a regional scale using 1) a vegetation classification scheme applicable across the U.S.; 2) ecoregional units as the basis for segmenting the landscape into manageable units; and 3) interagency investigator teams with land cover analysis and environmental protection expertise. The program's first formalized multistate effort includes five southwestern states (Arizona, Colorado, Nevada, New Mexico, and Utah) which comprise nearly one-fifth of the conterminous United States. The primary goal is to develop a detailed contemporary land cover database, digital land ownership map, and a set of habitat models for selected terrestrial vertebrate species across the southwestern U.S. This is a collaborative project with the U.S. Geological Survey, Biological Resources Discipline, and it is GAP's first project organized at the regional scale. The project is designed to provide digital land cover and landscape models which are key components for developing large-scale vulnerability assessments. EPA is a partner with USGS (and other agencies) in the project and has lead responsibility for the Nevada ecoregional component. Research The objective of this APM was to develop digital land cover (and other spatial Approach coverages) for the state of Nevada and portions of Arizona and Utah. Additionally, the information was packaged into an easy-use, public access database (i.e., Nevada Geospatial Data Browser) with the purpose of centralizing and distributing the geospatial data used to create land cover, vertebrate habitat models, and land stewardship data produced for the state of Nevada. More than 1.5 billion 30m Landsat pixels have been classified into 125 land cover ------- classes to develop a seamless land cover map for the 5-state area. The regional land cover information is available at the Utah State University server based at http://earth.gis.usu.edu/swgap/. Multi-season satellite imagery (Landsat ETM+) from 1999-2001were used in conjunction with digital elevation (DEM) derived datasets (e.g., elevation, landform, aspect, etc.) to model natural and seminatural vegetation. Land cover classes are drawn from NatureServe's Ecological System concept, with 109 of the 125 total classes mapped at the system level. For the majority of classes, a decision tree classifier was used to discriminate land cover types, while a minority of classes (e.g., urban classes, sand dunes, burn scars, etc.) were mapped using other techniques. Twenty mapping areas, each characterized by similar ecological and spectra characteristics, were modeled independently of one another. These mapping areas, which included a 4-km overlap, were subsequently mosaiced to create the regional dataset. An internal validation for modeled classes was performed by withholding 20% of the sample data as a reference data set. While the modeling area encompassed these five southwestern states, the actual GIS dataset can be downloaded as a subset of the 5-state region using state, county, TNC ecoregion, Bailey ecoregion, and Southwest Regional Gap Analysis Project (SWReGAP) mapping zone configurations. Each file contains a folder with the dataset in Arclnfo grid or ERDAS Imagine format as specified, FGDC metadata file(s), and a .pdf document of land cover class descriptions. The Nevada Geospatial Data Browser (EPA/600/C-05/005) includes complete GIS coverages (n=37) and metadata for the entire state of Nevada. The coverages are available for download and the metadata include important information relative to acquisition, location, processing level, file size, and format. The data browser was externally peer reviewed by six reviewers who are experts in spatial datasets and have direct responsibility for managing and protecting natural resources in the state of Nevada. They included the U.S. Bureau of Land Management (Nevada State Office), Nevada Department of Wildlife, The Nature Conservancy (Nevada Field Office), University of Nevada (State Mapping Advisory Committee), and EPA Region IX. Results and The Southwest is the fastest growing region of the U.S. according to U.S. Census Impact records. This growth results in changes to the landscape and the goods and services it supports. The growth taking place in the West often results in impacts to the air, water, and natural habitats and affects key societal values associated with watershed condition and biodiversity. Regional and local decision-makers are concerned about how continued development will alter living conditions and the ability of the environment to sustain productivity and quality. The digital land cover map and associated coverages developed for the project area will be the most comprehensive digital database ever assembled for the region. They will provide source data for decision analysis relative to resource management, environmental protection, and future conditions. The digital land cover and associated spatial data for the Southwest Regional Gap Analysis Project models were completed in collaboration with the U.S. Geological Survey (Biological Resources Discipline), Utah State University, New Mexico State University, Colorado Division of Wildlife, NatureServe, Nevada Natural Heritage Program (Department of Conservation and Natural Resources), Research Collaboration and Research Products ------- U.S. Bureau of Land Management, U.S. Fish and Wildlife Service, and the Nevada Department of Wildlife. Funding to ORD/NERL/ESD was provided from Interagency Agreement No. RW14939145 from USGS, Biological Resources Discipline. Kepner, W.G., P. Comer, D. Osborne, D. Semmens, and K. Gergely. "The Southwest Regional Gap Analysis Project: A Database Model for Regional Landscape Assessment, Resource Planning, and Vulnerability Analysis." Nineteenth Annual Symposium of the U.S. Regional Association of the International Association for Landscape Ecology: Transdisciplinary Challenges in Landscape Ecology. March 30-April 2, 2004. Las Vegas, NV. Kepner, W.G., D.F. Bradford, and T.D. Sajwaj. "An Approach for Determining Regional Land Cover and Species Habitat Conservation Status in the American Southwest: the Southwest Regional Gap Analysis Project." 36th Annual Meeting of the Desert Fishes Council. 11-14 November 2004. Tucson, AZ. Kepner, W.G., D.F. Bradford, and T.D. Sajwaj. "An Inter-agency Approach for Determining Regional Land Cover and Species Habitat Conservation Status in the American Southwest: the Southwest Regional Gap Analysis Project." EPA Science Forum 2005. 16-18 May 2005. Washington, D.C. The Landscape Ecology Branch of the U.S. Environmental Protection Agency (Las Vegas, NV) with the assistance and collaboration of the University of Idaho (Moscow, ID) and Lockheed-Martin Environmental Services (Las Vegas, NV) has developed the Nevada Geospatial Data Browser, a spatial data archive to centralize and distribute the geospatial data used to create the land cover, vertebrate habitat models, and land ownership/stewardship maps produced for the Nevada ecoregional component of the SWReGAP project. The purpose of the data browser is to provide a one-stop, easy-access product for the user community to assist in natural resource management and improve environmental decision- making. The Nevada Geospatial Data Browser utilizes data from a number of sources and has assembled 37 complete GIS datasets into 10 data categories (land cover maps, land cover training data, digital elevation model, soils and geology, climate data, ecoregional boundaries, political boundaries, hydrology, miscellaneous land cover [i.e., sand dunes and fi re history], and miscellaneous vector data [i.e., roads, quad boundaries, Landsat scene boundaries, cities and towns]) for the entire state of Nevada. The data browser includes important metadata information relative to acquisition, location, processing level, projection, file size, and format. The Nevada Geospatial Data Browser is currently available on-line via the EPA Web site (http://www.epa.gov/nerlesdl/land-sci/gap.htm) and distributed in limited release on DVD. William G. Kepner1, Todd D. Sajwaj2, David F. Bradford1, and Edward J. Evanson3 Nevada Geospatial Databrowser, 2005. 1 U.S. Environmental Protection Agency, Office of Research and Development, Las Vegas, NV 2 University of Idaho, College of Natural Resources, Moscow, ID 3 Lockheed Martin Environmental Services, Las Vegas, NV Future A National Gap Analysis Conference and Interagency Symposium featuring the Research Southwest Regional Gap Analysis Project (Arizona, Colorado, Nevada, New Mexico, and Utah) will be held in Reno, NV, on 6-8 December 2005. The ------- conference has been organized by the U.S. Geological Survey (National Gap Program Office), U.S. Environmental Protection Agency, U.S. Bureau of Land Management, U.S. Fish and Wildlife Service, and the University of Idaho. The Nevada Geospatial Data Browser will be an invited presentation and undoubtedly it will lead to multiple applications, e.g., watershed analysis, fire management, habitat modeling, invasive species monitoring, landscape assessment, vulnerability analysis, and other related research. Contacts for Questions and inquiries can be directed to: Additional William G. Kepner Information U.S. EPA, Office of Research and Development National Exposure Research Laboratory Landscape Ecology Branch P.O. Box 93478 Las Vegas, NV 89193-3478 Phone: 702/798-2193 FAX: 702/798-2208 E-mail: kepner.william@epa.gov Funding for this project was through the U.S. Geological Survey, Biological Resources Division (Interagency Agreement RW14939145) and the U.S. EPA's Office of Research and Development, National Exposure Research Laboratory. The work was conducted by the Environmental Sciences Division. ------- |