Building a Desert Data Clearinghouse

The Mojave Desert Ecosystem Program (MDEP) of California faces the formidable task of building a clearinghouse for geospatial data covering 50 million acres of desert lands. Making the project even more challenging is the need to serve that data to dozens of organizations engaged in a variety of natural resource preservation activities.

Creation of the clearinghouse has been prompted by unprecedented growth in the Mojave Desert ecosystem region that has resulted in increasing, and often conflicting, demands on the area's limited resources. Included in the region are Joshua Tree and Death Valley National Parks, the Mojave National Preserve, five U.S. military installations, and numerous growing communities.

To their credit, the Bureau of Land Management (BLM), the Fish and Wildlife Service, the Department of Defense, the Department of the Interior, and several State and private agencies have assumed responsibilities for environmental assessment and habitat protection projects in these areas. But therein lies part of the problem.

"Most have good spatial data sets for inside their boundaries, but our mission is to encourage and facilitate an ecosystem approach to their environmental projects," says Jeff Foisy, GIS analyst/data manager for MDEP. "Our goal is to provide them with data sets that extend beyond their boundaries so they can take into account the ecological patterns and processes of the surrounding areas."

MDEP is responsible for desert regions in Southern California, Nevada, Arizona, and Utah. As a major landholder, the Department of Defense has spearheaded the plan to build a database of satellite imagery, habitat inventories, land cover layers, and other spatial data that will be accessible to any organization, public or private, that is taking part in sustainable land management projects in the area.

"These end users range from very sophisticated users of GIS technology to those having minimal experience with spatial data," says Foisy. "The real challenge of building a data clearinghouse is generating products they all can use."

MDEP believes it has solved this problem with two recent software acquisitions-ERDAS IMAGINE geographic imaging software for processing geospatial data and Esri's ArcIMS for serving the processed data products over the Web.

An Easy Choice

For MDEP, which has equipped its Barstow, California, headquarters with ArcInfo products since its inception in 1992, the selection of ERDAS IMAGINE software was not a difficult choice. In recent years, ERDAS (an Esri Business Partner) and Esri have jointly developed several software products to ensure complete compatibility of data sets with little or no conversion.

"On a project basis, using ERDAS and Esri products together effectively eliminates time and processor intensive reformatting, reduces the risk of file corruption, and guarantees that our interagency users will be provided with standardized data products that work with their systems," says Foisy.

The primary application for ERDAS IMAGINE software will be to process Landsat, SPOT, IKONOS, and Indian IRS satellite imagery to generate land cover classification layers pertaining to geology, topography, geomorphology, and vegetation. In some cases, the ERDAS software will also be used to integrate elevation data and vector layers with imagery to create more complex GIS products.

"The advantage of using ERDAS IMAGINE to generate these products is that they will be compatible with any level of user expertise," says Foisy. "They can be integrated as a component in a multidata set GIS analysis or they can be viewed as stand-alone information sources by non-GIS users."

Putting Processed Data to Use

One organization that is considered a sophisticated GIS user is the Geospatial Information and Services group at the Marine Corps Air Ground Combat Center in Twentynine Palms, California. This unit supplies the geospatial information needed for the base to ensure that its military training has minimal impact on natural habitats. One of its main concerns is the desert tortoise, an endangered species in the area.

"Twentynine Palms realizes it is one piece of the overall ecosystem, and we rely on spatial data to understand the habitat of the desert tortoise around our base," says Paul Kip Otis-Diehl, the Geospatial Information and Services officer in the base's Marine Air Ground Task Force.

When the base utilizes spatial data from MDEP, it typically integrates the MDEP data layers with other data sets already in its GIS. For instance, during a recent desert tortoise habitat mapping project, Otis-Diehl's group merged vegetation coverage layers supplied by MDEP with high-resolution satellite imagery that had been processed in the base GIS/Remote Sensing lab.

As a result, Twentynine Palms can create end products and perform advanced data analyses independent of the information found on the MDEP site.

Another benefit of having the combined image processing and GIS capabilities of ERDAS IMAGINE and Esri software is that MDEP can offer enhanced analysis services to some clients who do not have sufficient spatial data experience or GIS capacity to conduct their own analysis.

For example, MDEP recently participated in a spatial modeling exercise with the BLM, Desert Research Institute, and Utah State University. MDEP used the geographic imaging and GIS software to study scenarios and determine how some of BLM's planned land management programs in the West Mojave Desert might be impacted by urban growth.

Enabling the GIS-Less

Several private and community groups are increasingly getting involved in grassroots projects aimed at protecting the ecosystem, and they pose a data distribution challenge to MDEP.

"Some of our smaller clients have little or no GIS capability at all, so we want to extend data out to them," says Foisy. "We have chosen ArcIMS as the software that will allow clients to use their Web browser to perform some basic data analysis and mapmaking functions. They won't need their own GIS tools."

MDEP is now building a new Web site around ArcIMS that will serve the satellite images and land cover layers processed in ERDAS IMAGINE directly to the Web. ArcIMS supports the ERDAS IMG file format without any conversion.

"I don't do GIS programming myself and don't have any GIS software on my computer," says Mickey Quillman, natural and cultural resources manager at the National Training Center and Fort Irwin installation. "But I will be able to pull enough information off the MDEP server to get the overview I need to make management-level decisions."

While the launch of the new ArcIMS-powered Web site is a few months away, the MDEP Web site (www.mojavedata.gov) is now using Common Gateway Interface scripts that perform simple GIS functions such as overlaying data layers or searching for land classes. MDEP integrates these scripts into ARC Macro Language routines where the queries are applied to the geospatial database and return an output product to the user via the Web.

"We believe that by serving our spatial data over the Web to virtually any level of user, we will be providing the nucleus around which present and future land management in the Mojave ecosystem can be engineered," Foisy says.

For more information about the Mojave Desert Ecosystem project, contact Jeff Foisy (tel.: 760-255-8898, e-mail: foisyj@mojavedata.gov). For more information about ERDAS' geographic imaging solutions, contact ERDAS (toll-free tel.: 1877-GO ERDAS [1-877-463-7327] or visit ERDAS on the Web at iwww.erdas.com).

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