To understand the impacts of human activities on the Mojave Desert ecosystem, scientists need information on how the ecosystem has been used in the past. Historical maps from the USGS and other sources are being scanned and georeferenced. Land use types including grazing areas, transportation routes, populated places, mining, water sources, water and power infrastructure, military forts and bases, and other structures are being digitized from historical maps and assigned attributes according to types and dates. These data can then be analyzed to determine the impacts of various types of disturbance and to study recovery times and processes.

Domestic sheep grazing near California City in the western Mojave Desert. Photo by Robert Webb, USGS.

Commercial grazing activities were phased out within the Mojave National Preserve but continue to impact the ecosystem.

This graphic illustrates the evolution of the transportation network within the Mojave National Preserve. Data such as these, derived from historical maps, are useful to desert land managers and scientists studying the Mojave Desert ecosystem.

Detail of a USGS 15' topographic map published in 1955, showing the area around the Kelso train depot, which is now in the Mojave National Preserve. Such historical maps provide valuable data, including information on roads, mining, and water sources

USGS car number W-44 was used during water source mapping in 1917. This photo of David G. Thompson (standing), and O.E. Meinzer was taken on September 5, in San Bernadino County, California, by D.G. Thompson. (USGS Photo Library Archive, File No. tdg00013)

The automobile made an early impact on the Mojave Desert ecosystem. Road maps for the region were published as early as 1915.

Viceroy Gold mine, near Mojave National Preserve. Photograph by David Miller, USGS.

Mining methods used in the Mojave Desert ecosystem include shafts, tunnels, and open pits. The Viceroy Mine, where gold has been extracted since the early 1990s, is a prime example of an open pit mine.