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D.V. Prose

Publications and source records attributed to D.V. Prose.

5 recordsLinked to original sources
USGS1987

Effects of substrate disturbance on secondary plant succession; Mojave Desert, California.

(1) The effects of substrate disturbance on perennial plant succession in the Mojave Desert were assessed at three military camps abandoned for 40 years. (2) Soil compaction, removal of the top layer of soil, and alteration of drainage channel density caused significant changes in perennial plant cover, density, and relative species composition. (3) Long-lived species, predominantly Larrea tridentata , were dominant in all control areas but percentage cover and density were greatly reduced in areas where substrate alterations were significant. (4) Pioneer species such as Ambrosia dumosa and Hymenoclea salsola had percentage cover values similar to or greater than controls in most areas where substrate alterations were significant, and these species were dominant in the majority of disturbed areas. (5) Where substrate alterations were insignificant in disturbed areas at one camp, Larrea was the dominant species as in the control.

Journal of Applied Ecology↗
USGS1986

Map showing areas of visible land disturbances caused by two military training operations in the Mojave Desert, California

This map shows areas that retain visible land disturbances produced during two military armored-vehicle training operations in the Mojave Desert, California. The map documents the lasting visual effects these operations have on this arid region and provides a data base for monitoring changes in the extent of visual disturbances in the future. The first training operation was initiated in April 1942, by General George S. Patton, Jr., to ready armored-vehicle divisions for desert warfare in North Africa (Meller, 1946). The Desert Training Center (DTC) encompassed 17,500 mi 2 of arid lands in California, Nevada, and Arizona, and for two years, more than one million soldiers trained under simulated battle conditions. Troops were stationed at 12 main base camps, each housing as many as 15,000 soldiers in canvas tents. From these camps, armored units would radiate into the broad valleys of the Mojave and Sonoran Deserts. Thousands of tanks, trucks, jeeps, and aircraft were used in the war games. When the DTC was inactivated in May 1944, most man-made structures were removed or buried by the U.S. Army. The second operation, called Operation Desert Strike, was held for two weeks in May 1964 (Moenk, 1964) in the same general area as the DTC. However, no temporary camps were established, and the tanks used were much larger than their World War II counterparts. Over 89,000 troops participated in this exercise. Land disturbances caused by these training exercises are still evident today throughout the designated training areas (Lathrop, 1983; Prose, 1985; Prose and Metzger, 1985). The World War II base-camp locations are easily identified because the networks of dirt roads are still used by campers, hunters, artifact seekers, and other visitors. Vehicle trails and single tracks remain on many relatively stable surfaces and are most conspicuous on surfaces composed of a veneer of stones (desert pavement).

California↗
USGS1985

Persisting effects of armored military maneuvers on some soils of the Mojave Desert

Soil compaction and substrate modification produced during large-scale armored military maneuvers in the early 1940s were examined in 1981 at seven sites in California's eastern Mojave Desert Recording penetrometer measurements show that tracks left by a single pass of an M3 "medium" tank have average soil resistance values that are 50% greater than those of the surrounding untracked soil in the upper 20 cm At one site, measurements made along short segments of track that have been visually eliminated by erosion and deposition processes show a 73% increase in penetrometer resistance over adjacent, undisturbed soils Dirt roadways at three former base camp locations could not be penetrated below 5-10 cm because of extreme compaction Soil bulk density was not as sensitive an indicator of soil compaction as was penetrometer resistance Density values in the upper 10 cm of soil are not significantly different between tank tracks and undisturbed soils at most sites, and roadways at two base camps show an average increase in bulk density of only 12% over adjacent soils. Trench excavations across tank tracks show that physical modifications of the substrate can extend vertically beneath a track to a depth of 25 cm and outward from a track's edge to 50 cm These soil disturbances are probably major factors that encourage accelerated soil erosion throughout the manuever area and also retard or prevent the return of vegetation to pre-disturbance conditions ?? 1985 Springer-Verlag New York Inc.

Environmental Geology and Water Sciences↗