The MAB Program United States of America
Biosphere Reserve Information - General Description
Mojave and Colorado Deserts
General Description
This cluster biosphere
reserve is situated in south-east California and comprises four management
units: the Death Valley National Monument, Joshua Tree National Monument, the
Santa Rosa Mountains Wildlife Management Area and Anza Borrego Desert State
Park.
Death Valley, the principal feature of the biosphere reserve encompasses a
substantial percentage of the northern Mojave Desert. This combined with its
extreme altitude range (86 below to 3,368 meters above sea level) results in a
large diversity of features at the northern edge of this biogeographic region.
Rugged, sparsely vegetated mountains border a north-south oriented valley, and
are incised by numerous deep rocky canyons terminating in huge alluvial fans.
Lower and middle elevations are dominated by shrubs such as creosotebush (Larrea
divaricata), sagebrush (Atriplex spp.), mormon tea (Ephedra sp.) and blackbrush
(Coleogyne ramossissima). Trees include the Utah juniper (Juniperus osteosperma)
and one needle pine (Pinus monophylla).
Joshua Tree National monument, some 20 km east of Los Angeles, straddles the
transition area between Mojave and Colorado Deserts and is known for its Joshua
tree (Yucca brevifolia) woodlands, a typical feature of the Mojave Desert which
is higher, moister and slightly cooler. However, there are also characteristic
species of the lower Colorado Desert including Washingtonia spp.
Mining activities, the presence of large numbers of feral donkeys (Equus asinus)
and trespass grazing by cattle, off-road vehicles as well as tourism activities
are the main human influences in the region. By using the biosphere reserve
concept, it is expected that user conflicts in this multiple use area can be
solved.
Last updated: 06/27/2005