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The Whole Mojave
Introduction
Although a land which is now desert, was the cradle of
civilization, man generally considers these arid regions
bleak and lifeless and seeks greener places to live. The
Spanish explorer De Anza, traveling across the southern
part of what is now California, named the region of his
ordeal, “The Land of the Dead.” Scores of grim tales of
death and bare survival characterize the history of the
California Desert.Yet, even as the sprawling Los Angeles
and San Diego metropolitan areas loom on its western
edge, there are growing numbers of people who find
behind the region’s forbidding aspect a delightful and surprising
diversity of natural forms and processes. Many
have come to feel an affection for the Desert which is, in
the words of one writer, “born of a face perceived, but
never fully seen.”
Within the area we know as the California Desert, scientists
recognize three deserts: the Mojave, the Sonoran,
and a small portion of the Great Basin. Subtropical high
pressure belts, the
“rainshadow”
effect of the coastal
mountain ranges, and other topographical features create
the conditions by which some geographers define a
desert: an area in which evaporation and transpiration
exceed the mean annual precipitation.
The California deserts were cooler and moister places
in the past. Prior to the end of the last Ice Age,
Joshua trees,
pinyon pines,
sagebrush, and
junipers
extended
across broader expanses than they do today. A subsequent
drying trend caused these plant communities to
retreat to higher elevations, leaving small enclaves of
white fir forests on mountaintops and species like the creosote
bush to dominate the lowlands. This trend toward
increasing dryness is evident in rainfall records kept since
the last century. Today, parts of the Sonora Desert receive
less water than any other place in the United States.
In addition to aridity, extreme temperatures are a trait
of the Desert. The lack of insulating humidity causes wide
fluctuations in daily seasonal temperatures varying from
14°F at Deep Springs Valley in January to nearly 117°F at
Death Valley
in July.
This harsh climate imposes several constraints on
natural processes. Desert soils, formed during the humid
past, are now often protected against erosional forces
only by natural soil crusts, called
“desert pavement,” and
what little stability that the sparse desert vegetative cover
provides. Any surface disturbance of these features
leaves the thin desert soil exposed to severe climatic
factors.
In the older deserts of the world, wind and water have
scoured features of the landscape into flat, low-relief
surfaces. In the California Desert, a variety of land forms,
including valleys,
bajadas,
pediments,
alluvial fans,
rough-hewn
mountain ranges,
washes,
sand dunes, and
dry lakebeds,
testify to its relative youth as a desert.
These land forms mix with varying soil conditions and
climatic variations to form a number of
ecosystems, in
which
desert plant and
animal
life face formidable challenges
from both the human and natural environment in
their fight for survival.
Desert organisms face a tough task to maintain water
balance. Most plants are annuals which avoid the problem
of aridity by remaining in the form of seeds until rains bring
them to life. During their short span of growth, they present
the stunning displays of
wildflowers
which are well known
in some parts of the California Desert.
Desert perennials
often use novel physiological and
anatomical adaptations to endure this hostile environment.
Some plants have “dual” root systems, with wide lateral
roots to catch surface water and deep “tap” roots to
search out underground moisture. Short-rooted succulents
store water in their stems and ration it during dry
spells. Plants like the drought-deciduous
ocotillo shed
their leaves entirely during these periods to reduce water
loss through evaporation. Some agave and yucca plants
are able to reduce water losses by taking in carbon
dioxide needed for photosynthesis at night.
Some desert animals also display these special structural
adaptations. The
desert tortoise
is able to store water
in sacs under its shell. Some desert arthropods can take
water directly from the air when the relative humidity is
over 80 percent. More often, however, the desert animal’s
adaptation is behavioral; it limits activity to the coolness of
night, dawn, or dusk. Much desert activity occurs around
seeps, springs, and other surface-water sources which,
although rare, are extremely important to the carefully balanced
natural ecosystems.
An understanding of the relationship between natural
processes and landscape cannot be complete without a
recognition of the human presence. Man is not an alien in
the environment. His structures and activities change and
become a part of the system. It is inevitable that, as population
and economic activity expand, the natural setting
and associated life forms will change. In the California
Desert a pattern of human uses has evolved from a multitude
of single-purpose venture s which reflect western
history and serve present needs.
The earliest inhabitants of the California Desert
wrought changes in the land which are still visible in many
areas. These
Native Americans,
prior to European contact
in the mid-16th century, hunted and foraged for food, set
down permanent and seasonal village sites, mined and
quarried for common and exotic stones, flood irrigated
land for agriculture, and traded goods through an elaborate
network of foot trails. Their awe and respect for natural
features and processes formed the basis for religious
practices. The native system of foot trails was of
great value to the
Spanish ,
who saw the Desert as little
more than a daunting obstacle over which they had to
travel between their settlements in Mexico and coastal
California. After acquisition of the area by the United
States in the mid-19th century, land-use intensity continually
increased.
Initial forays through the area were made by explorers,
soldiers, and Mormon settlers. Then came a growing
stream of emigrants bound for coastal California, protected
by military forts and supplied by outposts along the
route. Washington treaty makers and railroad surveyors
arrived next, and some remained in the region. In 1856,
one government surveyor staunchly defended his activities
in the region against the cries of those who claimed
the place was “not worth a red cent.” Fanning out from
the trail outposts, miners began creating colorful desert
settlements that went though boom-bust cycles until the
end of the century. By 1868, with the subduing of the
native population, most of the major modern California
Desert land uses had become entrenched in some form:
livestock grazing, mining, military bases, major transportation
arteries, and the growth of permanent settlements.
Railroad
facilities and mining operations, mainly
those for precious metals but also for the celebrated
borax trade, had substantial, although often ephemeral,
impacts. Ranchers
grazed their livestock across a wide
expanse of the Desert, at one time almost its entire western
portion.
After the turn of the century the dominance of these
activities challenged when the construction of a canal
from the
Colorado River
transformed “The Land of the
Dead” into the Imperial Valley, now one of the most
productive agricultural spots in the world. Anticipating its
destiny, the city of Los Angeles brought water across more
than 200 miles of the Desert from the
Owens Valley,
presaging
a number of large water projects.
Between two world wars, the freewheeling days of the
prospector waned as corporate entities developed large
operations. The reign of the railroads reached a national
and local zenith and then faltered as roads were laid
across the Desert. Highway settlements and resorts
sprang up to serve automobile travelers, many of whom
had been inspired by authors who had described the
Desert as a beautiful, delicate place. Foremost among
these authors was John C. Van Dyke, who wrote in the
preface to his 1901 book, The Desert: “The desert has
gone a-begging for a word of praise these many years. It
never had a sacred poet; it has in me only a lover.”
By the 1930's, this new sentiment had evolved into legislation
creating the Desert’s three large parks: Anza-
Borrego State Park and
Joshua Tree and
Death Valley
National Monuments. More water projects, notably the
Colorado River Aqueduct, brought pumping stations and
other support facilities, and the first appearance of longhigh-
voltage power transmission lines. After and absence
of many years, the military was lured back to the California
Desert sun, clear air, and sparsely settled landscape
because of the country’s new interest in flying.
As they did elsewhere in the Nation, military concerns
dramatically usurped all other activities in the California
Desert during World War II. The desert lands, however
experienced perhaps more impacts from military operations
than anywhere else in the country. Preparing for
North African tank warfare, General Patton’s troops
ranged across vast expanses of the landscape. The Army
Air Corps and the Navy withdrew large tracts of land for
training and the testing of a rapidly evolving weapons
technology.
The formation of the modern California Desert character
began immediately following the war. In 1946,
livestock grazing became more regulated under the stewardship
of the newly formed Bureau of Land Management.
The Bureau also administered such disposal policies as
the Small Tract Act of 1938, which allowed private individuals
to secure five-acre tracts for a very small fee.
Attracted by this opportunity, other land deals, and the
boon of such new technology as air conditioning, refugees
from coastal California’s urban problems spilled over into
the western fringes of the Desert. Residential developments
ranged from the closely spaced suburbia of Palm
Springs to “jackrabbit homesteads,” shacks measuring 20
feet on each side and dispersed sparsely across hundreds
of square miles. The war’s legacy of jeeps and aircooled
engines allowed visitors to penetrate even the
most remote regions of the Desert, while cheap gas and
improved roads made auto touring increasingly popular.
Mineral operations increased in size, but not generally in
number.
Today, the physical manifestations of these human
pressures have become evident across the entire desert
landscape: over 100 communities, ranging in type from
one-person mining settlements to resorts: large industrial
mining operations and thousands of speculative digs;
canal-fed agricultural valleys; nine military bases and testing
groungs; 1.1 electrical power generating plants; 3,500
miles of high-capacity power transmission lines; 12,000
miles of oil and gas pipelines; over 100 communication
sites on ridges and mountaintops; 15,000 miles of paved
and maintained roads; and thousands more miles of roads
and ways cut solely by motorized vehicles.
Adapted from;
INTRODUCTION the California Desert CONSERVATION AREA PLAN IN PERSPECTIVE
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Overview

Great Basin Desert

Mojave Desert
AbeBooks Search

Sonoran (Colorado) Desert

Pinon pine acts as nurse to Joshua trees

El Mirage Dry Lakebed

Desert perennials
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