Mono Lake is a large, shallow saline soda lake in Mono County, formed at least 760,000 years ago as a terminal lake in an endorheic basin. The lack of an outlet causes high levels of salts to accumulate in the lake; these salts make the lake water alkaline. This desert lake has an unusually productive ecosystem based on brine shrimp that thrive in its waters, provides critical habitat for two million annual migratory birds that feed on the shrimp and alkali flies; the native Kutzadika'a people derived nutrition from the Ephydra hians pupae, which live in the shallow waters around the edge of the lake. When the city of Los Angeles diverted water from the freshwater streams flowing into the lake, it lowered the lake level, which imperiled the migratory birds; the Mono Lake Committee formed in response and won a legal battle that forced Los Angeles to replenish the lake level. Mono Lake occupies part of an endorheic basin that has no outlet to the ocean. Dissolved salts in the runoff thus remain in the lake and raise the water's pH levels and salt concentration.
The tributaries of Mono Lake include Lee Vining Creek, Rush Creek and Mill Creek which flows through Lundy Canyon. The basin was formed by geological forces over the last five million years: basin and range crustal stretching and associated volcanism and faulting at the base of the Sierra Nevada. Five million years ago, the Sierra Nevada was an eroded set of rolling hills and Mono Basin and Owens Valley did not yet exist. From 4.5 to 2.6 million years ago, large volumes of basalt were extruded around what is now Cowtrack Mountain. Volcanism in the area occurred 3.8 million to 250,000 years ago. This activity was northwest of Mono Basin and included the formation of Aurora Crater, Beauty Peak, Cedar Hill, Mount Hicks. Mono Lake is believed to have formed at least 760,000 years ago, dating back to the Long Valley eruption. Sediments located below the ash layer hint that Mono Lake could be a remnant of a larger and older lake that once covered a large part of Nevada and Utah, which would put it among the oldest lakes in North America.
At its height during the most recent ice age, the lake would have been about 900 feet deep. Prominent old shore lines, called strandlines by geologists, can be seen west of the Lake. Mono Lake is in a geologically active area at the north end of the Mono–Inyo Craters volcanic chain and is close to Long Valley Caldera. Volcanic activity continues in the Mono Lake vicinity: the most recent eruption occurred 350 years ago, resulting in the formation of Paoha Island. Panum Crater is an excellent example of a combined rhyolite cinder cone. Among the most iconic features of Mono Lake are the columns of limestone that tower over the water surface; these limestone towers consist of calcium carbonate minerals such as calcite. This type of limestone rock is referred to as tufa, a term used for limestone that forms in low to moderate temperatures. Mono Lake is a alkaline lake, or soda lake. Alkalinity is a measure of how many bases are in a solution, how well the solution can neutralize acids. Carbonate and bicarbonate are both bases.
Hence, Mono Lake has a high content of dissolved inorganic carbon. Through supply of calcium ions, the water will precipitate carbonate-minerals such as calcite. Subsurface waters enter the bottom of Mono Lake through small springs. High concentrations of dissolved calcium ions in these subsurface waters cause huge amounts of calcite to precipitate around the spring orifices; the tufa formed at the bottom of the lake. It took many decades or centuries to form the well-recognized tufa towers; when lake levels fell, the tufa towers came to rise above the water surface and stand as the majestic pillars seen today. Description of the Mono Lake tufa dates back to the 1880s, when Edward S. Dana and Israel C. Russell made the first systematic descriptions of the Mono Lake tufa; the tufa occurs as "modern" tufa towers. However, you can find tufa sections from old shorelines, when the lake levels were higher; these pioneering works in tufa morphology are still referred to by researchers today and were confirmed by James R. Dunn in 1953.
The tufa types can be divided into three main categories based on morphology:Lithoid tufa - massive and porous with a rock-like appearance Dendritic tufa - branching structures that look similar to small shrubs Thinolitic tufa - large well-formed crystals of several centimetersThese tufa types vary interchangeably both between individual tufa towers but within individual tufa towers. There can be multiple transitions between tufa morphologies within a single tufa tower. Through time, many hypotheses were developed regarding the formation of the large thinolite crystals in thinolitic tufa, it was clear that the thinolites represented a calcite pseudomorph after some unknown original crystal. However, the original crystal was only determined when the mineral ikaite was discovered in 1963. Ikaite, or hexahydrated CaCO3, is only crystallizes at near-freezing temperatures, it is believed that calcite crystallization inhibitors such as phosphate and organic carbon may aid in the stabilization of ikaite.
When heated, ikaite becomes replaced by smaller crystals of calcite. In the Ikka Fjord of Greenland, ikaite was observed to grow in columns similar to the tufa towers of Mono Lake; this has led scienti
Los Angeles Aqueduct
The Los Angeles Aqueduct system, comprising the Los Angeles Aqueduct and the Second Los Angeles Aqueduct, is a water conveyance system and operated by the Los Angeles Department of Water and Power. The Owens Valley aqueduct was designed and built by the city's water department, at the time named The Bureau of Los Angeles Aqueduct, under the supervision of the department's Chief Engineer William Mulholland; the system delivers water from the Owens River in the Eastern Sierra Nevada Mountains to Los Angeles, California. In 1971 it was recognized by the American Society of Civil Engineers on the List of Historic Civil Engineering Landmarks, its construction was controversial from the start, as water diversions to Los Angeles all but ended agriculture in the Owens Valley. Since its continued operation has led to public debate and court battles over the environmental impacts of the aqueduct on Mono Lake and other ecosystems; the aqueduct project began in 1905 when the voters of Los Angeles approved a US$1.5 million bond for the'purchase of lands and water and the inauguration of work on the aqueduct'.
On June 12, 1907 a second bond was passed with a budget of US$24.5 million to fund construction. Construction was divided into 11 divisions and a cement plant; the number of men who were on the payroll the first year was 2,629 and this number peaked at 6,060 in May 1909. In 1910, employment dropped to 1,150 due to financial reasons but rebounded in the year. Between 1911 and 1912 employment ranged from 2,800 to 3,800 workers; the number of laborers working on the aqueduct at its peak was 3,900. In 1913 the City of Los Angeles completed construction of the first Los Angeles Aqueduct; the aqueduct as constructed consisted of six storage reservoirs and 215 mi of conduit. Beginning three and one half miles north of Black Rock Springs, the aqueduct diverts the Owens River into an unlined canal to begin its 233 mi journey south to the Lower San Fernando Reservoir; this reservoir was renamed the Lower Van Norman Reservoir. The original project consisted of 24 mi of open unlined canal, 37 mi of lined open canal, 97 mi of covered concrete conduit, 43 mi of concrete tunnels, 12.00 mi steel siphons, 120 mi of railroad track, two hydroelectric plants, three cement plants, 170 mi of power lines, 240 mi of telephone line, 500 mi of roads and was expanded with the construction of the Mono Extension and the Second Los Angeles Aqueduct.
The aqueduct uses gravity alone to move the water and uses the water to generate electricity, which makes it cost-efficient to operate. The aqueduct system is still in operation; the construction of the Los Angeles Aqueduct eliminated the Owens Valley as a viable farming community and devastated the Owens Lake ecosystem. A group labeled the "San Fernando Syndicate" – including Fred Eaton, Harrison Otis, Henry Huntington, other wealthy individuals – were a group of investors who bought land in the San Fernando Valley based on inside knowledge that the Los Angeles aqueduct would soon irrigate it and encourage development. Although there is disagreement over the actions of the "syndicate" as to whether they were a "diabolical" cabal or only a group that united the Los Angeles business community behind supporting the aqueduct, Eaton and others connected with the project have long been accused of using deceptive tactics and underhanded methods to obtain water rights and block the Bureau of Reclamation from building water infrastructure for the residents in Owens Valley.
By the 1920s, the aggressive pursuits of the water rights and the diversion of the Owens River precipitated the outbreak of violence known as the California Water Wars. Farmers in Owens Valley attacked infrastructure, dynamiting the aqueduct numerous times and opening sluice gates to divert the flow of water; the aqueduct's water provided developers with the resources to develop the San Fernando Valley and Los Angeles through World War II. Mulholland's role in the vision and completion of the aqueduct and the growth of Los Angeles into a large metropolis is recognized and well-documented; the William Mulholland Memorial Fountain, built in 1940 and located at Riverside Drive and Los Feliz Blvd. in Los Feliz, is dedicated to his memory and contributions. Mulholland Drive and Mulholland Dam are both named for him as well. In an effort to find more water, the city of Los Angeles reached farther north. In 1930, Los Angeles voters passed a third US$38.8 million bond to buy land in the Mono Basin and fund the Mono Basin extension.
The 105 mile extension diverted flows from the Rush Creek, Lee Vining Creek and Parker Creeks that would have flowed into Mono Lake. The construction of the Mono extension consisted of an intake at Lee Vining Creek, the Lee Vining conduit to the Grant Reservoir on Rush Creek, which would have a capacity of 48,000 acre⋅ft, the 12.7 mile Mono Craters Tunnel to the Owens River and a second reservoir named Crowley Lake with a capacity of 183,465 acre⋅ft in Long Valley at the head of the Owens River Gorge. Completed in 1940, diversions began in 1941; the Mono Extension has a design capacity of 400 cu ft/s of flow to the aqueduct however the flow was limited to 123 cu ft/s due to the limited downstream capacity of the Los Angeles Aqueduct. Full appropriation of the water could not be met until the second aqueduct was completed in 1970. Between 1940 and 1970, water exports through the Mono Extension averaged 57
New Mexico is a state in the Southwestern region of the United States of America. It is one of the Mountain States and shares the Four Corners region with Utah and Arizona. With a population around two million, New Mexico is the 36th state by population. With a total area of 121,592 sq mi, it is the fifth-largest and sixth-least densely populated of the 50 states. Due to their geographic locations and eastern New Mexico exhibit a colder, alpine climate, while western and southern New Mexico exhibit a warmer, arid climate; the economy of New Mexico is dependent on oil drilling, mineral extraction, dryland farming, cattle ranching, lumber milling, retail trade. As of 2016–2017, its total gross domestic product was $95 billion with a GDP per capita of $45,465. New Mexico's status as a tax haven yields low to moderate personal income taxes on residents and military personnel, gives tax credits and exemptions to favorable industries; because of this, its film industry contributed $1.23 billion to its overall economy.
Due to its large area and economic climate, New Mexico has a large U. S. military presence marked notably with the White Sands Missile Range. Various U. S. national security agencies base their research and testing arms in New Mexico such as the Sandia and Los Alamos National Laboratories. During the 1940s, Project Y of the Manhattan Project developed and built the country's first atomic bomb and nuclear test, Trinity. Inhabited by Native Americans for many thousands of years before European exploration, it was colonized by the Spanish in 1598 as part of the Imperial Spanish viceroyalty of New Spain. In 1563, it was named Nuevo México after the Aztec Valley of Mexico by Spanish settlers, more than 250 years before the establishment and naming of the present-day country of Mexico. After Mexican independence in 1824, New Mexico became a Mexican territory with considerable autonomy; this autonomy was threatened, however, by the centralizing tendencies of the Mexican government from the 1830s onward, with rising tensions leading to the Revolt of 1837.
At the same time, the region became more economically dependent on the United States. At the conclusion of the Mexican–American War in 1848, the United States annexed New Mexico as the U. S. New Mexico Territory, it was admitted to the Union as the 47th state on January 6, 1912. Its history has given New Mexico the highest percentage of Hispanic and Latino Americans, the second-highest percentage of Native Americans as a population proportion. New Mexico is home to part of the Navajo Nation, 19 federally recognized Pueblo communities of Puebloan peoples, three different federally recognized Apache tribes. In prehistoric times, the area was home to Ancestral Puebloans and the modern extant Comanche and Utes inhabited the state; the largest Hispanic and Latino groups represented include the Hispanos of New Mexico and Mexican Americans. The flag of New Mexico features the state's Spanish origins with the same scarlet and gold coloration as Spain's Cross of Burgundy, along with the ancient sun symbol of the Zia, a Puebloan tribe.
These indigenous, Mexican and American frontier roots are reflected in the eponymous New Mexican cuisine and the New Mexico music genre. New Mexico received its name long before the present-day nation of Mexico won independence from Spain and adopted that name in 1821. Though the name “Mexico” itself derives from Nahuatl, in that language it referred to the heartland of the Empire of the Mexicas in the Valley of Mexico far from the area of New Mexico, Spanish explorers used the term “Mexico” to name the region of New Mexico in 1563. In 1581, the Chamuscado and Rodríguez Expedition named the region north of the Rio Grande "San Felipe del Nuevo México"; the Spaniards had hoped to find wealthy indigenous Mexica cultures there similar to those of the Aztec Empire of the Valley of Mexico. The indigenous cultures of New Mexico, proved to be unrelated to the Mexicas, they were not wealthy, but the name persisted. Before statehood, the name "New Mexico" was applied to various configurations of the U.
S. territory, to a Mexican state, to a province of New Spain, all in the same general area, but of varying extensions. With a total area of 121,699 square miles, the state is the fifth-largest state of the US, larger than British Isles. New Mexico's eastern border lies along 103°W longitude with the state of Oklahoma, 2.2 miles west of 103°W longitude with Texas. On the southern border, Texas makes up the eastern two-thirds, while the Mexican states of Chihuahua and Sonora make up the western third, with Chihuahua making up about 90% of that; the western border with Arizona runs along the 109° 03'W longitude. The southwestern corner of the state is known as the Bootheel; the 37°N parallel forms the northern boundary with Colorado. The states of New Mexico, Colorado and Utah come together at the Four Corners in New Mexico's northwestern corner. New Mexico has no natural water sources
Parker Dam is a concrete arch-gravity dam that crosses the Colorado River 155 miles downstream of Hoover Dam. Built between 1934 and 1938 by the Bureau of Reclamation, it is 320 feet high, 235 feet of which are below the riverbed, making it the deepest dam in the world; the dam's primary functions are to create a reservoir, to generate hydroelectric power. The reservoir behind the dam is called Lake Havasu and can store 647,000 acre⋅ft or over 210 billion US gallons; the dam straddles the state border at the narrows the river passes through between the Whipple Mountains of California and the Buckskin Mountains of Arizona. The power plant has four Francis turbines with a combined capacity of 120 MW; each turbine weighs 60,000 pounds. The head is 72 feet, it produces electricity at 97 percent efficiency. Half of the electricity the plant produces is used by the Metropolitan Water District to pump water along the Colorado River Aqueduct, the rest is sold to utilities in California and Nevada; the generation of power is limited by a requirement to keep the water level of Lake Havasu between 440 and 450 feet for proper operation of pumping plants for the Central Arizona Project and the Colorado River Aqueduct.
Lake Havasu is the water source for the Colorado River Aqueduct. The aqueduct is operated by the Metropolitan Water District of Southern California, which supplies water to all cities in the greater Los Angeles, San Bernardino, San Diego areas; the district paid for nearly the entire cost of the dam, but it is owned and operated by the U. S. Bureau of Reclamation. Lake Havasu is the water source for the Central Arizona Project Aqueduct; the project is designed to provide water for irrigated agricultural areas, as well as municipal water for several Arizona communities, including the metropolitan areas of Phoenix and Tucson. Construction of the dam was a contentious issue for Arizona. Built as part of the larger Colorado River Compact of 1922, several political groups, their members and owned utility companies in Arizona were not pleased with the plan in general and refused to sign it until 1944. Arizona continued to dispute its water allotments until a 1963 Supreme Court decision settled the issue.
The court has had to adjust the agreement several times since, most in 2000. As as 2008 Arizona Senator John McCain called for a renegotiation of the plan. In 1935, when Arizona Governor Benjamin Baker Moeur sent 6 members of the Arizona National Guard to observe the dam's construction, they reported back that there was construction activity on the Arizona side of the river. Arizona Attorney General Arthur La Prade concluded that the Metropolitan Water District had no right to build on Arizona's territory, which prompted Governor Moeur to send a larger National Guard force to halt construction; the troops were recalled when Secretary of the Interior Harold L. Ickes halted construction until the issue had been settled; the Department of the Interior took Arizona to court over the issue hoping to end the state's interference. To the Department of the Interior's shock, the Supreme Court sided with Arizona and dismissed the injunction; the court concluded that the dam had never been directly approved by Congress and that California was not entitled to build on Arizona's land without Arizona's consent.
Arizona agreed to allow the dam in exchange for approval of the Gila River irrigation project. List of dams and reservoirs in California List of largest reservoirs of California List of power stations in California List of the tallest dams in United States List of United States Bureau of Reclamation dams USBR - Parker-Davis Project USGS - Real-time water data for Colorado River below Parker Dam Profile on desertusa.com Historic American Engineering Record No. AZ-54, "Parker Dam, Spanning Colorado River between AZ & CA, Parker, La Paz County, AZ"
William Mulholland was an Irish American civil engineer, responsible for building the infrastructure to provide a water supply that allowed Los Angeles to grow into the largest city in California. As the head of a predecessor to the Los Angeles Department of Water and Power, Mulholland designed and supervised the building of the Los Angeles Aqueduct, a 233-mile -long system to move water from Owens Valley to the San Fernando Valley; the creation and operation of the aqueduct led to the disputes known as the California Water Wars. In March 1928, Mulholland's career came to an end when the St. Francis Dam failed just over 12 hours after he and his assistant gave it a safety inspection. William Mulholland was born in Belfast, part of the United Kingdom, his parents Hugh and Ellen Mulholland were Dubliners and they returned to the city a few years after William's birth. His younger brother, Hugh Jr. was born in 1856. At the time of Mulholland's birth, his father was working as a guard for the Royal Mail.
In 1862, when William was seven years old, his mother died. Three years his father remarried. William was educated at O'Connell School by the Christian Brothers in Dublin. After having been beaten by his father for receiving bad marks in school, Mulholland ran off to sea. At 15, Mulholland was a member of the British Merchant Navy, he spent the next four years as a seaman on the Gleniffer, making at least 19 Atlantic crossings to ports in North America and the Caribbean. In 1874 he disembarked in New York and headed west to Michigan where he worked a summer on a Great Lakes freighter and the winter in a lumber camp. After nearly losing a leg in a logging accident he moved to Ohio. Mulholland reconnected with his brother Hugh, in December 1876 they stowed away on a ship in New York bound for California, they were forced to leave the ship. They walked over 47 miles through jungle to the city of Balboa. Mulholland arrived in Los Angeles in 1877. After arriving in Los Angeles, which at the time had a population of about 9,000, Mulholland decided to return to life at sea, as work was hard to find.
On his way to the port at San Pedro to find a ship, he accepted a job digging a well. After a brief stint in Arizona where he prospected for gold and worked on the Colorado River, he obtained a job from Frederick Eaton as Deputy Zanjero with the newly formed Los Angeles City Water Company. In Alta California during the Spanish and Mexican administrations, water was delivered to Pueblo de Los Angeles in a large open ditch, the Zanja Madre; the man who tended the ditch was known as a zanjero. In 1880, Mulholland oversaw the laying of the first iron water pipeline in Los Angeles. Mulholland left the employment of the LACWC in 1884 but returned in mid-December of that same year, he worked for the Sespe Land and Water Company. As part of his compensation he was granted twenty acres on Sespe Creek. In 1886 he returned to the LAWC and, in October of that year, became a naturalized American citizen. At the end of that year he was made the superintendent of the LACWC. In 1898, the Los Angeles city government decided not to renew the contract with the LACWC.
Four years the Los Angeles Water Department was established with Mulholland as its superintendent. In 1911, the Water Department was renamed the Bureau of Water Works and Supply with Mulholland named as its chief engineer. In 1937, two years after Mulholland's death, the Bureau of Water Works and Supply merged with the Bureau of Power and Light to form the Los Angeles Department of Water and Power. Mulholland had a vision of a Los Angeles that would become far bigger than the Los Angeles of the start of the 20th century; the limiting factor to the growth of Los Angeles was its water supply, because it has a semi-arid climate with unreliable rainfall. "If you don't get the water, you won't need it," Mulholland famously remarked. Mulholland shared the vision of a much larger Los Angeles with Frederick Eaton, the mayor of Los Angeles from 1898 through 1900, they both worked together in the private Los Angeles Water Company in the 1880s. In 1886, Eaton became City Mulholland became superintendent of the Water Company.
When Eaton was elected mayor of Los Angeles, he was instrumental in converting the Water Company to city control in 1902. When the company became the Los Angeles Water Department, Mulholland continued to be superintendent, due to his vast knowledge of the water system. Expansion followed as Mulholland's public works program began to irrigate large areas of arid land. Within a decade, the city's population had doubled from just 50,000 in 1890 to more than 100,000 in 1900. Ten years it had tripled to 320,000. To create this expansion and Mulholland realized that the large amount of runoff from the Sierra Nevada in Owens Valley could be delivered to Los Angeles through a gravity-fed aqueduct. From 1902 through 1905, Eaton and others engaged in underhanded methods to ensure that Los Angeles would gain the water rights in the Owens Valley, blocking the Bureau of Reclamation from building water infrastructure for the residents in Owens Valley. While Eaton engaged in most of the political maneuvrings and chicanery, Mulholland misled Los Angeles public opinion by understating the amount of water available for Los Angeles' growth.
Mulholland misled residents of the Owens Valley: he indicated that Los Angeles would only use unused flows in the Owens Valley, while planning on using the full water rights to fill the aquifer of the San Fernando Valley. In 1906, the
California's Colorado Desert is a part of the larger Sonoran Desert. It encompasses 7 million acres, including the irrigated Coachella and Imperial valleys, it is home to fauna. The Colorado Desert is a subdivision of the larger Sonoran Desert encompassing 7 million acres; the desert encompasses Imperial County and includes parts of San Diego County, Riverside County, a small part of San Bernardino County. Most of the Colorado Desert lies at a low elevation, below 1,000 feet, with the lowest point of the desert floor at 275 feet below sea level, at the Salton Sea. Although the highest peaks of the Peninsular Ranges reach elevations of nearly 10,000 feet, most of the region's mountains do not exceed 3,000 feet. In this region, the geology is dominated by the transition of the tectonic plate boundary from rift to fault; the southernmost strands of the San Andreas Fault connect to the northernmost extensions of the East Pacific Rise. The region is subject to earthquakes, the crust is being stretched, which will result in a sinking of the terrain over time.
The Colorado Desert's climate distinguishes it from other deserts. The region experiences greater summer daytime temperatures than higher-elevation deserts and never experiences frost. In addition, the Colorado Desert experiences two rainy seasons per year toward the southern portion of the region; the west coast Peninsular Ranges, or other west ranges, of Southern California–northern Baja California, block most eastern Pacific coastal air and rains, producing an arid climate. Other short or longer-term weather events can move in from the Gulf of California to the south, are active in the summer monsoons; these include remnants of Pacific hurricanes, storms from the southern tropical jetstream, the northern intertropical convergence zone. The region's terrestrial habitats include creosote bush scrub. Higher elevations are dominated by pinyon pine and California juniper, with areas of manzanita and Coulter pine. In addition to hardy perennials, more than half of the desert's plant species are herbaceous annuals, appropriately timed winter rains produce abundant early spring wildflowers.
In the southern portion of the region, the additional moisture supplied by summer rainfall fosters the germination of summer annual plants and supports smoketree and palo verde trees. Common desert wildlife include mule deer, desert kangaroo rat, cactus mouse, black-tailed jackrabbit, Gambel's quail, red-diamond rattlesnake. Among sensitive species are flat-tailed horned lizard, Coachella Valley fringe-toed lizard, desert tortoise, prairie falcon, Andrews' dune scarab beetle, peninsular bighorn sheep, California leaf-nosed bat; the best place to spot wildlife is at the wetland refuges along the Colorado River, Cibola National Wildlife Refuge and Imperial National Wildlife Refuge. In the Colorado Desert's arid environment and wetland habitats are limited in extent but are critically important to wildlife. Runoff from seasonal rains and groundwater springs forms desert arroyos, desert fan palm oases, freshwater marshes, brine lakes, desert washes and perennial streams, desert riparian vegetation communities dominated by cottonwood and non-native tamarisk.
Two of the region's most significant aquatic systems are the Colorado River. While most desert wildlife depend on aquatic habitats as water sources, a number of species, such as the arroyo toad, desert pupfish, Yuma rail, southwestern willow flycatcher, are restricted to these habitats. In some places, summer rains produce short-lived seasonal pools that host uncommon species like Couch's spadefoot toad. Desert fan palm oases are rare, they occur only where permanent water sources are available, such as at springs or along fault lines, where groundwater is forced to the surface by the movement of hard impermeable rock, can be found in the San Jacinto, Santa Rosa, Little San Bernardino mountains, in the canyons of Anza-Borrego Desert State Park, along the San Andreas Fault in the Coachella Valley. The only palm native to California, Washingtonia filifera, grows at the oases; some sub-regions of the Colorado Desert contain endemic flora. Along the Lower Colorado River Valley, in-flow side canyons, flatlands, or low-to-higher level elevations, at least three such flora occur: Hesperocallis undulata, Nolina bigelovii, Peucephyllum schottii.
Joshua Tree National Park Imperial NWR Sonny Bono Salton Sea NWR Indio Hills Palms Anza-Borrego Desert State Park Ocotillo Wells State Vehicular Recreation Area Picacho State Recreation Area Heber Dunes State Vehicular Recreation Area Salton Sea State Recreation Area The Colorado Desert is one of the least-populous regions in California, but human activities have had substantial impacts on the region's habitats and wildlife. Many unique communities aquatic and dune systems, are limited in distribution and separated by vast expanses of inhospitable, arid desert terrain. Limited human disturbances can have markedly deleterious effects on the endemic and sensitive species supported by these unique regional systems; some of the greatest human-caused effects on the region have resulted from the water diversions and flood control measures along the Colorado River. These measures have altered the region's hydrology by redistributing the region's water supp
San Bernardino County, California
San Bernardino County the County of San Bernardino, is a county located in the southern portion of the U. S. state of California, is located within the Greater Los Angeles area. As of the 2010 U. S. Census, the population was 2,035,210, making it the fifth-most populous county in California, the 12th-most populous in the United States; the county seat is San Bernardino. While included within the Greater Los Angeles area, San Bernardino County is included in the Riverside–San Bernardino–Ontario metropolitan statistical area, as well as the Los Angeles–Long Beach combined statistical area. With an area of 20,105 square miles, San Bernardino County is the largest county in the United States by area, although some of Alaska's boroughs and census areas are larger; the county is close to the size of West Virginia. It is larger than each of the nine smallest states, larger than the four smallest states combined, larger than 70 sovereign nations; this vast county stretches from where the bulk of the county population resides (in two Census County Divisions, holding 1,422,745 people as of the 2010 Census, covering the 450 square miles, across the thinly populated deserts and mountains.
It spans an area from south of the San Bernardino Mountains in San Bernardino Valley, to the Nevada border and the Colorado River. Spanish Missionaries from Mission San Gabriel Arcángel established a church at the village of Politania in 1810. Father Francisco Dumetz named the church San Bernardino on May 20, 1810, after the feast day of St. Bernardino of Siena; the Franciscans gave the name San Bernardino to the snowcapped peak in Southern California, in honor of the saint and it is from him that the county derives its name. In 1819, they established the San Bernardino de Sena Estancia, a mission farm in what is now Redlands. Following Mexican independence from Spain in 1821, Mexican citizens were granted land grants to establish ranchos in the area of the county. Rancho Jurupa in 1838, Rancho Cucamonga and El Rincon in 1839, Rancho Santa Ana del Chino in 1841, Rancho San Bernardino in 1842 and Rancho Muscupiabe in 1844. Agua Mansa was the first town in what became San Bernardino County, settled by immigrants from New Mexico on land donated from the Rancho Jurupa in 1841.
Following the purchase of Rancho San Bernardino, the establishment of the town of San Bernardino in 1851 by Mormon colonists, San Bernardino County was formed in 1853 from parts of Los Angeles County. Some of the southern parts of the county's territory were given to Riverside County in 1893. According to the U. S. Census Bureau, the county has a total area of 20,105 square miles, of which 20,057 square miles is land and 48 square miles is water, it is the largest county by the largest in the United States. It is larger than the states of New Jersey, Connecticut and Rhode Island combined, it borders both Arizona. The bulk of the population two million, live in the 480 square miles south of the San Bernardino Mountains adjacent to Riverside and in the San Bernardino Valley. Over 300,000 others live just north of the San Bernardino Mountains, agglomerating around Victorville covering 280 square miles in Victor Valley, adjacent to Los Angeles County. Another 100,000 people live scattered across the rest of the sprawling county.
The Mojave National Preserve covers some of the eastern desert between Interstate 15 and Interstate 40. The desert portion includes the cities of Needles next to the Colorado River and Barstow at the junction in Interstate 15 and Interstate 40. Trona is at the northwestern part of the county west of Death Valley; this national park within Inyo County has a small portion of land within the San Bernardino County. The largest metropolitan area in the Mojave Desert part of the county is Victor Valley, with the incorporated localities of Adelanto, Apple Valley and Victorville. Further south, a portion of Joshua Tree National Park overlaps the county near the High Desert area, in the vicinity of Twentynine Palms; the remaining towns make up the remainder of the High Desert: Pioneertown, Yucca Valley, Joshua Tree and Morongo Valley. The mountains are home to the San Bernardino National Forest, include the communities of Crestline, Lake Arrowhead, Running Springs, Big Bear City, Forest Falls, Big Bear Lake.
The San Bernardino Valley is at the eastern end of the San Gabriel Valley. The San Bernardino Valley includes the cities of Ontario, Chino Hills, Fontana, Colton, Grand Terrace, Rancho Cucamonga, San Bernardino, Loma Linda, Highland and Yucaipa. Angeles National Forest Death Valley National Park Havasu National Wildlife Refuge Joshua Tree National Park Mojave National Preserve San Bernardino National Forest There are at least 35 official wilderness areas in the county that are part of the National Wilderness Preservation System; this is the largest number of any county in the United States. The majority are managed by the Bureau of Land Management, but some are integral components of the above listed national protected areas. Most of these wilderness areas lie within the county, but a few are shared with neighboring counties. Except as noted, these wilderness areas are managed by the Bureau of Land Management and lie within San Bernardino County: The 2010 United States Census reported that San Bernardino County had a population of 2,035,210.
The racial makeup of San Bernardino County was 1,153,16