1.
Nevada
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Nevada is a state in the Western, Mountain West, and Southwestern regions of the United States of America. Nevada is the 7th most extensive, the 34th most populous, nearly three-quarters of Nevadas people live in Clark County, which contains the Las Vegas–Paradise metropolitan area where three of the states four largest incorporated cities are located. Nevada is officially known as the Silver State because of the importance of silver to its history and economy. It is also known as the Battle Born State, because it achieved statehood during the Civil War, as the Sage-brush State, for the plant of the same name. Nevada borders Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, Nevada is largely desert and semi-arid, much of it located within the Great Basin. Areas south of the Great Basin are located within the Mojave Desert, while Lake Tahoe, about 86% of the states land is managed by various jurisdictions of the U. S. federal government, both civilian and military. Before European contact, Native Americans of the Paiute, Shoshone, the first Europeans to explore the region were Spanish. They called the region Nevada because of the snow covered the mountains in winter. The area formed part of the Viceroyalty of New Spain, the United States annexed the area in 1848 after its victory in the Mexican–American War, and it was incorporated as part of Utah Territory in 1850. The discovery of silver at the Comstock Lode in 1859 led to a boom that became an impetus to the creation of Nevada Territory out of western Utah Territory in 1861. Nevada became the 36th state on October 31,1864, as the second of two added to the Union during the Civil War. Nevada has a reputation for its libertarian laws, in 1940, with a population of just over 110,000 people, Nevada was by far the least-populated state, with less than half the population of the next least-populated state. However, legalized gambling and lenient marriage and divorce laws transformed Nevada into a major tourist destination in the 20th century, Nevada is the only U. S. state where prostitution is legal, though it is illegal in Clark County, Washoe County and Carson City. The tourism industry remains Nevadas largest employer, with mining continuing as a sector of the economy. The name Nevada comes from the Spanish nevada, meaning snow-covered, most Nevadans pronounce the second syllable of their state name using the vowel of trap. Many from outside the Western United States pronounce it with the vowel of father, although the latter pronunciation is closer to the Spanish pronunciation, it is not the pronunciation preferred by most Nevadans. State Assemblyman Harry Mortenson proposed a bill to recognize the alternate pronunciation of Nevada, though the bill was not supported by most legislators, the Nevadan pronunciation is the de facto official one, since it is the one used by the state legislature. Nevada is almost entirely within the Basin and Range Province, and is broken up by many mountain ranges
2.
Utah
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Utah is a state in the western United States. It became the 45th state admitted to the U. S. on January 4,1896, Utah is the 13th-largest by area, 31st-most-populous, and 10th-least-densely populated of the 50 United States. Utah has a population of more than 3 million, approximately 80% of whom live along the Wasatch Front, Utah is bordered by Colorado to the east, Wyoming to the northeast, Idaho to the north, Arizona to the south, and Nevada to the west. It also touches a corner of New Mexico in the southeast, approximately 62% of Utahns are reported to be members of The Church of Jesus Christ of Latter-day Saints or LDS, which greatly influences Utahn culture and daily life. The LDS Churchs world headquarters is located in Salt Lake City, Utah is the only state with a majority population belonging to a single church. The state is a center of transportation, education, information technology and research, government services, mining, in 2013, the U. S. Census Bureau estimated that Utah had the second fastest-growing population of any state. St. George was the metropolitan area in the United States from 2000 to 2005. Utah also has the 14th highest median income and the least income inequality of any U. S. state. A2012 Gallup national survey found Utah overall to be the best state to live in based on 13 forward-looking measurements including various economic, lifestyle, the name Utah is derived from the name of the Ute tribe. It means people of the mountains in the Ute language, according to other sources Utah is derived from the Apache name Yudah which means Tall. These Native American tribes are subgroups of the Ute-Aztec Native American ethnicity and were sedentary, the Ancestral Pueblo people built their homes through excavations in mountains, and the Fremont people built houses of straw before disappearing from the region around the 15th century. Another group of Native Americans, the Navajo, settled in the region around the 18th century, in the mid-18th century, other Uto-Aztecan tribes, including the Goshute, the Paiute, the Shoshone, and the Ute people, also settled in the region. These five groups were present when the first European explorers arrived, the southern Utah region was explored by the Spanish in 1540, led by Francisco Vásquez de Coronado, while looking for the legendary Cíbola. A group led by two Catholic priests—sometimes called the Dominguez-Escalante Expedition—left Santa Fe in 1776, hoping to find a route to the coast of California, the expedition traveled as far north as Utah Lake and encountered the native residents. The Spanish made further explorations in the region, but were not interested in colonizing the area because of its desert nature, in 1821, the year Mexico achieved its independence from Spain, the region became known as part of its territory of Alta California. European trappers and fur traders explored some areas of Utah in the early 19th century from Canada, the city of Provo, Utah was named for one, Étienne Provost, who visited the area in 1825. The city of Ogden, Utah was named after Peter Skene Ogden, in late 1824, Jim Bridger became the first known English-speaking person to sight the Great Salt Lake. Due to the salinity of its waters, Bridger thought he had found the Pacific Ocean
3.
Snake Range
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The Snake Range is a mountain range in White Pine County, Nevada, United States. The south-central portion of the range is included within Great Basin National Park, the range reaches a maximum elevation of 13,065 feet at the summit of Wheeler Peak, the tallest independent mountain within Nevada and the second highest point within the state. The range also contains four of the five highest mountain peaks in Nevada, typical of other ranges in the Basin and Range Province, the Snake Range runs in a north-south direction, for approximately 60 miles. To the west are Spring Valley and the Schell Creek Range, and to the east across the Utah border are Snake Valley, Sacramento Pass is where U. S. Route 6-50, the Loneliest Highway in America, crosses the range. It is the means of eastbound access to this part of eastern Nevada. Great Basin National Park is located in the section of the Snake Range. Established in 1986, it protects the unique geologic and habitat features of the range and Great Basin Desert. The southern section includes the natural rock Lexington Arch. Several large groves of ancient Great Basin Bristlecone Pine trees thrive in the Great Basin montane forests of the higher elevations. The higher elevations of the Snake Range in the section are protected by the Mount Moriah Wilderness Area. The Snake Range includes two groups of peaks, the southern section rises quickly from a point near the border with Lincoln County, reaching the summit of Granite Peak just 10 miles to the north. From there northwards the range continues to rise, passing Lincoln Peak, Mt. Washington, Pyramid Peak, Baker Peak and it finally reaching its apex at Wheeler Peak. North of Wheeler Peak the range begins to drop, reaching 7,154 feet at Sacramento Pass, Sacramento Pass is where the more remote northern section of the range begins. In just 12 miles the range rises past Silver Creek Canyon, to the north of this peak is an unusual formation, a flat plateau of sub-alpine tundra called The Table, covering about 2 square miles at an elevation of 11,000 feet. A grove of ancient Great Basin Bristlecone Pines grows on this plateau near the peak, north of The Table is another unusual geologic feature. Deadman Creek and Smith Creek, draining eastward into Snake Valley, the mouth of this canyon lies below 3, 000-foot cliffs,6,000 feet below and 6 miles away from the summit of Mt. Moriah
4.
Great Basin National Park
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Great Basin National Park is a United States National Park located in White Pine County in east-central Nevada, near the Utah border. The park was established in 1986 and it is most commonly accessed by way of Nevada State Route 488, which is connected to U. S. Routes 6 and 50 by Nevada State Route 487 via the town of Baker. The park derives its name from the Great Basin, the dry, topographically, this area is known as the Basin and Range Province. The park is located approximately 290 miles north of Las Vegas, the park is notable for its groves of ancient bristlecone pines, the oldest known non-clonal organisms, and for the Lehman Caves at the base of 13, 063-foot Wheeler Peak. The peak is home to Wheeler Peak Glacier, which despite claims is much further north than Mount Everest. President Warren G. Harding created Lehman Caves National Monument by presidential proclamation on January 24,1922 and it was designated a national park on October 27,1986. There are a number of developed campsites within the park, as well as excellent back country camping opportunities, adjacent to Great Basin National Park lies the Highland Ridge Wilderness. These two protected areas provide contiguous wildlife habitat and protection to 227.8 square miles of eastern Nevadas basin lands, there are 11 species of conifer trees and over 800 species of plants in Great Basin National Park and the neighboring valleys. The area around the Visitor Center is dominated by such as sagebrush, saltbush, Single-leaf Pinyon. Higher elevations are home to mountain meadows, White Fir, Quaking Aspen, Englemann Spruce, at treeline is an alpine area of low, delicate plants and rocky outcroppings. The oldest non-clonal organism ever discovered, a Great Basin Bristlecone Pine tree at least 5,000 years old and it was cut down in 1964 by a graduate student and U. S. Forest Service personnel for research purposes. It was given the nickname Prometheus, after the figure who stole fire from the gods. There are 61 species of mammals,18 species of reptiles,238 species of birds,2 species of amphibians, and 8 species of fish in Great Basin National Park, mammals An abundance of wildlife has taken advantage of the habitat zones in Great Basin National Park. Jackrabbits, pygmy rabbits, mountain cottontails, ground squirrels, chipmunks, pronghorns, coyotes, kit foxes, and badgers are less common inhabitants. In the more rugged areas on the slopes of mountains and in the areas nearby, cougars, bobcats, marmots, rock squirrels. Other animals that can be found here include elk, mule deer, spotted skunks, shrew, ringtail cats, fish The Bonneville cutthroat trout is the only fish native to Great Basin National Park. It arrived in the mountain waters naturally and was isolated by changing climatic conditions
5.
Civilization
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Historically, a civilization was a so-called advanced culture in contrast to more supposedly primitive cultures. As an uncountable noun, civilization also refers to the process of a society developing into a centralized, urbanized, stratified structure, Civilization concentrates power, extending human control over the rest of nature, including over other human beings. The earlier neolithic technology and lifestyle was established first in the Middle East, and later in the Yangtze and Yellow River basins in China, similar pre-civilized neolithic revolutions also began independently from 7,000 BCE in such places as northwestern South America and Mesoamerica. These were among the six civilizations worldwide that arose independently, Mesopotamia is the site of the earliest developments of the Neolithic Revolution from around 10,000 BCE, with civilizations developing from 6,500 years ago. Towards the end of the Neolithic period, various elitist Chalcolithic civilizations began to rise in various cradles from around 3300 BCE. Chalcolithic civilizations, as defined above, also developed in Pre-Columbian Americas and, despite an early start in Egypt, Axum and Kush, the English word civilization comes from the 16th-century French civilisé, from Latin civilis, related to civis and civitas. The fundamental treatise is Norbert Eliass The Civilizing Process, which traces social mores from medieval courtly society to the Early Modern period, in The Philosophy of Civilization, Albert Schweitzer outlines two opinions, one purely material and the other material and ethical. Adjectives like civility developed in the mid-16th century, the abstract noun civilization, meaning civilized condition, came in the 1760s, again from French. The word was therefore opposed to barbarism or rudeness, in the pursuit of progress characteristic of the Age of Enlightenment. In the late 1700s and early 1800s, during the French revolution, civilization was used in the singular, never in the plural and this is still the case in French. The use of civilizations as a noun was in occasional use in the 19th century. Only in this sense does it become possible to speak of a medieval civilization. Already in the 18th century, civilization was not always seen as an improvement, one historically important distinction between culture and civilization is from the writings of Rousseau, particularly his work about education, Emile. From this, a new approach was developed, especially in Germany, first by Johann Gottfried Herder and this sees cultures as natural organisms, not defined by conscious, rational, deliberative acts, but a kind of pre-rational folk spirit. Civilization, in contrast, though more rational and more successful in material progress, is unnatural and leads to vices of social life such as guile, hypocrisy, envy and avarice. In World War II, Leo Strauss, having fled Germany, argued in New York that this opinion of civilization was behind Nazism, Social scientists such as V. Gordon Childe have named a number of traits that distinguish a civilization from other kinds of society. Andrew Nikiforuk argues that civilizations relied on shackled human muscle and it took the energy of slaves to plant crops, clothe emperors, and build cities and considers slavery to be a common feature of pre-modern civilizations. All civilizations have depended on agriculture for subsistence, grain farms can result in accumulated storage and a surplus of food, particularly when people use intensive agricultural techniques such as artificial fertilization, irrigation and crop rotation
6.
Fremont culture
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In the Navajo culture the pictographs are credited to people who lived before the flood. The Fremont River itself is named for John Charles Frémont, an American explorer and it inhabited sites in what is now Utah and parts of Nevada, Idaho and Colorado from AD1 to 1300. It was adjacent to, roughly contemporaneous with, but distinctly different from the Ancestral Pueblo peoples located to their south, Fremont Indian State Park in the Clear Creek Canyon area in south-central Utah contains the biggest Fremont culture site in Utah. Thousand-year-old pit houses, petroglyphs, and other Fremont artifacts were discovered at Range Creek, nearby Nine Mile Canyon has long been known for its large collection of Fremont rock art. Other sites are found in The San Rafael Swell, Capitol Reef National Park, Dinosaur National Monument, Zion National Park, first, Fremont culture people foraged wild food sources and grew corn. The culture participated in a continuum of fairly reliable subsistence strategies that no doubt varied from place to place, other unifying characteristics include the manufacture of relatively expedient gray ware pottery and a signature style of basketry and rock art. Most of the Fremont lived in single and extended family units comprising villages ranging from two to a dozen pithouse structures, with only a few having been occupied at any one time. The Fremont are sometimes thought to have begun as a group of the Ancestral Pueblo people. According to archaelogist Dean Snow, Fremont people generally wore moccasins like their Great Basin ancestors rather than sandals like the Ancestral Puebloans and they were part-time farmers who lived in scattered semi-sedentary farmsteads and small villages, never entirely giving up traditional hunting and gathering for more risky full-time farming. Snow notes that Fremont culture declined due to changing climate conditions c.950 CE, the culture moved to the then-marshy areas of northwestern Utah, which sustained them for about 400 years. Traces of Fremont, Society and Rock Art in Ancient Utah, text by Steven R. Simms, photographs by Francois Gohier. ISBN 978-1-60781-011-7 Snow, Dean R. Archaeology of Native North America, video on Fremont culture- Scientific American Frontiers
7.
Bureau of Land Management
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President Harry S. Truman created the BLM in 1946 by combining two existing agencies, the General Land Office and the Grazing Service. Most BLM public lands are located in these 12 western states, Alaska, Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington and Wyoming. The mission of the BLM is to sustain the health, diversity, originally BLM holdings were described as land nobody wanted because homesteaders had passed them by. All the same, ranchers hold nearly 18,000 permits, the agency manages 221 wilderness areas,23 national monuments and some 636 other protected areas as part of the National Landscape Conservation System totaling about 30 million acres. There are more than 63,000 oil and gas wells on BLM public lands, total energy leases generated approximately $5.4 billion in 2013, an amount divided among the Treasury, the states, and Native American groups. The BLMs roots go back to the Land Ordinance of 1785 and these laws provided for the survey and settlement of the lands that the original 13 colonies ceded to the federal government after the American Revolution. As additional lands were acquired by the United States from Spain, France and other countries, the United States Congress directed that they be explored, surveyed, during the Revolutionary War, military bounty land was promised to soldiers who fought for the colonies. After the war, the Treaty of Paris of 1783, signed by the United States, England, France, in the 1780s, other states relinquished their own claims to land in modern-day Ohio. By this time, the United States needed revenue to function, Land was sold so that the government would have money to survive. In order to sell the land, surveys needed to be conducted, the Land Ordinance of 1785 instructed a geographer to oversee this work as undertaken by a group of surveyors. The first years of surveying were completed by trial and error, once the territory of Ohio had been surveyed, in 1812, Congress established the General Land Office as part of the Department of the Treasury to oversee the disposition of these federal lands. By the early 1800s, promised bounty land claims were finally fulfilled, over the years, other bounty land and homestead laws were enacted to dispose of federal land. Several different types of patents existed and these include cash entry, credit, homestead, Indian, military warrants, mineral certificates, private land claims, railroads, state selections, swamps, town sites, and town lots. A system of land offices spread throughout the territories, patenting land that was surveyed via the corresponding Office of the Surveyor General of a particular territory. This pattern gradually spread across the entire United States, the laws that spurred this system with the exception of the General Mining Law of 1872 and the Desert Land Act of 1877 have since been repealed or superseded. The Mineral Leasing Act of 1920 allowed leasing, exploration, and production of selected commodities, such as coal, oil, gas, the Taylor Grazing Act of 1934 established the United States Grazing Service to manage the public rangelands by establishment of advisory boards that set grazing fees. The Oregon and California Revested Lands Sustained Yield Management Act of 1937, commonly referred as the O&C Act, in 1946, the Grazing Service was merged with the General Land Office to form the Bureau of Land Management within the Department of the Interior. It took several years for new agency to integrate and reorganize
8.
U.S. Route 50 in Nevada
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U. S. Route 50 is a transcontinental highway in the United States, stretching from West Sacramento, California, in the west to Ocean City, Maryland, on the east coast. The Nevada portion crosses the center of state and was named The Loneliest Road in America by Life magazine in July 1986, the name was intended as a pejorative, but Nevada officials seized on it as a marketing slogan. The name originates from large desolate areas traversed by the route, the highway crosses several large desert valleys separated by numerous mountain ranges towering over the valley floors, in what is known as the Basin and Range province of the Great Basin. The route was constructed over a historic corridor, first used for the Pony Express and Central Overland Route, before the formation of the U. S. Highway System, most of US50 in Nevada was designated State Route 2. The routing east of Ely has changed significantly from the original plans, the route change resulted from a rivalry between Nevada and Utah over which transcontinental route was better to serve California bound traffic, the Lincoln Highway or the Victory Highway. US50 crosses the central portion of Nevada, entering the west side of the state near Lake Tahoe, the route crosses mostly desolate terrain in the journey across the state, US50 passes through several large desert valleys and basins. The highway crosses 17 named mountain passes that break up the Nevada desert, to crest some of the passes along US50 requires navigating steep 8% grades and hairpin turns through pine forests to reach elevations of over 7,000 feet. In the stretch of highway between Fallon and Delta, Utah, a span of 409 miles, there are three towns, Austin, Eureka and Ely. This span is roughly the distance as Boston, Massachusetts to Baltimore, Maryland or Paris, France to Zürich. Traffic along US50 varies greatly, the average annual daily traffic in 2007 ranged from 52,000 vehicles per day in Carson City, to 530 vehicles per day near the Duckwater turnoff. US50 enters Nevada from California as a four lane thoroughfare on the shores of alpine Lake Tahoe in Stateline. The highway follows the shore, squeezing between the lake and the crest of the Carson Range. In one narrow spot, the cuts through the mountains via the Cave Rock Tunnel. Eventually, the route crests the Carson Range at Spooner Summit and then descends into Nevadas capital, after Carson City, US50 follows the Carson River towards the Lahontan Valley. This portion is mostly four lane, serving the commuter towns of Dayton and Silver Springs as well as passing by Fort Churchill State Historic Park. In addition to the trails of the Pony Express and Lincoln Highway, the Carson River forms the southern edge of the Forty Mile Desert. At Silver Springs, U. S. Route 50 Alternate splits from the main route, both branches are sometimes called the loneliest road, although the official designation begins with the first passport stamp available at Fernley, along the alternate branch. The two branches rejoin west of Fallon, Fallon, home to the Naval Air Station Fallon or TOPGUN, is an agricultural community along the last usable water of the Carson River
9.
Water
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Water is a transparent and nearly colorless chemical substance that is the main constituent of Earths streams, lakes, and oceans, and the fluids of most living organisms. Its chemical formula is H2O, meaning that its molecule contains one oxygen, Water strictly refers to the liquid state of that substance, that prevails at standard ambient temperature and pressure, but it often refers also to its solid state or its gaseous state. It also occurs in nature as snow, glaciers, ice packs and icebergs, clouds, fog, dew, aquifers, Water covers 71% of the Earths surface. It is vital for all forms of life. Only 2. 5% of this water is freshwater, and 98. 8% of that water is in ice and groundwater. Less than 0. 3% of all freshwater is in rivers, lakes, and the atmosphere, a greater quantity of water is found in the earths interior. Water on Earth moves continually through the cycle of evaporation and transpiration, condensation, precipitation. Evaporation and transpiration contribute to the precipitation over land, large amounts of water are also chemically combined or adsorbed in hydrated minerals. Safe drinking water is essential to humans and other even though it provides no calories or organic nutrients. There is a correlation between access to safe water and gross domestic product per capita. However, some observers have estimated that by 2025 more than half of the population will be facing water-based vulnerability. A report, issued in November 2009, suggests that by 2030, in developing regions of the world. Water plays an important role in the world economy, approximately 70% of the freshwater used by humans goes to agriculture. Fishing in salt and fresh water bodies is a source of food for many parts of the world. Much of long-distance trade of commodities and manufactured products is transported by boats through seas, rivers, lakes, large quantities of water, ice, and steam are used for cooling and heating, in industry and homes. Water is an excellent solvent for a variety of chemical substances, as such it is widely used in industrial processes. Water is also central to many sports and other forms of entertainment, such as swimming, pleasure boating, boat racing, surfing, sport fishing, Water is a liquid at the temperatures and pressures that are most adequate for life. Specifically, at atmospheric pressure of 1 bar, water is a liquid between the temperatures of 273.15 K and 373.15 K
10.
Las Vegas Valley
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The Las Vegas Valley is a major metropolitan area located in the southern part of the U. S. state of Nevada. The largest urban agglomeration in the state, it is the heart of the Las Vegas–Paradise-Henderson, the Valley is largely defined by the Las Vegas Valley landform, a 600 sq mi basin area surrounded by mountains to the north, south, east and west of the metropolitan area. The Valley is home to the three largest incorporated cities in Nevada, Las Vegas, Henderson and North Las Vegas, six unincorporated towns governed by the Clark County government are part of the Las Vegas Township and constitute the largest community in the state of Nevada. Since the 1990s the Las Vegas Valley has seen exponential growth, in 2014, a record breaking 41 million visited the Las Vegas area, producing a gross metropolitan product of more than $100 billion. The first reported non-Native American visitor to the Las Vegas Valley was the Mexican scout Rafael Rivera in 1829. Las Vegas was named by Mexicans in the Antonio Armijo party, including Rivera, in the 19th century, areas of the valley contained artesian wells that supported extensive green areas, or meadows, hence the name Las Vegas. The area was settled by Mormon farmers in 1854 and later became the site of a United States Army fort in 1864. Since the 1930s, Las Vegas has generally been identified as a center as well as a resort destination. Nellis Air Force Base is located in the northeast corner of the valley, the ranges that the Nellis pilots use and various other land areas used by various federal agencies, limit growth of the valley in terms of geographic area. Businessman Howard Hughes arrived in the late 1960s and purchased many casino hotels, as well as television, legitimate corporations began to purchase casino hotels as well, and the mob was run out by the federal government over the next several years. The constant stream of tourist dollars from the hotels and casinos was augmented by a new source of money from the establishment of what is now Nellis Air Force Base. The influx of personnel and casino job-hunters helped start a land building boom which is now leveling off. The Las Vegas area remains one of the top entertainment destinations. The valley is contained in the Las Vegas Valley landform and this includes the cities of Las Vegas, North Las Vegas, and Henderson, and the unincorporated towns of Paradise, Spring Valley, Sunrise Manor, Enterprise, Winchester, and Whitney. The valley is located within the larger metropolitan area, as the metropolitan area covers all of Clark County -including parts that do not fall within the valley. The government of Clark County has an Urban Planning Area of Las Vegas and this definition is a roughly rectangular area, about 20 mi from east to west and 30 miles from north to south. Notable exclusions from the Urban Planning Area include Red Rock, Blue Diamond, the Las Vegas Metropolitan Police Department is the largest police department in the valley and the state and exercises jurisdiction in the entire county. The department does not exercise jurisdiction in areas with separate police forces such as North Las Vegas, Henderson, Boulder City, Nellis Air Force Base
11.
Great Basin Desert
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The Great Basin Desert is part of the Great Basin between the Sierra Nevada and the Wasatch Range. It is a desert with hot, dry summers and snowy winters. The desert spans a large part of the state of Nevada, and extends into western Utah, eastern California, the desert is one of the four biologically defined deserts in North America, in addition to the Mojave, Sonoran, and Chihuahuan Deserts. Basin and range topography characterizes the desert, wide valleys bordered by mountain ranges generally oriented north-south. There are more than 33 peaks within the desert with summits higher than 9,800 feet, the biological communities of the Great Basin Desert vary according to altitude, from low salty dry lakes, up through rolling sagebrush valleys, to pinyon-juniper forests. According to Grayson, more than 600 species of live in the floristic Great Basin. Sixty-three of these species have been identified as species of concern due to contracting natural habitats. The ecology of the desert varies across geography, also, different locations in the desert have different amounts of precipitation, depending on the strength of these rain shadows. The environment is influenced by Pleistocene lakes that dried after the last ice age, Lake Lahontan, each of these lakes left different amounts of salinity and alkalinity. The Great Basin Desert is defined by its animals and plants, scientists have different definitions of the Great Basin Desert, which are often defined by negatives. J. Robert Macey defines the Great Basin scrub desert as lacking creosote bush, the Great Basin Desert includes several arid basins lacking Larrea tridentata such as the Chalfant, Hammil, Benton, and Queen valleys, as well as all but the southeast portion of the Owens Valley. Conversely, the Panamint, Saline, and Eureka valleys have creosote bush, the study and definition of ecoregions can also indicate the boundaries of the Great Basin Desert. In 1987, J. M. Omernik defined a desert ecoregion between the Sierra Nevada and Wasatch Range, naming it the Northern Basin and Range ecoregion. In 1999, the U. S. EPA renamed the Northern Basin and Range to Central Basin and Range and he states that the Great Basin Desert is encompassed within that area. This article describes the ecology of the region, including the high-elevation areas. See Great Basin montane forests for more details on the high-elevation ecoregion. This is the climate of the high desert, the Great Basin desert climate begins with the Sierra Nevada in eastern California. Rising 14,000 feet above sea level, this mountain range casts a rain shadow over the desert
12.
Groundwater
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Groundwater is the water present beneath Earths surface in soil pore spaces and in the fractures of rock formations. A unit of rock or a deposit is called an aquifer when it can yield a usable quantity of water. The depth at which pore spaces or fractures and voids in rock become completely saturated with water is called the water table. Groundwater is recharged from, and eventually flows to, the naturally, natural discharge often occurs at springs and seeps. Groundwater is also withdrawn for agricultural, municipal, and industrial use by constructing and operating extraction wells. The study of the distribution and movement of groundwater is hydrogeology, Groundwater is hypothesized to provide lubrication that can possibly influence the movement of faults. It is likely that much of Earths subsurface contains some water, Groundwater may not be confined only to Earth. The formation of some of the landforms observed on Mars may have influenced by groundwater. There is also evidence that water may also exist in the subsurface of Jupiters moon Europa. Groundwater is often cheaper, more convenient and less vulnerable to pollution than surface water, therefore, it is commonly used for public water supplies. For example, groundwater provides the largest source of water storage in the United States. Underground reservoirs contain far more water than the capacity of all surface reservoirs and lakes in the US, many municipal water supplies are derived solely from groundwater. Polluted groundwater is less visible, but more difficult to clean up, than pollution in rivers, Groundwater pollution most often results from improper disposal of wastes on land. An aquifer is a layer of substrate that contains and transmits groundwater. When water can flow directly between the surface and the zone of an aquifer, the aquifer is unconfined. The deeper parts of unconfined aquifers are more saturated since gravity causes water to flow downward. The upper level of this layer of an unconfined aquifer is called the water table or phreatic surface. Below the water table, where in general all pore spaces are saturated with water, is the phreatic zone, substrate with low porosity that permits limited transmission of groundwater is known as an aquitard
