Great Basin shrub steppe
Encyclopedia
The Great Basin shrub steppe ecoregion
Ecoregion
An ecoregion , sometimes called a bioregion, is an ecologically and geographically defined area that is smaller than an ecozone and larger than an ecosystem. Ecoregions cover relatively large areas of land or water, and contain characteristic, geographically distinct assemblages of natural...

, within the Deserts and xeric shrublands
Deserts and xeric shrublands
Deserts and xeric shrublands is a biome characterized by, relating to, or requiring only a small amount of moisture.-Definition and occurrence:...

 Biome
Biome
Biomes are climatically and geographically defined as similar climatic conditions on the Earth, such as communities of plants, animals, and soil organisms, and are often referred to as ecosystems. Some parts of the earth have more or less the same kind of abiotic and biotic factors spread over a...

, includes various xeric shrub-steppe
Shrub-steppe
Shrub-steppe is a type of low rainfall natural grassland. Shrub-steppes are distinguishable from deserts, which are too dry to support a noticeable cover of perennial grasses or other shrubs, while the shrub-steppe has sufficient moisture levels to support a cover of perennial grasses and/or...

 sub-ecoregions in the Great Basin
Great Basin
The Great Basin is the largest area of contiguous endorheic watersheds in North America and is noted for its arid conditions and Basin and Range topography that varies from the North American low point at Badwater Basin to the highest point of the contiguous United States, less than away at the...

 region of the Western United States
Western United States
.The Western United States, commonly referred to as the American West or simply "the West," traditionally refers to the region comprising the westernmost states of the United States. Because the U.S. expanded westward after its founding, the meaning of the West has evolved over time...

.It is within the North American Desert
North American Desert
The North American Deserts includes all the deserts located on the continent. It is also the term for a large U.S. Level 1 ecoregion of the North American Cordillera, in the Deserts and xeric shrublands biome...

 region, and includes much of Nevada
Nevada
Nevada is a state in the western, mountain west, and southwestern regions of the United States. With an area of and a population of about 2.7 million, it is the 7th-largest and 35th-most populous state. Over two-thirds of Nevada's people live in the Las Vegas metropolitan area, which contains its...

, eastern and northeastern California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

 east of the Sierra Nevada and Cascade Range
Cascade Range
The Cascade Range is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as the North Cascades, and the notable volcanoes known as the High Cascades...

 rain shadow
Rain shadow
A rain shadow is a dry area on the lee side of a mountainous area. The mountains block the passage of rain-producing weather systems, casting a "shadow" of dryness behind them. As shown by the diagram to the right, the warm moist air is "pulled" by the prevailing winds over a mountain...

s, and parts of Idaho
Idaho
Idaho is a state in the Rocky Mountain area of the United States. The state's largest city and capital is Boise. Residents are called "Idahoans". Idaho was admitted to the Union on July 3, 1890, as the 43rd state....

 and Utah
Utah
Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...

. The Great Basin Desert
Great Basin Desert
The Great Basin Desert is an area of nearctic high deserts across parts of Nevada, California, and Utah that extends into the Colorado River watershed , but which is mostly a portion of the central Nevada desert basins of the Great Basin.It along with the Escalante Desert, Mohave Desert, the...

 and semi-arid non-desert xeric shrubland species include Sagebrush (Artemisia tridentata)
Artemisia tridentata
Artemisia tridentata is a shrub or small tree from the family Asteraceae. Some botanists treat it in the segregate genus Seriphidium, as S. tridentatum W. A. Weber, but this is not widely followed...

 and Spiny Hop Sage (Grayia spinosa)
Grayia (plant)
Grayia is a monotypic genus of plants containing the sole species Grayia spinosa, which is known by the common names hop sage and spiny hop sage.-Distribution:...

.

Adjacent biomes

The sagebrush steppe
Sagebrush steppe
The sagebrush steppe is a type of shrub-steppe, which is a dry-xeric environment and plant community found in the Western United States and western Canada...

 ecoregions are often in elevated desert areas (annual precipitation <10 inches per year) and have ecotones between other Nearctic
Nearctic
The Nearctic is one of the eight terrestrial ecozones dividing the Earth's land surface.The Nearctic ecozone covers most of North America, including Greenland and the highlands of Mexico...

 biomes in this part of the Great Basin. These include: Temperate coniferous forests
Temperate coniferous forests
Temperate coniferous forest is a terrestrial biome found in temperate regions of the world with warm summers and cool winters and adequate rainfall to sustain a forest. In most temperate coniferous forests, evergreen conifers predominate, while some are a mix of conifers and broadleaf evergreen...

, Temperate grasslands, savannas, and shrublands
Temperate grasslands, savannas, and shrublands
Temperate grasslands, savannas, and shrublands is a terrestrial biome whose predominant vegetation consists of grasses and/or shrubs. The climate is temperate and semi-arid to semi-humid....

, Riparian, and highest elevation (subalpine) Taiga and Boreal forests
Taiga
Taiga , also known as the boreal forest, is a biome characterized by coniferous forests.Taiga is the world's largest terrestrial biome. In North America it covers most of inland Canada and Alaska as well as parts of the extreme northern continental United States and is known as the Northwoods...

. "Great Basin Desert
Great Basin Desert
The Great Basin Desert is an area of nearctic high deserts across parts of Nevada, California, and Utah that extends into the Colorado River watershed , but which is mostly a portion of the central Nevada desert basins of the Great Basin.It along with the Escalante Desert, Mohave Desert, the...

" is an outdated term for the shrub steppe with a herpetofaunal set of valleys in the Great Basin
Great Basin
The Great Basin is the largest area of contiguous endorheic watersheds in North America and is noted for its arid conditions and Basin and Range topography that varies from the North American low point at Badwater Basin to the highest point of the contiguous United States, less than away at the...

 that characteristically "lacks Creosote Bush" and which was defined for the purposes of a 1964 report by J. Robert Macey who distinguished "Great Basin Scrub desert" versus "Creosote Bush desert". Instead of a desert with <10 inches precipitation per annum, the analyzed ecoregion "of the valleys that surround the Inyo and White mountains" includes several arid basins without Larrea tridentata (chaparral) such as the "Chalfant, Hammil, Benton and Queen valleys", as well as all but a southeast portion of the Owens Valley
Owens Valley
Owens Valley is the arid valley of the Owens River in eastern California in the United States, to the east of the Sierra Nevada and west of the White Mountains and Inyo Mountains on the west edge of the Great Basin section...

. Conversely, the "Panamint
Panamint Valley
The Panamint Valley is a long basin located east of the Argus Range and Slate Range, and west of the Panamint Range in the northeastern reach of the Mojave Desert, in eastern California, United States.-Geography:...

, Saline, and Eureka
Eureka Valley
The name Eureka Valley refers to two distinct places in the U.S. state of California:*Eureka Valley, San Francisco, California, a neighborhood*Eureka Valley , a valley...

 valleys" contain Creosote Bush, versus the Deep Springs Valley
Deep Springs Valley
Deep Springs Valley is a high desert valley in the Inyo-White Mountains of Inyo County, California. It is east of the Owens Valley and the Sierra Nevada mountain range, and south of Fish Lake Valley, Nevada, near the California-Nevada state border....

 which contains Great Basin Scrub desert.

Examples

The Black Rock Desert
Black Rock Desert
The Black Rock Desert is an arid region in the northern Nevada section of the Great Basin with a lakebed that is a dry remnant of Pleistocene Lake Lahontan...

 is in the Central Basin and Range ecoregion
Central Basin and Range ecoregion
The Central Basin and Range ecoregion is a Level III ecoregion designated by the United States Environmental Protection Agency with 26 different Level IV ecoregions...

 at the edge of the Northern Basin and Range ecoregion
Northern Basin and Range (ecoregion)
The Northern Basin and Range ecoregion is a Level III ecoregion designated by the United States Environmental Protection Agency in the U.S. states of Oregon, Idaho, Nevada, Utah, and California. It contains dissected lava plains, rolling hills, alluvial fans, valleys, and scattered mountain ranges...

 and has two Level IV ecoregions: Lahontan Salt Shrub Basin and a non-shrub-steppe ecoregion, Lahontan Playa.

In the Dixie Valley
Dixie Valley
The Dixie Valley is an endorheic basin which had plentiful ground water around which ranches were built. Prior to the US Navy TOPGUN school moving from California to Nevada, the valley was purchased in 1995 for $100 million and is used as an electronic warfare range for nearby Fallon Naval Air...

 watershed
Drainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...

, the sub-ecoregions of Central Basin and Range ecoregion
Central Basin and Range ecoregion
The Central Basin and Range ecoregion is a Level III ecoregion designated by the United States Environmental Protection Agency with 26 different Level IV ecoregions...

 are a more complex example with shrubs on the slopes. The Dixie Valley
Dixie Valley
The Dixie Valley is an endorheic basin which had plentiful ground water around which ranches were built. Prior to the US Navy TOPGUN school moving from California to Nevada, the valley was purchased in 1995 for $100 million and is used as an electronic warfare range for nearby Fallon Naval Air...

 watershed has a floor with elevation >3000 ft (914.4 m) and, like the Black Rock Desert, has both the Lahontan Salt Shrub Basin and Lahontan Playa ecoregions. But additionally at higher elevations are the Dixie Valley's Lahontan Sagebrush Slope (west) and Central Nevada High Valley (east) ecoregions that transition to the mountainous Lahontan Upland and Central Nevada Mid-Slope Woodland & Brushland ecoregions (the latter's summits are Central Nevada Bald Mountain ecoregions).

See also

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