Ecology of California - AbsoluteAstronomy.com

The ecology of California is diverse: it is considered to span six biogeographic provinces or ecoregions

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...

: "Coastal Chaparral Forest and Shrub", "Dry Steppe", "Coastal Steppe, Mixed Forest, and Redwood Forest", "Sierran Steppe/Mixed Forest/Coniferous Forest", "Coastal Range Open Woodland/Shrub/ Coniferous Forest/Meadow", and "American Semi-Desert and Desert".

Botanists generally consider the California chaparral and woodlands, Sierra Nevada forests, Central Valley grasslands, Northern California coastal forests, and Klamath-Siskiyou as a single California Floristic Province

California Floristic Province

The California Floristic Province is a floristic province with a Mediterranean climate located on the Pacific Coast of North America with a distinctive flora that bears similarities to floras found in other regions experiencing a winter rainfall, summer drought climate like the Mediterranean...

, which does not include the deserts of eastern California, which belong to other floristic provinces. Many Bioregionalists

Bioregionalism

Bioregionalism is a political, cultural, and environmental system or set of views based on naturally defined areas called bioregions, similar to ecoregions. Bioregions are defined through physical and environmental features, including watershed boundaries and soil and terrain characteristics...

, including poet Gary Snyder

Gary Snyder

Gary Snyder is an American poet , as well as an essayist, lecturer, and environmental activist . Snyder is a winner of a Pulitzer Prize for Poetry...

, identify the central and northern Coast Ranges, Klamath-Siskiyou, the Central Valley, and Sierra Nevada as Alta California or the Shasta Bioregion.

Semi-desert and desert

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...

's high mountains block most moisture from reaching the eastern parts of the state, which are home to California's desert and xeric shrub

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:...

ecoregions. The low desert of southeastern California is part of the Sonoran desert

Sonoran Desert

The Sonoran Desert is a North American desert which straddles part of the United States-Mexico border and covers large parts of the U.S. states of Arizona and California and the northwest Mexican states of Sonora, Baja California, and Baja California Sur. It is one of the largest and hottest...

ecoregion, which extends into Arizona

Arizona

Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...

and parts of northern Mexico

Mexico

The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

. Southern California's high deserts constitute the Mojave desert

Mojave Desert

The Mojave Desert occupies a significant portion of southeastern California and smaller parts of central California, southern Nevada, southwestern Utah and northwestern Arizona, in the United States...

ecoregion, which has affinities to the Great Basin shrub steppe

Great Basin shrub steppe

The Great Basin shrub steppe ecoregion, within the Deserts and xeric shrublands Biome, includes various xeric shrub-steppe sub-ecoregions in the Great Basin region of the Western United States.It is within the North American Desert region, and includes much of Nevada, eastern and northeastern...

, which covers California's 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...

and Modoc Plateau

Modoc Plateau

The Modoc Plateau lies in the northeast corner of California as well as parts of Oregon and Nevada. It is a mile-high expanse of lava flows with cinder cones, juniper flats, pine forests, and seasonal lakes. The plateau is thought to have been formed approximately 25 million years ago...

, as well as most of neighboring 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...

Coastal chaparral

The southern and central Coast Ranges, including the San Francisco Bay Area

San Francisco Bay Area

The San Francisco Bay Area, commonly known as the Bay Area, is a populated region that surrounds the San Francisco and San Pablo estuaries in Northern California. The region encompasses metropolitan areas of San Francisco, Oakland, and San Jose, along with smaller urban and rural areas...

and Los Angeles

Los Angeles, California

Los Angeles , with a population at the 2010 United States Census of 3,792,621, is the most populous city in California, USA and the second most populous in the United States, after New York City. It has an area of , and is located in Southern California...

region, comprise California's Mediterranean Forests, Woodlands, and Scrub

Mediterranean forests, woodlands, and scrub

Mediterranean forests, woodlands, and scrub biome, defined by the World Wildlife Fund, characterized by dry summers and rainy winters. Summers are typically hot in low-lying inland locations but can be cool near some seas, as near San Francisco, which have a sea of cool waters...

ecoregions. These contain numerous plant communities, including oak savanna, oak woodland, conifer woodlands, chaparral, coastal sage scrub, and coastal grassland; these plant communities often occur as a mosaic, with patches of distinct plant communities situated in response to site conditions, including variations in sun exposure (north or south slopes), wind exposure, and soils, and variations in rainfall between wetter seaward slopes and the drier 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...

on the landward slopes.

In the south, the California coastal sage and chaparral extends across the Mexican border into northwestern Baja California

Baja California

Baja California officially Estado Libre y Soberano de Baja California is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is both the northernmost and westernmost state of Mexico. Before becoming a state in 1953, the area was known as the North...

and Los Angeles. The California montane chaparral and woodlands

California montane chaparral and woodlands

The California montane chaparral and woodlands ecoregion covers , including the mountains of the Transverse, Peninsular, and Santa Lucia Ranges of California. It is part of the Mediterranean forests, woodlands, and scrub biome, with cool, wet winters and hot, dry summers...

include the Transverse Ranges

Transverse Ranges

The Transverse Ranges are a group of mountain ranges of southern California, in the Pacific Coast Ranges physiographic region that runs along the Pacific coast from Alaska to Mexico in North America. The Transverse Ranges begin at the southern end of the California Coast Ranges and lie between...

north of Los Angeles as well as the Santa Lucia Range on the Central Coast

Central Coast of California

The Central Coast is an area of California, United States, roughly spanning the area between the Monterey Bay and Point Conception. It extends through Santa Cruz County, San Benito County, Monterey County, San Luis Obispo County, and Santa Barbara County...

. The California interior chaparral and woodlands

California interior chaparral and woodlands

The California interior chaparral and woodlands ecoregion covers in an elliptical ring around the California Central Valley. It occurs on hills and mountains ranging from to . It is part of the Mediterranean forests, woodlands, and scrub biome, with cool, wet winters and hot, dry summers...

form a ring around the Central Valley, covering the hills around the Bay Area as well as the foothills of the Sierra Nevada.

Dry steppe

California's Central Valley was once a large temperate grassland

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....

, the California Central Valley grasslands ecoregion, which was formerly home to great herds of grazing pronghorn

Pronghorn

The pronghorn is a species of artiodactyl mammal endemic to interior western and central North America. Though not an antelope, it is often known colloquially in North America as the prong buck, pronghorn antelope, or simply antelope, as it closely resembles the true antelopes of the Old World and...

and elk

Elk

The Elk is the large deer, also called Cervus canadensis or wapiti, of North America and eastern Asia.Elk may also refer to:Other antlered mammals:...

; some writers have referred to it as "America's Serengeti

Serengeti

The Serengeti ecosystem is a geographical region in Africa. It is located in north Tanzania and extends to south-western Kenya between latitudes 1 and 3 S and longitudes 34 and 36 E. It spans some ....

". The Central Valley has been mostly converted to farms and rangeland; its once great seasonal wetlands have been drained and its perennial bunch grasses replaced by exotic annual grasses or farm fields, but patches of the native bunchgrasses still exist, as do some of the small seasonal wetlands known as vernal pool

Vernal pool

Vernal pools, also called vernal ponds or ephemeral pools, are temporary pools of water. They are usually devoid of fish, and thus allow the safe development of natal amphibian and insect species...

Temperate coniferous forests

The cooler and wetter mountains of northern California are covered by 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...

. Along the eastern edge of California, the mountainous Sierra Nevada forests are home to the world's most massive tree, the Giant Sequoia (Sequoiadendron giganteum) and the contiguous United States' highest point, Mount Whitney

Mount Whitney

Mount Whitney is the highest summit in the contiguous United States with an elevation of . It is on the boundary between California's Inyo and Tulare counties, west-northwest of the lowest point in North America at Badwater in Death Valley National Park...

. Wet-season rain and dry-season fog support the Northern California coastal forests

Northern California coastal forests

The Northern California coastal forests are a temperate coniferous forests ecoregion of coastal Northern California, USA.-Setting:The ecoregion lies close to the Pacific Ocean, and is kept moist by Pacific Ocean storms during the winter months, and by coastal fogs in the summer months...

, which grow the world's tallest tree, the Coast redwood (Sequoia sempervirens). Inland, the Klamath-Siskiyou forests support some of the world's most diverse coniferous forests. In sparsely-populated northeastern are the Eastern Cascades forests.

Semi-desert and desert

Coastal chaparral

Dry steppe

Temperate coniferous forests

See also