Sonoran Desert

The Sonoran Desert (sometimes called the Gila Desert after the Gila River or the Low Desert in opposition to the higher Mojave 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 Mexican states of Sonora and Baja California. It is one of the largest and hottest deserts in North America, with an area of 311,000 km² (120,000 mi² ). The desert contains a variety of unique plants and animals, such as the saguaro cactus. On January 17, 2001, 2,008 km² (496,337 acres) of the Sonoran Desert was set aside as the Sonoran Desert National Monument for the purpose of enhancing resource protection.

Location

The Sonoran Desert wraps around the northern end of the Gulf of California, from northeastern Baja California through southeastern California and southwestern Arizona to western Sonora. It is bounded on the west by the Peninsular Ranges, which separate it from the California chaparral and woodlands and Baja California desert ecoregions of the Pacific slope. To the north, the Sonoran Desert transitions to the cold-winter Mojave, Great Basin, and Colorado Plateau deserts. To the east, the deserts transition to the coniferous Arizona Mountains forests and Sierra Madre Occidental forests at higher elevations. The Sonoran-Sinaloan transition subtropical dry forest marks the transition from the Sonoran Desert to the tropical dry forests of Sinaloa.

The desert's sub-regions include the Colorado Desert and Yuma Desert. In the 1951 publication, Vegetation of the Sonoran Desert, Forrest Shreve divided the Sonoran Desert into seven regions according to characteristic vegetation: Lower Colorado Valley, Arizona Upland, Plains of Sonora, Foothills of Sonora, Central Gulf Coast, Vizcaino Region, and Magdalena Region. (see An Overview of the Sonoran Desert, external link below). Many ecologists now consider Shreve's Vizcaino and Magdalena regions, which lie on the western side of the Baja California Peninsula, to be a separate ecoregion, the Baja California desert. The PBS series Reading Rainbow shot its sixty-second episode Desert Giant: The World of the Saguaro Cactus here on March 27,1990. This book by Barbara Bash was narrated by Philip Bosco.

Ecology

The Sonoran Desert includes 60 mammal species, 350 bird species, 20 amphibian species, 100+ reptile species, 30 native fish species, and more than 2000 native plant species. The Sonoran Desert is considered the wettest desert in the world, receiving up to per year in some locations.

Flora

Many plants not only survive the harsh conditions of the Sonoran Desert, but they actually thrive. Many have evolved to have specialized adaptations to the desert climate. The Sonoran Desert includes such plants from the agave family, palm family, cactus family, legume family, and many others. This desert is the only place in the world where the famous saguaro cactus grows in the wild.

Population

The desert is home to seventeen aboriginal American cultures.

The largest city in the Sonoran Desert is Phoenix, Arizona, U.S.A. This metropolitan area in central Arizona is one of the fastest-growing metropolitan area in the United States, with a population of 4 million. In the North Phoenix area, desert is losing ground to development at a rate of approximately 4,000 m² (1 acre ) per hour. The next largest cities are Tucson, in southern Arizona, U.S.A., with a metro area population of around 900,000, and Mexicali, Baja California, Mexico, whose municipality also has a population of around 900,000. The municipality of Hermosillo, Sonora, Mexico has a population of around 700,000.