Deserts of California - Ecology

Ecology

All of the deserts of California are characterized by low rainfall, caused by the rain shadow of mountain ranges to the west of each desert. The Mojave Desert receives between 3 to 10 inches (76 to 250 mm) of rain per year, while the Colorado Desert receives between 2 to 6 inches (51 to 150 mm).

The Mojave Desert is considered a high desert, because elevations can range up to 11,000 feet (3,400 m). The Mojave Desert is characterized by the presence of Yucca brevifolia, the Joshua Tree, which as an indicator species of the Mojave Desert, extends southeaslerly into Mohave County, Arizona, and even further, all parts of northwest Arizona. Other common plants of the Mojave Desert include creosote bush, blackbrush, greasewood and saltbush. Higher elevations host Western juniper and Pinyon pine.

The Colorado Desert is a low desert, with elevations running from -230 to 1,000 feet (−70.1 to 300 m) above sea level. The Colorado Desert hosts saguaro cactus, Sonoran creosote bush, and Salton Sea saltbush.

The Great Basin desert in California can also reach up to 11,000 feet (3,400 m) of elevation. Plants in the Great Basin Desert are well adapted to the harsh conditions. These plants include Big sagebrush, Pinyon pine, Utah juniper, Low sagebrush, Shadscale, and Bristlecone pine. Sagebrush, a very common resident of the Great Basin, is well adapted to the area. The Big sagebrush root system can extend as much as 90 feet in circumference. This adaptation allows the plant to catch as much water as possible when the rains do come. Mormon tea possesses modified leaves. The leaves are very small and are not the primary area for photosynthesis. The chlorophyll filled stems carry out the primary photosynthesis. Four-wing saltbush excretes salt through its leaves to prevent build-up of lethal salts in the plant. The plants on the alkaline flats have a high internal concentration of salt and are able to extract water other plants can not.

Common animals of the California deserts include the desert bighorn sheep, desert kit fox, coyote, spotted skunk, spotted bat, black-tailed jackrabbit, ground squirrels, kangaroo rat, white-footed mouse, and desert tortoise.