Natural Environment Reference

The geologic process in which the surface of the earth, including soil, bedrock, and rock fragments, is degraded by natural processes. There are multiple processes by which these earth materials can be eroded including eolian erosion (wind), fluvial (rivers and streams), marine (ocean waves), and glacial. These processes break down rocks in their primary locations and then transport them to secondary locations. Geologic formations such as canyons and mesas are formed by the erosion of bedrock by natural forces. Erosion in the Southwest, in addition to many regions around the planet, has been exacerbated by human impact, such as overuse of sensitive areas; extraction of natural resources, inlcuding water; and land management practices at a large scale.

There are over 200 species of owl, a mostly nocturnal bird of prey found on almost every continent. Owls eat small rodents, insects, and other birds. Their acute powers of vision, strong sense of hearing, and silent flight all contribute to their reputations as formidable hunters.

Some cultures traditionally avoid owls, as they are believed to foretell the passing of a loved one. Additionally, as in the case of the Navajo, owls are believed to be inhabited by the ghosts of the dead, thereby causing ghost sickness in those they encounter.

Runoff occurs when water from snowmelt or rain runs along the surface of the earth without being absorbed into the soil. Over time, runoff contributes to erosion. In large amounts, runoff can cause flooding.

The wood mouse, known scientifically as genus Apodemus, is a small burrowing rodent that is native to Europe and Africa. The equivalent mouse species common to the Southwestern U.S. and northern Mexico is commonly referred to as the desert pocket mouse (genus Chaetodipus), whose preferred habitat is sandy, sparsely vegetated desert environments. It is primarily nocturnal and solitary, and burrows in small apertures in the ground for purposes of refuge, seed storage, and to care for its young.

Sagebrush, often shortened to "sage," is the name of a group of plants that are commonly referred to as sagebrushes or sageworts. These are plants in the genus Artemisia, a large genus in the daisy and ragweed family, and are often used as a culinary herb or tea in different cultures around the world. The sagebrush that is native to the American Southwestern regions is a low-growing bush that is characterized by its grayish-green color and aromatic leaves.

Sagebrush is widely used in various Native American ceremonies, and is thought to have cleansing and healing properties. Traditionally, sage leaves are dried and tied into bundles that in English are called "smudge sticks." when the end of the smudge stick is lit and allowed to smolder, the dried, tightly-bound sage leaves burn slowly like incense, producing thick smoke that is believed to act as an energy cleanser and protector for a person or a dwelling place.

A flowering shrub (Gutierrezia sarothrae) found in the western half of the United States, often growing in arid grasslands or on mountain sides. This flowing plant is perennial, meaning it grows for more than two years. Often perceived as a weed, snakeweed can be mistaken for Rabbitbrush, which does not flower. Snakeweed can be toxic to sheep if eaten in great amounts; however, American Pronghorn prefer this shrub for browsing.

Snakeweed is often used for medicinal purposes by various Native American tribes. For instance, the Navajo use the ashes of this shrub to relieve dizziness and headaches and use chewed snakeweed on insect stings to reduce swelling and irritation. The Lakota use this plant as a horse laxative. Snakeweed is also used for Navajo ceremonials and chants. In the Mountain Chant Ceremony, for example, snakeweed is burned to charcoal, along with other shrubs, and used to cover the body of the patient. Snakeweed can also be used as an emetic, something that causes vomiting, in night ceremonials and to help deliver the placenta after childbirth.

Also known as an anvil cloud, a thunderhead is the towering head of a cumulus cloud that is moving in the direction of high winds aloft. A thunderhead usually signals the imminent potential of downbursts of heavy rain accompanied by violent winds.

The piñón or pinyon, is a type of pine tree that is native to the American Southwest and is common in the woodlands of Colorado, New Mexico, Arizona, Utah, Nevada, and California. The pinyon pine is a relatively short tree that does not usually grow over 20-50 feet. It is characterized by its rounded form and branches that extend outward. The tree grows very slowly, reaching maturity around 100 years, and on average lives to be 350-450 years old. Pinyon pines produce edible pine nuts that have been a major food source for Native American peoples for centuries, and the tree's timber was used in early pueblo and cliff dwelling structures. The pinyon pine is known as the official state tree of New Mexico..

The ancestor of modern dogs, a wolf is a carnivorous mammal that walks on all fours and hunts in groups known as packs. There are three species of wolves: Canis lupus (gray/timber wolf), Canis rufus (red wolf), and Canis simensis (Abyssinian wolf). Wolves are found throughout the Northern Hemisphere and are members of the family Canid.

In the Southwest there used to be a subspecies of the gray wolf, the Mexican gray wolf (Canis lupus baileyi). They were hunted out of existence in the wild in the 1970s, and the only surviving wolves were in zoos. In 1998, U.S. Fish and Wildlife Service introduced eleven Mexican gray wolves back into the wild and now the subspecies is slowly growing in number.

A layer of the earth’s atmosphere above the troposphere and just below the mesosphere. This layer is stratified, with the upper layers being much warmer than the lower levels. At the earth's surface, on the other hand, temperature decreases with altitude. One of the reasons that the upper reaches of the stratosphere are warmer than the lower reaches is because the stratosphere also includes the ozone layer, which is composed of a type of oxygen molecule by the same name. The ozone layer traps ultraviolet rays from the sun, causing a chemical reaction that releases small, yet incrementally cumulative, amounts of heat, thereby providing a protective thermal layer for the earth.