Environmental Issues in the Desert Biome

Deserts may seem harsh and inhospitable, but in reality, they contain a fragile ecosystem of plants and animals specially adapted to thrive under these conditions. In some cases, the balance of life is so fragile that one unusually dry or wet season can lead to massive changes. This environmental sensitivity means that deserts face many threats, both from human activity as well as from natural climate cycles.

Climate Patterns

Natural weather variability can drastically alter the temperatures and amount of rainfall of any given region. For example, an El Nino pattern in the Pacific can lead to wet winters, bringing lots of rainfall to the deserts of the South American continent. La Nina, on the other hand, tends to bring drought during the same period. As these patterns become extreme or repeat themselves multiple years in a row, the changes to normal rainfall patterns can cause a disruption in the ecosystem of the desert, reducing the number of plants and animals able to thrive away from permanent water sources.

Climate Change

Climate change affects the desert just as it affects every other biome. Deserts around the world have been warming at a rate of 0.2-0.8 degrees Celsius every decade, compared to an average global increase of 0.45 degrees Celsius during the same period. A rise in desert temperatures can dry out plants, making them more vulnerable to wildfires, or they might simply die due to a lack of moisture. Likewise, the animals that make the desert their home may not be able to cope with the increased temperatures, limiting their range or forcing them to migrate to cooler regions. During the 20th century, much of the Sahel region adjacent to the Sahara desert suffered desertification, greatly changing the makeup of plant and animal life in the area.

Environmental Degradation

Deserts can also suffer from land degradation from a variety of sources. Temperature or rainfall changes that cause vegetation to die out can increase erosion as the roots that hold soil together crumble away. Agriculture using artificial fertilizers in and near the desert can increase the minerals in the soil or change soil chemistry, making it more difficult for plants and animals to thrive in affected regions. Over time, these effects can render near-desert regions into high desert and make the driest areas all but inhospitable to any kind of life. During the 1930s, the great plains of the United States suffered desertification, creating the "Dust Bowl, " as a result of years of drought and poor agricultural techniques.

Human Development

Human habitats represent another major threat to desert areas. Expansion of cities and towns into desert regions can displace animals and destroy plants, especially since these developments tend to focus around sources of water where other living things would naturally thrive. Since human settlements require large amounts of water to thrive, this reduces the amount available to other living things, and it may drive species away or cause local extinctions due to a lack of resources. For instance, Pima County, Arizona is home to 23 threatened or endangered species, and many are at risk due to the destruction or depletion of their natural habitats.