General Description

The Sonoran Desert is one of the largest protected desert areas in North America and is extremely rich in biodiversity (1). The desert contains every kind of biome due to its western location near 30° north latitude, include: the tundra, coniferous forest, temperate deciduous forest, grassland, chaparral, desert, thornscrub, and tropical forest. The map below represents the vast area the desert covers in green, stretching roughly around 100,000 square miles of land is located in a small part of southeastern California, southern Arizona, the majority of the Baja California Peninsula, and the eastern part of the Mexican state of Sonora (2). The desert in the Baja California area, alone, covers about 30,000 square miles (about one third of the desert), which is mainly dominated by chaparral and tundra biomes (2).

Map of the Sonoran Desert (green)
Baja California Desert (circled in red/the focus of the project)
http://www.nps.gov/cagr/forkids/the-sonoran-desert.htm 

The Sonoran Desert in Baja California
http://tucson-infonet.com/desert.html

Plant Communities in the Baja California (Sonoran) Desert
http://www.biology.ed.ac.uk/archive/jdeacon/desbiome/bajacal1.htm#top 

Historical State of the Ecosystem

The Sonoran Desert has ”diverse vegetation” and is considered to be the most tropical desert in all of North American (2). Because the desert stretches out two four different states in two different countries, it is apparent how distinctive the temperate zones are from each other when passing through each state or area. Historically, the desert did not start off being as large as it nor did the desert contain the same animals and plants that we see today. In fact, it wasn’t until about five or six million years ago that the Baja California Peninsula actually formed, breaking off the mainland of Mexico and becoming surrounded by the Pacific Ocean and the Gulf of California (2). Due to its isolation, the plants and animals that were on the peninsula have become endemic to Baja California in particular (3). Moreover, the desert area in the Baja California Peninsula is even more diverse with plants that are “unique to this region” such as boojum tree and the Baja California rock squirrel (3, 4).

A map of what Mexico would have looked like before
the formation and separation of the Baja California Peninsula.
(About 5-6 million years ago)

According to the Britannica Encyclopedia, the first humans to move to the Baja California Peninsula was around 9,000 to 10,000 years ago, during the time large “Pleistocene mammals roamed the area” (5). Approximately around 1533, there lived 60,000 to 70,000 Indians in the desert area in different groups “exploiting a definite territory for hunting, fishing, and gathering wild plants” (5). After Baja California’s independence from Spain in 1822, the Spanish population began to abandon the area and was left to a small population of “mestizo farmers and cattleman” (5). This was followed by Mexico gaining possession of the peninsula after the Mexican War in 1848 (5). Up to this time, human impact was not severe and the desert remained predominantly intact due to its isolation from the rest of Mexico and having the border separation between the United States and Mexico. It wasn’t until the 1960s that highways, construction, agriculture, mining, and tourism began and has since continued demolishing habitats such as the “mountains ranges, plains, and vast extensions of coastal dunes”, home to various plants and animals (1, 5).

Development of hotel resorts destroying spices'  habitats and land.
http://www.fishinginternational.com/location/MexiLoretoCRLR20060710.htm 

Current Human Impacts

Though the Baja California Peninsula in Mexico is mainly intact and relatively stable, there are certain human impacts that can negatively impact the desert if intensified and/or continued (1). One of the biggest concerns is the intensive agriculture that has converted much of the natural desert land into demolished animal and plant habitats (4). The insecticides and herbicides have been affecting the some of the desert’s native species, such as moths, bees, and native weeds that insects use for nectar (4). Furthermore, agriculture has also been disrupting natural habitats and altering their migration systems due to the change in vegetation (4). According to a study of the impacts of land degradation in the Sonoran Desert, “overgrazing [has caused] severe land degradation” leaving the land with “shorter grasses and more bare soil” (6). The demolishing of ecosystem can and has partly “result in a significant decline of species diversity, loss of vegetation” causing warmer climate than before” (because vegetation is a determinant of the climate in an area) (6). Additionally, grazing animals such as cattle and burros tend to feed on “palatable vegetation” leaving the less desired vegetation produce at a faster pace than the desired vegetation (4).

Agriculture Human Imapact

http://www.biology.ed.ac.uk/archive/jdeacon/desbiome/agricult.htm#top 

Another issue that is still in dispute today is the bordering between California and the Mexican state of Baja California. The Department of Homeland Security of the United States has been adamant about constructing a fence on the border to prevent illegal immigrants from entering the United Sates (7). However, the metal and cement walls that are being constructed disrupt and devastate animal and plant habitats, especially keeping land animals from being able to migrate (7). Aside from the destruction possible from the construction of the wall, the people hoping to cross the border from Mexico to the United States have also had an impact on the environment. Due to the walls, border crosser sometimes create their own routes in order to avoid border patrol, which also “threaten[s] both the landscape and wildlife” (7).

Metal fencing on the US-Mexico boarder and the effects on animal habitats.
(Between California and Mexico)

The human impact and consequences in the Sonoran Desert in
Baja California. 

Future Prospects for this Ecosystem

Although the both Mexico and the United States have actively been working on the planning and preservation of the desert landscape and wildlife, there are issues that will continue to affect the future of the Sonoran Desert. What used to be in isolation is not a vast tourist attractions and construction of new attractions has appealed to more people in areas such as Rosarito and Cabo Pulmo. Due to an increase in popularity, humans have been transforming and will continue transforming sections of the desert into tourist attraction. There is already road construction all across the Baja California Peninsula, which have already demolished much of the environmental habitats in the desert, the highways are continuously subject to renovation. This will undoubtedly cause more destruction and disruption on the land and it’s wildlife (8). 

Highway construction across the peninsula in which some
areas are subject to renovation (while others are just developing).

Road construction in Baja California Desert.
http://www.bajagoodlifenews.com/2012/02/baja-highway-construction-update.html 

Mining and grazing are other potential future issues that threaten the Sonoran Desert. “It is the tearing up of the land and exporting the natural resources from the earth” that will leave the desert with “damaged soil and contaminated water” (7). If these issues continue in its intensity, the ecosystem is in danger of losing its endemic wildlife because of the environmental destruction. Although some of the mining has been closed down before, the people living in those regions underwent an extreme period of job loss and thus, had to be opened once again (7). Unless Mexico is able to find new environmentally friendly jobs for people in these regions, mining will continue to tear up the land and it’s species (7).

Mining in Baja California: Devastation of animal habitat and
tearing of the land.
http://www.sandiegoreader.com/users/photos/2012/oct/26/34409/