Urban expansion and change of land uses: city of Mexicali 1990-2005

Mexicali has an important economic role within the state of Baja California, Mexico, and its urban economic dynamic has been a central piece of regional development in the Mexicali valley. This has produced a rapid urbanization of the rural-urban interface, which has intensified energy, material and population exchanges between the central city and its hinterlands. Such a dynamic has produced urban sprawl and a fast restructuring of the urban regional spatial development. Thus, the purpose of this paper is to analyze the spatial dynamics of the rural-urban interface of Mexicali, from 1990-2005. Urban spatial expansion was analyzed by satellite images, LANDSAT TM5 and LANDSAT ETM7 taken in the dry season, to identify land use changes and the physical expansion of the urban area over the last 15 years. Results have showed that Mexicali's urban area has expanded by around 32 km(2), which means an increase of 34% during this period. Meanwhile small cities located in the hinterlands have experienced lower rates of population growth and physical expansion. Some small cities have been absorbed and others have developed over urban corridors to the central city. Changes in spatial patterns of urban structure have been accompanied by the evolution of urban functions and special interactions between the central city and its hinterlands. Lastly, the urbanization process is still in progress, but there are also evidences of urban sprawl in the hinterlands.