Degradación ambiental por procesos de cambios de uso y cubierta del suelo desde una perspectiva espacial en el estado de Guanajuato, México

• Autores: Azucena Pérez Vega, Héctor Hugo Regil García, Jean François Mas
• Localización: Investigaciones geográficas, ISSN 0188-4611, ISSN-e 2448-7279, Nº. 103, 2020
• Idioma: español
• Títulos paralelos:
  • Environmental Degradation from Land-Cover and Use Change Processes from a Spatial Perspective in the State of Guanajuato, Mexico
• Enlaces
  • Texto completo
• Resumen
  • español

    Se analizaron los cambios de cubierta/uso del suelo en el estado de Guanajuato identificando los procesos de transformación y degradación ambiental. El análisis consideró tres periodos de tiempo 2002-2007, 2007-2011 y 2011-2014 basados en la cartografía de uso del suelo y vegetación de INEGI. Se utilizaron métodos de evaluación de tasas de cambio, intensidad de cambio y las secuencias temporales de las cubiertas del suelo. Los mayores porcentajes de intensidad de cambio los presentaron ecosistemas de ambientes áridos y caducifolios como los Mezquite (-3.6%), Selva Baja Caducifolia (-2.1%) y Bosque de encino (-1.4%). La deforestación se redujo a la mitad entre el primer y el último periodo afectando los piedemontes y lomeríos. La mayor intensidad ocurrió durante 2002-2007, seguida de una fuerte reducción en 2007-2011 y finalmente de 2011-2014 un incremento importante de la dinámica sin alcanzar la intensidad del primer periodo. Las trayectorias de cambio no fueron uniformes ni en el tiempo, ni entre categorías. Las cubiertas antrópicas de mayor tasa anual relativa de ganancia fueron los asentamientos humanos establecidos sobre suelos fértiles, así como los pastizales inducidos. Las agriculturas de temporal y riego mostraron muy bajas tasas de cambio relativo pero muy altas tasas de cambio absoluto, entre ellas mantienen secuencias circulares íntimamente ligadas a la disponibilidad de agua subterránea. Existe una estrecha relación entre el abatimiento de los acuíferos y el incremento de la superficie de agricultura de riego, la cual ocupa el 80% del agua subterránea extraída en el estado de Guanajuato.

  • English

    The present study analyzed land cover/use changes in the state of Guanajuato by identifying transformation and environmental degradation processes since it is one of the states with the largest transformed area since colonial times. It has an extensive plain in the southern portion of vertisols soils, considered the most productive soils in the country.The present work addressed the transformations of land cover in the state of Guanajuato, analyzing three time periods of INEGI land-use and vegetation mapping; 2002-2007, 2007-2011, and 2011-2014. We used methods to assess rates of change, intensity of change, and the trajectories of the change sequences of land covers. The highest annual rates of relative loss and percent intensity of change occurred in arid and deciduous ecosystems such as Mezq -3.6%, VSA SBC -2.1%, BQ -1.4, VSA Mezq -1.3% and Pz nat -1.0% in the first and -1.1% in the third periods, with a sequence of change toward Agri t and Pz ind established on foothills and hills.The main intensities of change at the interval level occurred during 2002-2007. The anthropic covers with the highest relative annual rate of profit were AH and Pz ind with 1.5%; AH showed very high values of 5.4%, 4.9%, and 11.2% for each period, replacing considerable areas of Agri r on fertile plains land. Agri t and Agri r showed very low percentages of relative rates of change but very high absolute rates of change during the period 2002-2007. A new area of Agri r was developed during this period to the northeast of the municipality of Dolores Hidalgo and southwest of San Luis de la Paz, coinciding with a high subterranean water reduction of up to 152 m. The sequences of change between Agri t to Agri r, later returning to Agri t in some cases, are intimately linked to the availability of groundwater that supplies up to 80% water for irrigation agriculture in the state of Guanajuato.  Agri r decreased in area for the last two periods and Agri t loss area in the last period.Deforestation processes take place on foothills and hills; these have not decreased considerably, as still represent less than half between the first and last periods. Degradation represents more than half of the area in the same periods.Unfortunately, vegetation recovery processes were reduced three-fold between the last and first periods; these processes developed in foothills and hills, as well as in plains with smaller surfaces.The state of Guanajuato is acknowledged for having a healthy economy, ranked seventh at the national level; however, the environmental cost has been high, as it is one of the states with the largest transformed cover. The results of this study suggest that this trend will continue, posing a threat to the remnants of current ecosystems given the demand for environmental services to produce supplies for the growing local, national, and even international populations.