Abstract

FIGUEROA-JAUREGUI, M. Lourdes et al. Land use change in San Cristobal de las Casas watershed, México. Agrociencia [online]. 2011, vol.45, n.5, pp.531-544. ISSN 2521-9766.

Similar to what occurs with the forests of other tropical zones, the forest surface in some regions of the Chiapas Highlands has been reduced by nearly half since 1970. Therefore, an analysis was made of land use change and its effects on the degradation processes and the hydrological processes in the endorheic watershed of San Cristobal de las Casas, in the Chiapas Highlands, México. The land uses of the watershed were obtained through the supervised classification of Landsat satellite images of 1975, 1993 and 2000, and Spot of 2009. The annual rate of water erosion was calculated with the Universal Soil Loss Equation (USLE), and the mean annual runoff volume by the indirect method of rainfall-runoff of the norm NOM-011-CNA-2000, for the four years of study. Five uses were identified in the watershed: rainfall agriculture (RA), oak forest (OF), pine forest (PF), cloud forest (CF) and urban zones (UZ). A marked tendency of change of surface in RA was not observed, but in units of OF and CF there was a reduction from 1975 to 1993 and 2000, whereas the urban zones showed a tendency of growth for the four years of study. The water erosion levels were affected from 1975 to 2000, due to the loss of forest cover and the increase of agricultural and urban zones in this period. The volumes of annual runoff tended to increase: 76.85 million m³ in 1975; 78.12 in 1993; 79.48 in 2000 and 82.0 in 2009.

Keywords : water erosion; mean annual runoff; land use.