Empirical-based hydrologic modeling of the 100-year return period of overland flow in the Rio Grande watershed, Tlalchapa, Guerrero, using two land use scenarios.

摘要

This study addresses the need for research in the dynamics of land use in the watershed with the aim of confirming an increase in the maximum discharge over time because of the recurring destruction of the main bridge that communicates the town of Villa Madero with its municipal seat, Tlalchapa, Guerrero, caused by unrecorded historical rainfall. The methodology consisted, initially, of determining land use with the supervised classification technique in a 1973 Landsat satellite image, and by screen digitizing over a very high spatial resolution 2006 QuickBird image. The empirical hydrologic model of the rainfall-runoff process in the watershed was constructed with the HEC-HMS system for the 1973 and 2006 scenarios. The principal parameters used in the model were: (1) Type II synthetic storm; (2) the weighted N by sub-basin, created by the US Soil Conservation Service (SCS). With the model we calculated the discharge hydrograph for the watershed. Although a change in cover was detected (forested to grassland) there were no differences in the number (51.55 in 1973 and 57.87 in 2006) or in the maximum calculated discharge for the two scenarios (431 m3 s-1 in 1973 and 484 m3 s-1 in 2006).