Streamflow Response to Land-cover Change in Southern Mexico: Projections of Water Balance in the Tulija River Watershed

Open Access
Author:
Garcia-gonzalez, Susana Elizabeth
Graduate Program:
Civil Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
May 07, 2015
Committee Members:
  • Christopher J Duffy, Thesis Advisor
  • Alfonso Ignacio Mejia, Thesis Advisor
  • Kirk Dow French, Thesis Advisor
Keywords:
  • Hydrologic modeling
  • SWAT
  • land-use change
  • Chiapas
  • Mexico
  • tropical forest
  • time series analysis
Abstract:
Vegetation plays a crucial part in the water distribution within watersheds, as the type and extension of land cover influences the interaction of complex spatio-temporal hydrologic processes. Hydrologic simulations have been previously used to quantify the hydrologic response of a watershed to different land cover scenarios. In this study the SWAT model has been applied to expand the understanding of the net effect of land cover change in the northern portion of the state of Chiapas in southeastern Mexico. As a first step a statistical analysis was performed for climatologic and streamflow records of the watershed. Then the SWAT model was calibrated and validated for watershed streamflow records. Later the model was applied to changing land-cover under future climate data generated over the next 60 years. The model performance was verified using standard metrics such as Nash-Sutcliffe efficiency coefficient, bR2, and percent bias. The impact of land cover change on the monthly and annual water balance was consistently proven by the model. The decrease of forested land significantly decreased monthly streamflow for dry months, and increased the maximum streamflow during wet months. The results from this study do not account for local climate and geomorphology feedback; however, it highlights the importance of the incorporation of land management practices in local development plans.