This is a reformatted edition of the authors' joint 2006 M.Sc. thesis at the Technical University
of Denmark. Abstract: Urban, industrial and agricultural activities threaten
the groundwater resource that feeds the Sian Ka'an Biosphere Reserve, a UNESCO
World Heritage site on the Caribbean coast of the Yucatan Peninsula, Mexico.
The area has a complex karstic geology with high permeability features, and
the thesis investigates how the water resource dynamics of the catchment that
encompasses the Reserve can best be modelled. A conduit-matrix model has been
found to be appropriate for modelling groundwater flow in the catchment on
a local scale, whereas an equivalent porous medium model is appropriate for
regional scale modelling. High permeability zones have been identified based
on visual inspection of satellite imagery and confirmed using frequency-domain
geophysical measurements. These zones have been incorporated into the model
scenarios and have been found to significantly impact the size of the catchment.
The regional hydrological modelling has shown that a significant potential
threat to the Reserve is posed by the nearby urban and agricultural areas
of Felipe Carrillo Puerto and Andres Quintana Roo, from where pollutants may
be able to reach the Reserve in less than 10 years. Also pollution from more
distant areas may be able to reach the Reserve assuming high permeability
in the identified structures. Moreover, it cannot be excluded that pollution
from the area covered by the proposed development plan for Tulum can spread
to the Reserve. The visual outcomes of the hydrological models is expected
to be valuable inputs to decision making processes concerning the management
of the groundwater resources of the Sian Ka'an catchment in the future.
