Diurnal Fluctuation in Hydrostatic Level of Petenes on the Northwestern Coast of Yucatan, Mexico: Effects of Dredging and Canalization of Springs

Abstract

As part of reclamation of the El Palmar-Yucatan State Reserve, the impact of dredging the springs in the Elepeten peten (isle with abundant vegetation along the Yucatan coast) and an old canal in the Tzintzin peten on the diurnal fluctuation in the local hydrostatic level are evaluated. Observations were made at various points during four 24-hour cycles of water levels (every hours) and temperature and salinity (every hours). The first three observation periods were before, during and after the dredging of the springs in the Elepeten peten.

During the fourth observation period samples were collected simultaneously at the Elepeten peten and the Tzintzin peten. The observations were made during similar tide levels. Following the dredging of the spring, a rise in the hydrostatic level was recorded at the Elepeten peten resulting in a major flow of water toward the lagoon and a reduction in salinity, especially during high tide. The reopening of the canal at the Tzintzin peten produced a minor hydraulic response of the spring to the tide level and a lowering of the hydrostatic level in the peten. During low tide, there is an influx of lagoon water to the spring, elevating salinity and temperature. The highest hydraulic energy seen in Elepeten after dredging the springs (greater flow of water) was correlated with a higher biotic productive and a high degree of soil formation. However; the lower hydrostatic level at the Tzintzin peten and the corresponding inflow of brackish water to the spring could induce soil erosion and the loss of endemic species. As a result of this study, the authors recommend that the old canals in the petens remain closed and that the canals in the Dzulá, Tzintzin, Lagartero y Bolon petens, opened during the reclamation project, be closed.