ABSTRACT
In the Yucatan Peninsula the lagoons are the major geomorphological features of the coast. The shallow water (< 2.5 m) of these ecosystems favors coverage of submerged aquatic vegetation (SAV) dominated by seagrasses. The hydrological characteristics of Chelem Lagoon were modified as a consequence of the reduction of freshwater discharge through the springs. Due to harbor and road construction and natural events such as hurricanes, seagrasses almost disappeared and the benthos was occupied by macroalgae. Mean salinity was 42‰ and the SAV coverage, reduced to 20-30‰, was dominated by
Laurencia microcladia, Batophora oerstedii, Acetabularia
sp. In 1994 a hydrological restoration program was initiated, specifically targeting the removal of sediments in the springs thereby increasing freshwater discharges to the lagoon. After 5 years of restoration effort, the mean salinity dropped from 42‰ to 35‰, and the SAV coverage increased to 80%, dominated by
Halodule wrightii
with patches of
Ruppia maritima
and
Thalassia testudinum
.
