Abstract

RODRIGUEZ, Gilberto. El lago de Maracaibo como cuenca anaeróbica natural: Uso de líneas de base históricas en estudios de impacto ambiental. INCI [online]. 2001, vol.26, n.10, pp.450-456. ISSN 0378-1844.

The presence of a hypolemnitic anaerobic cone, maintained by the salinity stratification, and the high productivity, has been proposed as evidence of an advanced eutrophication of Lake Maracaibo. Since salinity has increased with the deepening of the navigation channel, it has been proposed, as a remedial measure, the elimination of the channel and the relocation of shipping facilities to a multiport in the nearby Gulf of Venezuela. The high yield of fisheries (71700 MT/year) and the stability of the catch of indicator commercial species imply that there is not an advanced deterioration of the system. The historic baselines support the alternative hypothesis that the high phytoplanktonic productivity and the presence of an anaerobic zone are natural traits of the Lake that were present prior to the deepening of the channel. The Maracaibo depression is an important oil producing basin, and the anaerobic condition and high production and accumulation of non-degraded organic matter, are characteristics of the processes leading to oil accumulation. Research on the paleoenvironments of the late Quaternary may contribute to strengthen this hypothesis.

Keywords : Sistema de Maracaibo ; Impacto Ambiental ; Eutroficación ; Anoxia .