Caracterización química y faunística de canales de drenaje del valle inferior del Río Colorado (Partido de Villarino y Patagones, provincia de Buenos Aires)

Resumen

This is a contribution to the study o f the salty soil degradation, produced by outcrop of underground salt water, in the Lower Colorado River Valley. The process is made worse by the excesive growth of submerged aquatic weeds in the drainage System. The macroscopic aspect of the problem is shown in a nonquatizated flow diagram.

On the basis of fortnightly water analysis, main chemical features of four principal channels are reported. For each month and channel Schoeller’s graphs are added and ionic variation through the year is pointed out.

The meiofauna related to aquatic weeds was identified and some observations on alimentary habits were made. Bafon-benthos complex is a low diversity community with unispecific dominance of the gastropod Littorina parchappii (Hydrobiidae). Trophic relationships of this fauna are graphically displayed.

The lack of an effective predation on weeds may be a factor of their exuberant development and the introduction of the macrophytophagous snail Ampollaría canaliculata Lamarck, 1801, as a potential biocontrol agent, is proposed.