Distribución altitudinal de especies de Trichoptera en un sistema fluvial en Patagonia

MISERENDINO, M. L

ECOLOGÍA AUSTRAL

Revista de la ASAE

Lugar: Buenos Aires; Año: 1999 p. 28 - 34

0327-5477

Altitudinal zonation studies of Trichoptera species carried out in lotic environments of temperate zones of the Northern Hemisphere, suggest that their diversity and distribution is mostly determined by thermal change as function of the altitude. The objective of this work was to analyse, during a complete annual cycle, distribution patterns of the species of caddis flies in a mountain fluvial system in Patagonia. The system exhibited a 1000 m gradient of height and in the middle was affected by waste discharges. Seventeen species of Trichoptera were identified. Smicridea sp., Mastigoptila longicornuta, Parasericostoma ovale, Neoatopsyche sp., Brachisetodes major y Cailloma sp. were the more extensive distributed species, while the other species had more localised records. The most abundant species were Smicridea sp. and Parasericostoma ovale. Correlation coefficients were obtained between density species and environmental factors after that Caconical correspondence analysis was performed. Environmental variables explained part of the variability of the species. All trophic guilds were recorded, that suggest  exploitation of different resources to diminish the interespecific competition. This last and the environmental heterogeneity could be explaining the high specific richness found.