Contribution
Macroinvertebrate associations in two basins of SW Spain
Gallardo Mayenco, Alfonso
Archiv für Hydrobiologie Volume 127 Number 4 (1993), p. 473 - 483
17 références bibliographiques
publié: Jul 14, 1993
DOI: 10.1127/archiv-hydrobiol/127/1993/473
ArtNo. ESP141012704006, Prix: 29.00 €
Abstract
The aquatic macroinvertebrates that inhabit the headwater of the Guadaíra and Guadalete river basins were sampled during January 1988 and January 1989. In the Guadaíra basin gypsum is quite abundant and makes the water extremely saline, while the Guadalete basin has water with a normal salinity. Most streams of the Guadaíra basin were completely dry during drought (from May until November). In the Guadalete basin, however, most streams discharge throughout the year. During the study we have found seven associations of species. That constituted by Mercuria confusa, Bezzia sp., Helius sp. and Echinogammarus obtusidens is an index of very saline watercourses (up to 19 mS cm-1 of conductivity). Associations formed by Simulium intermedium, S. pseudequinum and Atyaephyra desmarestii; and S. ruficorne, B. lutheri and P. clarkii are representative of very degraded trenches.
Mots-clefs
gypsum • headwater • salinity • Guadaíra • Guadalete • Spain