| Title | First phase of macroinvertebrate repopulation of Lake Orta (Buccione Basin) after liming. |
| Abstract | The research described here was performed during 1993 and 1994 in the context of studies on the recovery of Lake Orta from acidification after the liming conducted from May 1989 to June 1990. The causes of the pollution were due to the oxidation of ammonium sulphate discharged from a factory producing rayon by a cupro-ammoniacal method and to the loads of heavy metals (Cu, Cr, Ni, Zn) derived from plating factories. One year after liming, an increase in pH and a marked decrease in metal concentrations were observed, and as a consequence some qualitative and quantitative changes were observed in 1992-93 in the planctonic communities and in the littoral macrobenthic fauna. This paper presents qualitative and quantitative data on macrobenthos collected along a transect between the littoral and the maximal depth in the Buccione Basin, which was directly affected by the effluents of the rayon factory. The data revealed some quantitative repopulation of this community, especially along the littoral. Qualitatively, however, the macrobenthos was still quite poor, consisting essentially of Oligochaeta and Diptera Chironomidae. The former were rare and mainly represented by Naididae between 15 and 22 m, while the Tubificidae were well represented in the littoral and the profundal zones. As regards the Chironomidae, the genera Procladius and Chironomus gr. thummi extended as far as the maximum depth, while others, such as Ablabesmyia, Parakiefferiella bathophila and Dicrotendipes gr. nervosus were mostly distributed in the littoral layers. Among the other taxonomic groups only the Trichoptera and the Diptera Ceratopogonidae were quantitatively significant. However, many systematic entities typical of the less polluted Italian subalpine lakes are still absent. In fact, the colonisation of Lake Orta by macrobenthic organisms is still influenced by the increased concentrations of heavy metals in the sediment precipitated from the water column. The research included analysis of lake water and sediments chemistry to obtain information on the trophic level of the environment. |
| Source | Journal of limnology (Testo stamp.) 60 (1), pp. 110–126 |
| Keywords | Ortaacidificationlimingmacroinvertebrate community |
| Journal | Journal of limnology (Testo stamp.) |
| Editor | Istituto per lo Studio degli Ecosistemi., Verbania Pallanza, Italia |
| Year | 2001 |
| Type | Articolo in rivista |
| Authors | Nocentini, Anna Maria; Boggero, Angela; De Margaritis, Giovanna; Gianatti, Marcella |
| Text | 353310 2001 ISI Web of Science WOS BCI200300001344 Orta acidification liming macroinvertebrate community First phase of macroinvertebrate repopulation of Lake Orta Buccione Basin after liming. Nocentini, Anna Maria; Boggero, Angela; De Margaritis, Giovanna; Gianatti, Marcella CNR Istituto Italiano di Idrobiologia, Largo Tonolli 50, 28922, Verbania Pallanza, Italy The research described here was performed during 1993 and 1994 in the context of studies on the recovery of Lake Orta from acidification after the liming conducted from May 1989 to June 1990. The causes of the pollution were due to the oxidation of ammonium sulphate discharged from a factory producing rayon by a cupro ammoniacal method and to the loads of heavy metals Cu, Cr, Ni, Zn derived from plating factories. One year after liming, an increase in pH and a marked decrease in metal concentrations were observed, and as a consequence some qualitative and quantitative changes were observed in 1992 93 in the planctonic communities and in the littoral macrobenthic fauna. This paper presents qualitative and quantitative data on macrobenthos collected along a transect between the littoral and the maximal depth in the Buccione Basin, which was directly affected by the effluents of the rayon factory. The data revealed some quantitative repopulation of this community, especially along the littoral. Qualitatively, however, the macrobenthos was still quite poor, consisting essentially of Oligochaeta and Diptera Chironomidae. The former were rare and mainly represented by Naididae between 15 and 22 m, while the Tubificidae were well represented in the littoral and the profundal zones. As regards the Chironomidae, the genera Procladius and Chironomus gr. thummi extended as far as the maximum depth, while others, such as Ablabesmyia, Parakiefferiella bathophila and Dicrotendipes gr. nervosus were mostly distributed in the littoral layers. Among the other taxonomic groups only the Trichoptera and the Diptera Ceratopogonidae were quantitatively significant. However, many systematic entities typical of the less polluted Italian subalpine lakes are still absent. In fact, the colonisation of Lake Orta by macrobenthic organisms is still influenced by the increased concentrations of heavy metals in the sediment precipitated from the water column. The research included analysis of lake water and sediments chemistry to obtain information on the trophic level of the environment. 60 Published version Minverts Orta 2001_Nocentinietal_Orta_JLimnol 0.pdf Articolo in rivista Istituto per lo Studio degli Ecosistemi. 1129 5767 Journal of limnology Testo stamp. Journal of limnology Testo stamp. J. limnol. Testo stamp. Journal of limnology. Testo stamp. angela.boggero BOGGERO ANGELA |
