Scheda di dettaglio – i prodotti della ricerca
| Dato | Valore |
|---|---|
| Title | Taxonomic and functional homogenisation of macroinvertebrate communities in recently intermittent Alpine watercourses |
| Abstract | Mountain streams in southwestern European Alps are currently shifting from perennial to intermittent flow due to the combined effects of climate change and local anthropogenic pressures. Given that flow intermittency is a recently documented phenomenon in the Alps, only scattered studies have investigated functional and taxonomical diversity of benthic invertebrate communities in recently intermittent Alpine streams. We used a hierarchical sampling design to investigate patterns in taxonomic and functional diversity of benthic invertebrate communities in 13 recently intermittent Alpine streams in north-west Italy. in April 2017, we sampled benthic communities in two reaches of each stream with different hydrological conditions: a control reach, with permanent flow; and an intermittent reach, which recently experienced non-flow periods in summer. We tested for the response of taxonomic richness at multiple spatial scales by partitioning total diversity into the average richness of local communities and the richness due to variation among local communities both within and among reaches. By partitioning total diversity (?) into its local (?) and turnover (?) components we showed a decrease in local and regional species richness both within and among reaches, whereas variation among communities was significantly lower in intermittent reaches at the reach scale only. The analysis of multidimensional trait space of macroinvertebrate communities in reaches with different hydrological conditions revealed a significant reduction of functional diversity, dispersion, and evenness in intermittent reaches. There was trait overdispersion in intermittent reaches, as these hosted both typical Alpine taxa and organisms adapted to flow intermittency. In particular, we observed the replacement of taxa with aquatic respiration and those preferring medium- to fast-flowing oligotrophic waters by taxa adapted to lentic habitats, air breathing and with larval dormancy phases. These results indicate that recent flow intermittency has caused drastic changes in benthic invertebrate communities in Alpine streams. Our work highlights the importance of integrating taxonomic and functional diversity to thoroughly assess the impacts of flow intermittency. |
| Source | Freshwater biology (Print) |
| Keywords | diversity partitioningdryingflow intermittencyfunctional traitsnestedness |
| Journal | Freshwater biology (Print) |
| Editor | Blackwell Scientific Publications., Edinburgh, Regno Unito |
| Year | 2020 |
| Type | Articolo in rivista |
| DOI | 10.1111/fwb.13605 |
| Authors | Piano, Elena; Doretto, Alberto; Mammola, Stefano; Falasco, Elisa; Fenoglio, Stefano; Bona, Francesca |
| Text | 434282 2020 10.1111/fwb.13605 Scopus 2 s2.0 85089870791 diversity partitioning drying flow intermittency functional traits nestedness Taxonomic and functional homogenisation of macroinvertebrate communities in recently intermittent Alpine watercourses Piano, Elena; Doretto, Alberto; Mammola, Stefano; Falasco, Elisa; Fenoglio, Stefano; Bona, Francesca Consiglio Nazionale delle Ricerche; Universita degli Studi di Torino; Universita degli Studi del Piemonte Orientale Amedeo Avogadro ; ALPSTREAM Mountain streams in southwestern European Alps are currently shifting from perennial to intermittent flow due to the combined effects of climate change and local anthropogenic pressures. Given that flow intermittency is a recently documented phenomenon in the Alps, only scattered studies have investigated functional and taxonomical diversity of benthic invertebrate communities in recently intermittent Alpine streams. We used a hierarchical sampling design to investigate patterns in taxonomic and functional diversity of benthic invertebrate communities in 13 recently intermittent Alpine streams in north west Italy. in April 2017, we sampled benthic communities in two reaches of each stream with different hydrological conditions a control reach, with permanent flow; and an intermittent reach, which recently experienced non flow periods in summer. We tested for the response of taxonomic richness at multiple spatial scales by partitioning total diversity into the average richness of local communities and the richness due to variation among local communities both within and among reaches. By partitioning total diversity into its local and turnover components we showed a decrease in local and regional species richness both within and among reaches, whereas variation among communities was significantly lower in intermittent reaches at the reach scale only. The analysis of multidimensional trait space of macroinvertebrate communities in reaches with different hydrological conditions revealed a significant reduction of functional diversity, dispersion, and evenness in intermittent reaches. There was trait overdispersion in intermittent reaches, as these hosted both typical Alpine taxa and organisms adapted to flow intermittency. In particular, we observed the replacement of taxa with aquatic respiration and those preferring medium to fast flowing oligotrophic waters by taxa adapted to lentic habitats, air breathing and with larval dormancy phases. These results indicate that recent flow intermittency has caused drastic changes in benthic invertebrate communities in Alpine streams. Our work highlights the importance of integrating taxonomic and functional diversity to thoroughly assess the impacts of flow intermittency. Published version http //www.scopus.com/record/display.url eid=2 s2.0 85089870791 origin=inward Articolo in rivista Blackwell Scientific Publications. 0046 5070 Freshwater biology Print Freshwater biology Print Freshw. biol. Print stefano.mammola MAMMOLA STEFANO |