Scheda di dettaglio – i prodotti della ricerca
| Dato | Valore |
|---|---|
| Title | Long-Term Changes in the Zooplankton Community of Lake Maggiore in Response to Multiple Stressors: A Functional Principal Components Analysis |
| Abstract | We describe the long-term (1981-2008) dynamics of several physico-chemical and biological variables and how their changes may have influenced zooplankton structure in Lake Maggiore (Italy). Data was available for the 1981-1992 and 1995-2008 periods. Standardized time-series for temperature and total phosphorus (TP), chlorophyll-a, phytoplankton density (cel m(-3)), and cell size (mu m(3)), as well as zooplankton structure (Copepoda, Cladocera, and Rotifera density, ind m(-3)) were smoothed using penalized B-splines and analyzed using Functional Principal Components (FPCs) to assess their dominant modes of variation. The first four FPCs explained 55% of 1981-1992 and 65% of 1995-2008 overall variation. Results showed that temperature fluctuated during the study period, particularly during 1988-1992 with a general tendency to increase. TP showed a declining trend with some reversions in the pattern observed in the years 1992, 1999, and 2000. Phytoplankton estimators and chlorophyll-a concentration showed a variable trend along the study period. Zooplankton groups also had a variable trend along the study period with a general increase in density of large carnivorous (mainly Bythotrephes longimanus) and a decrease of large herbivorous (mainly Daphnia), and a similar increase in the ratio of raptorial to microphagous rotifers. Our results suggest that the lake experienced a strong trophic change associated with oligotrophication, followed by pronounced climate-induced changes during the latter period. TP concentration was strongly associated with changes in abundance of some zooplankton taxa. |
| Source | Water (Basel) 11 (5) |
| Keywords | B-Splines smoothingFunctional Data Analysislimnologymonitoring ecological dynamicsoligotrophicationzooplanktonphytoplankton |
| Journal | Water (Basel) |
| Editor | Molecular Diversity Preservation International, Basel, |
| Year | 2019 |
| Type | Articolo in rivista |
| DOI | 10.3390/w11050962 |
| Authors | Arfe, Andrea; Quatto, Piero; Zambon, Antonella; MacIsaac, Hugh J.; Manca, Marina |
| Text | 420978 2019 10.3390/w11050962 ISI Web of Science WOS 000472680400092 B Splines smoothing Functional Data Analysis limnology monitoring ecological dynamics oligotrophication zooplankton phytoplankton Long Term Changes in the Zooplankton Community of Lake Maggiore in Response to Multiple Stressors A Functional Principal Components Analysis Arfe, Andrea; Quatto, Piero; Zambon, Antonella; MacIsaac, Hugh J.; Manca, Marina Bocconi Univ; Univ Milano Bicocca; Univ Milano Bicocca; Univ Windsor; CNR We describe the long term 1981 2008 dynamics of several physico chemical and biological variables and how their changes may have influenced zooplankton structure in Lake Maggiore Italy . Data was available for the 1981 1992 and 1995 2008 periods. Standardized time series for temperature and total phosphorus TP , chlorophyll a, phytoplankton density cel m 3 , and cell size mu m 3 , as well as zooplankton structure Copepoda, Cladocera, and Rotifera density, ind m 3 were smoothed using penalized B splines and analyzed using Functional Principal Components FPCs to assess their dominant modes of variation. The first four FPCs explained 55% of 1981 1992 and 65% of 1995 2008 overall variation. Results showed that temperature fluctuated during the study period, particularly during 1988 1992 with a general tendency to increase. TP showed a declining trend with some reversions in the pattern observed in the years 1992, 1999, and 2000. Phytoplankton estimators and chlorophyll a concentration showed a variable trend along the study period. Zooplankton groups also had a variable trend along the study period with a general increase in density of large carnivorous mainly Bythotrephes longimanus and a decrease of large herbivorous mainly Daphnia , and a similar increase in the ratio of raptorial to microphagous rotifers. Our results suggest that the lake experienced a strong trophic change associated with oligotrophication, followed by pronounced climate induced changes during the latter period. TP concentration was strongly associated with changes in abundance of some zooplankton taxa. 11 Published version Articolo in rivista Molecular Diversity Preservation International 2073 4441 Water Basel Water Basel Water Basel Water. Basel marinamarcella.manca MANCA MARINA MARCELLA |