| Title | Reframing Lake Geneva ecological trajectory in a context of multiple but asynchronous pressures |
| Abstract | Regime shifts are major reorganization of ecological processes, creating new sets of mechanisms that drive the new ecological regime. Such rearrangements can affect how and how much the system responds to pressures other than those that created the shift (interactive carryover). Lake Geneva still exhibits high levels of productivity despite reductions in phosphorus to its reference baseline; the continued high productivity is likely due to the synergistic effects of climate change. We tested whether the contemporary Lake Geneva plankton community response to air temperature, one symptom of climate change, differed from the responses to past changes in air temperature. We used paleoecology to quantify the changes in plankton communities, as a proxy of general ecological changes, over the past 1500 years. Our results show that from 563 AD (beginning of the record) to the twentieth century, the cladoceran assemblage remained stable, despite climate variability of 3 °C in air temperature. The plankton community of Lake Geneva appeared to shift for the first time in the 1500 year record in 1946, and dynamic linear models suggested that 1958-1961 was a critical transition period when the ecosystem changed state. Littoral species were lost, and the assemblage became dominated by pelagic species. The shift took place around the beginning of the current long-term monitoring program, when local perturbations (eutrophication) were escalating. Our results suggest that eutrophication acted as a switch towards a lake more vulnerable to climate change. |
| Source | Journal of paleolimnology |
| Keywords | Climate warmingEutrophicationInteractive carryoverPaleoecologyResilienceTemporal ecology |
| Journal | Journal of paleolimnology |
| Editor | Kluwer Academic, Boston, Paesi Bassi |
| Year | 2021 |
| Type | Articolo in rivista |
| DOI | 10.1007/s10933-021-00176-y |
| Authors | Bruel, Rosalie; Girardclos, Stéphanie; Marchetto, Aldo; Kremer, Katrina; Crouzet, Christian; Reyss, Jean Louis; Sabatier, Pierre; Perga, Marie Elodie |
| Text | 444224 2021 10.1007/s10933 021 00176 y Scopus 2 s2.0 85099992277 Climate warming Eutrophication Interactive carryover Paleoecology Resilience Temporal ecology Reframing Lake Geneva ecological trajectory in a context of multiple but asynchronous pressures Bruel, Rosalie; Girardclos, Stephanie; Marchetto, Aldo; Kremer, Katrina; Crouzet, Christian; Reyss, Jean Louis; Sabatier, Pierre; Perga, Marie Elodie Institut des Sciences de la Terre, Grenoble; ETH Zurich; Consiglio Nazionale delle Ricerche; Universite Savoie Mont Blanc; University of Vermont; Universite de Geneve; Universite de Lausanne UNIL Regime shifts are major reorganization of ecological processes, creating new sets of mechanisms that drive the new ecological regime. Such rearrangements can affect how and how much the system responds to pressures other than those that created the shift interactive carryover . Lake Geneva still exhibits high levels of productivity despite reductions in phosphorus to its reference baseline; the continued high productivity is likely due to the synergistic effects of climate change. We tested whether the contemporary Lake Geneva plankton community response to air temperature, one symptom of climate change, differed from the responses to past changes in air temperature. We used paleoecology to quantify the changes in plankton communities, as a proxy of general ecological changes, over the past 1500 years. Our results show that from 563 AD beginning of the record to the twentieth century, the cladoceran assemblage remained stable, despite climate variability of 3 °C in air temperature. The plankton community of Lake Geneva appeared to shift for the first time in the 1500 year record in 1946, and dynamic linear models suggested that 1958 1961 was a critical transition period when the ecosystem changed state. Littoral species were lost, and the assemblage became dominated by pelagic species. The shift took place around the beginning of the current long term monitoring program, when local perturbations eutrophication were escalating. Our results suggest that eutrophication acted as a switch towards a lake more vulnerable to climate change. Published version http //www.scopus.com/record/display.url eid=2 s2.0 85099992277 origin=inward Articolo in rivista Kluwer Academic 0921 2728 Journal of paleolimnology Journal of paleolimnology J. paleolimnol. aldo.marchetto MARCHETTO ALDO |
