TY - JOUR A1 - Massie, Thomas Michael A1 - Weithoff, Guntram A1 - Kucklaender, Nina A1 - Gaedke, Ursula A1 - Blasius, Bernd T1 - Enhanced Moran effect by spatial variation in environmental autocorrelation JF - Nature Communications N2 - Spatial correlations in environmental stochasticity can synchronize populations over wide areas, a phenomenon known as the Moran effect. The Moran effect has been confirmed in field, laboratory and theoretical investigations. Little is known, however, about the Moran effect in a common ecological case, when environmental variation is temporally autocorrelated and this autocorrelation varies spatially. Here we perform chemostat experiments to investigate the temporal response of independent phytoplankton populations to autocorrelated stochastic forcing. In contrast to naive expectation, two populations without direct coupling can be more strongly correlated than their environmental forcing (enhanced Moran effect), if the stochastic variations differ in their autocorrelation. Our experimental findings are in agreement with numerical simulations and analytical calculations. The enhanced Moran effect is robust to changes in population dynamics, noise spectra and different measures of correlation-suggesting that noise-induced synchrony may play a larger role for population dynamics than previously thought. Y1 - 2015 U6 - https://doi.org/10.1038/ncomms6993 SN - 2041-1723 VL - 6 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Seebens, Hanno A1 - Essl, Franz A1 - Dawson, Wayne A1 - Fuentes, Nicol A1 - Moser, Dietmar A1 - Pergl, Jan A1 - Pysek, Petr A1 - van Kleunen, Mark A1 - Weber, Ewald A1 - Winter, Marten A1 - Blasius, Bernd T1 - Global trade will accelerate plant invasions in emerging economies under climate change JF - Global change biology N2 - Trade plays a key role in the spread of alien species and has arguably contributed to the recent enormous acceleration of biological invasions, thus homogenizing biotas worldwide. Combining data on 60-year trends of bilateral trade, as well as on biodiversity and climate, we modeled the global spread of plant species among 147 countries. The model results were compared with a recently compiled unique global data set on numbers of naturalized alien vascular plant species representing the most comprehensive collection of naturalized plant distributions currently available. The model identifies major source regions, introduction routes, and hot spots of plant invasions that agree well with observed naturalized plant numbers. In contrast to common knowledge, we show that the 'imperialist dogma,' stating that Europe has been a net exporter of naturalized plants since colonial times, does not hold for the past 60 years, when more naturalized plants were being imported to than exported from Europe. Our results highlight that the current distribution of naturalized plants is best predicted by socioeconomic activities 20 years ago. We took advantage of the observed time lag and used trade developments until recent times to predict naturalized plant trajectories for the next two decades. This shows that particularly strong increases in naturalized plant numbers are expected in the next 20 years for emerging economies in megadiverse regions. The interaction with predicted future climate change will increase invasions in northern temperate countries and reduce them in tropical and (sub) tropical regions, yet not by enough to cancel out the trade-related increase. KW - alien vascular plants KW - bioinvasion KW - climate warming KW - global spread KW - imperialist dogma KW - model KW - network of plant invasion Y1 - 2015 U6 - https://doi.org/10.1111/gcb.13021 SN - 1354-1013 SN - 1365-2486 VL - 21 IS - 11 SP - 4128 EP - 4140 PB - Wiley-Blackwell CY - Hoboken ER -