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Aberle, N.

Publications and source records attributed to Aberle, N..

2 recordsLinked to original sources

Exploring Warming Effects on lower food-web dynamics in the plankton of the River Elbe Estuarine Ecosystem in summer: Insights from a Mesocosm Experiment

Understanding how warming alters estuarine plankton communities is essential for predicting future changes in biodiversity and ecosystem functioning. We conducted a four-week indoor mesocosm experiment using natural summer plankton from the Elbe River to examine the effects of warming (+2 {degrees}C and +4 {degrees}C) on abiotic conditions and responses of the plankton community. In this study, oxygen concentrations, primary producer biomass (chlorophyll a, microphytoplankton) and microzooplankton abundances declined sharply during the first 10 days across all treatments while mesozooplankton abundances increased. This suggests a strong top-down control by mesozooplankton on lower trophic levels across all temperature treatments. Primary producers biomass and oxygen concentrations recovered after an initial decline, however to lower levels compared to the onset of the experiment while micro- and mesozooplankton remained low during the second half of the experiment. Nutrient dynamics indicated progressive remineralization, with increasing ammonium, NOx, and silicate concentrations, while phosphate concentrations remained low throughout the experiment. Complementary DNA and RNA metabarcoding revealed similar community turnover over time in all treatments and temperature effects became only pronounced at the end of the experiment. Overall, warming effects were subtle relative to the strong internal trophic dynamics likely caused by the artificial mesocosm setup. Our findings of changes in plankton community dynamics indicate that biotic interactions, changes in trophic diversity and other environmental factors, i.e. oxygen concentrations are likely the drivers of this estuarine system rather than warming alone.

ecology↗

Coupling hydrodynamic drifting simulations and seasonal demographics to forecast the occurrence of jellyfish blooms

O_LIAlthough jellyfish are an important component of coastal marine communities, their public perception is often tainted by their proclivity for aggregating in vast numbers, known as jellyfish blooms. Jellyfish blooms occur worldwide and are associated with major economic ramifications, particularly throughout the fisheries, aquaculture, and tourism sectors. C_LIO_LIForecasting jellyfish blooms is critical in order to manage and mitigate their ecological and economic impacts, but the complex life cycles and cryptic life stages exhibited by most jellyfish species largely precludes accurate predictions of their temporal and spatial occurrence. C_LIO_LIHere we introduce a predictive framework, combining state-of-the-art hydrodynamic simulations and periodic population modelling approaches, to forecast spatial and temporal patterns in the formation of jellyfish blooms. While this framework is sufficiently flexible for accommodating various bloom-forming jellyfish species and impacted coastal regions worldwide, we focus on moon jellyfish (Aurelia aurita) populations within the Baltic Sea as an illustrative example. C_LIO_LIWe emphasise how, through the iterative process of forecasting and model validation, this framework can provide valuable insights for resolving key gaps in our understanding of the drivers of bloom events. Indeed, our framework offers an approach for identifying the, to date, unknown locations of polyp-beds; a crucial parameter in enhancing our capacity to accurately predict the occurrence of jellyfish blooms. Accordingly, our framework, represents a key decision-support tool for mitigating the socioeconomic impacts of bloom formation. C_LI

ecology↗