Effects of warming and nutrients on the microbial food web in shallow lake mesocosms

Zingel, Priit
Cremona, Fabien
Noges, Tiina
Cao, Yu
Neif, Erika M.
Coppens, Jan
Iskin, Ugur
Lauridsen, Torben L.
Davidson, Thomas A.
Sondergaard, Martin
Beklioğlu, Meryem
Jeppesen, Erik
We analysed changes in the abundance, biomass and cell size of the microbial food web community (bacteria, heterotrophic nanoflagellates, ciliates) at contrasting nutrient concentrations and temperatures during a simulated heat wave. We used 24 mesocosms mimicking shallow lakes in which two nutrient levels (unenriched and enriched by adding nitrogen and phosphorus) and three different temperature scenarios (ambient, IPCC A2 scenario and A2+%50) are simulated (4 replicates of each). Experiments using the mesocosms have been running un-interrupted since 2003. A 1-month heat wave was imitated by an extra 5 degrees C increase in the previously heated mesocosms (from 1st July to 1st August 2014). Changes in water temperature induced within a few days a strong effect on the microbial food web functioning, demonstrating a quick response of microbial communities to the changes in environment, due to their short generation times. Warming and nutrients showed synergistic effects. Microbial assemblages of heterotrophic nanoflagellates and ciliates responded positively to the heating, the increase being largest in the enriched mesocosms. The results indicate that warming and nutrients in combination can set off complex interactions in the microbial food web functioning. (C) 2018 Elsevier GmbH. All rights reserved.


High hydrostatic pressure induced inactivation kinetics of e. coli o157:h7 and s. aureus in carrot juice and analysis of cell volume change
Pilavtepe, Mutlu; Alpas, Hami; Department of Food Engineering (2007)
The main objective of this study was to determine the pressure induced inactivation mechanism of pressure-resistant Escherichia coli O157:H7 933 and Staphylococcus aureus 485 in a low acid food. Firstly, inactivation curves of pathogens were obtained at 200 to 400 MPa at 40ºC in peptone water and carrot juice. First-order and Weibull models were fitted and Weibull model described the inactivation curves of both pathogens more accurately than first-order model, revealing that food systems could exhibit eithe...
Effect of controlled athmosphere storage,modified athmosphere packaging and gaseous ozone treatment on the survival characteristics of Salmonella enteritidis ay cherry tomatoes
Daş, Elif; Gürakan, Candan; Department of Food Engineering (2004)
In recent years, outbreaks of infections associated with raw and minimally processed fruits and vegetables have been reported. Possible sources for contamination are irrigation water, manure, wash water, handling by workers and contact with contaminated surfaces. Pathogens can occur on raw and minimally processed produce at populations ranging from 103 to 109 CFU/g and able to survive and sometimes grow under various storage conditions. The objective of this study was to analyse the growth/survival of Salmo...
Role of nitrogen in submerged plant development in Mediterranean climatic zone - a mesocosm experiment
Özkan, Korhan; Beklioğlu, Meryem; Department of Biology (2008)
The effects of increasing nitrogen and phosphorus loading on submerged macrophyte development was tested in a mesocosm experiment for three months. Experiment consisted of three NO3-N loadings with factorial of two PO4-P loadings in a fourfold replicated design. Twenty four enclosures placed at one meter depth were isolated from the lake but kept open to sediment and atmosphere. Each enclosure stocked with ten Myriophyllum spicatum shoots with underyearling fish to reduce zooplankton grazers. Biweekly sampl...
OZILGEN, M; CELIK, M; BOZOGLU, F (Elsevier BV, 1991-03-01)
Substrate consumption, ethanol production, microbial growth, and temperature increase in a fermentation vessel are metabolically interrelated biological phenomena. In spontaneous wine fermentations, mixed cultures of various microbial species are involved in the fermentation process. Due to the continuously changing species contributing to the microbial population, these metabolically interrelated parameters are treated separately in the enology literature. In the present study, mathematical models are pres...
Cloning of chitinase a gene (chiA) from serratia marcescens Bn10 and its expression in coleoptera-specific bacillus thuringiensis
Okay, Sezer; Özcengiz, Gülay; Department of Biology (2005)
Chitinases have been shown to be potential agents for biological control of the plant diseases caused by various phytopathogenic fungi and insect pests, because fungal cell walls and insect exoskeletons contain chitin as a major structural component. Chitinase has also been found to increase the efficacy and potency of Bacillus thuringiensis crystal (Cry) proteins toxic to larvae of insect pests. The reason of this synergy is the presence of chitin in the structure of the outer membrane of larval midgut. In...
Citation Formats
P. Zingel et al., “Effects of warming and nutrients on the microbial food web in shallow lake mesocosms,” EUROPEAN JOURNAL OF PROTISTOLOGY, pp. 1–12, 2018, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/43556.