Patterns of microbial food webs in Mediterranean shallow lakes with contrasting nutrient levels and predation pressures

2018-01-01
ÖZEN, ARDA
Tavsanoglu, Ulku Nihan
Cakiroglu, Ayse Idil
Levi, Eti Ester
Jeppesen, Erik
Beklioğlu, Meryem
To elucidate the specific and combined effects of bottom-up and top-down control on the microbial community in warm lakes, we sampled microbial community along with physical-chemical and biological variables and performed in situ food web experiments, in 14 Turkish shallow lakes with contrasting nutrient levels and predation pressures. Our field results revealed that differences in microbial communities correlated with differences in zooplankton community structure, temperature (increasing nutrient concentrations, change in zooplankton composition), nutrient concentrations (increasing bacteria and heterotrophic nanoflagellate abundances with increasing nitrogen concentrations and temperature) and macrophyte coverage (ciliates as potential consumers of bacteria and HNF was strongest in macrophyte-dominated lakes). Our in situ experimental study revealed that the zooplankton not only affect the biomass and composition of microbial communities but also alter the microbial structure and trophic relationships. Our results therefore indicate that both bottom-up factors and top-down effects were important for the efficiency of the carbon transfer from bacteria to higher trophic levels in the study lakes. Due to an anticipated increase in eutrophication, temperature and alteration of the classical food web with climate warming, major changes in the microbial community of lakes are, therefore, expected in a warmer future in semi-arid Mediterranean climatic regions.
HYDROBIOLOGIA

Suggestions

Patterns of Seasonal Stability of Lake Phytoplankton Mediated by Resource and Grazer Control During Two Decades of Re-oligotrophication
Fu, Hui; Yuan, Guixiang; Özkan, Korhan; Johansson, Liselotter Sander; Sondergaard, Martin; Lauridsen, Torben L.; Jeppesen, Erik (Springer Science and Business Media LLC, 2020-09-01)
Human-induced changes in external nutrient loading affect the phytoplankton community and abundance directly by changing the amount of nutrients available, but also indirectly through changes in the zooplankton (that is, grazer) community structure, mediated in part by changes in the fish community structure and biomass. Such shifts affect the species dynamics and community succession of lake phytoplankton communities, and they may ultimately influence community stability. However, the relative importance o...
Changes of Eutrofication Indicator Parameters (TP, DIN, Chl-a and TRIX) in the Cilician Basin (Northeast Mediterranean)
TUĞRUL, SÜLEYMAN; Uysal, Zahit; Erdogan, Emine; Yucel, Nebil (2011-01-01)
Eutrophication processes and changes in coastal ecosystem are determined by the coastal/open sea interactions and rates of nutrient pollution. The Cilician Basin shelf waters are affected not only by intense industrial activities and increased population, but also by complex atmosphere-sea-land interactions. There is a recognizable difference between water qualities of Mersin bay coastal and the Cilician open waters depleted in nutrients. Eutrophic conditions have developed in the eastern bay shallow waters...
Quantification of the Synergistic Effects of Eutrophication, Apex Predator Pressure, and Internal Processes on the Black Sea Ecosystem
Salihoğlu, Barış (2013-12-01)
In the present study, a model of the lower-trophic pelagic food web of the Black Sea is considered in order to provide a quantitative understanding of the marked changes in the food web structure in response to changing top-down and bottom-up control mechanisms due to eutrophication, overfishing, and climatic changes. The simulations consider three particular parameters controlling the changes in the ecosystem structure due to these stressors; (i) the magnitude of the nitrate flux into the euphotic layer fr...
Monthly changes in primary and bacterial productivity in the North – Eastern Mediterranean shelf waters
Yücel, Nebil; Uysal, Zahit; Department of Marine Biology and Fisheries (2013)
Within the context of this thesis, it was aimed to compare monthly changes in primary and bacterial production rates of eutrophic shelf waters with those of nutrient impoverished oligotrophic open waters taking into consideration of ambient physicochemical properties of the basin waters. In addition, size fractionated primary production and limiting nutrient experiments were also carried out. To achieve these goals, a total of 25 cruises were realized on board R/V Bilim-2 of IMS-METU to collect biological (...
The impact of methionine, tryptophan and proline on methane (95%)-propane (5%) hydrate formation
Longinos, Sotirios Nik; Longinou, Dimitra-Dionisia; Parlaktuna, Mahmut; Toktarbay, Zhexenbek (2021-10-01)
This study examines the impact of three amino acids such as proline, methionine and tryptophan on methane (95%)-propane (5%) hydrate formation with the use of different impellers. The concentration of amino acids was 1 wt% at 24.5 bar and 2 degrees C. Based on experimental outcomes proline behaves as inhibitor and methionine and tryptophan perform as promoters. RT experiments both formed more quickly gas hydrates and indicated higher values in rate of hydrate formation compared to PBTU and PBTD experiments ...
Citation Formats
A. ÖZEN, U. N. Tavsanoglu, A. I. Cakiroglu, E. E. Levi, E. Jeppesen, and M. Beklioğlu, “Patterns of microbial food webs in Mediterranean shallow lakes with contrasting nutrient levels and predation pressures,” HYDROBIOLOGIA, pp. 13–27, 2018, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/43670.