Impact of Nutrients, Temperatures, and a Heat Wave on Zooplankton Community Structure: An Experimental Approach

Iskin, Ugur
Filiz, Nur
Cao, Yu
Neif, Erika M.
Oglu, Burak
Lauridsen, Torben L.
Davidson, Thomas A.
Sondergaard, Martin
Tavsanoglu, Ulku Nihan
Beklioğlu, Meryem
Jeppesen, Erik
Shallow lakes are globally the most numerous water bodies and are sensitive to external perturbations, including eutrophication and climate change, which threaten their functioning. Extreme events, such as heat waves (HWs), are expected to become more frequent with global warming. To elucidate the effects of nutrients, warming, and HWs on zooplankton community structure, we conducted an experiment in 24 flow-through mesocosms (1.9 m in diameter, 1.0 m deep) imitating shallow lakes. The mesocosms have two nutrient levels (high (HN) and low (LN)) crossed with three temperature scenarios based on the Intergovernmental Panel on Climate Change (IPCC) projections of likely warming scenarios (unheated, A2, and A2 + 50%). The mesocosms had been running continuously with these treatments for 11 years prior to the HW simulation, which consisted of an additional 5 degrees C increase in temperature applied from 1 July to 1 August 2014. The results showed that nutrient effects on the zooplankton community composition and abundance were greater than temperature effects for the period before, during, and after the HW. Before the HW, taxon richness was higher, and functional group diversity and evenness were lower in HN than in LN. We also found a lower biomass of large Cladocera and a lower zooplankton: phytoplankton ratio, indicating higher fish predation in HN than in LN. Concerning the temperature treatment, we found some indication of higher fish predation with warming in LN, but no clear effects in HN. There was a positive nutrient and warming interaction for the biomass of total zooplankton, large and small Copepoda, and the zooplankton: phytoplankton ratio during the HW, which was attributed to recorded HW-induced fish kill. The pattern after the HW largely followed the HW response. Our results suggest a strong nutrient effect on zooplankton, while the effect of temperature treatment and the 5 degrees C HW was comparatively modest, and the changes likely largely reflected changes in predation.


Phytoplankton Community Response to Nutrients, Temperatures, and a Heat Wave in Shallow Lakes: An Experimental Approach
Filiz, Nur; Iskin, Ugur; Beklioğlu, Meryem; Oglu, Burak; Cao, Yu; Davidson, Thomas A.; Sondergaard, Martin; Lauridsen, Torben L.; Jeppesen, Erik (MDPI AG, 2020-12-01)
Phytoplankton usually responds directly and fast to environmental fluctuations, making them useful indicators of lake ecosystem changes caused by various stressors. Here, we examined the phytoplankton community composition before, during, and after a simulated 1-month heat wave in a mesocosm facility in Silkeborg, Denmark. The experiment was conducted over three contrasting temperature scenarios (ambient (A0), Intergovernmental Panel on Climate Change A2 scenario (circa +3 degrees C, A2) and A2+ %50 (circa ...
Influence of Farming Intensity and Climate on Lowland Stream Nitrogen
Goyenola, Guillermo; Graeber, Daniel; Meerhof, Mariana; Jeppesen, Erik; Teixeira-de Mello, Franco; Vidal, Nicolás; Fosalba, Claudia; Ovesen, Niels Bering; Gelbrecht, Joerg; Mazzeo, Néstor; Kronvang, Brian (MDPI AG, 2020-4-2)
Nitrogen lost from agriculture has altered the geochemistry of the biosphere, with pronounced impacts on aquatic ecosystems. We aim to elucidate the patterns and driving factors behind the N fluxes in lowland stream ecosystems differing about land-use and climatic-hydrological conditions. The climate-hydrology areas represented humid cold temperate/stable discharge conditions, and humid subtropical climate/flashy conditions. Three complementary monitoring sampling characteristics were selected, including a ...
Toward predicting climate change effects on lakes: a comparison of 1656 shallow lakes from Florida and Denmark reveals substantial differences in nutrient dynamics, metabolism, trophic structure, and top-down control
Jeppesen, Erik; Canfield, Daniel E.; Bachmann, Roger W.; Sondergaard, Martin; Havens, Karl E.; Johansson, Liselotte S.; Lauridsen, Torben L.; Tserenpil, Sh; Rutter, Robert P.; Warren, Gary; Ji, Gaohua; Hoyer, Mark (Informa UK Limited, 2020-04-01)
Rapid climate changes may potentially have strong impacts on the ecosystem structure and nutrient dynamics of lakes as well as implications for water quality. We used a space-for-time approach to elucidate such possible effects by comparing data from 1656 shallow lakes (mean depth 100 mu g L-1) in the FL lakes, but coverage was higher in the DK lakes at low TP. We also found lower oxygen saturation in the nutrient-rich FL lakes than in the DK lakes, suggesting lower net ecosystem production in the FL lakes....
Climate change impacts on lakes: an integrated ecological perspective based on a multi-faceted approach, with special focus on shallow lakes
Jeppesen, Erik; Meerhoff, Mariana; Davidson, Thomas A.; Trolle, Dennis; Sondergaard, Martin; Lauridsen, Torben L.; Beklioğlu, Meryem; Brucet, Sandra; Volta, Pietro; Gonzalez-Bergonzoni, Ivan; Nielsen, Anders (PAGEPress Publications, 2014-01-01)
Freshwater ecosystems and their biodiversity are presently seriously threatened by global development and population growth, leading to increases in nutrient inputs and intensification of eutrophication-induced problems in receiving fresh waters, particularly in lakes. Climate change constitutes another threat exacerbating the symptoms of eutrophication and species migration and loss. Unequivocal evidence of climate change impacts is still highly fragmented despite the intensive research, in part due to the...
Effects of Crucian Carp (Carassius auratus) on Water Quality in Aquatic Ecosystems: An Experimental Mesocosm Study
Huang, Yehui; Mei, Xueying; Rudstam, Lars G.; Taylor, William D.; Urabe, Jotaro; Jeppesen, Erik; Liu, Zhengwen; Zhang, Xiufeng (MDPI AG, 2020-5-19)
The presence of omnivorous fish is known to affect aquatic ecosystems, including water quality. The effect, however, depends on the species in question, and our knowledge is limited on the effect of omnivorous crucian carp (Carassius auratus), a common and often the most numerous fish species in eutrophic shallow lakes in China. We conducted a 70-day outdoor experiment in mesocosms with and without crucian carp to examine whether this species adversely affects water quality by increasing the levels of total...
Citation Formats
U. Iskin et al., “Impact of Nutrients, Temperatures, and a Heat Wave on Zooplankton Community Structure: An Experimental Approach,” WATER, pp. 0–0, 2020, Accessed: 00, 2021. [Online]. Available: