Effects of water temperature on summer periphyton biomass in shallow lakes: a pan-European mesocosm experiment

Abstract

Periphyton communities play an important role in shallow lakes and are controlled by direct forces such as temperature, light, nutrients, and invertebrate grazing, but also indirectly by planktivorous fish predation. We performed a pan-European lake mesocosm experiment on periphyton colonization covering five countries along a north/south geographical/temperature gradient (Estonia, Germany, Czech Republic, Turkey, and Greece). Periphyton biomass on artificial polypropylene strips exposed at 50 cm water depth at low and high nutrient regimes (with mean total phosphorus concentration of 20 and 65 lg L -1 , respectively) was compared during mid-summer. No significant effect of nutrient loading on periphyton biomass was observed as nutrient concentrations in the mesocosms were generally above limiting values. Water temperature significantly enhanced summer periphyton biomass development. Additionally, direct and indirect top-down control of snails and fish emerged as a significant factor in periphyton biomass control.

Fish but Not Macroinvertebrates Promote Trophic Cascading Effects in High Density Submersed Plant Experimental Lake Food Webs in Two Contrasting Climate Regions

“…The absence of (negative) effects may reflect an oversimplification of our predator assemblages, particularly with a lower richness of fish under our experimental than under natural conditions, leading to greater availability of alternative, more nutritious food sources, such as zooplankton and macroinvertebrates. Moreover, the low mean densities of plant-associated macroinvertebrates in our study might be an effect of the short colonization phase and low accessibility to the mesocosms, notably of snails, which may have prevented indirect positive effects of fish on periphyton, as previously reported for temperate systems [17,85,87,88]. Besides, the extremely high PVI used (ca.…”

Warming Effects on Periphyton Community and Abundance in Different Seasons Are Influenced by Nutrient State and Plant Type: A Shallow Lake Mesocosm Study

“…Climate warming is expected to affect the production and composition of both periphytic and planktonic algae through its direct effect on the physical properties of the water column (Smol et al, 2005;Jeppesen et al, 2009Jeppesen et al, , 2011Rühland et al, 2015) and indirectly by their effect on light availability and nutrient levels in lakes (Salmaso, 2005;Winder and Hunter, 2008;Rühland et al, 2015). How periphyton is affected by global warming is, however, debated (Mahdy et al, 2015). Some studies have shown that warming coupled with nutrient addition alters the temperature effects on periphyton, suggesting complex interactive effects of nutrient and temperature (Trochine et al, 2014;Piggott et al, 2015).…”

Chlorophyll-A Prediction of Lakes with Different Water Quality Patterns in China Based on Hybrid Neural Networks

“…The light conditions in lakes influence the growth of the plankton community, and the eutrophication caused by the high concentration of chlorophyll-a would impact light availability in lakes [6,7]. Excessive nitrogen and phosphorus inputs are important factors to shift lakes from oligotrophic to hypertrophic conditions [8], and lead to dramatic increases in harmful cyanobacteria blooms, which would create a serious threat to lake ecosystems [9].…”