Contrasting response of two shallow eutrophic cold temperate lakes to a partial winterkill of fish

Hilt, Sabine; Wanke, Thomas; Scharnweber, Kristin; Brauns, Mario; Syväranta, Jari; Gaedke, Ursula; Köhler, Jan; Lischke, Betty; Mehner, Thomas

doi:10.1007/s10750-014-2143-7

Cited by 12 publications

(16 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

Section: Discussionmentioning

confidence: 95%

“…Previous detailed analyses of the feeding interactions in the pelagic habitat of both lakes have shown that crustacean biomasses were reduced and ciliate biomasses increased as a consequence of a partial winter fish kill (Hilt et al 2015, Lischke et al 2016. The resulting strong predation pressure by ciliates likely reduced the biomass of small phytoplankton and pelagic bacteria and benefitted large phytoplankton species (Lischke et al 2016).…”

Section: Community-wide Size Spectramentioning

confidence: 95%

See 1 more Smart Citation

Empirical correspondence between trophic transfer efficiency in freshwater food webs and the slope of their size spectra

Mehner

Lischke

Scharnweber

et al. 2018

Ecology

Self Cite

View full text Add to dashboard Cite

The density of organisms declines with size, because larger organisms need more energy than smaller ones and energetic losses occur when larger organisms feed on smaller ones. A potential expression of density-size distributions are Normalized Biomass Size Spectra (NBSS), which plot the logarithm of biomass independent of taxonomy within bins of logarithmic organismal size, divided by the bin width. Theoretically, the NBSS slope of multi-trophic communities is exactly -1.0 if the trophic transfer efficiency (TTE, ratio of production rates between adjacent trophic levels) is 10% and the predator-prey mass ratio (PPMR) is fixed at 10 . Here we provide evidence from four multi-trophic lake food webs that empirically estimated TTEs correspond to empirically estimated slopes of the respective community NBSS. Each of the NBSS considered pelagic and benthic organisms spanning size ranges from bacteria to fish, all sampled over three seasons in 1 yr. The four NBSS slopes were significantly steeper than -1.0 (range -1.14 to -1.19, with 95% CIs excluding -1). The corresponding average TTEs were substantially lower than 10% in each of the four food webs (range 1.0% to 3.6%, mean 1.85%). The overall slope merging all biomass-size data pairs from the four systems (-1.17) was almost identical to the slope predicted from the arithmetic mean TTE of the four food webs (-1.18) assuming a constant PPMR of 10 . Accordingly, our empirical data confirm the theoretically predicted quantitative relationship between TTE and the slope of the biomass-size distribution. Furthermore, we show that benthic and pelagic organisms can be merged into a community NBSS, but future studies have yet to explore potential differences in habitat-specific TTEs and PPMRs. We suggest that community NBSS may provide valuable information on the structure of food webs and their energetic pathways, and can result in improved accuracy of TTE-estimates.

show abstract

Section: Discussionmentioning

confidence: 95%

Section: Community-wide Size Spectramentioning

confidence: 95%

Empirical correspondence between trophic transfer efficiency in freshwater food webs and the slope of their size spectra

Mehner

Lischke

Scharnweber

et al. 2018

Ecology

Self Cite

View full text Add to dashboard Cite

show abstract

“…Omnivorous fish species in both lakes relied more on benthic than on pelagic production , but due to overall low fish biomasses (Hilt et al, 2015), their topdown control on macrozoobenthos was low and thus their feeding would not explain the low benthic efficiencies. Pelagic and benthic habitats may be energetically linked, and this may bias the habitat-specific efficiencies.…”

Section: Discussionmentioning

confidence: 96%

“…The food-web structure was derived using information gained in previous studies on the community composition of zooplankton (Lischke et al, 2016), macrozoobenthos (K. Scharnweber, unpublished data), and stable isotope analyses of crustacean zooplankton, macrozoobenthos and fish . The low crustacean biomass was dominated by nauplii and copepodites as a consequence of a severe predation pressure by YOY fish (Hilt et al, 2015;Lischke et al, 2016). Phytoplankton and pelagic bacteria were considered to be the pelagic basal producers, and macrophytes, epiphytes, epipelon and sediment bacteria the benthic basal producers.…”

Section: Food Webmentioning

confidence: 99%

“…These were estimated from a standardised fishing campaign using four Nordic multimesh gillnets which were installed perpendicular to the shoreline from dusk until dawn, and additional standardised electrofishing (applying 15 dips for 15 s at randomly chosen locations) (see Brothers, Hilt, Attermeyer, et al, 2013;Mehner et al, 2016 for details). Young of the year (YOY) fish were likely abundant (Hilt et al, 2015), however, we were not able to quantify their biomass and production.…”

Section: Fishmentioning

confidence: 99%

See 1 more Smart Citation

Benthic carbon is inefficiently transferred in the food webs of two eutrophic shallow lakes

et al. 2017

Self Cite

View full text Add to dashboard Cite

The sum of benthic autotrophic and bacterial production often exceeds the sum of pelagic autotrophic and bacterial production, and hence may contribute substantially to whole‐lake carbon fluxes, especially in shallow lakes. Furthermore, both benthic and pelagic autotrophic and bacterial production are highly edible and of sufficient nutritional quality for animal consumers. We thus hypothesised that pelagic and benthic transfer efficiencies (ratios of production at adjacent trophic levels) in shallow lakes should be similar. We performed whole ecosystem studies in two shallow lakes (3.5 ha, mean depth 2 m), one with and one without submerged macrophytes, and quantified pelagic and benthic biomass, production and transfer efficiencies for bacteria, phytoplankton, epipelon, epiphyton, macrophytes, zooplankton, macrozoobenthos and fish. We expected higher transfer efficiencies in the lake with macrophytes, because these provide shelter and food for macrozoobenthos and may thus enable a more efficient conversion of basal production to consumer production. In both lakes, the majority of the whole‐lake autotrophic and bacterial production was provided by benthic organisms, but whole‐lake primary consumer production mostly relied on pelagic autotrophic and bacterial production. Consequently, transfer efficiency of benthic autotrophic and bacterial production to macrozoobenthos production was an order of magnitude lower than the transfer efficiency of pelagic autotrophic and bacterial production to rotifer and crustacean production. Between‐lake differences in transfer efficiencies were minor. We discuss several aspects potentially causing the unexpectedly low benthic transfer efficiencies, such as the food quality of producers, pelagic–benthic links, oxygen concentrations in the deeper lake areas and additional unaccounted consumer production by pelagic and benthic protozoa and meiobenthos at intermediate or top trophic levels. None of these processes convincingly explain the large differences between benthic and pelagic transfer efficiencies. Our data indicate that shallow eutrophic lakes, even with a major share of autotrophic and bacterial production in the benthic zone, can function as pelagic systems with respect to primary consumer production. We suggest that the benthic autotrophic production was mostly transferred to benthic bacterial production, which remained in the sediments, potentially cycling internally in a similar way to what has previously been described for the microbial loop in pelagic habitats. Understanding the energetics of whole‐lake food webs, including the fate of the substantial benthic bacterial production, which is either mineralised at the sediment surface or permanently buried, has important implications for regional and global carbon cycling.

show abstract

Weak Response of Animal Allochthony and Production to Enhanced Supply of Terrestrial Leaf Litter in Nutrient-Rich Lakes

Mehner

Attermeyer

Brauns³

et al. 2015

Ecosystems

View full text Add to dashboard Cite

Contrasting response of two shallow eutrophic cold temperate lakes to a partial winterkill of fish

Cited by 12 publications

References 48 publications

Empirical correspondence between trophic transfer efficiency in freshwater food webs and the slope of their size spectra

Empirical correspondence between trophic transfer efficiency in freshwater food webs and the slope of their size spectra

Benthic carbon is inefficiently transferred in the food webs of two eutrophic shallow lakes

Weak Response of Animal Allochthony and Production to Enhanced Supply of Terrestrial Leaf Litter in Nutrient-Rich Lakes

Contact Info

Product

Resources

About