Food-web manipulation in shallow, eutrophic lakes: bridging the gap between the whole-lake approach and behavioural and demographic studies

Relative impacts of bottom-up (producer controlled) and top-down (consumer controlled) forces on the biomass and size structure of five major components of freshwater pelagic systems (piscivores, planktivores, zooplankton, phytoplankton, and total phosphorus availability) were estimated. Predictions that emerge are (1) maximum biomass at each trophic level is controlled from below (bottom-up) by nutrient availability, (2) this bottom-up regulation is strongest at the bottom of the food web (i.e. phosphorus → phytoplankton) and weakens by a factor of 2 with each succeeding step up the food web, (3) as energy moves up a food web, the predictability of bottom-up interactions decreases, (4) near the top of the food web, top-down (predator mediated) interactions are strong and have low coefficients of variation, but weaken with every step down the food web, (5) variability around the bottom-up regressions can always be explained by top-down forces, and (6) interplay between top-down and bottom-up effects changes with the trophic status of lakes. In eutrophic lakes, top-down effects are strong for piscivore → zooplankton, weaker for planktivore → zooplankton, and have little impact for zooplankton → phytoplankton. For oligotrophic lakes, the model predicts that top-down effects are not strongly buffered, so that zooplankton → phytoplankton interactions are significant.

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Effect of water chemistry on zooplanktonic and microbial communities across freshwater ecotones in different macrophyte-dominated shallow lakes

Journal of Limnology ◽

10.4081/jlimnol.2015.1338 ◽

2015 ◽

Cited By ~ 4

Author(s):

Tomasz Mieczan ◽

Małgorzata Adamczuk ◽

Monika Tarkowska-Kukuryk ◽

Dorota Nawrot

Keyword(s):

Food Web ◽

Contact Zone ◽

Shallow Lakes ◽

Environmental Variables ◽

Open Water ◽

Total Variance ◽

Pelagic Zone ◽

Minor Role ◽

Eutrophic Lakes ◽

Planktonic Food

Complex interactions between zooplankton and microbial food webs are vital to the ecosystem ecology of shallow lakes. However, little is known about how horizontal changes in environmental conditions may influence microbial and metazoan communities in shallow lakes. The specific goals of the study were i) to describe environmental variables responsible for the distribution of bacteria, flagellates, ciliates and crustaceans in an adjacent canal, ecotone and reservoir (littoral-pelagic zone) in two different types of lakes (Ceratophyllum-dominated and Potamogeton-dominated lakes); ii) to determine whether the contact zone waters differ in hydrochemical and biological terms from the waters of the canal and the open water zone; iii) and to evaluate the influence of particular macro-habitats (canal, canal/reservoir, littoral and pelagic zone) on the interactions between components of the planktonic food web. We studied four shallow, eutrophic lakes in Polesie Lubelskie (eastern Poland). The highest diversity and abundance of microorganisms and crustaceans were observed in the canal-reservoir contact zone, while the lowest values were noted in the pelagic zone. Hence, the contact zone in the investigated lakes could fulfil the function of an ecotone, distinguished by a significant increase in biodiversity, abundance, and species specificity of micro- and macroorganisms. Weak relations between food web components were found in the Ceratophyllum-dominated lakes, where environmental variables explained the bulk of the total variance in plankton abundance, whereas in the Potamogeton-dominated lakes, where environmental variables had a minor role in the total variance in plankton abundance, strong predator-prey relations were noted. Spatial structure of habitats proved to be another important factor for relationships between food web components, as our study indicated that habitat complexity can reduce negative correlations between food web components. Our study contributes to knowledge of the functioning of eutrophic lakes in the current era of increasing eutrophication caused by climate change and human activity.

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Food-web studies in shallow eutrophic lakes by the Netherlands Institute of Ecology: Main results, knowledge gaps and new perspectives

Netherlands Journal of Aquatic Ecology ◽

10.1007/bf02336927 ◽

1993 ◽

Vol 27 (1) ◽

pp. 35-49 ◽

Cited By ~ 3

Author(s):

J. Vijverberg ◽

R. D. Gulati ◽

W. M. Mooij

Keyword(s):

The Netherlands ◽

Food Web ◽

Knowledge Gaps ◽

Eutrophic Lakes ◽

Web Studies

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Application of subfossil Bosmina and its δ13C values in tracing the long-term food web dynamics of shallow eutrophic lakes: A case in Taihu Lake, southeast China

The Science of The Total Environment ◽

10.1016/j.scitotenv.2020.138909 ◽

2020 ◽

Vol 730 ◽

pp. 138909

Author(s):

Longjuan Cheng ◽

Giri Kattel ◽

Bin Xue ◽

Shuchun Yao ◽

Lingling Li ◽

...

Keyword(s):

Food Web ◽

Taihu Lake ◽

Eutrophic Lakes ◽

Southeast China ◽

Δ13c Values ◽

Food Web Dynamics

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Effects of whole-lake manipulations of nutrient loading and food web structure on planktonic respiration

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f99-279 ◽

2000 ◽

Vol 57 (2) ◽

pp. 487-496 ◽

Cited By ~ 17

Author(s):

Michael L Pace ◽

Jonathan J Cole

Keyword(s):

Organic Carbon ◽

Dissolved Organic Carbon ◽

Food Web ◽

Bacterial Production ◽

Nutrient Loading ◽

Nutrient Loads ◽

Food Web Structure ◽

Eutrophic Lakes ◽

Dark Bottle ◽

Web Structure

We assessed planktonic respiration in whole-lake manipulations of nutrient loading and food web structure in three manipulated and one unmanipulated lake over 7 years. The manipulations created strong contrasts in zooplankton body size across a series of nutrient loads. Large-bodied zooplankton were suppressed by planktivorous fish in one lake, while in the other two manipulated lakes, large-bodied zooplankton dominated community biomass. Nutrients were added as inorganic N and P. Nutrient loads ranged from background to conditions resembling eutrophic lakes. Planktonic respiration was measured weekly in each lake by dark bottle oxygen consumption. Respiration was low when lakes were not fertilized (average 8.5 µmol O2·L-1·day-1) and was correlated with differences in dissolved organic carbon among the lakes. Respiration increased with nutrient addition to a mean range of 12-25 µmol O2·L-1·day-1; however, respiration differed among lakes at the same nutrient loading. Further, respiration was independent of dissolved organic carbon in the fertilized lakes. Differences in the intensity of zooplankton grazing as determined by food web structure strongly regulated primary and bacterial production across the range of nutrient loads. Consequently, respiration was positively related to primary production, phytoplankton biomass, and bacterial production and inversely related to the average size of crustacean zooplankton.

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The effect of epiphytic macroinvertebrates on microbial communities in different types of macrophyte-dominated shallow lakes

Knowledge and Management of Aquatic Ecosystems ◽

10.1051/kmae/2017060 ◽

2018 ◽

pp. 13 ◽

Cited By ~ 1

Author(s):

Tomasz Mieczan ◽

Monika Tarkowska-Kukuryk ◽

Diana Ȃrva ◽

Làszló Berzni-Nagy ◽

Zoltan Novak ◽

...

Keyword(s):

Food Web ◽

Microbial Communities ◽

Shallow Lakes ◽

Environmental Variables ◽

Total Variance ◽

Minor Role ◽

Eutrophic Lakes ◽

Epiphytic Fauna ◽

Different Types ◽

The Impact

Complex interactions between epiphytic fauna and microbial food webs in periphyton are vital to the ecosystem ecology of shallow lakes. However, little is known about how different types of macrophyte dominated lakes may influence microbial and metazoan communities. The goal of the present study was to examine the impact of metazoan on microbial food web in three different types of lakes (Stratiotes-dominated,Ceratophyllum-dominated andPotamogeton-dominated). The results of this study suggest a strong correlations between chironomid larvae, small Metazoa and microbial communities in the periphyton of macrophyte-dominated lakes. Weak relations between food web components were found in thePotamogeton-dominated andCeratophyllum-dominated lakes, where environmental variables explained the bulk of the total variance in periphyton abundance, whereas strong predator-prey relations were noted in theStratiotes-dominated lake, where environmental variables had a minor role in the total variance in periphyton abundance. Our study contributes to knowledge of the functioning of eutrophic lakes in the current era of increasing eutrophication caused by climate change and human activity.

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