Autumnal and Over-Winter Limnology of Three Small Eutrophic Lakes with Particular Reference to Experimental Circulation and Trout Mortality

The autumnal and over-winter limnological characteristics of two small eutrophic lakes differed considerably from those of a third eutrophic lake; all were close to each other in the southwest interior of British Columbia. Thermal and chemical stratification was well defined in Marquette and Corbett lakes because local topography provided protection from wind action; stratification in the more exposed Courtney Lake was ill defined. Average wind velocities during summer and autumn on Courtney Lake were 4.3 times as great as, and more unidirectional than, those on Corbett Lake and probably Marquette. Complete natural autumnal oxygenation and circulation in Courtney Lake provided comparatively high concentrations of dissolved oxygen which permitted the over-winter survival of Salmo gairdneri and Richardsonius balteatus. Although Marquette and Corbett lakes were isothermal in late autumn, oxygen concentrations were well below saturation levels and circulation was probably incomplete. Consequently oxygen depletion during winter was severe and S. gairdneri and Salvelinus fontinalis were subject to over-winter mortality.Experimental circulation of Corbett Lake, just prior to ice cover, confirmed the hypothesis that incomplete autumnal oxygenation is a cause of "winter kill" of fishes. Artificial autumnal circulation of the lake provided an oxygen concentration sufficient to prevent overwinter fish mortality. However, over-winter mortality of the entire fish population did occur in the control lake, Marquette (incomplete autumnal oxygenation) but not in Courtney Lake (complete autumnal oxygenation).

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Phosphorus-binding forms in the sediment of an oligotrophic and an eutrophic hardwater lake of the Baltic Lake District (Germany)

Water Science & Technology ◽

10.2166/wst.1998.0173 ◽

1998 ◽

Vol 37 (3) ◽

pp. 51-58 ◽

Cited By ~ 69

Author(s):

Thomas Gonsiorczyk ◽

Peter Casper ◽

Rainer Koschel

Keyword(s):

Eutrophic Lake ◽

Oligotrophic Lake ◽

Sediment Surface ◽

Eutrophic Lakes ◽

P Release ◽

Binding Forms ◽

Fe And Mn ◽

Lake Stechlin ◽

High Concentrations ◽

The Baltic

The vertical distribution of various phosphorus (P)-binding forms, associated potential P-binding partners and the composition of dry material were investigated in the bottom sediments of the dimictic oligotrophic Lake Stechlin and the dimictic eutrophic Lake Feldberger Haussee. Reductant soluble P (Fe- and Mn-bound) at the sediment surface (0−1 cm) was considerably higher in the oligotrophic Lake Stechlin (1.29 g kg−1) than in the eutrophic Lake Haussee (0.32 g kg−1). The amounts of dissolved, loosely adsorbed, metal oxide- and calcium carbonate bound P were higher in the eutrophic lake. The depth profiles of the investigated P species indicated that the mobilization of Fe- and Mn-bound P is the most important mechanism of P-release in oligotrophic lakes, whereas the mobilization of recently sedimented labile organic bound P seems to be the driving force of P-release in eutrophic lakes. In both lakes autochthonous calcite precipitations occurs during the summer months. The coprecipitation of P with calcite is an important self-cleaning mechanism in eutrophic hardwater lakes and contributes to the permanent burial of P in the sediments. Although, the precipitation of calcite is inhibited by the presence of high concentrations of soluble reactive P, the coprecipitation of P with calcite seems to be enhanced.

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Genetic Diversity of Small Eukaryotes in Lakes Differing by Their Trophic Status

Applied and Environmental Microbiology ◽

10.1128/aem.71.10.5935-5942.2005 ◽

2005 ◽

Vol 71 (10) ◽

pp. 5935-5942 ◽

Cited By ~ 131

Author(s):

Marie Lefranc ◽

Aurélie Thénot ◽

Cécile Lepère ◽

Didier Debroas

Keyword(s):

Trophic Status ◽

Eutrophic Lake ◽

Rrna Genes ◽

Eutrophic Lakes ◽

Massif Central ◽

Operational Taxonomic Units ◽

Single Clone ◽

18S Rrna Genes ◽

Lake Pavin ◽

Environmental Sequences

ABSTRACT Small eukaryotes, cells with a diameter of less than 5 μm, are fundamental components of lacustrine planktonic systems. In this study, small-eukaryote diversity was determined by sequencing cloned 18S rRNA genes in three libraries from lakes of differing trophic status in the Massif Central, France: the oligotrophic Lake Godivelle, the oligomesotrophic Lake Pavin, and the eutrophic Lake Aydat. This analysis shows that the least diversified library was in the eutrophic lake (12 operational taxonomic units [OTUs]) and the most diversified was in the oligomesotrophic lake (26 OTUs). Certain groups were present in at least two ecosystems, while the others were specific to one lake on the sampling date. Cryptophyta, Chrysophyceae, and the strictly heterotrophic eukaryotes, Ciliophora and fungi, were identified in the three libraries. Among the small eukaryotes found only in two lakes, Choanoflagellida and environmental sequences (LKM11) were not detected in the eutrophic system whereas Cercozoa were confined to the oligomesotrophic and eutrophic lakes. Three OTUs, linked to the Perkinsozoa, were detected only in the Aydat library, where they represented 60% of the clones of the library. Chlorophyta and Haptophyta lineages were represented by a single clone and were present only in Godivelle and Pavin, respectively. Of the 127 clones studied, classical pigmented organisms (autotrophs and mixotrophs) represented only a low proportion regardless of the library's origin. This study shows that the small-eukaryote community composition may differ as a function of trophic status; certain lineages could be detected only in a single ecosystem.

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Earth observation for monitoring and mapping of cyanobacteria blooms. Case studies on five Italian lakes

Journal of Limnology ◽

10.4081/jlimnol.2016.1565 ◽

2016 ◽

Vol 76 (s1) ◽

Cited By ~ 13

Author(s):

Mariano Bresciani ◽

Claudia Giardino ◽

Rosaria Lauceri ◽

Erica Matta ◽

Ilaria Cazzaniga ◽

...

Keyword(s):

Remote Sensing ◽

Algal Blooms ◽

Remote Sensing Data ◽

Late Summer ◽

Eutrophic Lake ◽

Cyanobacterial Blooms ◽

Landsat 8 ◽

Negative Effects ◽

Eutrophic Lakes ◽

Chl A

Cyanobacterial blooms occur in many parts of the world as a result of entirely natural causes or human activity. Due to their negative effects on water resources, efforts are made to monitor cyanobacteria dynamics. This study discusses the contribution of remote sensing methods for mapping cyanobacterial blooms in lakes in northern Italy. Semi-empirical approaches were used to flag scum and cyanobacteria and spectral inversion of bio-optical models was adopted to retrieve chlorophyll-a (Chl-a) concentrations. Landsat-8 OLI data provided us both the spatial distribution of Chl-a concentrations in a small eutrophic lake and the patchy distribution of scum in Lake Como. ENVISAT MERIS time series collected from 2003 to 2011 enabled the identification of dates when cyanobacterial blooms affected water quality in three small meso-eutrophic lakes in the same region. On average, algal blooms occurred in the three lakes for about 5 days a year, typically in late summer and early autumn. A suite of hyperspectral sensors on air- and space-borne platforms was used to map Chl-a concentrations in the productive waters of the Mantua lakes, finding values in the range of 20 to 100 mgm-3. The present findings were obtained by applying state of the art of methods applied to remote sensing data. Further research will focus on improving the accuracy of cyanobacteria mapping and adapting the algorithms to the new-generation of satellite sensors.

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Factors Controlling Oxygen Depletion in Ice-Covered Lakes

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f80-024 ◽

1980 ◽

Vol 37 (2) ◽

pp. 185-194 ◽

Cited By ~ 79

Author(s):

Jack A. Mathias ◽

Jan Barica

Keyword(s):

Volume Ratio ◽

Lake Management ◽

Eddy Diffusion ◽

Oxygen Depletion ◽

Eutrophic Lakes ◽

Experimental Lakes Area ◽

Lake Volume ◽

Basin Morphometry ◽

Depletion Rate ◽

Prairie Lakes

Winter oxygen depletion rates from four sets of Canadian lakes (prairie, southeastern Ontario, Arctic, and Experimental Lakes Area) differing in morphometry and trophic state, were analyzed. An inverse relationship was found between oxygen depletion rate and mean depth. The effect of lake trophic status on oxygen depletion rate was demonstrable after the influence of basin morphometry was removed by regression of oxygen depletion rate against the sediment area: lake volume ratio. The sediments of eutrophic lakes consumed oxygen about 3 times faster (0.23 g∙m−2∙d−1) than those of oligotrophic lakes (0.08 g∙m−2∙d−1), but water column respiration was about the same (0.01 g∙m−3∙d−1) for both groups of lakes. Data from prairie lakes showed that the winter oxygen consumption was limited by oxygen supply below an average whole-lake oxygen concentration of 3.8 mg∙L−1. The rate of eddy diffusion near the sediments in ice-covered prairie lakes was 3.72 ± 1.41 × 10−3 cm2∙s−1. Implications for lake management during the winter are discussed.Key words: oxygen, depletion, respiration, lakes, ice-covered, winter, sediments, model, consumption

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Identification of Regime Shifts and Their Potential Drivers in the Shallow Eutrophic Lake Yilong, Southwest China

Sustainability ◽

10.3390/su12093704 ◽

2020 ◽

Vol 12 (9) ◽

pp. 3704

Author(s):

Lei Zhao ◽

Mingguo Wang ◽

Zhongyao Liang ◽

Qichao Zhou

Keyword(s):

Regime Shift ◽

Eutrophic Lake ◽

Regime Shifts ◽

Nutrient Reduction ◽

Eutrophic Lakes ◽

Test Analysis ◽

Key Drivers ◽

High Possibility ◽

Cage Fish

Regime shifts in shallow lakes can lead to great changes in ecosystem structures and functions, making ecosystem management more complicated. Lake Yilong, located in Yunnan Province, is one of the most eutrophic lakes in China. Although there is a high possibility that this lake has undergone regime shift one or more times, the presence of regime shifts and their drivers remain unknown. Here, we employed the sequential t-test analysis of regime shifts to detect the regime shifts based on the long-term (1989–2018) dataset of the lake. We further determined their potential drivers, and explored the nutrient thresholds of regime shifts and hysteresis. The results showed that during the testing period, three regime shifts occurred in 1996 (restorative type), 2009 (catastrophic type) and 2014 (restorative type). The potential key drivers for the first two regime shifts (1996 and 2009) were both related to aquaculture. The abolition of cage fish culture may have led to the restorative regime shift in 1996, and the stocking of crabs and excessive premature releasing of fry possibly caused the catastrophic regime shift in 2009. However, the third regime shift, which occurred in 2014, was possibly related to the drought and succedent hydration. These results indicate that adjustments of aquaculture strategy and hydrological conditions are critical for the lake ecosystem’s recovery. Moreover, the total phosphorus thresholds were identified to be lower than 0.046 mg/L (restorative type) and higher than 0.105 mg/L (catastrophic type), respectively. In addition, an obvious hysteresis was observed after 2014, suggesting that nutrient reduction is important for this lake’s management in the future.

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Effects of eutrophication on sedimentary organic carbon cycling in five temperate lakes

Biogeosciences ◽

10.5194/bg-16-3725-2019 ◽

2019 ◽

Vol 16 (19) ◽

pp. 3725-3746 ◽

Cited By ~ 3

Author(s):

Annika Fiskal ◽

Longhui Deng ◽

Anja Michel ◽

Philip Eickenbusch ◽

Xingguo Han ◽

...

Keyword(s):

Organic Carbon ◽

Water Column ◽

Trophic State ◽

Microbial Respiration ◽

Accumulation Rate ◽

Eutrophic Lake ◽

Accumulation Rates ◽

Artificial Lake ◽

Eutrophic Lakes ◽

Lake Ecosystems

Abstract. Even though human-induced eutrophication has severely impacted temperate lake ecosystems over the last centuries, the effects on total organic carbon (TOC) burial and mineralization are not well understood. We study these effects based on sedimentary records from the last 180 years in five Swiss lakes that differ in trophic state. We compare changes in TOC content and modeled TOC accumulation rates through time to historical data on algae blooms, water column anoxia, wastewater treatment, artificial lake ventilation, and water column phosphorus (P) concentrations. We furthermore investigate the effects of eutrophication on rates of microbial TOC mineralization and vertical distributions of microbial respiration reactions in sediments. Our results indicate that the history of eutrophication is well recorded in the sedimentary record. Overall, eutrophic lakes have higher TOC burial and accumulation rates, and subsurface peaks in TOC coincide with past periods of elevated P concentrations in lake water. Sediments of eutrophic lakes, moreover, have higher rates of total respiration and higher contributions of methanogenesis to total respiration. However, we found strong overlaps in the distributions of respiration reactions involving different electron acceptors in all lakes regardless of lake trophic state. Moreover, even though water column P concentrations have been reduced by ∼ 50 %–90 % since the period of peak eutrophication in the 1970s, TOC burial and accumulation rates have only decreased significantly, by ∼ 20 % and 25 %, in two of the five lakes. Hereby there is no clear relationship between the magnitude of the P concentration decrease and the change in TOC burial and accumulation rate. Instead, data from one eutrophic lake suggest that artificial ventilation, which has been used to prevent water column anoxia in this lake for 35 years, may help sustain high rates of TOC burial and accumulation in sediments despite water column P concentrations being strongly reduced. Our study provides novel insights into the influence of human activities in lakes and lake watersheds on lake sediments as carbon sinks and habitats for diverse microbial respiration processes.

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Evolution of river pollutions under the influence of local hydro-climatic changes - the example of the Bienne River (Jura Mountain, France)

10.5194/egusphere-egu2020-5986 ◽

2020 ◽

Author(s):

Elie Dhivert ◽

François Gibon ◽

Karine Hochart ◽

Bertrand Devillers

Keyword(s):

Climatic Changes ◽

Fish Mortality ◽

Risk Level ◽

Rainfall Regime ◽

Pollution Levels ◽

Resilience Process ◽

Wide Range ◽

River Quality ◽

High Concentrations ◽

The Impact

<p>In application of the EU Water Framework Directive, many actions have been undertaken in order to reduce pollution levels in river systems. However, for certain catchments, the resilience process is not occurring as expected. In the Bienne River basin, metals discharge has plummeted since the 1990s, following the implementation of a better industrial waste management, as well as an important industrial restructuring. Nevertheless, this river has been regularly affected by massive fish mortality over the 2012-2019 period. This phenomenon, never identified before, is becoming recurrent. Organic tissues sampled in dead fish contained high concentrations of metals in association with other toxics. In this context, this study introduces a transdisciplinary approach in order to: (i) analyse spatial and temporal evolutions of pollutions in the Bienne River, (ii) evaluate potential ecotoxicological impacts associated, (iii) identify interactions with local hydro-climatic changes. Metallic and organic pollutants were analysed over different stations and at multi-temporal scales, associating sedimentary archives, suspended matters and passive water samplers. These analyses highlight the impact on the river quality of both current and legacy pollutions, particularly during prolonged low-water periods and high discharge events. Ecotoxicological analyses emphasize a severe risk level in the case of polluted sediments remobilization, especially because of heavy metals and PAH contamination. Geochemical evidence of such remobilization events has been recorded over the last decade in a sedimentary core sampled in the downstream part of the Bienne River. Hydrological data recorded in the Bienne River gauging stations since 1971 attests of an important year-to-year variability, although changes in the river discharge distribution are ongoing. Data has shown a higher frequency of both the lowest and the highest outflows over the 2012-2019 period compared to the rest of the hydrological recording. Hydro-climatic variables coming from in-situ measurements and satellite data (GPM-IMERG6) has also shown significant modifications in the rainfall regime over this period, especially in the augmentation of dry spells and heavy rainfall episodes. Those modifications agree well with the discharge change observations. This study brings out knock-on impacts of combined geochemical, ecotoxicological and hydro-sedimentary issues on the fate of aquatic ecosystems, especially under the influence of local hydro-climatic changes and their implications on hydrological regimes. Those results aim at reducing uncertainties concerning the evolution of the river quality by highlighting such a tipping point for environmental conditions. In addition, such a study helps us to grasp the complexity of local stakes regarding the multiple interests of a wide range of stakeholders and policy makers involved on the field.</p>

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Rapid adaptation of harmful cyanobacteria to rising CO2

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1602435113 ◽

2016 ◽

Vol 113 (33) ◽

pp. 9315-9320 ◽

Cited By ~ 49

Author(s):

Giovanni Sandrini ◽

Xing Ji ◽

Jolanda M. H. Verspagen ◽

Robert P. Tann ◽

Pieter C. Slot ◽

...

Keyword(s):

Cyanobacterial Bloom ◽

Eutrophic Lake ◽

Cyanobacterial Blooms ◽

High Flux ◽

Flux Rate ◽

Eutrophic Lakes ◽

Field Evidence ◽

Evolutionary Changes ◽

Lakes And Reservoirs ◽

Harmful Cyanobacterial Blooms

Rising atmospheric CO2 concentrations are likely to affect many ecosystems worldwide. However, to what extent elevated CO2 will induce evolutionary changes in photosynthetic organisms is still a major open question. Here, we show rapid microevolutionary adaptation of a harmful cyanobacterium to changes in inorganic carbon (Ci) availability. We studied the cyanobacterium Microcystis, a notorious genus that can develop toxic cyanobacterial blooms in many eutrophic lakes and reservoirs worldwide. Microcystis displays genetic variation in the Ci uptake systems BicA and SbtA, where BicA has a low affinity for bicarbonate but high flux rate, and SbtA has a high affinity but low flux rate. Our laboratory competition experiments show that bicA + sbtA genotypes were favored by natural selection at low CO2 levels, but were partially replaced by the bicA genotype at elevated CO2. Similarly, in a eutrophic lake, bicA + sbtA strains were dominant when Ci concentrations were depleted during a dense cyanobacterial bloom, but were replaced by strains with only the high-flux bicA gene when Ci concentrations increased later in the season. Hence, our results provide both laboratory and field evidence that increasing carbon concentrations induce rapid adaptive changes in the genotype composition of harmful cyanobacterial blooms.

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Transport and Burial as a Cause of Whitefish (Coregonus sp.) Egg Mortality in a Eutrophic Lake

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f94-192 ◽

1994 ◽

Vol 51 (9) ◽

pp. 1908-1919 ◽

Cited By ~ 19

Author(s):

Andrea R. Ventling-Schwank ◽

David M. Livingstone

Keyword(s):

Critical Shear Stress ◽

Eutrophic Lake ◽

Sediment Surface ◽

Storm Events ◽

Eutrophic Lakes ◽

Egg Mortality ◽

Ambient Oxygen ◽

Oxygen Gradients ◽

Egg Transport ◽

Oxygen Concentrations

Predictions based on the Shields diagram and confirmed by experiments conducted in eutrophic Lake Sempach imply that bottom currents associated with winter storm events are responsible for the simultaneous transport of coregonid eggs and fine silt and clay (grain size [Formula: see text]) from the spawning grounds into deeper lake regions. The critical shear stress required to initiate egg transport is estimated to lie in the range 0.02–0.04 N∙m−2, corresponding to mean current speeds of 10–15 cm∙s−1 at a reference height of 0.5 m above the sediment surface. On settling out, egg burial is likely. This will increase egg mortality not only by physically hindering oxygen transport to the egg, but also, in POC-rich eutrophic lake sediment, by relocating the egg in a zone of steep oxygen gradients and low mean oxygen concentrations. Microelectrode measurements and computation of the thickness of the oxygen diffusive boundary layer over the sediment reveal that even eggs that escape interment are likely to be subjected to ambient oxygen concentrations insufficient for development to hatching. It is suggested that transport and burial may in general be important factors determining coregonid egg mortality in eutrophic lakes.

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