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Cited by 15Aquatic Ecosystems and Phytoplankton DynamicsFish Ecology and Management StudiesAquatic Ecosystems and Biodiversity

Food web effects and the disappearance of the spring clear water phase in Onondaga Lake following nutrient loading reductions

Open access
Wang, Roland W., Rudstam, Lars G., Brooking, Thomas E., Snyder, David J., Arrigo, Mark A., Mills, Edward L.·2010·Lake and Reservoir Management
DOI 10.1080/07438141.2010.504070
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Abstract

The annual spring clear water phase (May–June) in Onondaga Lake, New York, unexpectedly disappeared in 2003 following several years of phosphorus and ammonia loading reductions at the Metropolitan Syracuse Wastewater Treatment Facility (Metro). Mean chlorophyll a concentration during May–June was higher from 2003 to 2007 than from 1990 to 2002, with mean Secchi disk depths <2 m. Large zooplankton (Daphnia sp.) were abundant during April–June before 2003 but were rare from 2003 to 2007, while abundance of small zooplankton (Bosmina longirostris) increased. Alewife (Alosa pseudoharengus) catches from electrofishing surveys dramatically increased in 2003, and hydroacoustic surveys estimated the alewife population to be between 1600 and 2300 fish/ha in spring 2005–2007. The alewife population in 2005 was dominated by a strong 2002 year class. Increasing biomass of the 2002 year class coincided with the timing of the shift from large to small zooplankton in late summer of 2002. This indicates that the strong 2002 alewife year class initiated a classic trophic cascade in Onondaga Lake, causing the decline and continuing low abundance of Daphnia sp. and the disappearance of the spring clear water phase. The increase in alewife may have been associated with decreasing ammonia concentrations following improvement to Metro. Unionized ammonia has been below levels considered toxic to nonsalmonid fish species since 1999, and the ammonia concentration continues to decrease in the lake. Thus, reductions in nutrient loading can lead to unanticipated food web effects causing decreases rather the expected increases in water clarity in the spring–early summer period.

AI snapshot

Written from the paper’s full text.

TL;DR

In Onondaga Lake, the spring clear water phase disappeared beginning in 2003 after nutrient loading reductions, coincident with a strong 2002 alewife year class and a shift from large Daphnia to small zooplankton. The authors conclude that increased alewife planktivory initiated a trophic cascade that reduced spring water clarity despite lower phosphorus and ammonia loading.

Key findings

  • May–June water clarity was lower and chlorophyll a higher in 2003–2007 than in 1990–2002: mean Secchi depth 1.7 m (1.5–2.0 m) vs. 3.5 m (2.5–4.2 m), and mean chl-a 18.9 µg/L (10.3–28.9 µg/L) vs. 7.5 µg/L (2.7–13.6 µg/L), excluding 1994 and 2000.
  • Daphnia spp. dominated before August 2002 but disappeared in late summer 2002; small cladocera, especially Bosmina longirostris, became abundant. Mean zooplankton size fell from 0.92 mm in spring 2002 to 0.29 mm in fall 2002 (data not shown).
  • Alewife catches increased starting in 2003; hydroacoustic surveys estimated 1600–2300 fish/ha in spring 2005–2007, and the 2005 population was dominated by the strong 2002 year class. The spring 2005 population was estimated at 2.6 million fish (1170 ha × 2242 fish/ha).
  • In-lake total phosphorus declined from 180 µg/L in 1993 to 30 µg/L in 2007; total ammonia peaked at 2.5 mg N/L in 1995 and fell to 0.15 mg N/L in 2007. Unionized NH3 remained below 0.02 mg N/L since 2000 and below 0.004 mg N/L from 2004 to 2007, which the authors suggest improved alewife recruitment.

Methods

  • Used Onondaga County Ambient Monitoring Program data from 1990–2007 for total phosphorus, total ammonia, Secchi depth, chlorophyll a, and zooplankton; zooplankton composition was examined from 2000–2007. Unionized NH3 was calculated for June–July 1990–2007 and compared with USEPA’s final chronic value for nonsalmonid fishes.
  • Fish sampling included night boat electrofishing in May along 12 transects (2004 had 16 transects because of a May boat failure), multimesh vertical gill nets in 2004–2007, and hydroacoustic surveys in 2005–2007 using Simrad EY500/EY60 units with a 70 kHz transducer. Alewives from gill nets were aged using otoliths.
  • Analysis compared pre-2003 and 2003–2007 time series and linked the 2002 alewife year class to the zooplankton shift and loss of the spring clear water phase.

Limitations

  • Paper-stated: nearshore electrofishing can give biased alewife estimates, and 2004 electrofishing catch may be biased high because alewife spawn inshore in June and 2004 had 16 transects. Hydroacoustic estimates corrected for fish in the top 2 m using vertical gill net proportions.
  • Paper-stated: the authors could not find ammonia toxicity studies specific to alewife, so the ammonia–recruitment inference relies on other clupeid and nonsalmonid toxicity information.
  • Evident from the text: the conclusions rest on observational time-series correlations rather than experimental manipulation or direct consumption estimates; the alternative of large-scale immigration from Otisco Lake is argued to be unlikely but not fully excluded.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1080/07438141.2010.504070

Cites

33 of 33 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

3 of 42 cited sources checked · 3 supported · 0 flagged

  • Premisecitation

    Phytoplankton biomass depends both on nutrient availability and grazing pressure from large-bodied zooplankton like Daphnia.

    “Phytoplankton biomass depends both on nutrient availability and grazing pressure from large bodied zooplankton like Daphnia (Brooks and Dodson 1965, Carpenter and Kitchell 1984, Lampert et al. 1986, McQueen et al. 1986).”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites Brooks and Dodson 1965 source
    • cites Carpenter and Kitchell 1984 source
    • cites Lampert et al. 1986 source
  • Premisecitation

    The timing and extent of the spring clear water phase correlates with peak Daphnia abundance.

    “In particular, the timing and extent of the spring clear water phase cor-relates with peak Daphnia abundance (Lampert et al. 1986, Sommer et al. 1986, Rudstam et al. 1993, Meijer et al. 1999).”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites Lampert et al. 1986 source
    • cites Sommer et al. 1986 source
    • cites Rudstam et al. 1993 source
  • Findingown data

    The alewife population in Onondaga Lake in 2005 was dominated by a strong 2002 year class.

    “The alewife population in 2005 was dominated by a strong 2002 year class.”
    Quote in the paperSubstantial claim
  • Findingown data

    Calculated peak concentration of unionized NH3 in June-July was 0.116 mg N/L in 1995.

    “Calculated peak concentration of unionized NH 3 in June-July was 0.116 mg N/L (1995).”
    Quote in the paperNot a substantial claim
  • Findingnone given

    From March 2000 to August 2002, zooplankton biomass was dominated by large cladocera, specifically Daphnia mendotae.

    “From March 2000 to August 2002, zooplankton biomass was dominated by large cladocera, specifically Daphnia mendotae.”
    Quote in the paperSubstantial claim
  • Classified as probably not a substantial claim. 11
  • May combine two claims. 25
  • The quote only partly states this claim. 2

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation

    Acoustic returns from targets larger than -60 dB were analyzed with EchoView software using standard methods.

    “Acoustic returns from targets larger than -60 dB were analyzed with the EchoView software (version 4.40; Myriax 2008) using standard methods (Rudstam et al. 2009).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Rudstam et al. 2009 source

  • May combine two claims. The quote only partly states this claim.

    Findingown data

    Small cladocera were uncommon in the lake while cyclopoid and calanoid copepods were moderately abundant from March 2000 to August 2002.

    “Small cladocera were uncommon in the lake while cyclopoid and calanoid copepods were moderately abundant.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    After August 2002, large cladocera and calanoid copepods disappeared while small cladocera, specifically Bosmina longirostris, became very abundant.

    “After August 2002, large cladocera and calanoid copepods disappeared while small cladocera, specifically Bosmina longirostris, became very abundant”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Most of the fish caught in vertical gill nets were alewife, which dominated catches.

    “Most of these fish were alewife, which dominated catches in the vertical gill nets.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Excluding 1994 and 2000, mean spring water clarity from 1990 to 2002 was 3.5 m (range 2.5-4.2 m), consistent with relatively low chl-a concentration in those years (mean = 7.5 μg/L, range = 2.7-13.6 μg/L).

    “Excluding 1994 and 2000, mean spring water clarity from 1990 to 2002 was 3.5 m (2.5-4.2 m), which is consistent with relatively low chl-a concentration in those years (mean = 7.5 µg/L, range = 2.7-13.6 µg/L).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingreasoning

    The Metro is still a primary source of ammonia loading into Onondaga Lake, but reductions in loading since the mid-1990s have been dramatic, reflecting improvements to the facility.

    “The Metro is still a primary source of ammonia loading into the lake, but the reductions in loading since the mid-1990s have been dramatic, reflecting improvements to the facility.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Large zooplankton (Daphnia sp.) were abundant during April-June in Onondaga Lake before 2003 but were rare from 2003 to 2007.

    “Large zooplankton (Daphnia sp.) were abundant during April-June before 2003 but were rare from 2003 to 2007, while abundance of small zooplankton (Bosmina longirostris) increased.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Spring water clarity was lower and chl-a level was higher in 2003-2007 with a mean Secchi disk depth of 1.7 m (1.5-2.0 m) and a mean chl-a concentration of 18.9 μg/L (10.3-28.9 μg/L).

    “Spring water clarity was lower and chl-a level was higher in 2003-2007 with a mean Secchi disk depth of 1.7 m (1.5-2.0 m) and a mean chl-a concentration of 18.9 µg/L (10.3-28.9µg/L).”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingreasoning

    Unionized NH3 concentrations were a lower proportion of T-NH3 in 1990, 1991, and 1994 than in other years due to effects of pH and temperature on the amount of ammonia present in the unionized state.

    “Unionized NH 3 concentrations were a lower proportion of T-NH 3 in 1990, 1991, and 1994 than in the other years due to the effects of pH and temperature on the amount of ammonia present in the unionized state.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Since 1995, unionized NH3 concentration has declined and remained below 0.02 mg N/L since 2000 and below 0.004 mg N/L from 2004 to 2007.

    “Since 1995, unionized NH 3 concentration has declined and has remained below 0.02 mg N/L since 2000 and below 0.004 mg N/L from 2004 to 2007.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    In-lake mean annual total ammonia (T-NH3) increased from 1990 to a peak concentration of 2.5 mg N/L in 1995 and then decreased to a low of 0.15 mg N/L in 2007.

    “In-lake mean annual T-NH 3 increased from 1990 to a peak concentration of 2.5 mg N/L in 1995 and then decreased to a low of 0.15 mg N/L in 2007”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    With the closure of Allied Chemical's plant in Syracuse in 1987 and continued improvements to the Metro, unionized NH3 concentration declined to <0.02 mg N/L beginning in 2000.

    “With the closure of Allied Chemical's plant in Syracuse in 1987 and the continued improvements to the Metro, unionized NH 3 concentration declined to <0.02 mg N/L beginning in 2000 (Fig. 2).”
    Quote in the paperSubstantial claim

  • May combine two claims. The quote only partly states this claim.

    Findingnone given

    Cyclopoid copepods declined but remained in the lake throughout the time period.

    “Cyclopoid copepods declined but re-”
    • Also stated in: § Discussion · plain
      “mained in the lake throughout the time period.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning

    Because alewife spawn inshore in June, the catch per transect in 2004 may be biased high compared to other years.

    “Because alewife spawn inshore in June, the catch per transect in 2004 may be biased high compared to the other years.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    The strong 2002 alewife year class initiated a classic trophic cascade in Onondaga Lake, causing the decline and continuing low abundance of Daphnia sp. and the disappearance of the spring clear water phase.

    “This indicates that the strong 2002 alewife year class initiated a classic trophic cascade in Onondaga Lake, causing the decline and continuing low abundance of Daphnia sp. and the disappearance of the spring clear water phase.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Alewife is an efficient planktivore that often collapses abundant populations of large zooplankton.

  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    Alewife is an offshore species found mainly nearshore during spawning.

    “Alewife is an offshore species found mainly nearshore during spawning (Klumb et al. 2003, Werner 2004).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites Klumb et al. 2003 source
    • cites Werner 2004 source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Onondaga Lake flushes rapidly (4 times/y) and responds quickly to changes in external loading.

    “The lake flushes rapidly (4 times/y) and responds quickly to changes in external loading (Matthews et al. 2001).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Matthews et al. 2001 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The quality of Onondaga Lake has improved substantially during the past 20 years as a result of closures of several industries and improvements to the Metro.

    “The quality of the lake has improved substantially during the past 20 years as a result of closures of several industries and improvements to the Metro (OCDWEP 2008).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites OCDWEP 2008

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    The spring clear water phase ends as predation on Daphnia by planktivorous fish and invertebrates increases through spring and early summer, causing Daphnia populations to decline and phytoplankton biomass to increase.

    “This clear water phase ends as predation on Daphnia by planktivorous fish and invertebrates increase through spring and early summer, causing Daphnia populations to decline and phytoplankton biomass to increase (Sommer et al. 1986).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Sommer et al. 1986 source

  • May combine two claims.

    Premisecitation

    The Metro currently accounts for approximately 15-20% of the annual flow into Onondaga Lake and, until recently, was the dominant source of total phosphorus and total ammonia loading.

    “The Metro currently accounts for approximately 15-20% of the annual flow into the lake and, until recently, was the dominant source of TP and T-NH 3 loading (OCDWEP 2008).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites OCDWEP 2008

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    In lakes with anadromous alewife, the shift to smaller zooplankton occurs only during summer and fall when predation from age-0 alewife is greatest.

    “In contrast, lakes with anadromous alewife shift to smaller zooplankton only during summer and fall when predation from age-0 alewife is greatest (Post et al. 2008).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Post et al. 2008 source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductnone given

    Both hydroacoustic units used the same 70 kHz transducer that was calibrated with a standard target (-39.2 dB copper sphere) before each survey.

    “Both units used the same 70 kHz transducer that was calibrated with a standard target (-39.2dB copper sphere) before each survey.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Adult freshwater fish are susceptible to unionized NH3 toxicity at 0.068-2 mg N/L (96 h LC50), and larval stages are likely more vulnerable.

    “Adult freshwater fish are susceptible to unionized NH 3 toxicity at 0.068-2 mg N/L (96 h LC 50 ), and the larval stages are likely more vulnerable (see review by Eddy 2005).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Eddy 2005 source

  • May combine two claims.

    Interpretationreasoning

    The authors believe that the ammonia removal by the Metro improved conditions for alewife recruitment and set the stage for the production of a strong year class in 2002.

    “We believe this is what happened in 2002.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    Such a small number of fish may be hard to detect in a lake the size of Onondaga Lake, and given that they were detected in the spring of 2001 and 2002, the population size was likely substantially larger at that time.

    “Such a small number of fish may be hard to detect in a lake the size of Onondaga Lake, and given that they were detected in the spring of 2001 and 2002 (Table 1), the population size was likely substantially larger at that time.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    The lake had a high salt content, but this decreased at the end of the 1980s, which led to the return of native Daphnia species (D. pulicaria, D. ambigua, and D. mendotae) as well as the decline of 2 salt tolerant, exotic Daphnia species (D. elixis and D. curvirostris).

    “The lake had a high salt content, but this decreased at the end of the 1980s, which led to the return of native Daphnia species (D. pulicaria, D. ambigua, and D. mendotae) as well as the decline of 2 salt tolerant, exotic Daphnia species (D. elixis and D. curvirostris; Duffy et al. 2000, Hairston et al. 2005).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites Duffy et al. 2000 source
    • cites Hairston et al. 2005 source

  • Classified as probably not a substantial claim.

    Study design and conductown data

    Fish in the top 2 m of water not accessible to acoustics were accounted for using the proportion of fish caught in 0-2 m relative to 2-6 m in vertical gill nets.

    “We accounted for fish in the top 2 m of water that is not accessible to acoustics using the proportion of fish caught in 0-2 m relative to the proportion of fish caught in 2-6 m in our vertical gill nets.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    The ammonia removal by the Metro is likely to have improved the conditions for alewife recruitment in the lake and set the stage for the production of a strong year class.

    “If so, the ammonia removal by the Metro is likely to have improved the conditions for alewife recruitment in the lake and set the stage for the production of a strong year class.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The toxicity of unionized ammonia to alewife is similar to that observed for marine herring, so herring toxicity data can be used to infer effects on alewife.

  • May combine two claims.

    Interpretationreasoning

    The only alternative to resident production is a large-scale immigration event of age-0 alewife in 2002 or age-1 alewife in early spring of 2003.

    “The only alternative is a large-scale immigration event of age-0 alewife in 2002 or age-1 alewife in early spring of 2003 because alewives were abundant in the EF survey during spring of 2003.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    Otisco Lake is unlikely to have supported such a large number of surplus fish, and it is also unlikely that such a large scale migration event would have gone unnoticed.

    “Otisco Lake is unlikely to have supported such a large number of surplus fish, and it is also unlikely that such a large scale migration event would have gone unnoticed.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The only upstream source of alewife to Onondaga Lake is Otisco Lake.
    • Rests on an assumption: Otisco Lake is smaller than Onondaga Lake.

  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    Another clupeid, the marine herring, had lower hatching success in laboratory cultures at unionized NH3 concentrations from 0.004 to 0.019 mg N/L and higher larval mortality (LT50) at 0.014-0.019 mg N/L.

    “Costello and Gamble (1992) showed that another clupeid, the marine herring (Clupea harengus) had lower hatching success in laboratory cultures at unionized NH 3 concentrations from 0.004 to 0.019 mg N/L and higher larval mortality (LT 50 ) at 0.014-0.019mg N/L.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Costello and Gamble (1992) source

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationnone given

    Food web changes that may result from nutrient reductions can have a significant impact on lake conditions and public perceptions of water quality.

    “Our analysis of Onondaga Lake stresses the importance of evaluating food webs changes that may result from nutrient reductions because food web effects can have a significant impact on lake conditions and public perceptions of water quality.”
    Quote in the paperNot a substantial claim
32 of 32

  • The paper relies on this without support.

    Alewife is an efficient planktivore that often collapses abundant populations of large zooplankton.

    “Alewife (Alosa pseudoharengus) is an efficient planktivore, often collapsing abundant populations of large zooplankton.”

  • The paper relies on this without support.

    The toxicity of unionized ammonia to alewife is similar to that observed for marine herring, so herring toxicity data can be used to infer effects on alewife.

    “Although we could not find ammonia toxicity studies specific for alewife, Costello and Gamble (1992) showed that another clupeid, the marine herring (Clupea harengus) had lower hatching success in laboratory cultures at unionized NH 3 concentrations from 0.004 to 0.019 mg N/L and higher larval mortality (LT 50 ) at 0.014-0.019mg N/L.”

  • The paper relies on this without support.

    The only upstream source of alewife to Onondaga Lake is Otisco Lake.

    “The only upstream source of alewife is Otisco Lake, which is smaller than Onondaga Lake.”

  • The paper relies on this without support.

    Otisco Lake is smaller than Onondaga Lake.

    “The only upstream source of alewife is Otisco Lake, which is smaller than Onondaga Lake.”
4 of 4

Cites

Flagged first, then by citations

Research works printed but not linked: 4

  1. Myriax, 2008, EchoView 4.40. Myriax Software Pty
  2. [OCDWEP] Onondaga County Department of Water Environment Protection, 2008, Onondaga Lake ambient monitoring program: 2007 annual report final. Onondaga County, Syracuse (NY)
  3. [USEPA] United States Environmental Protection Agency, 1985, Ambient water quality criteria for ammonia - 1984
  4. [USEPA] United States Environmental Protection Agency, 2003, Standard operating procedure for zooplankton analysis

Cited by

Sorted by citations

Related

Authors
Wang, R. W., Rudstam, L. G., Brooking, T. E., Snyder, D. J., Arrigo, M. A., & Mills, E. L.
Affiliations
Cornell University (US)
ORCID
Rudstam, Lars G.
Venue
Lake and Reservoir Management
Publisher
Informa UK Limited
Published
2010-08-16
Volume
26
Issue
3
Pages
169-177
ISSN
  • 0743-8141 (ISSN-L)
  • 1040-2381
  • 2151-5530
DOI
10.1080/07438141.2010.504070
OpenAlex
W2021553076
Semantic Scholar
14841a7b17de273da1d08b752540620e031129b6
Cited by
15
References
33
Citations by year
2020: 1 · 2018: 1 · 2016: 1 · 2015: 6 · 2014: 2 · 2012: 1
FWCI
1.04
Type
journal article
Language
en
Open access
Locations
Lake and Reservoir Management (publishedVersion)
Funders
Cornell University Agricultural Experiment Station
Topics
  • Physical Sciences › Environmental Science › Environmental Chemistry › Aquatic Ecosystems and Phytoplankton Dynamics
  • Physical Sciences › Environmental Science › Nature and Landscape Conservation › Fish Ecology and Management Studies
  • Physical Sciences › Environmental Science › Ecology › Aquatic Ecosystems and Biodiversity
Keywords
Onondaga Lake, trophic cascades, alewife, Daphnia, Bosmina longirostris, zooplankton abundance, nutrient load reduction, phosphorus loading, ammonia loading, chlorophyll a, Secchi depth, water transparency, food web effects, year-class abundance, wastewater treatment plants

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Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-16.

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