Cited by 48Aquatic Ecosystems and Phytoplankton DynamicsMarine and coastal ecosystemsWater Quality and Resources Studies

Assessment of Long-term Trends in the Oxygen Resources of a Recovering Urban Lake, Onondaga Lake, New York

Open access
Matthews, David A., Effler, Steven W.·2006·Lake and Reservoir Management

Abstract

Long-term trends in dissolved oxygen (DO) resources are documented for ionically enriched, hypereutrophic Onondaga Lake, New York, for 1978–2002. Assessments of oxygen resources are based on DO profiles of 1 m resolution conducted hourly to weekly during April-October. Closure of an industry that operated on the lake's shore until 1986 resulted in an abrupt decrease in primary production and organic carbon deposition and marked changes in hypolimnetic and epilimnetic DO regimes. The hypolimnetic DO response was gradual, reflecting the influence of sediment feedback. The onset of complete hypolimnetic anoxia, which occurred by early June through the 1980s, took place approximately one month later over 1997–2002. The anoxic factor decreased significantly over the study interval, from 97±5 d to 67±2 d. Epilimnetic DO concentrations responded rapidly to the abrupt change in lake metabolism. Before closure of the industry, 41% of the April to mid-September DO observations deviated from saturation concentrations by >30%. In the years immediately following industry closure, this degree of disequilibrium occurred in 23% of DO observations. Percent saturation values during fall turnover increased gradually during the study, from 49±2 to 65±2. DO concentrations in the lake's upper waters have been subject to substantial diel fluctuations (>4 mg/L), with daily minima and maxima generally occurring at approximately 7:00 and 16:00, respectively. Measurements made at 11:00 and 22:00 were most likely to be representative of daily average conditions. Diel variations and sampling frequency were demonstrated to be important issues for the evaluation of status with respect to water quality standards for DO. Levels of DO in the lake's upper waters have been positively correlated with chlorophyll a concentrations (r = 0.52). Despite marked improvements in DO resources, the lake continues to lack cool, well-oxygenated waters during summer necessary to support coldwater fish species.

AI snapshot

Written from the paper’s full text.

TL;DR

Long-term monitoring of Onondaga Lake (1978–2002) shows improvements in dissolved oxygen after the 1986 soda ash facility closure, including later onset and shorter duration of hypolimnetic anoxia and higher fall upper-water DO saturation. However, severe fall lake-wide DO depletion and lack of oxygenated cool-water fish habitat persisted through 2002.

Key findings

  • Hypolimnetic anoxia duration decreased from a high of 157 days in 1981 to a low of 98 days in 1997; during 1997–2002 it averaged 101±1 days. The anoxic factor decreased significantly (p=0.001) from 97±5 days pre-closure to 67±2 days in the new quasi steady-state, and the onset of complete hypolimnetic anoxia occurred about one month later.
  • Upper-water DO became less variable, and fall percent saturation was significantly higher in 1997–2002 (65±2) than in 1978–1986 (49±2) or 1987–1996 (50±1; p<0.001). Still, DO <5 mg/L occurred throughout the water column during fall mixing in all but three study years (1999, 2000, 2001), and in 5 of 23 years DO fell below 2 mg/L.
  • In 1999, hourly upper-water DO ranged from 0.2 to 8.2 mg/L within a day; the median diel range was 1.7 mg/L, with <2 mg/L on 60% of monitored days and >4 mg/L on 9%. In 2002, monthly or bi-weekly sampling found 1 violation of the 5 mg/L daily-average standard, whereas daily sampling found 11; daily sampling found 2 violations of the 4 mg/L instantaneous standard versus none with weekly sampling.
  • Fish habitat did not substantially improve: the lake’s DO resources were no better in 2002 than in 1988 for cool-water habitat, and during July–September 2002 depths with temperatures ≤20°C were essentially devoid of DO. In October 2002, DO fell below 5 mg/L throughout the water column.

Methods

  • Onondaga Lake was monitored at its deepest location (~19.5 m) during April–October/November 1978–1982 and 1985–2002. Profiling was 2–3 times per week in some years, weekly from 1990–2000, and at least daily in 2001–2002; DO and temperature were measured at 1 m intervals with calibrated probes, plus hourly DO/temperature at 1 m during April–October 1999.
  • The anoxic factor (AF) was calculated from DO profiles, anoxic sediment area, and lake surface area according to Nürnberg (1995). Analyses used three periods: pre-closure (1978–1986), transition (1987–1996), and new quasi steady-state (1997–2002), and considered onset/duration of anoxia, AF, areal hypolimnetic oxygen deficit (AHOD), saturation deviations, seasonal and diel dynamics, standards status, and sampling frequency.
  • Statistical comparisons included Welch t-tests, correlations, and best-fit polynomial curves with coefficients of determination; sampling-frequency effects were evaluated using robotic buoy measurements from 2001 and 2002.

Limitations

  • The paper states that near-bottom anoxia metrics could not be calculated in years when complete spring turnover failed (1980, 1985, 1986, 1993, 1994), that the July 19 diel observation was excluded because probes could not measure DO above 200% saturation, and that hypolimnetic pools of oxygen-demanding reduced species were presently unquantified.
  • The paper states that diel DO patterns are rarely ideal and that sampling frequency/timing strongly affects assessment of DO standards; a measurement at 11:00, the hour most appropriate for estimating daily average, ranged from 80 to 130% of the true daily average.
  • Evident from the text: the monitoring record has a gap in 1983–1984, sampling frequency and instrumentation changed over the study, the diel analysis is limited to 1999, and the fish-habitat comparison uses only 1988 and 2002.

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

Integrity signals

Registry

Crossref · 10.1080/07438140609353881

Cites

48 of 48 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

12 of 32 cited sources checked · 9 supported · 0 flagged · accuracy not yet measured

  • Premisecitation

    Onondaga Lake supported a coldwater fishery through the late 1800s.

    “The lake supported a coldwater fishery through the late 1800s (Atlantic salmon and whitefish; Tango and Ringler 1996).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Tango and Ringler 1996 source
  • Premisecitation

    High calcium concentrations promoted coagulation in Onondaga Lake.

    “The high Ca 2+ concentrations promoted coagulation (Weilenmann et al. 1989)”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites Weilenmann et al. 1989 source

      The Abstract says calcium ions enhance natural coagulation, and the Experimental methodology says low DOC and high calcium favor coagulation. But the study focuses on Swiss lakes, chiefly Zurich and Sempach; our copy does not establish that high calcium promoted coagulation in Onondaga Lake. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • Rests on an assumption: Onondaga Lake was used as a source of cooling water and for disposal of large quantities of ionic waste (Cl-, Na+, Ca2+).
  • Premisecitation

    The soda ash facility's ionic discharge prevented complete spring turnover in Onondaga Lake in some years.

    “and in some years prevented complete spring turnover (Owens and Effler 1989;Effler and Matthews 2003).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites Owens and Effler 1989 source
    • cites Effler and Matthews 2003 source
    • Rests on an assumption: The primary industrial polluter of Onondaga Lake was a soda ash manufacturer that operated on the western shore from 1894 until 1986.
  • Premisecitation

    Onondaga Lake was oligo-mesotrophic prior to European settlement in the late 1700s.

    “Diatom stratigraphy indicates that Onondaga Lake was oligo-mesotrophic prior to European settlement in the late 1700s (Rowell 1996).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Rowell 1996 source
  • Premisecitation

    These byproducts are oxidized during the fall mixing period, causing severe depletion of dissolved oxygen (e.g., DO <5 mg/L) in the upper waters of Onondaga Lake.

    “These byproducts are oxidized during the fall mixing period, causing severe depletion of DO (e.g., DO <5 mg/L) in the upper waters (Gelda and Auer 1996).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Gelda and Auer 1996 source
  • May combine two claims. 11
  • Classified as probably not a substantial claim. 5
  • May combine two claims.

    Premisecitation

    The soda ash facility discharged more than 1.0 × 10^6 metric tons of ionic waste to Onondaga Lake annually during 1940-1986, causing the lake to be unusually saline.

    “The facility discharged >1.0 × 10 6 metric tons of ionic waste to the lake annually during 1940-1986, causing the lake to be unusually saline (Effler and Matthews 2003)”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites Effler and Matthews 2003 source

      The Abstract (p. 2) says the facility discharged about 1.3 million metric tons of ionic waste annually at peak production and identifies high salinity as an impact. The Ionic Waste section (p. 6) estimates an annual average of 1.2 million metric tons for 1974–1985, but does not establish that discharges exceeded 1.0 million metric tons every year throughout 1940–1986. The stated duration therefore overextends the evidence. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • Rests on an assumption: The primary industrial polluter of Onondaga Lake was a soda ash manufacturer that operated on the western shore from 1894 until 1986.
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Onondaga Lake was described as nearly nutrient saturated through the early 1990s.

    “Despite a 30-fold reduction in Metro's P load since the early 1970s (Effler et al. 2005), the lake was described as nearly nutrient saturated through the early 1990s (Connors et al. 1996).”
    Quote in the paperNot a substantial claim2 of 2 sources checked
    • cites Connors et al. 1996 source
    • cites Effler et al. 2005 source
  • May combine two claims.

    Premisecitation

    The closure of the soda ash industry in Onondaga Lake in 1986 resulted in an abrupt decrease in organic carbon deposition, which was likely associated with a similar decrease in primary production.

    “The closure of an industry in 1986 resulted in an abrupt decrease in organic carbon deposition that was likely associated with a similar decrease in primary production (Effler et al. 2001(Effler et al. , 2005)).”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites Effler et al. 2001 source
    • cites Effler et al. 2005 source
  • May combine two claims.

    Findingown data

    In 2002, daily sampling of Onondaga Lake indicated 2 days with epilimnetic dissolved oxygen below 4 mg/L, whereas monthly, bi-weekly, and weekly sampling indicated 0 days.

    “| Days < 4 mg/L | 0 | 0 | 0 | 2 |”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingown data

    In 2002, the fall minimum epilimnetic dissolved oxygen concentration under daily sampling was 3.6 mg/L, lower than under monthly (4.7 mg/L), bi-weekly (4.7 mg/L), and weekly (4.5 mg/L) sampling.

    “| Fall minimum | 4.7 | 4.7 | 4.5 | 3.6 |”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingown data

    In 2002, daily sampling of Onondaga Lake indicated 11 days with epilimnetic dissolved oxygen below 5 mg/L, whereas monthly and bi-weekly sampling indicated 1 day and weekly sampling indicated 2 days.

    “| Days < 5 mg/L | 1 | 1 | 2 | 11 |”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingown data

    In 2002, the range of epilimnetic dissolved oxygen under daily sampling was 3.6-14.8 mg/L, wider than under monthly (4.7-13.2 mg/L), bi-weekly (4.7-14.8 mg/L), and weekly (4.5-14.8 mg/L) sampling.

    “| range | 4.7 -13.2 | 4.7 -14.8 | 4.5 -14.8 | 3.6 -14.8 |”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Interpretationreasoning

    The time course of the improvement in fall turnover DO depletion was consistent with the gradual hypolimnetic response and indicative of sediment feedback.

    “The time course of this improvement was consistent with the gradual hypolimnetic response and indicative of sediment feedback.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Interpretationreasoning

    The change in the duration of anoxia in Onondaga Lake has been gradual, reflecting the slower processes that control sediment diagenesis.

    “The change in the duration of anoxia has been gradual, reflecting the slower processes that control sediment diagenesis.”
    Quote in the paperSubstantial claim
  • Classified as probably not a substantial claim.

    Study design and conductnone given

    Field measurements of dissolved oxygen and temperature were made at 1 m depth intervals with calibrated probes.

    “Field measurements of DO and temperature (T) were made at 1 m depth intervals with calibrated probes.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    A number of uses of Onondaga Lake have been lost, including the coldwater fishery.

    “A number of uses of the lake have been lost, including the coldwater fishery (Effler 1996).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Effler 1996 source
  • May combine two claims.

    Premisecitation

    The Onondaga County Metropolitan Sewage Treatment Plant (Metro) contributes approximately 20% of Onondaga Lake's inflow and approximately 85% of the effective phosphorus load.

    “The Onondaga County Metropolitan Sewage Treatment Plant (Metro, Fig. 1) contributes ~20% of the lake's inflow and ~85% of the effective (i.e., can support phytoplankton growth) phosphorus (P) load (Effler et al. 2002b).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Effler et al. 2002b

      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

    Recent advances in computer-driven robotic monitoring buoys and associated data management systems allow delivery of temporally detailed water quality information to lake managers in near-real-time.

    “However, recent advances in computer-driven robotic monitoring buoys and associated data management systems allow delivery of temporally detailed water quality information to lake managers in near-real-time (Effler et al. 2002a).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Effler et al. 2002a

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

  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Interpretationnone given

    Diel dissolved oxygen variations in productive lakes are coupled to levels of incident solar radiation, which vary irregularly.

    “These variations are coupled to levels of incident solar radiation, which vary irregularly.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    Numerous water quality improvements have been documented in systems where hypolimnetic oxygenation has been implemented, including increased hypolimnetic dissolved oxygen concentrations, reductions in release of nutrients and reduced chemical species from sediments, and improved habitat for fish, zooplankton and benthos.

    “Numerous water quality improvements have been documented in systems where hypolimnetic oxygenation has been implemented, including increased hypolimnetic DO concentrations, reductions in release of nutrients and reduced chemical species from sediments, and improved habitat for fish, zooplankton and benthos (Beutel and Horne 1999).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Beutel and Horne 1999 source
15 of 15
  • The paper relies on this without support.

    Metro's phosphorus load causes Onondaga Lake to be hypereutrophic, which is reflected in the lake's degraded oxygen resources.

    “Metro's P load causes the lake to be hypereutrophic, which is reflected in the lake's degraded oxygen resources.”
  • The paper relies on this without support.

    The primary industrial polluter of Onondaga Lake was a soda ash manufacturer that operated on the western shore from 1894 until 1986.

    “The primary industrial polluter of Onondaga Lake was a soda ash (Na 2 CO 3 ) manufacturer that operated on the western shore of the lake from 1894 until 1986 (Fig. 1).”
  • The paper relies on this without support.

    Onondaga Lake was used as a source of cooling water and for disposal of large quantities of ionic waste (Cl-, Na+, Ca2+).

    “The lake was used as a source of cooling water and for disposal of large quantities of ionic (Cl -, Na + , and Ca 2+ ) waste.”
  • The paper relies on this without support.

    Onondaga Lake is an alkaline, hard water, dimictic system located immediately north of Syracuse, NY.

    “Onondaga Lake is an alkaline, hard water, dimictic system located (latitude 43° 06' 54'', longitude 76° 14' 34'') immediately north of the city of Syracuse, NY (Fig. 1).”
4 of 4

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Text cites a nonexistent Figure 8c

    Minor

    The text refers to Figure 8c, but the Figure 8 caption lists only panels (a) and (b).

1 of 1

Cites

Flagged first, then by citations

Research works printed but not linked: 4

  1. Field , S. D. 1980 . Nutrient-saturated growth in hypereutrophic Onondaga Lake, Syracuse, N.Y. PhD dissertation Syracuse , NY : Dept of Civil Engineering, Syracuse University .
  2. Hutchinson , G. E. 1957 . A Treatise of Limnology Vol. I. Geography, Physics and Chemistry 1015 New York , NY : John Wiley and Sons .
  3. Petit , G. D. 1973 . Effects of dissolved oxygen on survival and behavior of selected fishes of western Lake Erie . Bull. Ohio Biol. Surv. , : 1 – 76 .
  4. Westlake , D. F. 1974 . “ Periphyton and Macrophytes. ” . In A manual on methods for measuring primary production in aquatic environments , IBP Handbook 12 Edited by: Vollenweider , R. A. 32 – 42 . Oxford : Blackwell Scientific Publications .

Cited by

Sorted by citations

Authors
Matthews, D. A., & Effler, S. W.
Affiliations
Upstate Freshwater Institute (US)
Venue
Lake and Reservoir Management
Published
2006-03
Volume
22
Issue
1
Pages
19-32
ISSN
  • 0743-8141 (ISSN-L)
  • 1040-2381
  • 2151-5530
OpenAlex
W2028982385
Cited by
48
References
47
Citations by year
2026: 1 · 2024: 1 · 2023: 2 · 2021: 2 · 2020: 3 · 2019: 4 · 2018: 2 · 2017: 2 · 2016: 2 · 2015: 6 · 2014: 1 · 2013: 2 · 2012: 4
FWCI
3.83
Type
journal article
Language
en
Open access
Locations
Lake and Reservoir Management (publishedVersion)
Topics
  • Physical Sciences › Environmental Science › Environmental Chemistry › Aquatic Ecosystems and Phytoplankton Dynamics
  • Physical Sciences › Earth and Planetary Sciences › Oceanography › Marine and coastal ecosystems
  • Physical Sciences › Environmental Science › Water Science and Technology › Water Quality and Resources Studies
Keywords
dissolved oxygen, Onondaga Lake, hypolimnetic anoxia, hypereutrophic lakes, industrial closure, lake recovery, chlorophyll a, lake metabolism, water quality standards, hypolimnetic oxygen depletion

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Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

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

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