Long-term phosphorus budgets and an examination of a steady-state mass balance model for central Ontario lakes

AbstractThe re-analysis of long-term mass-balance time series is important to provide bias-corrected mass-balance data for climate-change impact studies. A method to homogenize time series of comprehensive mass-balance monitoring programmes is presented and applied to the nearly 50 year mass-balance records of Griesgletscher and Silvrettagletscher, Switzerland. Using a distributed mass-balance model in daily resolution we correct the mass-balance data for varying observation dates. Direct point measurements are combined with independent geodetic mass changes, a prerequisite for a thorough homogenization of mass-balance records. Differences between mass balance evaluated in the hydrological year or according to the measurement period and the stratigraphic system are analysed and may be up to ±0.5mw.e. a−1. Cumulative mass balance of both glaciers based on the glaciological method generally agrees well with geodetic mass change on the investigated glaciers. However, for Silvretta-gletscher a significant bias of +0.37mw.e. a−1 has been detected and corrected for since 1994.

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A steady-state mass balance model of the polycarbonate-CO2 system reveals a self-regulating cell growth mechanism in the solid-state microcellular process

Journal of Polymer Science Part B Polymer Physics ◽

10.1002/polb.1061 ◽

2001 ◽

Vol 39 (8) ◽

pp. 868-880 ◽

Cited By ~ 19

Author(s):

M. R. Holl ◽

J. L. Garbini ◽

W. R. Murray ◽

V. Kumar

Keyword(s):

Steady State ◽

Solid State ◽

Cell Growth ◽

Mass Balance ◽

Growth Mechanism ◽

Balance Model ◽

Mass Balance Model

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Steady-State Mass Balance Model for Predicting Particle–Gas Concentration Ratios of PBDEs

Environmental Science & Technology ◽

10.1021/acs.est.0c04368 ◽

2020 ◽

Author(s):

Fangyuan Zhao ◽

Ilona Riipinen ◽

Matthew MacLeod

Keyword(s):

Steady State ◽

Mass Balance ◽

Balance Model ◽

Mass Balance Model ◽

Gas Concentration ◽

Concentration Ratios

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Field Application of a Steady-State Mass Balance Model for Hydrophobic Organic Chemicals in an Estuarine System

Water Science & Technology ◽

10.2166/wst.1993.0625 ◽

1993 ◽

Vol 28 (8-9) ◽

pp. 263-271 ◽

Cited By ~ 1

Author(s):

D. W. Dilks ◽

J. S. Helfand ◽

V. J. Bierman ◽

L. Burkhard

Keyword(s):

Steady State ◽

Mass Balance ◽

Sediment Quality ◽

Time Variable ◽

Balance Model ◽

Mass Balance Model ◽

Hydrophobic Organic Chemicals ◽

Modeling Effort ◽

Discharge Canal ◽

Receiving Water

A one-dimensional, steady-state mass balance model was applied to describe instream and sediment concentrations of four hydrophobic organic chemicals in a discharge canal and receiving water bayou. The chemicals examined were hexachlorobenzene, hexachlorobutadiene, hexachloroethane, and 1,2,4-trichlorobenzene. The objective of the study was to test a mass balance modeling approach for relating point source effluents to resulting sediment concentration, in support of future implementation of national sediment quality criteria (SQC). The modeling effort relied upon ambient monitoring data that were collected for purposes other than supporting a modeling effort. Given data uncertainties and assumptions in the modeling framework, model results were reasonably consistent with observations in the receiving water bayou. There were large discrepancies between model results and observed sediment concentrations in the discharge canal. These discrepancies are likely caused by an undocumented source of chemicals to the canal sediments, due to historical landfilling of wastes; and/or canal sediment concentrations being in temporal disequilibrium, due to historically higher chemical loading. The merits of steady-state versus time-variable models for describing sediment quality are compared. Steady-state models are most appropriate for effluent permitting purposes, where the objective is to determine the long-term relationship jbetween wastewater loads and resulting sediment concentrations. A time-variable model framework will be required to establish model credibility for situations where the steady-state assumption is violated, although the required information on historical chemical loads is often unavailable.

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Steady State Phosphorus Mass Balance Model during Hemodialysis Based on a Pseudo One-Compartment Kinetic Model

The International Journal of Artificial Organs ◽

10.1177/039139881203501102 ◽

2012 ◽

Vol 35 (11) ◽

pp. 969-980 ◽

Cited By ~ 4

Author(s):

John K. Leypoldt ◽

Baris U. Agar ◽

Alp Akonur ◽

Mary E. Gellens ◽

Bruce F. Culleton

Keyword(s):

Steady State ◽

Kinetic Model ◽

Mass Balance ◽

Balance Model ◽

Mass Balance Model ◽

Phosphorus Mass Balance

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Quantifying flood-water impacts on a lake water budget via volume-dependent transient stable isotope mass balance

10.5194/hess-2020-101 ◽

2020 ◽

Author(s):

Janie Masse-Dufresne ◽

Florent Barbecot ◽

Paul Baudron ◽

John Gibson

Keyword(s):

Surface Water ◽

Mass Balance ◽

Balance Model ◽

Water Fluxes ◽

Mass Balance Model ◽

Surface Water Pollution ◽

Flood Water ◽

Isotope Mass Balance ◽

Annual Water

Abstract. Interactions between groundwater and surface water are often overlooked in lake water budgets, even though groundwater can significantly contribute to the total annual water inputs to a lake. Isotope mass balance models have seen significant developments in the last decade for assessing the spatial and temporal variability of hydrological processes in lakes but are generally applied assuming steady-state. While this assumption is generally acceptable for long-term water balances of large lakes, it may be less appropriate for lakes which undergo strong seasonality of hydrological processes and meteorological conditions. In this study, a volume-dependent transient isotopic mass balance model was developed for an artificial lake (named Lake A) in Canada, and in a context where direct measurement of surface water fluxes is difficult, if not impossible. This lake typically receives important inputs of flood-water during the spring freshet period, as a hydraulic connection with a large watershed establishes each year. Quantification of the water fluxes to Lake A allowed to highlight the impacts of flood-water inputs over the annual water budget. The isotopic mass balance model revealed that groundwater and surface water inputs respectively account for 71 % and 28 % of the total annual water inputs to Lake A, which demonstrates its dependence on groundwater. An important part of these groundwater inputs is likely to correspond to flood-derived surface water due to bank storage. On an annual timescale, Lake A was found to be resilient to surface water pollution and sensitive to groundwater quantity and quality changes. There is however a likelihood that the resilience to surface water pollution is lower from April to August, as important water inputs originating from Lake DM contribute to the water balance via direct and indirect inputs (i.e., from bank storage). This suggests that the surface water fluxes between Lake DM and Lake A did not only have an impact on the dynamic of Lake A during springtime but also significantly influenced the long-term dynamics of Lake A. These findings can help anticipating the impacts of variation in the intensity and/or duration of future flooding events on lakes' water quality. From a more global perspective, this knowledge is useful for establishing regional-scale management strategies for maintaining water quality at flood-affected lakes in a context of land-use and climate changes.

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