Enhanced mobility of Pb in the presence of dissolved natural organic matter

Jordan, Ryan N.; Yonge, David R.; Hathhorn, Wade E.

doi:10.1016/s0169-7722(96)00087-3

Cited by 82 publications

(34 citation statements)

References 23 publications

(19 reference statements)

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“…If discrimination of different DOM sources is possible, this might help improve our understanding of the chemical and structural processes generating these variations in DOM properties. Understanding DOM properties and their interactions in the environment would lead to improved understanding of DOM function, such as proton binding, metal ion, pesticide and polycyclic aromatic hydrocarbon interactions (Jordan et al, 1997, MacDonald et al, 1997 and the effect of DOM on ecosystem functions (Band et al, 2001).…”

Section: Introductionmentioning

confidence: 99%

Spectrophotometric discrimination of river dissolved organic matter

Baker

2002

Hydrological Processes

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Abstract:There is a need to be able to differentiate the dissolved organic matter (DOM) fraction in river waters. Research in the 1970s and 1980s has attempted to utilize both absorbance and fluorescence to distinguish between DOM fractions in river waters, but both were limited by the available technology. Total organic carbon content has, therefore, been widely used as a standard method of measuring DOM concentration, although it has little power to differentiate DOM fractions. Recent advances in fluorescence spectrophotometry enable rapid and optically precise analysis of DOM. Here, we show how a combination of both fluorescence and absorbance can be used to discriminate statistically between spatial variations of DOM in tributaries in a small catchment of the Ouseburn, NE England. The results of the discriminant analysis suggest that about 70% of the samples can be correctly classified to its tributary. Discriminant function 1 explains 60Ð8% of the variance in the data and the fulvic-like fluorescence intensity has the largest absolute correlation within this function; discriminant function 2 explains a further 21Ð5% of the variance and the fulvic-like fluorescence emission wavelength has the largest absolute correlation within this function. The discriminant analysis does not correctly classify all tributaries every time, and successfully discriminates between the different tributaries 70% of the time. Occasions when the tributary waters are less well discriminated are due to either episodic pollution events (at two sites) or due to tributaries that have strong seasonal trends in spectrophotometric parameters, which allows the sites to be misclassified. Results suggest that spectrophotometric techniques have considerable potential in the discrimination of DOM in rivers.

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Section: Introductionmentioning

confidence: 99%

Spectrophotometric discrimination of river dissolved organic matter

Baker

2002

Hydrological Processes

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“…Greater tailing is observed at lower pH and higher ionic strength. contaminants, including heavy metals, radionuclides, and aromatic hydrocarbons ( Johnson and Amy, 1995;Jordan et al, 1997;McCarthy, 1998;Wernert et al, 2003), and different components of NOM have different affinities not only for mineral surfaces but also for various contaminants . The CTRW model should ultimately provide a more reliable framework than the traditional ADE model for predicting transport of NOM-bound contaminants in the laboratory and in the field.…”

Section: Discussionmentioning

confidence: 99%

Natural Organic Matter Transport Modeling with a Continuous Time Random Walk Approach

McInnis

Bolster

Maurice

2014

Environmental Engineering Science

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In transport experiments through columns packed with naturally Fe/Al oxide-coated quartz sand, breakthrough curves (BTCs) of natural organic matter (NOM) displayed strong and persistent power law tailing that could not be described by the classical advection-dispersion equation. Tailing was not observed in BTCs for a nonreactive tracer (sulforhodamine B); therefore, the anomalous transport is attributed to diverse adsorptive behavior of the polydisperse NOM sample rather than to physical heterogeneity of the porous medium. NOM BTC tailing became more pronounced with decreases in pH and increases in ionic strength, conditions previously shown to be associated with enhanced preferential adsorption of intermediate to high molecular weight NOM components. Drawing from previous work on anomalous solute transport, we develop an approach to model NOM transport within the framework of a continuous time random walk (CTRW) and show that under all conditions examined, the CTRW model is able to capture tailing of NOM BTCs by accounting for differences in transport rates of NOM fractions through a distribution of effective retardation factors. These results demonstrate the importance of considering effects of adsorptive fractionation on NOM mobility, and illustrate the ability of the CTRW model to describe transport of a multicomponent solute.

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“…Understanding OM properties and their interactions in the environment can lead to a better understanding of dissolved and particulate OM properties, such as proton and metal ion binding, pesticide and polycyclic aromatic hydrocarbon interactions [41][42] and the effect of OM on the ecosystem [43]. Total organic carbon concentration has been widely used as a classical method for measuring OM [44], although it has little discriminatory power since it cannot distinguish between carbon fractions.…”

Section: Solid Phasementioning

confidence: 99%