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Title: Water colour and humic charge final report
Author: J.F. Talling
Author: S.I. Heaney
Document Type: Monograph
The objective of this work was to investigate the possible relationship between the net electrical charge on soil humic substances (HS) and the concentration of HS dissolved in the soil solution. The starting hypothesis is that the greater is the net charge (Z), the greater is the humic 'solubility'. Preliminary author's work suggests that there may be a direct relationship between Z and solution [HS]. If so, this relationship might be exploited to make quantitative predictions of concentrations of HS in drainage waters, and how they would change with climate, liming, land-use etc. Since dissolved HS are major contributors to perceived "water colour", this would be useful in the management of peaty catchments and their reservoirs. To obtain the data required to test the charge/'colour' relationship, 30 organic soil samples from various locations in England and Wales were taken and subjected to bulk analysis and acid-base titrations (in aqueous suspension). For each titration point (approx. 400 in all) the net humic charge was calculated using the model CHAOS (Complexation by Humic Acids in Organic Soils), and the calculated charges were compared with the concentrations of dissolved organic carbon (DOC) in the supernatant solutions in equilibrium with the soils.
Publisher: Freshwater Biological Association
Publication Date: 1988
Publication Place: Ambleside
Subject Keywords: Water analysisSoil chemistryHumusClimateColourTitrimetryDissolved organic carbonSamplingSoil surveysSoil propertiesModelling
Geographic Keywords: EnglandWales
Extent: 12; + tables and figures
Total file downloads: 198

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