Rights statement: This is the author’s version of a work that was accepted for publication in Applied Geochemistry. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Applied Geochemistry, 95, 2018 DOI: 10.1016/j.apgeochem.2018.05.025
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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - Evaluating the stable isotopic composition of phosphate oxygen as a tracer of phosphorus from waste water treatment works
AU - Gooddy, Daren C.
AU - Bowes, Michael J.
AU - Lapworth, Dan J.
AU - Lamb, Angela L.
AU - Williams, Peter J.
AU - Newton, Rob J.
AU - Davies, Ceri L.
AU - Surridge, Ben W.J.
N1 - This is the author’s version of a work that was accepted for publication in Applied Geochemistry. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Applied Geochemistry, 95, 2018 DOI: 10.1016/j.apgeochem.2018.05.025
PY - 2018/8
Y1 - 2018/8
N2 - Eutrophication is a globally significant challenge facing freshwater ecosystems and is closely associated with anthropogenic enrichment of phosphorus (P) in the aquatic environment. Phosphorus inputs to rivers are usually dominated by diffuse sources related to farming activities and point sources such as waste water treatment works (WwTW). The limited availability of inherent labels for different P sources has constrained understanding of these triggers for eutrophication in natural systems. There have been substantial recent advances in the use of phosphate oxygen isotopes (δ18OPO4) as a way of understanding phosphate sources and processing. Results from all previous studies of the δ18OPO4 composition of WwTW effluent and septic tanks are combined together with significant new data from the UK to assess δ18OPO4 compositions in waste water sources. The overall average δ18OPO4 value is 13.9‰, ranging from 8.4 to 19.7‰. Values measured in the USA are much lower than those measured in Europe. A strong positive correlation exists between δ18OPO4 and δ18OH2O, suggesting biologically-mediated exchange between the water molecules and the phosphate ions. A comparison of δ18OPO4 and the offset from isotopic equilibrium showed a strong positive linear correlation (ρ = 0.94) for the data from Europe but no relationship for the historic USA data which may be due to recent advances in the extraction procedure or to a relative paucity of data. This offset is most strongly controlled by the δ18OH2O rather than temperature, with greater offsets occurring with lower δ18OH2O. Time series data collected over 8–24 h for three sites showed that, although there were significant changes in the phosphate concentration, for a given WwTW the δ18OPO4 stayed relatively constant. Two new studies that considered instream processing of δ18OPO4 downstream of WwTWs showed mixing of the upstream source with effluent water but no evidence of biological cycling 3 km downstream. It is suggested that δ18OPO4 can be an effective tool to trace P from WwTWs provided the source of the effluent is known and samples are collected within a day.
AB - Eutrophication is a globally significant challenge facing freshwater ecosystems and is closely associated with anthropogenic enrichment of phosphorus (P) in the aquatic environment. Phosphorus inputs to rivers are usually dominated by diffuse sources related to farming activities and point sources such as waste water treatment works (WwTW). The limited availability of inherent labels for different P sources has constrained understanding of these triggers for eutrophication in natural systems. There have been substantial recent advances in the use of phosphate oxygen isotopes (δ18OPO4) as a way of understanding phosphate sources and processing. Results from all previous studies of the δ18OPO4 composition of WwTW effluent and septic tanks are combined together with significant new data from the UK to assess δ18OPO4 compositions in waste water sources. The overall average δ18OPO4 value is 13.9‰, ranging from 8.4 to 19.7‰. Values measured in the USA are much lower than those measured in Europe. A strong positive correlation exists between δ18OPO4 and δ18OH2O, suggesting biologically-mediated exchange between the water molecules and the phosphate ions. A comparison of δ18OPO4 and the offset from isotopic equilibrium showed a strong positive linear correlation (ρ = 0.94) for the data from Europe but no relationship for the historic USA data which may be due to recent advances in the extraction procedure or to a relative paucity of data. This offset is most strongly controlled by the δ18OH2O rather than temperature, with greater offsets occurring with lower δ18OH2O. Time series data collected over 8–24 h for three sites showed that, although there were significant changes in the phosphate concentration, for a given WwTW the δ18OPO4 stayed relatively constant. Two new studies that considered instream processing of δ18OPO4 downstream of WwTWs showed mixing of the upstream source with effluent water but no evidence of biological cycling 3 km downstream. It is suggested that δ18OPO4 can be an effective tool to trace P from WwTWs provided the source of the effluent is known and samples are collected within a day.
KW - Eutrophication
KW - Phosphate oxygen isotopes
KW - Biogeochemical cycling
KW - Waste water
KW - Rivers
U2 - 10.1016/j.apgeochem.2018.05.025
DO - 10.1016/j.apgeochem.2018.05.025
M3 - Journal article
VL - 95
SP - 139
EP - 146
JO - Applied Geochemistry
JF - Applied Geochemistry
SN - 0883-2927
ER -