Degradation of phosphorus-containing natural organic matter facilitates enrichment of geogenic phosphorus in Quaternary aquifer systems: A molecular perspective

Coupled Processes Involving Organic Matter and Fe Oxyhydroxides Control Geogenic Phosphorus Enrichment in Groundwater Systems: New Evidence from FT-ICR-MS and XANES

“…In previous studies, , TDP concentrations observed in the surrounding groundwater of the critical layer of the two typical boreholes in each plain widely varied (i.e., TDP in JH1-CL: 7.0 mg/L, in JH2-CL: 0.2 mg/L, in DT1-CL: 3.6 mg/L, and in DT2-CL: 0.09 mg/L). Elevated groundwater TDP concentrations in the critical layer are less related to anthropogenic inputs and more related to geogenic P enrichment.…”

“…Therefore, this region is also an ideal natural laboratory for studying the enrichment of geogenic P in groundwater systems. The P-contaminated groundwater typically resides in the shallow confined aquifer of the plain (at depths of 20–40 m). ,,, Notably, shallow groundwater not only interacts intensively with surface water but also has been a major source of water for human consumption and irrigation. , …”

“…The Jianghan (JH) and Dongting (DT) plains have high levels of geogenic P (≥4 mg/L) in aquifer systems. ,,, We have found that the dominant factor of groundwater P enrichment of the southern JH plain is OM and that of the western DT plain is FeOOH. ,, To comprehensively understand the underlying mechanisms of the observed geogenic P enrichment, we used a combination of direct sequential extraction and spectroscopic examination of sediments and an expanded set of laboratory extractions coupled with fluorescence spectrometry and mass spectrometry to (1) identify the characteristics of sediment OM types, FeOOH phases, and P pools and (2) reveal the coupled processes involving OM and FeOOH on geogenic P enrichment. Moreover, this study attempts to relate the microscopic genetic mechanism of geogenic P-rich groundwater to constraints of the regional scale geological setting.…”

Emerging investigator series: impacts of land use on dissolved organic matter quality in agricultural watersheds: a molecular perspective

“…33 Not only has this pipeline been shown to provide the accurate exact mass formula, but it has also been applied to other studies that condently identify P-containing DOM using exact mass. 34 Aer formula assignment, atomic ratios, aromaticity indices (AI mod ), 35 and the nominal oxygenation start of carbon (NOSC) 8,36 were all calculated and exported to R 37 for data visualization using the "ggplot2" package 38 and "corrplot" package for correlation plots and heatmap analyses. 39…”

“…54,55 Recent research has shown that a large fraction of P-containing DOM in groundwater is found in both the aliphatic and unsaturated DOM compound class and that these sources of P-containing DOM are intermediates to end products of organic matter biodegradation. 34,56,57 In addition, up to 40% of DOP species in stormwaters are found in low molecular weight, aromatic fractions below 1 kDa. 58 One possible explanation for the difference in DOP molecules can be linked to the type of agriculture.…”