Aquatic Humic Substances

Abstract

Introduction and Historical Outline Occurrence Hydrophobic and Hydrophilic Fractions Chemical Structure Elemental Composition Molecular Size Distribution and Charge Spectral Absorbance and Fluorescence Infrared Spectra Mass Spectrometry NMR Spectroscopy Soft Hydrolysis Interaction of Humic Matter with Other Water Constituents Fate of Humics in Technical Application of Water Viewing the Function in Aquatic Ecosystems

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“…On the other hand, together with decaying of primary producers, humic matter might contribute to the sediment organic carbon content, as a function of transportation through the coastal wave erosion at Sinop peninsula and autochtonously derived matter from biological activities. Because, C/N ratio is reported 76 for FA and 50 for HA in soil seepage (Frimmel, 2001) and HA with high C/N ratios (71.48-87.36) have been detected in the river bottom sediments by Rahman et al (2010). There was no significant difference between TOC values in Sinop and İğneada sediments but higher C/N ratio in the Sinop sediment ( Figure 5) could be attributed to preferential nitrogen depletion in N-rich labile compounds (like proteins) during early diagenesis of OM (Krishna et al, 2013).…”

“…C/N ratios were not very different but higher C/N ratio in Bartın surface sediment also indicated nitrogen depletion. High C/N ratios in Bartın, Bafra, Samsun and SB1 could be due to terrestrial sources which have been observed with C/N ratios: 17.5-12.1 (Prahl et al, 1994) and could be due to the contribution of the wastewaters (untreated municipal and industrial) which may also contain humic matter (with C/N:17;Frimmel, 2001). High organic matter has been reported (Bakan and Arıman, 2004) and TOC value was similar with this study around the same location in the Samsun Bay.…”

“…degradation of dead organic matter within the water body itself (autochthonous substances) (Frimmel, 2001). So, HS have different C/N ratios due to age and structural differences (hydrophilic-Fulvic acid: FA and hydrophobic-Humic acid: HA) in the original sample: Brown water: FA: 64, HA: 45; Soil seepage: FA: 76, HA: 50; Secondary effluent: FA: 17, HA: 7.4 (Frimmel, 2001).…”

“…Krishna et al (2013) were found the higher C/N ratios in the shelf (range: 9.9-46.6) and indicated that coastal regions receive huge amount of terrestrial OM, detritus of agricultural crops through river discharge from the nearby continents and contribute the sediment content. So, the excess carbon in the İğneada sediment could be related with deposition of degraded plants from forest (allocthonous or terrestrial source) and humic substances (Frimmel, 2001).…”

Enhanced Mobilization of Field Contaminated Soil-bound PAHs to the Aqueous Phase under Anaerobic Conditions

“…The ratio of spectroscopic absorptivities at wavelengths of 465 and 665 nm for DOM (E 4 /E 6 ratio) were employed for the general molecular composition, chemical structure, and diagenetic characteristics of DOM (Aiken et al 1985;Chen et al 1977). Specific ultra-violet absorbance (SUVA) values measured at wavelengths at 254 and 280 nm were also used for the aromatic property of DOM (Aiken et al 1985;Frimmel 2001). Relative size and weight of DOM were estimated using highpressure size exclusion chromatography (HPSEC) as described in a prior study (Zhou et al 2000).…”