Photoformation of persistent free radicals on a montmorillonite-humic acid complex simulated as particulate organic matter in an aqueous solution

As one of the frequently detected antibiotics in aqueous environment, the environmental behaviour of tetracycline has received increasing attention. Dissolved biochar (DBC) is an essential component of dissolved organic matter (DOM) in water enviroment. However, the effect of DBC on the photodegradation of tetracycline was unclear. This study investigated the impact of DBC on the photodegradation of tetracycline in aqueous solution under light illumination. The main components of DBC were humic acid-like and fulvic acid-like, accounting for 78.2% of the total components. The DBC surface had more oxygen-containing functional groups and aromatic functional groups. DBC increased the photodegradation of tetracyline by 46.9%, which was related to the component and structure of DBC. These findings would provid theoretical support for the environmental behaviour of DBC and tetracycline in aqueous environment.

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Relating particulate organic matter-nitrogen (POM-N) and non-POM-N with pulse crop residues, residue management and cereal N uptake

Agronomie ◽

10.1051/agro:2002056 ◽

2002 ◽

Vol 22 (7-8) ◽

pp. 777-787 ◽

Cited By ~ 8

Author(s):

Graeme D. Schwenke ◽

Warwick L. Felton ◽

David F. Herridge ◽

Dil F. Khan ◽

Mark B. Peoples

Keyword(s):

Organic Matter ◽

Particulate Organic Matter ◽

Crop Residues ◽

N Uptake ◽

Residue Management ◽

Pulse Crop

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Macrophyte-derived detritus in shallow coastal waters contributes to suspended particulate organic matter and increases growth rates of Mytilus edulis

Marine Ecology Progress Series ◽

10.3354/meps13314 ◽

2020 ◽

Vol 644 ◽

pp. 91-103

Author(s):

D Bearham ◽

MA Vanderklift ◽

RA Downie ◽

DP Thomson ◽

LA Clementson

Keyword(s):

Organic Matter ◽

Mytilus Edulis ◽

Particulate Organic Matter ◽

Coastal Waters ◽

Gill Tissue ◽

Suspension Feeder ◽

Food Sources ◽

Suspension Feeders ◽

Blue Mussels ◽

Suspended Particulate

Benthic suspension feeders, such as bivalves, potentially have several different food sources, including plankton and resuspended detritus of benthic origin. We hypothesised that suspension feeders are likely to feed on detritus if it is present. This inference would be further strengthened if there was a correlation between δ13C of suspension feeder tissue and δ13C of particulate organic matter (POM). Since detritus is characterised by high particulate organic matter (POC):chl a ratios, we would also predict a positive correlation between POM δ13C and POC:chl a. We hypothesised that increasing depth and greater distance from shore would produce a greater nutritional reliance by experimentally transplanted blue mussels Mytilus edulis on plankton rather than macrophyte-derived detritus. After deployments of 3 mo duration in 2 different years at depths from 3 to 40 m, M. edulis sizes were positively correlated with POM concentrations. POC:chl a ratios and δ13C of POM and M. edulis gill tissue decreased with increasing depth (and greater distance from shore). δ13C of POM was correlated with δ13C of M. edulis. Our results suggest that detritus comprised a large proportion of POM at shallow depths (<15 m), that M. edulis ingested and assimilated carbon in proportion to its availability in POM, and that growth of M. edulis was higher where detritus was present and POM concentrations were higher.

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Staining particulate organic matter with DTAF--a fluorescence dye for carbohydrates and protein:a new approach and application of a 2D image analysis system

Marine Ecology Progress Series ◽

10.3354/meps171077 ◽

1998 ◽

Vol 171 ◽

pp. 77-88

Author(s):

R Schumann ◽

D Rentsch

Keyword(s):

Image Analysis ◽

Organic Matter ◽

Particulate Organic Matter ◽

Image Analysis System ◽

New Approach ◽

Fluorescence Dye ◽

Analysis System

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Characterization of dissolved organic matter (DOM) extracted from soils by hot water percolation (HWP)

Agrokémia és Talajtan ◽

10.1556/agrokem.59.2010.1.12 ◽

2010 ◽

Vol 59 (1) ◽

pp. 99-108 ◽

Cited By ~ 3

Author(s):

M. Takács ◽

Gy. Füleky

Keyword(s):

Organic Matter ◽

Humic Acid ◽

Natural Organic Matter ◽

Extraction Methods ◽

Soil Samples ◽

Hot Water ◽

Soil Extracts ◽

Water Percolation ◽

Soil Humic Acid

The Hot Water Percolation (HWP) technique for preparing soil extracts has several advantages: it is easily carried out, fast, and several parameters can be measured from the same solution. The object of this study was to examine the possible use of HWP extracts for the characterization of soil organic matter. The HPLC-SEC chromatograms, UV-VIS and fluorescence properties of the HWP extracts were studied and the results were compared with those of the International Humic Substances Society (IHSS) Soil Humic Acid (HA), IHSS Soil Fulvic Acid (FA) and IHSS Suwannee Natural Organic Matter (NOM) standards as well as their HA counterparts isolated by traditional extraction methods from the original soil samples. The DOM of the HWP solution is probably a mixture of organic materials, which have some characteristics similar to the Soil FA fractions and NOM. The HWP extracted organic material can be studied and characterized using simple techniques, like UV-VIS and fluorescence spectroscopy.

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Characteristics of fouling due to clay-organic substances in potable water treatment by ultrafiltration

Water Science & Technology ◽

10.2166/wst.1996.0201 ◽

1996 ◽

Vol 34 (9) ◽

pp. 157-164 ◽

Cited By ~ 2

Author(s):

Kim C.-H. ◽

M. Hosomi ◽

A. Murakami ◽

M. Okada

Keyword(s):

Molecular Weight ◽

Organic Matter ◽

Humic Acid ◽

Fulvic Acid ◽

Size Distribution ◽

Ultrafiltration Membrane ◽

Organic Substances ◽

Decomposition Products ◽

Microbial Decomposition ◽

Fouling Materials

Effects of clay on fouling due to organic substances and clay were evaluated by model fouling materials and kaolin. Model fouling materials selected were protein, polysaccharide, fulvic acid, humic acid and algogenic matter (EOM:ectracellular organic matter, microbial decomposition products) and kaolin was selected as the clay material. Polysulfone membrane (MWCO(Molecular Weight Cut-Off) 10,000, 50,000 and 200,000) was used as an ultrafiltration membrane. In particular, the flux measurement of solutions containing algogenic matter used an ultrafiltration membrane of MWCO 50,000. The flux of protein and polysaccharide with coexistence of kaolin increased in the case of the ratio of MW/MWCO being greater than one, but did not increase in the case of the MW/MWCO ratio being below one. In contrast, the flux of fulvic acid and humic acid with coextence of kaolin decreased regardless of the ratio of MW/MWCO. The addition of dispersion agent and coagulant in the organic substances and kaolin mixture solution changed the size distribution of kaolin, and resulted in a change of the flux. EOM and microbial decomposition products decreased with the increase of the fraction of organic matter having molecular weight more than MWCO of membrane. The flux of the algogenic organic matter with coexistence of kaolin decreased with the increase of the amount of kaolin. It was suggested that the decline of the flux with coexistence of kaolin was due to the change of the resistance of the kaolin cake layer corresponding to the change in kaolin size distribution with charge.

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