Fulvic acids dissolved organic matter

Aldrich humic acid humic acid from soil water samples fulvic acid dissolved organic matter samples, Jota Hassett 1991)... 

Recently, Burkhard (2000) reviewed contaminant sorption by dissolved organic matter. Using several hundreds of UCC-water partition coefficients (A doc) reported in these studies, he found that UCC-water partition coefficients for naturally occurring DOC (humic and fulvic acids, sediment pore water, soil pore water, groundwater, and surface water) was best described by... 

In environmental situations, dissolved organic matter such as fulvic acids frequently increase the apparent solubility. This is the result of sorption of the chemical to organic matter which is sufficiently low in molecular mass to be retained permanently in solution. The "true" solubility or concentration in the pure aqueous phase probably is not increased. The apparent solubility is the sum of the "true" or dissolved concentration and the quantity which is sorbed. 

Sensitized photolysis mainly involves the photochemistry of dissolved organic matter (DOM), consisting of water-dissolved organic compounds that usually derive from the microbiological transformation of animal and plant spoils. A very important role is played in this context by humic and fulvic acids and in particular by their aromatic/quinonoid moieties, which mainly arise from the biodegradation of lignin and are considerably photoactive [8],... 

The importance of the interaction of organic compounds with calcium carbonate surfaces has long been recognized. It has been demonstrated that aragonite precipitation is inhibited by uncharacterized dissolved organic matter (Chave and Suess, 1967), and that humic and fulvic acids, and certain aromatic carboxylic acids, inhibit seeded aragonite precipitation from seawater (Berner et al., 1978). The selective adsorption of amino acids on carbonate substrates has received considerable attention. A preferential adsorption of aspartic acid has been shown from humic and fulvic acids and proteinaceous matter (Carter and Mitterer, 1978 Carter, 1978 Mitterer, 1971). 

Humic substances represent a large fraction of what is termed chromophoric dissolved organic matter (CDOM) in aquatic systems around the world. Aquatic humic substances can be further categorized as fulvic acids, humic acids, and humin based on theis solubility in acid and base solutions. 

Cabaniss S. E. and Shuman M. S. (1988a) Copper binding by dissolved organic matter I. Suwannee River fulvic acid equilibria. Geochim. Cosmochim. Acta 52, 185-193. 

Dissolved organic matter, expressed as chemical oxygen demand (COD) or total organic carbon (TOC), including methane, volatile fatty acids (in particular in the acid phase of the waste stabilization Christensen and Kjeldsen (1989), and more refractory compounds, e.g., fulvic-like and humic-like compounds. 

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