Relationship of Soil Organic Matter Characteristics to Organic Contaminant Sequestration and Bioavailability

Abstract

Sorption and desorption equilibria of phenanthrene with respect to three different types of geosorbents were measured, as were the rates of desorption and biological mineralization of this representative hydrophobic organic contaminant. The chemical nature of the organic matter associated with each geosorbent was characterized using solid state 13C‐NMR spectrometry. The results of these studies reveal that both the desorption behavior and the microbial bioavailability of the sorbed contaminant are influenced by the physicochemical character of the organic matter. The more reduced and condensed the organic matter, the greater the extent of sorption‐desorption hysteresis, the slower the desorption rate, and the less readily bioavailable the sorbed contaminant. These observations are consistent with projections predicated on a dual reactive domain model introduced earlier to describe the sorptive reactivities of different types of soil/sediment organic matter with hydrophobic organic contaminants.

Effects of sediment organic matter quality on bioaccumulation, degradation, and distribution of pyrene in two macrofaunal species and their surrounding sediment

“…Contaminants generally associa te stronger with refractory organic matter (Xing, 1997, Lueking, Huang, Soderstrom-Schwarz, Kim & Weber, 2000, Lyytikäinen, Hirva, Minkkinen, Hämäläinen, Rantalainen, Mikkelson et al, 2003. Enhanced retention of pyrene metabolites in lignin enriched sediment may thus give the impression of higher apparent pyrene biodegradation.…”

Relative importance of macrofaunal burrows for the microbial mineralization of pyrene in marine sediments: impact of macrofaunal species and organic matter quality

“…Consequently, properties of sedimenting organic matter directly affect overall microbial metabolic activity, but may also indirectly affect microbes through changes in macrofaunal activity (Graf et al 1983, Christensen & Kanneworff 1985, 1986, Graf 1992, with anticipated consequences for the degradation of organic contaminants. Changes in sediment organic matter (SOM) quality may also influence microbial PAH degradation by affecting sedimentary oxygen conditions, and through altered bioavailability of sediment-associated contaminants (Xing 1997, Lueking et al 2000.…”

Compostagem Como Alternativa De Biorremediação De Áreas Contaminadas

“…A quantidade de matéria orgânica é a característica do solo que mais influencia a sorção dos HAPs, sendo que vários autores demonstraram relações lineares positivas entre o conteúdo de carbono orgânico do solo e a capacidade de sorção de HAPs (CARMICHAEL e PFAENDER, 1997;NAM et al, 1998;LUEKING et al, 2000). A compostagem pode ser utilizada para o tratamento do solo contaminado com HAPs, sendo o solo removido do local de origem e colocado na forma de pilhas, que permitam o controle da lixiviação e do escoamento superficial dos líquidos originados.…”