Article

Effect of organic fertilizers derived dissolved organic matter on pesticide sorption and leaching

Department of Plant, Soil and Insect Sciences, University of Massachusetts Amherst, Amherst Center, Massachusetts, United States
Environmental Pollution (Impact Factor: 4.14). 04/2005; 134(2):187-94. DOI: 10.1016/j.envpol.2004.08.011
Source: PubMed

ABSTRACT

Incorporation of organic fertilizers/amendments has been, and continues to be, a popular strategy for golf course turfgrass management. Dissolved organic matter (DOM) derived from these organic materials may, however, facilitate organic chemical movement through soils. A batch equilibrium technique was used to evaluate the effects of organic fertilizer-derived DOM on sorption of three organic chemicals (2,4-D, naphthalene and chlorpyrifos) in USGA (United States Golf Association) sand, a mixed soil (70% USGA sand and 30% native soil) and a silt loam soil (Typic Fragiochrept). DOM was extracted from two commercial organic fertilizers. Column leaching experiments were also performed using USGA sand. Sorption experiments showed that sorption capacity was significantly reduced with increasing DOM concentration in solution for all three chemicals. Column experimental results were consistent with batch equilibrium data. These results suggest that organic fertilizer-derived DOM might lead to enhanced transport of applied chemicals in turf soils.

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    • "K F values for adsorption ranged from 5.32 to 15.78 for chlorpyrifos and from 3.93 to 6.54 for TCP. Similar observations have been reported in studies involving chlorpyrifos soprtion in soils (El-Nahhal, 2002; Li et al., 2005). The results showed that chlorpyrifos bound more strongly to soils than its metabolite TCP. "
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    • "This non-catalytic detoxification would help to overcome the potential side effects from other common remediation systems. For example, Li et al. (2005) showed that the addition of commercial organic amendments (32e35% organic carbon) to soil led to an increase of dissolved organic matter and, subsequently , a higher chlorpyrifos mobility. As current data show, the irreversible binding between CbE and chlorpyrifos-oxon would reduce its transport and toxicity, despite the inhibitoreenzyme complex might also be mobilized with the dissolved organic matter as well. "
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    • "Dissolved organic carbon (DOC) plays a great role in terrestrial and aquatic ecosystems (Jones et al. 2004; Monaghan et al. 2007; Haaland and Mulder 2010). DOC may enhance the sorption and mobility of pesticides and heavy metal in surface waters and leads to drinking water quality problems (David et al. 1991; Li and Shuman 1997; Li et al. 2005). Loss of DOC from agricultural soil occurs at the expense of both soil organic carbon and water quality. "
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