make better predictions about the mobility of contaminants, it is critical that time-dependent metal sorption To improve predictions of the toxicity and threat from Pb contamiand desorption behavior on soil be understood, as well nated soil, it is critical that time-dependent sorption and desorption behavior be understood. In this paper, the sorption and desorption as the mechanism of the sorpt...

Nitroaromatic compounds (NACs) are commonly found as soil contaminants in military training sites and manufacturing facilities, and may adversely affect human and ecosystem health. Exchangeable cation effects on p-nitrocyanobenzene (p-NCB) and 1,4-dinitrobenzene (1,4-DNB) sorption by the Webster (fine loamy, mixed, mesic Typic Haplaquoll) soil series A (WA) andB (WB) horizons were determined fr...

Batch sorption of sulfamethazine was conducted using five soils with organic carbon (OC) contents ranging from 0.1% to 3.8% and solution pHs ranging from 5.5 to 9. Sorption of sulfamethazine was found to be impacted by OC, soil surface area and soil solution pH, with higher K(d) values for soils with higher OC and lower K(d) values as the pH increased. However, OC was found to be the more domin...

This study investigates time-dependent sorption of pesticides in soil aggregates. We tested if the sorption kinetics of pesticides in soil aggregates can be described by modeling diffusion into aggregates for a range of soils and pesticides. Our hypothesis is that the rate of sorption is negatively related to sorption strength due to retardated diffusion. Natural aggregates of 3-5 mm diameter w...

Sorption and degradation are the primary processes controlling the efficacy and runoff contamination risk of agrochemicals. Considering the longevity of biochar in agroecosystems, biochar soil amendment must be carefully evaluated on the basis of the target agrochemical and soil types to achieve agricultural (minimum impact on efficacy) and environmental (minimum runoff contamination) benefits....

Previously published research used an isotope-exchange technique to measure irreversibility of pesticide sorption-desorption in soil. Results indicated significant irreversibility (6-51%) in sorption in five pesticide-soil systems measured over 72 h. Here, we propose a three-site model to reanalyze the experimental data. The model adds a slow but reversible binding on nonequilibrium sorption si...

Several recent studies have shown that n-octanol/water partition coefficients may not be a good predictor for estimating soil sorption coefficients of persistent organic pollutants (POPs), defined here as chemicals with log Kow greater than 5. Thus, an alternative QSAR model was developed that seems to provide reliable estimates for the soil sorption coefficients of persistent organic pollutant...

Soil aggregates were prepared from a bulk soil collected from paddy soil in the Taihu Lake region and aluminum (Al) dissolution, solution pH changes during copper (Cu(2+)) sorption were investigated with static sorption and magnetic stirring. Kinetics of Cu(2+) sorption and Al dissolution were also studied by magnetic stirring method. No Al dissolution was observed until Cu(2+) sorption was gre...

Sorption-desorption interactions of pesticides with soil determine the availability of pesticides in soil for transport, plant uptake and microbial degradation. These interactions are affected by the physical and chemical properties of the pesticide and soil and, for some pesticides, their residence time in the soil. While sorption-desorption of many herbicides has been characterised, very litt...

Agricultural and soil management practices have been reported to affect alachlor sorption–desorption and degradation rates. Though alachlor has been banned in the E.U. since 2006, it is still used in U.S. corn and soybean production. The objectives of this study were to: (a) assess differences in alachlor sorption due to tillage treatments (chisel plow and ridge tillage) on soils from three mid...