Chlorinated solvents in the subsurface are a widespread problem with thousands of impacted sites in the United States. A large body of literature exists that evaluates treatment of chlorinated solvents using granular zero valent iron, which has been shown to treat chlorinated solvents via reductive dechlorination. Much of this literature is conducted within the context of permeable reactive bar...

Sequential extraction is a useful method of identifying how toxic trace metals bind to soil particles and the strength of these bonds. This is very essential knowledge to reach an efficient soil washing when dealing with remediation of metal-contaminated soil. Sequential extraction uses a succession of extractions on a soil same sample, with extraction liquids expected to promote decreasing mob...

Organo-clay complexes in soil play an important role in the immobilization and persistence of xenobiotics. In this study, the fate of 14 C-labeled 4-(3,5-dimethylhept-3-yl)phenol (NP) and 4-chloro-2mehtylphenoxyacetic acid (MCPA) in soil was examined using incubation periods from 1d to 180d (NP) and 1d to 120d (MCPA). Special emphasis was on the distributions of the compounds and its degradatio...

Host suitability of commercial sunflower hybrids to Pratylenchus zeae was studied in the field and greenhouse. For comparison, one maize and one grain sorghum inbred line, both susceptible to P. zeae, were included in the greenhouse experiments. Pratylenchus zeae densities extracted from the roots of sunflower hybrids grown in naturally infested soil were low. In the first greenhouse experiment...

The importance of subsoil features for phosphorus (P) leaching is frequently mentioned, but subsoil effects are still poorly documented. This study examined whether the subsoil of four agricultural Swedish soils (two sand and two clay) functioned as a source or sink for P leaching by measuring P leaching from intact soil columns with topsoil (1.05 m deep) and without topsoil (0.77 m deep) over ...

-The adsorption of uncharged polymers by clays is largely "entropy-driven." Polymer conformation changes from a random coil in solution to an extended form at the surface in which adsorbed polymer segments or trains alternate with loops and tails extending away from the surface. Although the net interaction energy, e, per segment-surface contact is small (--1 kT unit), the total energy of adsor...

A first survey of entomopathogenic nematodes (EPN) was conducted in three agro-ecological zones of Southern Cameroon in 2007 and 2008. Entomopathogenic nematodes were recovered from 26 of 251 soil samples (10.4%). Three species, Heterorhabditis baujardi, Steinernema sp. A and Steinernema sp. B were found. The two steinernematids were considered unidentified species. Among the positive samples, ...

Soil susceptibility to seal formation and erosion depends on its inherent properties and surface conditions. Our objective was to study the interaction of two different surface conditions, antecedent moisture content (AMC) and aging duration, on seal formation and erosion in four smectitic soils. Soil samples were packed in trays and wetted with different amounts of water (0, 1, 2, 3, 4, 6, 8, ...