Transgenic glyphosate-resistant (GR) soybean [Glycine max (L.) Merr.] has enabled highly effective and economical weed control. The concomitant increased application of glyphosate could lead to shifts in the soil microbial community. The objective of these experiments was to evaluate the effects of glyphosate on soil microbial community structure, function and activity. Field assessments on soi...

Long-term application of poultry (Gallus gallus domesticus) litter has built high levels of P in certain Coastal Plain soils of north Louisiana. However, soil P/runoff P relationships for soil and environmental conditions of the area have not been examined. This study measured soil P (total, Bray 1, Bray 2, Mehlich 3, resin-exchangeable, and water-extractable) and runoff P (dissolved P, DP; and...

Repeated application of diazinon granules to the soil Surface of rice fields affected the development of a biological factor that caused rapid degradation of diazinon. This factor was present in the paddy water, in rhizosphere soil of the rice plant, and in nonrhizosphere soils. Isotope studies showed that when incubated with water from diazinon-treated fields, diazinon was hydrolyzed to 2-isop...

an experiment involving erosion simulation was conducted at the soil and water con-servation research center of the university of tehran. a split-factorial plot with four replications was designed. five soil desurfacing treatments of blank, 5, 10, 15, and 20 cm of soil surface removal (e0, e5, e10, e15, and e20) were carried out, respectively. fertilizer treatments were 0, 65, and 130 kg ha-1 o...

Surface-applied chemicals move through the unsaturated zone with complex flow and transport processes due to soil heterogeneity and reach the saturated zone, resulting in groundwater contamination. Such complex processes need to be studied by advanced measurement and modeling techniques to protect soil and water resources from contamination. In this study, the interactive effects of factors lik...

The time between swine (Sus scrofa) manure application to soil as a crop fertilizer, the first rainfall event, and the frequency of rainfall events should influence leaching potential of fecal pathogens. Soil microcosms were inoculated in the lab with a swine manure isolate of Escherichia coli, strain RS2G, expressing green fluorescent protein, to examine how timing and frequency of rainfall ev...

The application of compost or fertilizer at rates that exceed crop nutrient requirements can result in phosphorus (P) and nitrogen (N) accumulation in soil. This study was conducted to determine the influence of soil P and N contents on the concentrations and total amounts of P and N transported in runoff. Composted beef cattle feedlot manure or inorganic fertilizer were added from 1992 to 1995...

Soil fumigation is commonly used to control soil-borne pathogens and weeds. Our aim was to examine the effects of soil fumigation with chloropicrin (CP) and methyl isothiocyanate (MITC) on CH4, N2O and CO2 production and emission. These effects on a SE USA forest nursery soil were examined in field and laboratory experiments. Following field fumigation, CH4 surface emissions and concentrations ...

A GIS method for modeling landscapes to predict total soil depth and the depth of different soil layers is presented. The method is based on terrain analysis using a DEM and the combined use of the Topographic Wetness Index (TWI) also known as the Compound Topographic Index (CTI) and the Multi-resolution Valley Bottom Flatness index (MrVBF). Examples of the output for several catchments show th...