Lead arsenate was used on orchard soils as a pesticide from 1900 to 1960. An in vitro method has been used to determine the bioaccessiblity of Pb in soils contaminated by Pb paint, fossil fuel combustion, and metallurgical industries. The Pb fraction that is potentially bioavailable from orchard soils, however, has not been reported. Potential reductions in availability of Pb and As as a result...

Urine excreted by cattle can produce very high concentrations of available N in relatively small volumes of soil and lead to high nitrous oxide (N2O) emissions. Application of the nitrification inhibitor dicyandiamide (DCD) can inhibit nitrification. DCD application results in lower nitrate (NO3 ) concentrations and N2O emissions from denitrification in urine affected soils. However, the effect...

When woody plant abundance increases in grasslands and savannas, a phenomenon widely observed worldwide, there is considerable uncertainty as to whether aboveground net primary productivity (ANPP) and ecosystem carbon (C) and nitrogen (N) pools increase, decrease, or remain the same. We estimated ANPP and C and N pools in aboveground vegetation and surface soils on shallow clay and clay loam so...

The poor mobility of organic pollutants in contaminated sites frequently results in slow remediation processes. Organics, especially hydrophobic compounds, are generally retained strongly in soil matrix as a result of sorption, sequestration, or even formation into non-aqueous-phase liquids and their mobility is thus greatly reduced. The objective of this study was to evaluate the feasibility o...

The soybean cyst nematode (SCN), Heterodera glycines Ichinohe, is a severe pest of soybean, Glycine max (L.) Merr., in the United States. Nematode reproduction and the seed yield losses caused by this nematode are influenced by soil texture (3,5,6). Todd and Pearson (5) recovered higher numbers of SCN females and cysts from a sandy loam soil than from silty loams. Soybean yield also has been ne...

Solid phase microextraction (SPME) coupled with gas chromatography was employed to estimate bioavailability of pyrene in soils with different properties of textures, organic matter contents (SOM) and aging periods. Experimental results indicated that biodegradation rates increased from 0.10 (sandy loam) to 0.15 (silty loam) microg g-1 hr1. By contrast, biodegradation rate decreased from 0.10(1....

Poultry litter applications to land have been based on crop N requirements, resulting in application of P in excess of plant requirements, which may cause degradation of water quality in the Chesapeake Bay watershed. The effect of litter source (the Delmarva Peninsula and Moorefield, West Virginia) and composting of poultry litter on N mineralization and availability of P in two soil types (san...

Little is known about the contribution made by the egg stage of African malaria vectors to the rapid rise in adult populations following the onset of seasonal rains. To examine this issue, we evaluated the viability of Anopheles gambiae eggs in drying soil in the laboratory. Survival data were collected from field-caught mosquitoes kept in sandy loam soil and laboratory-reared colonies kept in ...