Globally, about 1.5 billion people are infected with at least one species of soil-transmitted helminth (STH). Soil is a critical environmental reservoir of STH, yet there is no standard method for detecting STH eggs in soil. We developed a field method for enumerating STH eggs in soil and tested the method in Bangladesh and Kenya. The US Environmental Protection Agency (EPA) method for enumerat...

Soil respiration plays a significant role in the carbon cycle of Amazonian rainforests. Measurements of soil respiration have only been carried out in few places in the Amazon. This study investigated the effects of the method of ring insertion in the soil as well as of rainfall and spatial distribution on CO2 emission in the central Amazon region. The ring insertion effect increased the soil e...

Many municipalities have examined composting as an alternative to landfilling for the management of organic solid waste materials. Ultimately these materials will be land-applied and therefore some knowledge of nutrient availability will be necessary to optimize crop yield and minimize environmental risk. Field studies were conducted in 1993 and 1994 on a silt loam and a loamy sand soil in Wisc...

There is considerable concern about pollution of surface waters with P. Although most of the research has focused on inorganic P in surface runoff, it has recently become possible to easily follow the fate of soluble organic P forms in soils and waters. Two experiments were performed to compare the relative mobility and soil fixation affinity of orthophosphate monoesters, orthophosphate diester...

The effect of different tillage practices on soil hydraulic properties was studied in a mature, drip irrigated apricot orchard with a 7% slope, in Murcia (SE Spain). The soil had a loamy texture. Three soil tillage treatments were applied between the rows of trees: 1) control treatment (non-tilled, although weeds were cut to ground level using a blade attached to a tractor following the common ...

Biochar additions to degraded soils have the potential to improve crop yield and soil quality. We hypothesize that the biochar production process can be tailored to form designer biochars that have specific chemical characteristics matched to selective chemical and/or physical issues of a degraded soil. We produced biochars from peanut hulls, pecan shells, poultry litter, and switchgrass at tem...

The temperature sensitivity of enzymes responsible for organic matter decomposition in soil is crucial for predicting the effects of global warming on the carbon cycle and sequestration. We tested the hypothesis that differences in temperature sensitivity of enzyme kinetic parameters V max and K m will lead to a canceling effect: strong reduction of temperature response of catalytic reactions. ...

Column experiments were conducted with undisturbed loamy sand soil under unsaturated conditions (around 90% saturation degree) to investigate the retention of surfactant stabilized silver nanoparticles (AgNPs) with various input concentration (Co), flow velocity, and ionic strength (IS), and the remobilization of AgNPs by changing the cation type and IS. The mobility of AgNPs in soil was enhanc...