Black spruce (Picea mariana) forests represent the dominant vegetation type throughout the North American and Siberian taiga and are generally considered ro be pristine, N-limiting environments. The aim of this sludy was to investigate the fundamental underlying mechanisms which control N availabil~ty in these soils with particuiar reference to the dynamics of dissolved organic nitrogen (DON) O...

Organic soils are an important source of N2O, but global estimates of these fluxes remain uncertain because measurements are sparse. We tested the hypothesis that N2O fluxes can be predicted from estimates of mineral nitrogen input, calculated from readily-available measurements of CO2 flux and soil C/N ratio. From studies of organic soils throughout the world, we compiled a data set of annual ...

the effect of 0, 2, and 5 mm of citric, malic and oxalic acids on phosphorus (p) sorption was evaluated. in the collected soils, the level of total calcium carbonate stood in the range of 4-28%, clay content at 33-56% and the amount of organic matter recorded within 0.6-2.7%. the results indicated that the addition of organic acids causes reduction in p sorption. citric acid in most soils, was ...

On a sequence of soils developed under similar vegetation, temperature and precipitation conditions, but with variations in mineralogical properties, we use organic carbon and C inventories to examine mineral protection of soil organic carbon. In these soils, C data indicates that the creation of slow-cycling carbon can be modeled as occurring through reaction of organic ligands with Al and Fe ...

In situ chemical oxidation is a commonly applied soil and groundwater remediation technology, but can have significant effects on soil properties, which in turn might affect fate and transport of organic contaminants. In this study, it was found that oxidation treatment resulted mainly in breakdown of soil organic matter (SOM) components. Sorption of naphthalene and phenanthrene to the original...

Certain organic C moieties of soil origin in drinking source waters of Sacramento-San Joaquin Delta (Delta) can react with chlorine to form trihalomethanes (THMs) during the disinfection process. Isolation and characterization of them and quantitation of their THM formation potential (THMFP) is necessary for developing effective strategies to reduce their influxes in Delta waters and for removi...

Filters with a pore size of 0.45 microm have been arbitrarily used for isolating dissolved organic carbon (DOC) in natural waters. This operationally defined DOC fraction often contains heterogeneous organic carbon compounds that may lead to inconsistent results when evaluating trihalomethane formation potential (THMFP). A finer pore size filter provides more homogeneous DOC properties and enab...

Soil sorption and dissipation of fluometuron (FLM) and three metabolites, desmethyl fluometuron (DMF), trifluoromethyl phenyl urea (TFMPU), and trifluoromethyl aniline (TFMA), were assessed in conservation tillage soils. In study I, surface Dundee silt loam soils from no-tillage (NT) and reduced-tillage (RT) areas were treated with 14C ring-labeled FLM or TFMA or unlabeled DMF, incubated for 34...

abstract the objectives of this research was to evaluate the rhizospheric effects of wheat (triticum aestivum l.) on the status of various inorganic p fractions and total organic p in 10 calcareous soils amended with 1% (w/w) municipal sewage sludge from the refinery of shahrekord city under rhizobox conditions. thus, wheat plant was planted in completely randomized design with three replicatio...

This study examined the concentration of organic and inorganic phosphorus in surface soils of a Bouteloua gracilis-Bouteloua eriopoda grassland, and a Larrea tridentata shrubland, in the northern Chihuahuan Desert, New Mexico, USA. In this desert where the grassland vegetation has a uniform spatial distribution and individual shrubs have a patchy spatial distribution across the landscape, veget...