Biogeochemical transformation (inclusive of dissolution) of iron (hydr)oxides resulting from dissimilatory reduction has a pronounced impact on the fate and transport of nutrients and contaminants in subsurface environments. Despite the reactivity noted for pristine (unreacted) minerals, iron (hydr)oxides within native environments will likely have a different reactivity owing in part to change...

The availability of iron within the surface waters of the broad, oligotrophic West Florida Shelf (WFS) controls periodic blooms of the pelagic marine cyanobacterium Trichodesmium. Summer delivery of Saharan dust provided adequate iron (Fe) to shift limitation of growth to the availability of phosphorus (P). Florida’s rivers drain Miocene phosphorus deposits to provide the WFS with freshwater nu...

Reject water, which is the liquid fraction produced after dewatering of anaerobically digested activated sludge on the municipal wastewater treatment plants (MWWTPs), contributes up to 80% of the nitrogen and phosphorus loads to the MWWTP. It was proposed to combine the removal of nitrogen from reject water using the sequential biooxidation of NH(4)(+) and bioreduction of NO(3)(-) with precipit...

BACKGROUND Iron (Fe) deficiency anemia remains the largest nutritional deficiency disorder worldwide. How the gut acquires iron from nano Fe(III), especially at the apical surface, is incompletely understood. OBJECTIVE We developed a novel Fe supplement consisting of nanoparticulate tartrate-modified Fe(III) poly oxo-hydroxide [here termed nano Fe(III)], which mimics the Fe oxide core of ferr...

Although the presence of an exogenous anion is a requirement for tight Fe(3+) binding by the bacterial (Neisseria) transferrin nFbp, the identity of the exogenous anion is not specific in vitro. nFbp was reconstituted as a stable iron containing protein by using a number of different exogenous anions [arsenate, citrate, nitrilotriacetate, pyrophosphate, and oxalate (symbolized by X)] in additio...

This study was conducted to determine phosphorus (P) species captured in a vertical-flow constructed wetland (VFCW) system combining a trickling filter followed by FeCl3 injection for phosphate coagulation. Suspended solids (SS) thus formed accumulated over time at the VFCW surface and transformed into a sludge deposit layer, which was shown to concentrate most of the P captured in the system. ...

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...

knowledge of the phosphorus (p) forms is essential for understanding the behavior of phosphorus. the aim of this study was to investigate the effect of wheat cultivation on different inorganic p forms of soil. a greenhouse factorial experiment in a completely randomized design was carried out with three replications in 20 soil types and plantation at two levels (with and without plantation). th...

Previous studies suggested an increase in the proportion of calcium phosphates (CaP) of the total phosphorus (P) pool in soils with a long-term poultry manure application history versus those with no or limited application histories. To understand and predict long-term P accumulation and release dynamics in these highly amended soils, it is important to understand what specific P species are be...

Iron (Fe) oxyhydroxide colloids facilitate the transport of organic matter, oxyanions and trace metals in environment. This study was set up to compare sizes Fe-organic carbon (OC) formed by oxidation Fe(II) presence different concentrations Suwannee River Natural Organic Matter (NOM) evaluate how variable dissolved (DOC) Fe ratios impact binding phosphate. The molar DOC/Fe ratio test solutions...