Inorganic arsenicals have been used in agriculture as pesticides or defoliants for many years and, in localized areas, oxides of arsenic have contaminated soils as a result of fallout from ore-smelting operations and coal-fired power plants. Use of inorganic arsenicals is no longer permitted in most agricultural operations, and recent air pollution controls have markedly reduced contamination f...

carbonates are among the most common soil constituents in arid and semiarid zones. they exhibit many significant differences in their chemical and mineralogical, suite, origin, physical and micromorphological properties and consequently in their activities in soil. the differences cause different properties of calcareous soils. six profiles of aridisols and inceptisols with carbonate accumulati...

a r t i c l e i n f o Lamellae are thin, often discontinuous layers of clay-enriched material that are associated with iron oxides and may occur in Alfisols, Ultisols, Mollisols, Entisols, Inceptisols, or Spodosols. Our analysis of the SSURGO database revealed that there are 118 soil series with lamellae that represent six orders, 14 suborders, and 25 great groups, and 25 subgroups. In Soil Tax...

Clay minerals have been used in medicinal applications since Aboriginal times (Carretaro, 2002; Wilson, 2003). Clay poultices are used to heal wounds; people eat clays to coat stomach linings and soothe indigestion; animals eat clay containing trace elements (e.g., As) that can kill worms. The reasons that various clay minerals are effective as medicines may be as variable as the ailment, but b...

Both Fe(III)-bearing clay minerals and humic acids (HAs) are abundant in the soils and sediments. Previous studies have shown that bioreduction of structural Fe(III) in clay minerals could be accelerated by adding anthraquinone compound as a redox-active surrogate of HAs. However, a quinoid analogue could not reflect the adsorption and complexation properties of HA, and little is known about th...

We aimed to assess the presence and availability of arsenic (As) in intertidal marshes of the Scheldt estuary. Arsenic content was determined in soils sampled at 4 sampling depths in 11 marshes, together with other physicochemical characteristics. Subsequently, a greenhouse experiment was set up in which pore water arsenic (As) concentrations were measured 4 times in a 298-day period in 4 marsh...

An incubation experiment lasting 111 d was carried out to study the effect of the addition of three clay minerals (Nabentonite, Ca-bentonite, and zeolite) to soil derived from sewage sludge on water-extractable and exchangeable forms of four heavy metals (Zn, Cd, Cu, and Ni), as well as on soil organic matter mineralization, microbial biomass C and the release of inorganic N. The addition of cl...

The desirable physical and physiochemical properties of clay minerals have led them to play a substantial role in pharmaceutical formulations. Clay minerals like kaolin, smectite and palygorskite-sepiolite are among the world's most valuable industrial minerals and of considerable importance. The elemental features of clay minerals which caused them to be used in pharmaceutical formulations are...