in a greenhouse experiment, changes in inorganic phosphorus fractions as well as their availability in the rhizosphere of rice (oryza sativa c.v. khazar) crop, following an application of 40 mg p (as monocalcium phosphate per kg of soil) were investigated in paddy soils north of iran. the study was performed as a 14×2 factorial in a completely randomized design of two factors namely: soil at 14...

abstract uranium as a natural radioactive heavy metal widely disperses throughout the earth's crust. in many cases, the natural abundance has been re-distributed due to anthropogenic activities, resulting in radionuclide contamination in groundwater and surface soil. uranium through the plant uptake can enter the chain. the degree of speciation of radio nuclides in soils in areas with differing...

this study was carried out to obtain quantitative relationships between zn in equilibrium solution and that retained by 20 calcareous soils. soils were brought into equilibrium with varying solution concentrations of zn, and the amounts removed from solution were used to check the fit to six adsorption isotherms, namely, freundlich, langmuir, temkin, gunary, two surface langmuir and adjusted fr...

Carbon-rich biochar derived from the pyrolysis of biomass can sequester atmospheric CO, mitigate climate change, and potentially increase crop productivity. However, research is needed to confirm the suitability and sustainability of biochar application to different soils. To an irrigated calcareous soil, we applied stockpiled dairy manure (42 Mg ha dry wt) and hardwood-derived biochar (22.4 Mg...

this study was conducted to determine soil properties that correlate with the arbuscular mycorrhizal fungal (amf) spore numbers in semiarid calcareous soils of hamadan province in northwestern of iran. soil samples from six sites managed differently were collected from a 0 to 30 cm depth. the results showed that land use and management systems had a significant effect on amf spore number in soi...

Phytoremediation appears to be a promising technique for metal soil clean up, although its successful application on a large scale still remains a challenge. Field experiments for six scented Pelargonium cultivars, conducted on two Pb-contaminated calcareous and acidic soils, revealed vigorous plant growth, with no symptoms of morpho-phytotoxicity in spite of high Pb accumulation levels. Lead c...

A study was initiated to investigate the relationship between soil test P and depth of soil sampling with runoff losses of dissolved molybdate reactive phosphorus (DMRP). Rainfall simulations were conducted on two noncalcareous soils, a Windthorst sandy loam (fine, mixed, thermic Udic Paleustalf) and a Blanket clay loam (fine, mixed, thermic Pachic Argiustoll), and two calcareous soils, a Purve...

Adsorption and precipitation reactions often dictate the availability of phosphorus in soil environments. Tripolyphosphate (TPP) is considered a form of slow release P fertilizer in P limited soils, however, investigations of the chemical fate of TPP in soils are limited. It has been proposed that TPP rapidly hydrolyzes in the soil solution before adsorbing or precipitating with soil surfaces, ...

Gravely calcareous soils cover approximately most of arid lands (in percent); however, the solute transport behavior in these soils remains a current issue. This research aimed at estimating and correlating the solute transport parameters in gravely calcareous soils as being affected by different land uses through the knowledge of the soil morphological, physical, and chemical properties. Four ...