abstract in order to study the chemical behavior of nickel and cadmium in the presence of organic matter, an experiment with two different soils (4 and 30 percent caco3), two different texture (8 and 40 percent clay), two levels of nickel (0 and 100 mg.kg-1), two levels of cadmium (0 and 25 mg.kg-1) and organic matter in the form of sewage sludge in two levels (0 and 100 t. ha-1), at three time...

this research was conducted at the department of horticluture, university of tehran during years 2005-2006, to investigate the use of iran apatite rocks in zeoponic substrate and as well to evaluate them as substitutes for phosphate fertilizers. five different substrates namely: m1: 89 wt. % soil+10 wt. % zeolite + 1 wt.% jeyrood apatite; m2: 82 wt.% soil + 15 wt.% zeolite+ 3 wt. % jeyrood apat...

Phosphorus concentration in the soil solution of agricultural soils should be a consensus of the agronomic and environmental aspect. Data from literary sources are inconsistent if the method of soil solution extraction from the soil and the method of phosphorus detection are not indicated. In the present paper a simplified procedure of soil solution extraction is used that is derived from the n...

The organic matter in the sea is unevenly distributed between the living plant and animal population, the suspended detritus, the organic matter in the sea bottom, and that present in the water in true and in colloidal solution. The living forms and the detritus make up only a small part of the total organic matter in the sea; the ratio between the organic matter in solution and that present in...

Accurate descriptions of P leaching are important because excess P applied to soils can enter surface water via leaching and subsurface transport, thereby negatively impacting water quality. The objectives of this study were to monitor P leaching in soils with a long-term history of waste application, relate soil solution P concentrations to soil P status, and quantify P leaching losses. Soil s...

BACKGROUND AND OBJECTIVES: This study aims down to evaluate the ability of chloride magnesium- aluminium- layered double hydroxides (4:1) for nitrate adsorption from the soil solution in successive cropping periods. METHODS: The study was conductedunder long-term cropping periods, including first crop): bell pepper; second crop: mentheae; third crop: cher...

Root activity can modify the chemistry of the rhizosphere and alter phosphorus (P) availability and uptake. However, until recently, relatively little was known about the dynamics of soil solution P at the root surface because of our inability to measure in situ changes in solution P at the plant root. A mini-rhizotron experiment with corn (Zea mays L. cv. Stine 2250), soybean [Glycine max (L.)...