الفهرس يوجد فقط 14 صفحة متاحة للعرض العام
 |  | from | 281 |  |  |
| | | from | 281 | | |
المستخلص
Onion is one of the oldest vegetable crops it has been cultivated for thousands of years for its religious significance medical properties and for its pungency and characteristic medical properties aged for its pungency and characteristic flavor it is considered one of the most important vegetable crops nutritional and medical values because of its contents of carbohydrates become 0110:- of the most environmental problems That facing man kind. To predict bioavailability, ud hence potential toxicity or deficiency, and ultimately the impact of heavy metals on plan’, animals lind humans. it iiiuperarive TO understand uieral-soil inraractions at II fimdamlllllal level. The deficiency 01’ roxiciry of heavy metal ill ecosystems depend nor only Oil thetotal metal eoncentration, bl1’ also more si!U)iiicil)ltly ou the soli, ability 10 sorb and release metal ions from eolid phase to replenish those removed from
olution by plant ’. Therefore, il is now gel1t$llly accepted 11Ial orprioude
icrption reactions ou the surface of beth inorganic and organic soil colloidal
meierials govern metal concentretions ill tile. soil solution. metals ;1) general and nickel as well a cobalt ill particular call beintroduced soil and water environmeurs from both uarural (as reactionproduct ~II IIIi’ digsol. miMrals) and aurhropogeuie (agricultural application of sewage sind e and fertilizers, and lor rnroegh land disposal of metal-contaminated municipal and industrial wastes) sources
(Wang and Xing. 2002; ”tIll’ et III., 200”). however. metals inputs in soil can rake several parhwa depending 011 the so’l abHilY to sorb-desorb or retain and store them accordin 10 rhe uarure behaviour of its constituents II well asrelative metals affinities for these surfaces to form strona complexes.
The maiu goal of this rudy was to evaluate the factors that llli~hl
control chemical behaviour of iand 0 ill soil. Fulfilling such a goal required throwing some Ii~JI1OD ’he effect of rhe domiaenr and effective soil eparare’ compoaeats OIl beth adsorpficn And I or precipitation of both , i 1I1ld Counder different concentration of these metals at different soil pH values.
Moreover. desorption of the previously adsorbed aud lor precipitated Ni and Co