| Zinc is not only essential element for plants and animals ,but also theheavy metal of environmental contamination. Most total Zinc of the soil mostexceed the quantity that plant need, but the availability of Zinc is lower insoil with high pH and calcareous . But in the soils of mineral zone near thecities , the content of zinc is so high that plants or crops are polluted. Sohow to improve the zinc availability for plant in zinc-absent soil and how toimmobilize the zinc in zinc-polluted soil are problems to which human being payattention. In this research, the incubation experiment in laboratory was usedfor studying the effect of seven kinds of materials (PAM, EDTA, citric acid,humic acid, zeolite, S and Carboxy methyl cellulose sodium) complexed with soilor zinc on the zinc fraction distribution, adsorption and desorption. The mainresults were showed as following: 1．Different materials including PAM,EDTA,citric acid and humic acidcompounded with soil or ZnSO4 showed that. with the application of ZnSO4, EDTAcould increase the availability of ZnSO4, all material could increase thequantity of Ca-Zn, Citric acid could increase the content of R2O3-Zn; that withoutzinc application, humic acide could increase the transformation of Zinc in soilto available zinc ,citric acid could evidently increase the quantity of EXC-Zn,PAM could evidently increase the quantity of Ca-Zn,that either with or withoutzinc application , EDTA could increase the quantity of EXC-Zn, humic acid coulddeduce the quantity of R2O3-Zn, all matierials especially EDTA,humic acid andcitric acid could evidently increase the quantity of OM-Zn, all materials haveno effects on the quantity of RES-Zn. 2．Different materials including PAM,EDTA,citric acid,humic acid,zeolite,S and CMCS compounded with ZnSO4 showed that PAM and EDTA could increase theavailability of ZnSO4,that EDTA,PAM and humic acid could increase the translationfrom ZnSO4 to EXC-Zn,that all material especially citric acid and S could decreasethe formation of Ca-Zn,that citric acid,humic acid,EDTA and S could increasethe quantity of R2O3-Zn, while CMCS could deduce,that humic acid and PAM couldincrease the translation from ZnSO4 to OM-Zn,that all materials have no evidenteffect on RES-Zn.⒊The soil complexded with different materials showed that all materialsexcept PAM could deduce zinc adsorption,of which EDTA is more evident ,that thecurve between adsorption amounts and adding zinc concentration fitted linearequation,that the curve between adsorption amounts and balance concentrationfitted Langmuir equation .All materials except PAM could increase the zincdesorption that has been adsorpted in soil, EDTA not only could evidentlyrestrain zinc adsorption in soil. but also could deduce zinc adsorptionintensily. ⒋Humic acid,CMCS and PAM complexed with zinc have no evident effect onadsorpting Zinc, while EDTA and citric acid could restrain Zinc adsorption. Thecurv between adsorption amouts and adding zinc concentration fits linearequation. The curve between adsorption and balance concentration fitsFreuncllich equation and langmuir(expcept for EDTA).Thrice Zinc desorption thathave been adsorpted showed that EDTA and citric acid could increase Zincdesorption that have been adsorpted while humic acid,CMCS and PAM could restrain.
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