Allah Dadi, I. (2002). Investigating the Effect of Super-Adsorption Hydrogel on Drought Stress in Plants. Proceedings of the Second Specialized Training Course on Agricultural and Industrial Application of Super Absorbent Hydrogels, Iran Polymer and Petrochemical Research Institute (In Farsi).
Allison, L. E. and Moodie, C. D. (1965). Carbonate, Black Methods of soil analyses. P 1379-1396.
Alloway, B. J. (1995). Heavy Metals in Soils (2nd Ed.). Blackie Academic and Professional, Glasgow, UK.
Andreu, V. and Gimeno-Garcia, E. (1996). Total content and extractable factions of cadmium, cobalt, nickel, lead and zinc in calcareous soils. Communication in Soil Science and Plant Analysis, 27, 2633-2648.
Baker, A. J. M., Reeves, R. D. and Hajar, A. S. M (1994). Heavy metal accumulation and tolerance in British populations of the metallophyte Thlaspi caerulescens J. and C. Presl (Brassicaceae). New Phytologist, 127(1), 61-68.
Bouyoucos, C. J. (1962). Hydrometer method improved for making particle-size analysis of soil. Agronomy Journal, 54(5), 464-465.
Bucheli-Witschel, M. and Egli, T. (2001). Environmental fate and microbial degradation of aminopolycarboxylic acids. FEMS Microbiology Reviews, 25(1), 69-106.
Chen, C., Huang, D., and Liu, J. 2009. Functions and toxicity of nickel in plants: recent advances and future prospects. Clean-soil, air, water. 37: 4-5. 304-313.
Cheng, G. L., Ma, X. F., Sun, X. B., and Zhao, S. Q. 2012. Effects of EDTA, EDDS and Citric Acid on Growth of Maize and Uptake of Lead by Maize in Contaminated Soil. In Advanced Materials Research, 534: 277-280.
Escande, V., Garoux, L., Grison, C., Thillier, Y., Debart, F., Vasseur, J. and Grison, C. (2014). Ecological catalysis and pHytoextraction: symbiosis for future. Applied Catalysis B: Environmental, 146, 279-288.
Fine, p., Paresh, R., Beriozkin, A. and Hass, A. (2014). Chelant-enhanced heavy metal uptake by eucalyptus trees under controlled deficit irrigation. Science of the Total Environment, 493, 995-1005.
Ghasemi, SH. (2012). Preparation of Distribution Map of Pb, Cadmium and Nickel Metals in Agricultural Lands of South of Tehran Using Ground and GIS. Master's thesis, Faculty of Agriculture and Natural Resources, Shahed University. (In Farsi)
Gonz´alez, I., Neaman, A., Cortes, A. and Rubio, P. (2014). Effect of compost and biodegradable chelate addition on pHytoextraction of copper by Oenothera picensis grown in Cu-contaminated acid soils. Chemosphere, 95, 111–115.
Goyer, R. A. (1991). Toxic effects of metals, in, Casarett and Doull's Toxicology, New York, P 623-680.
Helalia, A., and J. Letey. 1988; Cationic polymer effects on infiltration rates with a rainfall simulator. Soil Science Society of America Journal 52: 247-250
Hsiao, K. H., Kao, P. H. and Hseu, Z. Y. (2007). Effects of chelators on chromium and nickel uptake by Brassica juncea on serpentine-mine tailings for phytoextraction.Journal of Hazardous Materials,148(1-2): 366-376.
Huang, J. W., Blaylock, M. J., Kapulnik, Y. and Ensley, B. D. (1998). Phytoremediation of uranium-contaminated soils: role of organic acids in triggering uranium hyperaccumulation in plants. Environmental Science and Technology, 32(13), 2004-2008.
Karimi, A. (1993). Investigating the Effect of Igeta Correction on Some Physical Properties of Soil and Plant Growth. MSc thesis, University of Tehran, Iran (In Persian).
Kalra, Y. P. 1998 Handbook of reference methods for plant analysis Boca Raton, CRC Press.
Ker, K., and Charest, C. 2010. Nickel remediation by AM-colonized sunflower. Mycorrhiza, 20: 399-406.
Komarek, M., Tlustos, P., Szakova, J., Chrastny, V. and Ettler, V. (2007). The use of maize and poplar in chelant- enhanced phytoextraction of lead from contaminated agricultural soils. Chemosphere, 67(4), 640-651.
Lan, J., Zhang, S., Lin, H., Li, T., Xu, X., Li, Y. and Gong, G. (2013). Efficiency of biodegradable EDDS, NTA and APAM on enhancing the phytoextraction of cadmium by Siegesbeckia orientalis L. grown in Cd-contaminated soils. Chemosphere, 91(9), 1362-1367.
Lee, J. H., Hossner, L. R., Attrep, J. M. and Kung, K. S. (2002). Comparative uptake of plutonium from soils by Brassica juncea and Helianthus annuus. Environmental Pollution, 120(2), 173-182.
Lindsay, W. L. and Norvell, W. A. (1978). Development of a DTPA soil test for zinc, iron, manganese and copper. Journal of Soil Science Society America, 42(3), 421-428.
Litvinovich, A. V. and Pavlova, O. Y. (1995). Cultivation of cotton in zone affected by industry. Agrochimia, 12, 105-110.
Liu, D., Islam, E., Li, T., Yang, X., Jin, X. and Mahmood, Q. (2008). Comparison of synthetic chelators and low molecular weight organic acids in enhancing phytoextraction of heavy metals by two ecotypes of Sedum alfredii Hance. Journal of Hazardous Materials, 153(1-2), 114-122.
Lotfy, S. M., Zhran, M. A., and Abdel‐Sabour, M. (2014). Influence of Some Chelators on the Phytoextraction Ability of Sunflower (Helianthus annuus) for Nickel‐Contaminated Soil. Remediation Journal, 25(1), 101-114.
Matraszek, R., Hawrylak-Nowak, B., Chwil, S., and Chwil, M. 2016. Macronutrient composition of nickel-treated wheat under different sulfur concentrations in the nutrient solution. Environ. Science. Pollut. Res. 23: 6. 5902-5914.
Meers, E., Ruttens, A., Hopgood, M. J., Samson, D. and Tack, F. M. G. (2005). Comparison of EDTA and EDDS as potential soil amendments for enhanced phytoextraction of heavy metals, Chemosphere, 58(8), 1011-1022.
Metanat Jahromi, K. (2013). The effect of organic acids on the phytoremediation of lead and nickel by Corn, Master's thesis, University of Shiraz, Iran (In Farsi).
Mohammadpour, G., Karbassi, A., and Baghvand, A. 2016. Pollution intensity of nickel in agricultural soil of Hamedan region. CJES. 14: 15-24.
Moral, R., Robert, J. G. and Caselles, J. M. (2002). A comparison of extractants for heavy metals in contaminated soils from Spain. Soil Science and Plant Analysis, 33(15-18), 2781-2791.
Nancharaiah, Y. V., Schwarzenbeck, N., Mohan, T. V. K., Narasimhan, S. V., Wilderer, P. A. and Venugopalan, V. P. (2006) Biodegradation of nitrilotriacetic acid (NTA) and ferric–NTA complex by aerobic microbial granules. Water Research, 40(8), 1539-1546.
Neugschwandtner, R. W., Tlustos Komarek, M. and Sz akova, J. (2008). Phytoextraction of Pb and Cd from a contaaminated agricultural soil using different EDTA application regimes laboratory versus field scale measures of efficiency. Geoderma, 144(3-4), 446-454.
Nowack B., Schulin R., and Robinson B.H. (2006). Critical assessment of chelant-enhanced metal phytoextraction. Environmental Science and Technology, 40:5225-5232.
Potters, G., Pasternak, TP., Guisez, Y., Plame, KJ. and Jansen, M.A.K. (2007). Stress-indused morphogenic responses: growing out of trouble? Plant Science, 12, 98-105.
Quartacci, M. F., Baker, A. J. M. and Navari-Izzo, F. (2005). Nitriloacetate and citric acid assisted phytoextraction of cadmium by Indian mustard (Brassica juncea L.). Chemosphere, 59(9), 1249-1255.
Raju, K. M., Raju, M. P. and Mohan, Y. M. (2002). Synthesis and water absorbency of crosslinked superabsorbent polymers. Journal Applied Polymers Science, 85(8), 1795-1801.
Seregin I.V., and Kozhevnikova A.D. (2006). Physiological role of nickel and its toxic effects on higher plants. Russian Journal of Plant Physiology, 53:257-2.
Shahid, M., Pinelli, E. and Dumat, C. (2012). Review of Pb availability and toxicity to plants in relation with metal speciation, role of synthetic and natural organic ligands. Journal of Hazardous Materials, 219, 1-12.
Shakoor, M. B., Ali, S., Hameed, A., Farid, M., Hussain, S., Yasmeen, T. and Abbasi, G. H. (2014). Citric acid improves lead (Pb) phytoextraction in Brassica napus L. by mitigating Pb-induced morphological and biochemical damages. Ecotoxicology and Environmental Safety, 109, 38-47.
Shen, Z. G., Li, X. D., Wang, C. C., Chen, H. M., and Chua, H. (2002). Lead phytoextraction from contaminated soils with high-biomass plant species. Journal Environmental Quality, 31(6), 1893-1900.
Sheng, X.F., Xia, J.J., Jiang, C.Y., He, L.Y., and Qian, M. 2008. Characterization of heavy metal-resistant endophytic bacteria from rape (Brassica napus) roots and their potential in promoting the growth and lead accumulation of rape. Environment. Pollution. 156: 3. 1164-1170.
Sinegani, A.A.S., and Hosseinpur, A. (2010). Evaluation of effect of different sterilization methods on soil biomass phosphorus extracted with NaHCO3. Plant Soil Environ.
Sun, Y. B., Zhou, Q., Jing, A., Liu, W. and Liu, R. (2009). Chelator-enhanced phytoextraction of heavy metals from contaminated soil irrigated by industrial wastewater with the hyperaccumulator plant (sedum alfredii Hance). Geoderma, 150(1-2), 106-112.
Vamerali, T., Bandiera, M. and Mosca, G. (2010). Field crops for phytoremediation of metal-contaminated land, A review. Environmental Chemistry Letters, 8(1), 1-17.
Walkley, A. and Black, I. A. (1934). Examination of the degtjareff method determining soil organic matter and aproposed modification of the chromic acid titration method. Soil Science, 37(1), 29-38.
Woodhouse, J. and Johnson, M. S. 1991; Effect ofsuperabsorbent polymers on survival and growth of cropseedings. Agricultural Water Management. 20:63-70.
Wu, L. H., Luo, Y. M., Christie, P. and Wong, M. H. (2003). Effects of EDTA and low molecular weight organic acids on soil solution properties of a heavy metal polluted soil. ChemospHere, 50(6), 819-822.
Xia, H. J. (2004). Study on sand water retention improved polyacrylamide. Water Resour and Hydropower Northeast China, 22, 57–58.
Yusuf, M., Fariduddin, Q., Hayat, S., and Ahmad, A. 2011. Nickel: an overview of uptake, essentiality and toxicity in plants. Bulletin of Environmental Contamination and Toxicology, 86: 1-17.
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