Boron is an essential element for plant growth. Soluble and adsorbed boron are short- and long-time sources of B for plants. Adsorbed B controls equilibrium concentration and its deficiency and toxicity in soils. Considering the importance of adsorption and desorption reactions in B behavior in soils, boron adsorption isotherms were measured in five soils differed in calcium carbonate equivalent (CCE 0-80%). Experimental data were described with linear and non-linear forms of the Langmuir, Freundlich, Toth, and Langmuir-Freundlich equations. Analysis of the model descriptions revealed that the Langmuir equation was the best equation for prediction of the exerimental data. The latter data and the predictions by the Langmuir equation showed that boron was weakly adsorbed in soils when compared with other oxyanions. Boron adsorption maximum () was calculated between 1 to 3 µmol /g soil. Correlating boron adsorption maximum with soil properties revealed that the amount of adsorbed B was not a simple function of the soil properties, rather, it reflected the effect of different soil properties such as pH, texture, carbonates and oxides contents. Among soil properties, active CCE showed a direct relationship with boron adsorption maximum. Removing calcium carbonates from a soil sample (18% CCE and pH 7.4) reduced boron adsorption maximum by 35%. In addition, the effect of three levels of ionic strength i.e. 0.01, 0.1 and 0.5 M NaCl, was measured in a soil sample. The results revealed that B adsorption maximum increased by 24 and 71% with increasing ionic strength from 0.01 to 0.1 and 0.5 M. This could be due to an increase in pH-dependent surface charges and/or a decrease in the thickness of the double layer. |
- ملکوتی، م. ج. و پ. کشاورز. (1384). نگرشی بر حاصلخیزی خاکهای ایران " شناسایی و بهرهبرداری" چاپ اول، 503 صفحه. وزارت جهاد کشاورزی، موسسه تحقیقات خاک و آب. تهران، ایران
- ﻋﻠﻲ اﺣﻴﺎﻳﻲ، م . و ع. ا. ﺑﻬﺒﻬﺎﻧﻲ زاده . 1372 . ﺷﺮح روشﻫﺎی ﺗﺠﺰﻳﻪ شیمیاییﺧﺎک. ﻧـﺸﺮﻳﻪ 893. ﻣﻮﺳسه ﺗﺤﻘﻴﻘـﺎت ﺧـﺎک و آب. تهران.
- Arora, H., S. S. Bhardwaj and B. D. Sharma. 2006. Bor on adsorption on benchmark soils of Punjab. Asian Journal of Chemistry 18(2): 1313-1320.
- Bohn, H. L., B. L. McNeal, and G. A. O`Coner. 1985. Soil Chemistry. New York : Wiley.
- Coffin, D. E. 1963. A method for the determination of free iron in soils and clays. Canadian Journal of Soil Science 42: 7-17.
- Elrashidi, M. A., and G. A. O. Connor. 1982. Boron sorption and desorption in soils. Soil Science Society of American Journal 46: 27-31.
- Goldberg, S., and H. S. Forster. 1991. Boron sorption on calcareous soils and reference calcites. Soil Science 152(4): 304-310.
- Goldberg, S., H. S. Forster and E. L. Heick. 1993. Boron adsorption mechanisms on oxides, clay-minerals, and soils inferred from ionic-strength effects. Soil Science Society of American Journal 57(3): 704-708.
- Goldberg, , H. S. Forster and E. L. Heick. 1993. Temperature effects on boron adsorption by reference minerals and oils. Soil Science 156(5): 316-321.
- Goldberg, S. and R. A. Glaubig. 1986. Boron adsorptoin and silicon release by clay minerals kaolinite, montmorillonite, and illite. Soil Science Society of American Journal 50: 1442-1448.
- Goldberg, S., S. M. Lesch and D. L. Suarez. 2001. Predicting boron adsorption by soils using soil chemical parameters in the constant capacitance model. Soil Science Society of America Journal 64(6): 1356-1363.
- Goldberg, S., S. M. Lesch, D. L. Suarez, and N. T. Basta. 2005. Predicting arsenate adsorption by soils using soil chemical parameters in the constant capacitance model. Soil Science Society of America Journal 69(5): 1389-1398.
- Hingston, F. J. 1964. Reactions between boron and clays. Australian Journal of Soil Research 2: 83-95.
- Ichikuni, M., and K. Kikuchi. 1972. Retention of B by travertines. Chem. Geol. 9(13-21)
- Jin, J.Y., D. C. Martens, and L. Zelazny. 1987. Distrbition and plant availability of soil boron fractions. Soil Science Society of American Journal 51: 1228-1231.
- Keren, R., and F. T. Bingham. 1985. Boron in soils, water and plants. Advance Soil Science 1(229-276)
- Keren, R., and R. G. 1981. Effects of wetting and drying, and of exchangeable cation, on boron adsorption and releas by montmorilonite. Soil Science Society of American Journal 45(478-482)
- Keren, R., and R. G. O`Conner. 1982. Effect of exchangable ions and ionic strength on boron adsorption by montmorillonite and illite. Clays and Clay Minerals 30: 341-346.
- Keren, R., and D. L. Sparks. 1994. Effect of pH and ionic strength on Boron adsorption by pyrophyllite. Soil Science Society of American Journal 58: 1095-1100.
- Keren, R., and H. Talpaz. 1984. Boron adsorption by montmorillonite as affected by particle size. Soil Science Society of America Journal 48(3): 555-559.
- Kinniburgh, D. G. 1986. General purpose adsorption isotherms. Environment Science Technology 20: 895-904.
- Kosmulski, M. 2001. Chemical properties of material surfaces. Marcel Dekker, Inc., New york.
- Kunze, G. W., and B. J. Dixon. 1986. pretreatment for mineralogycal analysis. In Methods of Soil Analysis, part 1. 2d ed. A. Klute (ed.). Agronomy 9: 91-100.
- Loeppert, R. H. and D. L. Suarez. 1996. Methods of Soil Analysis. part 3. Chemical Methods. Soil Science Society of America and American Society of Agronomy Madison.
- Page, A. L., R. H. Miller, and D. R. Keeney. 1982. Methods of Soil Analysis, part2, chemical and microbiological properties. American Society of Agronomy,Inc. Soil Science ofAamerica, Madison, WI.
- Peak, D., G. W. Luther, and D. L. Sparks. 2003. ATR-FTIR spectroscopic studies of boric acid adsorption on hydrous ferric oxide. Geochimica Et Cosmochimica Acta 67(14): 2551-2560.
- Schwertm, U. 1973. Use of oxalate for fe Extraction from soils. Canadian Journal of Soil Science 53(2): 244-246.
- Sims, J. R., and F. T. Bingham. 1967. Retention of boron by layer silicates, sesquioxides, and soil materials: I. Layer silicates. Soil Science Society of American Journal 31: 728-732.
- Sims, J. R., and F. T. Bingham. 1968. Retention of boron by layer silicates, sesquioxides, and soil materials : II. sesquioxides. Soil Science Society of American Journal 32: 364-369.
- Su, C. M., and D. L. Suarez. 1995. Coordination of adsorbed boron - a Ftir spectroscopic study. Environmental Science & Technology 29(2): 302-311.
- Xu, D. N., and D. Peak. 2007. Adsorption of boric acid on pure and humic acid coated am-Al(OH)(3): A boron K-edge XANES study. Environmental Science & Technology 41(3): 903-908.
|