Free Standard AU & NZ Shipping For All Book Orders Over $80!
Register      Login
Soil Research Soil Research Society
Soil, land care and environmental research
RESEARCH ARTICLE

Boron in humus and inorganic components of Hamra and Grumosol soils irrigated with reclaimed wastewater

F. S. Kot A B , R. Farran A , M. Kochva A and A. Shaviv A
+ Author Affiliations
- Author Affiliations

A Faculty of Civil and Environmental Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.

B Corresponding author. Email: fskot@tx.technion.ac.il

Soil Research 50(1) 30-43 https://doi.org/10.1071/SR11232
Submitted: 7 September 2011  Accepted: 16 January 2012   Published: 20 February 2012

Abstract

The role of organic matter in soil boron (B) turnover and availability is not well understood. The forms and mobility of B are of special concern in soils irrigated with reclaimed wastewaters (RWW). We studied B distribution and binding in major components of two irrigated Mediterranean soils, with special emphasis on humus and water-mobile phases. The results showed that most B in the sandy loam Hamra soil and a large part in the clayey calcareous Grumosol was bound to extractable humus fractions and, in the Grumosol, to organic/mineral refractory residue, along with fractions of free (non-silicate) iron/aluminium (Fe/Al) minerals and aluminosilicates. Among humus fractions, the major B carriers were humin, Fe/Al-humates (complexed firmly, presumably through polyvalent Fe/Al cations), and calcium/magnesium (Ca/Mg)-humates (bridged to soil particles through divalent cations), and to a much lesser extent fulvic-Fe/Al (Hamra) and fulvic-Ca/Mg (Grumosol) complexes. The mode of B preferential binding indicates an origin of the soil humus from lignin of plant cell walls and membranes. In water extract, B was bound firmly (non-exchangeable) to coarse colloids >0.20 μm, presumably of organic/bacterial origin. Boron was not detected in the exchangeable fraction. This raises the question of the forms of bioavailable B in the soils. It can be assumed that the bulk of B in the soil–plant system circulates among plants (lignin) and the inherited soil organic matter/humified material. It is noteworthy that irrigation with RWW resulted in a slight increase of mannitol-extractable B and a redistribution of humus-B in favour of firmly bound Fe/Al-humate complexes.


References

Agulhon H (1910) Présence et utilité du bore chez les vegetaux. Annales de l’Institut Pasteur 24, 321–329.

Aitken RL, Jeffrey AJ, Compton BL (1987) Evaluation of selected extractants for boron in some Queensland soils. Australian Journal of Soil Research 25, 263–273.
Evaluation of selected extractants for boron in some Queensland soils.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2sXlslCqurc%3D&md5=94ad0a3c97d9f20ea0e18961edda025eCAS |

Aleksandrova LN (1980) ‘Soil organic matter and the processes of its transformation.’ (Nauka: Leningrad) [in Russian]

Allison LE (1965) Organic carbon. In ‘Methods of soil analysis, part 2. Chemical and microbiological properties’. No. 9 in the series ‘Agronomy’, (Eds CA Black et al.) pp. 1367–1378. (American Society of Agronomy: Madison, WI)

Asad A, Bell RW, Dell B, Huang L (1997) Development of a boron buffered solution culture system for controlled studies of plant boron nutrition. Plant and Soil 188, 21–32.
Development of a boron buffered solution culture system for controlled studies of plant boron nutrition.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXjvFOqs74%3D&md5=38af24a30403c66f9db3f37b89e15540CAS |

Barber SA (1984) ‘Soil nutrient bioavailability’. (John Wiley and Sons: New York)

Bell RW (1997) Diagnosis and prediction of boron deficiency for plant production. Plant and Soil 193, 149–168.
Diagnosis and prediction of boron deficiency for plant production.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXmtFaltbg%3D&md5=d7a2c36e192202717842a01132ecec8cCAS |

Berger KC, Pratt PJ (1963) Advances in secondary and micro nutrient fertilization. In ‘Fertilizer technology and use’. (Eds JH McVickar et al.) pp. 281–340. (Soil Science Society of America: Madison, WI)

Bernstein N, Chaimovitch D, Dudai N (2009) Effect of irrigation with secondary treated effluent on essential oil, antioxidant activity, and phenolic compounds in oregano and rosemary. Agronomy Journal 101, 1–10.
Effect of irrigation with secondary treated effluent on essential oil, antioxidant activity, and phenolic compounds in oregano and rosemary.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXjtFGhsb0%3D&md5=e66c67e627b68da8a2df308c5da2eb63CAS |

Blaser-Grill J, Knoppik D, Amberger A, Goldbach H (1989) Influence of boron on the membrane potential in Elodea densa and Helianthus annuus roots and H+ extrusion of suspension cultured Daucus carota cells. Plant Physiology 90, 280–284.
Influence of boron on the membrane potential in Elodea densa and Helianthus annuus roots and H+ extrusion of suspension cultured Daucus carota cells.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL1MXktlKku7o%3D&md5=f673971ba9d1db0d73a878b7f981f35cCAS |

Bolaños L, Lukaszewski K, Bonilla I, Blevins D (2004) Why boron? Plant Physiology and Biochemistry 42, 907–912.
Why boron?Crossref | GoogleScholarGoogle Scholar |

Bower CA, Wilcox LV (1965) Soluble salts. In ‘Methods of soil analysis, part 2. Chemical and microbiological properties’. No. 9 in the series ‘Agronomy’. (Eds CA Black et al.) pp. 933–951. (American Society of Agronomy: Madison, WI)

Bremner JM, Heintze SG, Mann PJG, Lees H (1946) Metallo-organic complexes in soil. Nature 158, 790–791.
Metallo-organic complexes in soil.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaH2sXms1Kh&md5=7fabb482f7ecfb2a3a4a3c5a57302414CAS |

Buffle J, Perret D, Newman M (1992) The use of filtration and ultrafiltration for size fractionation of aquatic particles, colloids and macromolecules. In ‘Environmental particles’. (Eds J Buffle, HP Van Leeuwen) pp. 171–230. (Lewis: Boca Raton, FL)

Cameron RS, Thornton BK, Swift RS, Posner AM (1972) Molecular weight and shape of humic acid from sedimentation and diffusion measurements on fractional extracts. European Journal of Soil Science 23, 394–408.
Molecular weight and shape of humic acid from sedimentation and diffusion measurements on fractional extracts.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE38Xls1emtbc%3D&md5=19bb64058f078978ad68515d632d091eCAS |

Cartwright B, Zarcinas BA, Mayfield AH (1984) Toxic concentrations of boron in a red-brown earth at Gladstone, South Australia. Australian Journal of Soil Research 22, 261–272.
Toxic concentrations of boron in a red-brown earth at Gladstone, South Australia.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2cXlsVGms74%3D&md5=15d9f6970e5283f807fa9d1d24e673b9CAS |

Chen Y, Senesi N, Schnitzer M (1977) Information provided on humic substances by E4/E6 ratios. Soil Science Society of America Journal 41, 352–358.
Information provided on humic substances by E4/E6 ratios.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE2sXks1Oitr4%3D&md5=47dbf0fa1aa33536c61b9c524d04bdc4CAS |

Cheng W, Coleman DC (1990) Effect of living roots on soil organic matter decomposition. Soil Biology & Biochemistry 22, 781–787.
Effect of living roots on soil organic matter decomposition.Crossref | GoogleScholarGoogle Scholar |

Chin Y-P, Aiken G, O’Laughlin E (1994) Molecular weight, polydispersity, and spectroscopic properties of aquatic humic substances. Environmental Science & Technology 28, 1853–1858.
Molecular weight, polydispersity, and spectroscopic properties of aquatic humic substances.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2cXls1ems7g%3D&md5=111ab6599e7e6ed9d01c480a9635550fCAS |

de Abreu CA, de Abreu MF, van Raij B, Bataglia OC (1994) Extraction of boron from soil by microwave heating for ICP-AES determination. Communications in Soil Science and Plant Analysis 25, 3321–3333.
Extraction of boron from soil by microwave heating for ICP-AES determination.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2MXisVWmtro%3D&md5=99595c400dc58913ae10f2ffbd899b02CAS |

De Haan H (1977) Effect of benzoate on microbial decomposition of fulvic acids in Tjeukemeer (The Netherlands). Limnology and Oceanography 22, 38–44.
Effect of benzoate on microbial decomposition of fulvic acids in Tjeukemeer (The Netherlands).Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE2sXhs1Olsb4%3D&md5=d6c42bda621fbc5912aded2c29d1bf2bCAS |

Dembitsky VM, Smoum R, Al-Quntar AA, Abu Ali H, Pergament I, Srebnik M (2002) Natural occurrence of boron-containing compounds in plants, algae and microorganisms. Plant Science 163, 931–942.
Natural occurrence of boron-containing compounds in plants, algae and microorganisms.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XosFeqsbg%3D&md5=467e979f704e19b63ce81f293c1d1e95CAS |

Dordas C, Brown PH (2000) Permeability of boric acid across lipid bilayers and factors affecting it. The Journal of Membrane Biology 175, 95–105.
Permeability of boric acid across lipid bilayers and factors affecting it.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3cXjsF2gurc%3D&md5=668fbb19efc01c39b11f5a58302e59deCAS |

Downing RG, Strong PL, Hovanec BM, Northington J (1998) Considerations in the determination of boron at low concentrations. Biological Trace Element Research 66, 3–21.
Considerations in the determination of boron at low concentrations.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1MXht1Cit74%3D&md5=b3ecca79f5f47452bcc1bd29cd739fb0CAS |

Duchaufour P (1977) ‘Pedology. 1. Pedogenesis and classification.’ (Allen and Unwin: London, Boston)

Eaton FM, Wilcox LV (1939) ‘The behavior of B in soils.’ U.S. Department of Agriculture Technical Bulletin No. 696. (USDA: Washington, DC)

Goldbach HE, Wimmer MA (2007) Boron in plants and animals: Is there a role beyond cell-wall structure? Journal of Plant Nutrition and Soil Science 170, 39–48.
Boron in plants and animals: Is there a role beyond cell-wall structure?Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXjtFylu7o%3D&md5=66b26d085923ef695cc21a1c3727e918CAS |

Goldschmidt VM (1937) The principles of distribution of chemical elements in minerals and rocks. Journal of the Chemical Society 665–673.

Greenland DJ (1971) Interactions between humic and fulvic acids and clays. Soil Science 111, 34–41.
Interactions between humic and fulvic acids and clays.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE3MXls1Siuw%3D%3D&md5=5211d888ec0c83d01ef915fb14a0f60aCAS |

Gupta U, Gupta C, Jame YW, Campbell CA, Leyshon AJ, Nicholaichuk W (1985) Boron toxicity and deficiency: a review. Canadian Journal of Soil Science 65, 381–409.
Boron toxicity and deficiency: a review.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2MXlsF2murg%3D&md5=759a45714cf0e0daf76c50d50991fcdeCAS |

Han FX, Banin A (1995) Selective sequential dissolution techniques for trace metals in arid-zone soils: The carbonate dissolution step. Communications in Soil Science and Plant Analysis 26, 553–576.
Selective sequential dissolution techniques for trace metals in arid-zone soils: The carbonate dissolution step.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2MXjslKrsro%3D&md5=a46390a80288a97cf32dafd13d68c446CAS |

Hingston FJ (1964) Reactions between boron and clays. Australian Journal of Soil Research 2, 83–95.
Reactions between boron and clays.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaF2cXkvVygtb4%3D&md5=8a36488b2a5c05e710eee78d6f1e8750CAS |

Hou J, Evans LJ, Spiers GA (1994) Boron fractionation in soils. Communications in Soil Science and Plant Analysis 25, 1841–l853.
Boron fractionation in soils.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2cXktVyjt7Y%3D&md5=ca7555064983b0fed4838997bddaa365CAS |

Hou J, Evans LJ, Spiers GA (1996) Chemical fractionation of soil boron: I. Method development. Canadian Journal of Soil Science 76, 485–491.
Chemical fractionation of soil boron: I. Method development.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXjtVehtg%3D%3D&md5=86f12a56c6280437da8080b835be473cCAS |

Hu H, Brown PH (1997) Absorption of boron by plant roots. Plant and Soil 193, 49–58.
Absorption of boron by plant roots.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXmtFalt7w%3D&md5=54118599ab501b2a654887085a0f6892CAS |

Kawaguchi K, Kyuma K (1959) On the complex formation between soil humus and polyvalent cations. Soil and Plant Food 5, 54–63.

Keren R, Communar G (2009) Boron transport in soils as affected by dissolved organic matter in treated sewage effluent. Soil Science Society of America Journal 73, 1988–1994.
Boron transport in soils as affected by dissolved organic matter in treated sewage effluent.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXhsVSku7jN&md5=36c24ae20cde5c3184eb03ce70113640CAS |

Kononova MM (1966) ‘Soil organic matter.’ (Pergamon: Elmsford, NY)

Kot FS (2009) Boron sources, speciation and its potential impact on health. Reviews in Environmental Science and Biotechnology 8, 3–28.
Boron sources, speciation and its potential impact on health.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXitVOrtbs%3D&md5=5ffa5e17eac5be4d349e4c617d13f2faCAS |

Kovda VA (1973) ‘Fundamentals of soil science. Vol. 2.’ (Nauka: Moscow) [in Russian]

Kretzschmar R, Schäfer T (2005) Metal retention and transport on colloid particles in the environment. Elements 1, 205–210.
Metal retention and transport on colloid particles in the environment.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXhtVGiu7vL&md5=cce60a26e29c62827d78505fb6954111CAS |

Kunin R, Preuss AF (1964) Characterization of a boron specific ion exchange resin. I & EC Product Research for Development 3, 304–306.

Lehto T, Ruuhola T, Dell B (2010) Boron in forest trees and forest ecosystems. Forest Ecology and Management 260, 2053–2069.
Boron in forest trees and forest ecosystems.Crossref | GoogleScholarGoogle Scholar |

Lemarchand E, Schott J, Gaillardet J (2005) Boron isotopic fractionation related to boron sorption on humic acid and the structure of surface complexes formed. Geochimica et Cosmochimica Acta 69, 3519–3533.
Boron isotopic fractionation related to boron sorption on humic acid and the structure of surface complexes formed.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXmtlKltbk%3D&md5=4e5f4415d9303d13c9d29f50b71417cbCAS |

Lindsay WL (1972) Inorganic phase equilibria of micronutrients in soils. In ‘Micronutrients in agriculture’. (Eds JJ Mortvedt, PM Giordano, WL Lindsay) pp. 41–57. (Soil Science Society of America: Madison, WI)

Martin JM, Nirel P, Thomas AJ (1987) Sequential extraction techniques: Promises and problems. Marine Chemistry 22, 313–341.
Sequential extraction techniques: Promises and problems.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL1cXht1ensLw%3D&md5=e959ac83740bc1baf4f633e6a5898f25CAS |

Matoh T, Ishigaki K, Mizutani M, Matsunaga W, Takabe K (1992) Boron nutrition of cultured tobacco BY-2 cells. I. Requirement for and intracellular localisation of boron and selection of cells that tolerate low levels of boron. Plant & Cell Physiology 33, 1135–1141.

McGeehan SL, Topper K, Naylor DV (1989) Sources of variation in hot water extraction and colorimetric determination of soil boron. Communications in Soil Science and Plant Analysis 20, 1777–1786.
Sources of variation in hot water extraction and colorimetric determination of soil boron.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL1MXmtlWhs7g%3D&md5=2897ce3f8d36de52e650258731159a10CAS |

Mehra PO, Jackson ML (1960) Iron oxide removal from soils and clays by a dithionite–citrate system with sodium bicarbonate buffer. Clays and Clay Minerals 7, 317–327.
Iron oxide removal from soils and clays by a dithionite–citrate system with sodium bicarbonate buffer.Crossref | GoogleScholarGoogle Scholar |

Michalke B (1999) Quality control and reference materials in speciation analysis. Fresenius’ Journal of Analytical Chemistry 363, 439–445.
Quality control and reference materials in speciation analysis.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1MXhvFGms7s%3D&md5=da154c4588f7317864f9877721c9c1feCAS |

Miller RO, Vaughan B (1999) ‘Extraction of soil boron with DTPA-sorbitol.’ (ASA: Salt Lake City, UT)

Nable RO, Bañuelos GS, Paull JG (1997) Boron toxicity. Plant and Soil 193, 181–198.
Boron toxicity.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXmtFalu7g%3D&md5=129cf684e5d734202ac61866f3b324a6CAS |

Novozamsky I, Barrera LL, Houba VJ, Vanderlee JJ, Eck R (1990) Comparison of a hot water and cold 0.01 M CaCl2 extraction procedures for the determination of boron in soil. Communications in Soil Science and Plant Analysis 21, 2189–2195.
Comparison of a hot water and cold 0.01 M CaCl2 extraction procedures for the determination of boron in soil.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK3MXmtVyqsw%3D%3D&md5=13049943ea3817345e8d5e48d4fcada2CAS |

Orlov DS (1985) ‘Humus acids of soils.’ (A.A. Balkema: Rotterdam)

Oved T, Shaviv A, Goldrath T, Mandelbaum RT, Minz D (2001) Influence of effluent irrigation on community composition and function of ammonia-oxidizing bacteria in soil. Applied and Environmental Microbiology 67, 3426–3433.
Influence of effluent irrigation on community composition and function of ammonia-oxidizing bacteria in soil.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXlvFSltbs%3D&md5=4ed048f5f3169bd0314cd7fe4de681c8CAS |

Peech M (1965) Hydrogen-ion activity. In ‘Methods of soil analysis, part 2. Chemical and microbiological properties’. No. 9 in the series ‘Agronomy’. (Eds CA Black et al.) pp. 914–926. (American Society of Agronomy: Madison, WI)

Ponomareva VV, Plotnikova TA (1980) ‘Humus and soil formation.’ (Nauka: Leningrad) [in Russian]

Power PP, Woods WG (1997) Absorption of boron by plant roots. Plant and Soil 193, 49–58.
Absorption of boron by plant roots.Crossref | GoogleScholarGoogle Scholar |

Preston CM, Hempfling R, Schulten H-R, Schnitzer M, Trofymow JA, Axelson DE (1994) Characterization of organic matter in a forest soil of coastal British Columbia by NMR and pyrolysis-field ionization mass spectrometry. Plant and Soil 158, 69–82.
Characterization of organic matter in a forest soil of coastal British Columbia by NMR and pyrolysis-field ionization mass spectrometry.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2cXitFGqtL8%3D&md5=28890d45dadce2de2b29514a06823d8eCAS |

Raza M, Mermut AR, Schoenau JJ, Malhi SS (2002) Boron fractionation in some Saskatchewan soils. Canadian Journal of Soil Science 82, 173–179.
Boron fractionation in some Saskatchewan soils.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XkvFegt70%3D&md5=05d7a04f71c11643b3229b4523af9c89CAS |

Russell EW, Russell EJ (1961) ‘Soil conditions and plant growth.’ (Longmans, Green & Co. Ltd: London)

Sah RN, Brown PH (1997) Boron determination—a review of analytical methods. Microchemical Journal 56, 285–304.
Boron determination—a review of analytical methods.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXkslWksbk%3D&md5=6425c07fab54ba83c9bca162f6e6d0d8CAS |

Salomons W, Förstner U (1984) ‘Metals in the hydrocycle.’ (Springer-Verlag: Berlin)

Schallinger KM (1984) Studies of humus materials in Israeli soils. In ‘Volunteered Papers of the 2nd International Conference of the International Humic Substances Society’. Birmingham, UK. (Eds MHB Hayes, RS Swift) pp. 263–264. (The Printing Section, The University of Birmingham: UK)

Schnitzer M, Khan SU (1972) ‘Humic substances in the environment.’ (Marcel Dekker: New York)

Schwertmann U (1964) Differentiation of iron oxide in soils by a photochemical extraction with acid ammonium oxalate. Zeitschrift für Pflanzenernährung und Bodenkunde 105, 194–201.

Shiffler AK, Jolley VD, Christopherson JE, Webb BL, Farrer DC, Haby VA (2005) Pressurized hot water and DTPA-sorbitol as viable alternatives for soil boron extraction. I. Boron-treated soil incubation and efficiency of extraction. Communications in Soil Science and Plant Analysis 36, 2179–2187.
Pressurized hot water and DTPA-sorbitol as viable alternatives for soil boron extraction. I. Boron-treated soil incubation and efficiency of extraction.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXhtVSlsLvO&md5=e336e7c640d2c274acbb471e3ca71452CAS |

Shorrocks VM (1997) The occurrence and correction of boron deficiency. Plant and Soil 193, 121–148.
The occurrence and correction of boron deficiency.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXmtFaltbo%3D&md5=84fb94c809d2596d624811f35e2908d4CAS |

Singer A (2007) ‘The soils of Israel.’ (Springer-Verlag: Berlin, Heidelberg)

Sørensen LH (1974) Rate of decomposition of organic matter in soil as influenced by repeated air-drying-rewetting and repeated additions of organic material. Soil Biology & Biochemistry 6, 287–292.
Rate of decomposition of organic matter in soil as influenced by repeated air-drying-rewetting and repeated additions of organic material.Crossref | GoogleScholarGoogle Scholar |

Spouncer LR, Nable RO, Cartwright B (1992) A procedure for the determination of soluble boron in soils ranging widely in boron concentrations, sodicity, and pH. Communications in Soil Science and Plant Analysis 23, 441–453.
A procedure for the determination of soluble boron in soils ranging widely in boron concentrations, sodicity, and pH.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK38XitFemsro%3D&md5=c0d0ad0245310db9f995aec1a171be9cCAS |

Steinberg C, Münster U (1985) Geochemistry and ecological role of humic substances in lakewater. In ‘Interactions at the soil colloid – soil solution interface’. (Eds GH Bolt et al.) pp. 105–145.

Stevenson FJ (1994) ‘Humus chemistry, genesis, composition, reactions.’ (John Wiley & Sons: Hoboken, NJ)

Su C, Suarez DL (1995) Coordination of adsorbed boron: A FTIR spectroscopic study. Environmental Science & Technology 29, 302–311.
Coordination of adsorbed boron: A FTIR spectroscopic study.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2MXivFOrsrY%3D&md5=34207e98b2ac46dd1ae2ce49040909a3CAS |

Swift RS (1996) Organic matter characterization. In ‘Methods of soil analysis. Part 3. Chemical methods’. Soil Science Society of America Book Series 5. (Eds DL Sparks et al.) Ch. 35. pp. 1018–1020. (Soil Science Society of America: Madison, WI)

Szücs L, Elek E (1962) Data on trace element content of chernozems in Hungary. Agrokémiai Talajt 11, 311–322. [in Hungarian, English abstract]

Tack FM, Verloo MG (1995) Chemical speciation and fractionation in soil and sediment heavy metal analysis: A review. International Journal of Environmental Analytical Chemistry 59, 225–238.
Chemical speciation and fractionation in soil and sediment heavy metal analysis: A review.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2MXos1aks7g%3D&md5=c768bed95ae3a7aa5cfedbbde6512097CAS |

Tamm O (1922) Eine Methode zur Bestimmung der anorganischen Komponente des Gelkomplexes im Boden. Meddelanden av Statens Skogsförsöksanst 19, 387–404.

Tanaka M, Fujiwara T (2008) Physiological role and transport mechanisms of boron: Perspectives from plants. Pflügers Archiv–European Journal of Physiology 456, 671–677.
Physiological role and transport mechanisms of boron: Perspectives from plants.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXlvVChtrw%3D&md5=b2f59a5576cb14ec05e1699e3220aec8CAS |

Tessier A, Campbell PGC, Bisson M (1979) Sequential extraction procedure for the speciation of particulate trace metals. Analytical Chemistry 51, 844–851.
Sequential extraction procedure for the speciation of particulate trace metals.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE1MXitV2rtr4%3D&md5=511070d49d4c2ab304adbcbb6a9e9869CAS |

Treeby M, Marschner H, Römheld V (1989) Mobilization of iron and other micronutrient cations from a calcareous soil by plant-borne, microbial, and synthetic metal chelators. Plant and Soil 114, 217–226.
Mobilization of iron and other micronutrient cations from a calcareous soil by plant-borne, microbial, and synthetic metal chelators.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL1MXksFKgu7w%3D&md5=6ec6e7bc280ec346f216fd61261ab14eCAS |

Tyurin IV (1937) Organic matter in soils and its role in pedogenesis and fertility. In ‘Study of soil humus’. (Selkhozgis: Moscow) [in Russian]

Viets FG (1962) Chemistry and availability of micronutrients in soils. Journal of Agricultural and Food Chemistry 10, 174–178.
Chemistry and availability of micronutrients in soils.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaF38XksFWitbs%3D&md5=f6ce301c87d6a879f119acf5231e427bCAS |

Waksman SA (1936) ‘Humus. Origin, chemical composition, and importance in nature.’ (The Williams & Wilkins: Baltimore, MD)

Yermiyahu U, Keren R, Chen Y (2001) Effect of composted organic matter on boron uptake by plants. Soil Science Society of America Journal 65, 1436–1441.
Effect of composted organic matter on boron uptake by plants.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XptlWj&md5=a01ae39cdfaf05f9ff05350fe222a717CAS |