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RESEARCH ARTICLE

Predicting pH buffering capacity of New Zealand soils from organic matter content and mineral characteristics

Denis Curtin A C and Stephen Trolove B
+ Author Affiliations
- Author Affiliations

A The New Zealand Institute for Plant & Food Research Limited, Private Bag 4704, Christchurch, New Zealand.

B The New Zealand Institute for Plant & Food Research Limited, Private Bag 1401, Havelock North, New Zealand.

C Corresponding author. Email: denis.curtin@plantandfood.co.nz

Soil Research 51(6) 494-502 https://doi.org/10.1071/SR13137
Submitted: 2 May 2013  Accepted: 31 August 2013   Published: 14 November 2013

Abstract

Information on the pH buffer capacity of soil is required to estimate changes in pH due to acidic or alkaline inputs, and to model pH-dependent processes within the soil nitrogen (N) cycle. The objective was to determine whether a model based on soil organic matter (SOM) and mineral characteristics (clay content, extractable iron (Fe) and aluminium (Al)) would be adequate to estimate the buffer capacities of New Zealand soils. We measured pH changes in 34 soils, representing a range of SOM and texture, after equilibration with several rates (range 0–15 cmol OH kg–1 soil) of either KOH or Ca(OH)2. The Ca(OH)2 method often yielded higher buffer capacity values than the KOH method, possibly because of incomplete reaction of Ca(OH)2, especially at high addition rates. Buffer capacity (measured using KOH) of the soils was strongly correlated with soil carbon (C) (R2 = 0.76), and weakly (but significantly, P < 0.05) with clay content, and with dithionite extractable Fe and Al. A regression with soil C, clay, and P-retention (a surrogate for extractable Al and Fe) as independent variables explained 90% of the variability in pH buffering. The role of organic matter was further evaluated by measuring buffer capacity of soil from research plots at Lincoln, Canterbury, New Zealand, that differed in C (21–37 g C kg–1 in the top 7.5 cm; 19–26 g C kg–1 in the 7.5–15 cm) as a result of the treatments imposed during the 12-year trial period. A substantial decrease in pH buffering (by up to 24% in top 7.5 cm) was associated with a decline in SOM following the conversion of permanent pasture (pre-trial land use) to arable cropping. Across all treatments and sampling depths, buffer capacity was linearly related (R2 = 0.84, P < 0.001) to soil C; the estimated buffer capacity of SOM was 89 cmolc kg–1 C pH unit–1, similar to the value calculated from the previous study with different soil types. After 12 years, treatments with low soil C concentrations tended to be more acidic, possibly partly because of weaker pH buffering.

Additional keywords: cation exchange capacity, phosphate retention, sesquioxides, soil C, texture, titratable acidity.


References

Aitken RL (1992) Relationships between extractable A1, selected soil properties, pH buffer capacity and lime requirement in some acidic Queensland soils. Australian Journal of Soil Research 30, 119–130.
Relationships between extractable A1, selected soil properties, pH buffer capacity and lime requirement in some acidic Queensland soils.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK38XitlCms7o%3D&md5=a2ced71195a6b5da624ec98ab402d53bCAS |

Aitken RL, Moody PW (1994) The effect of valence and ionic-strength on the measurement of pH buffer capacity. Australian Journal of Soil Research 32, 975–984.
The effect of valence and ionic-strength on the measurement of pH buffer capacity.Crossref | GoogleScholarGoogle Scholar |

Aitken RL, Moody PW, McKinley PG (1990) Lime requirement of acidic Queensland soils.1. Relationships between soil properties and pH buffer capacity. Australian Journal of Soil Research 28, 695–701.
Lime requirement of acidic Queensland soils.1. Relationships between soil properties and pH buffer capacity.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK3MXmsFGjt7c%3D&md5=30e918d5c23fed608a856850ffe2aa34CAS |

Bolan NS, Adriano DC, Curtin D (2003) Soil acidification and liming interactions with nutrient and heavy metal transformation and bioavailability. Advances in Agronomy 78, 215–272.
Soil acidification and liming interactions with nutrient and heavy metal transformation and bioavailability.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXjsl2nsbY%3D&md5=c970bd1e42106a9ea4993250fec94de3CAS |

Bouman OT, Curtin D, Campbell CA, Biederbeck VO, Ukrainetz H (1995) Soil acidification from Long-term use of anhydrous ammonia and urea. Soil Science Society of America Journal 59, 1488–1494.
Soil acidification from Long-term use of anhydrous ammonia and urea.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2MXotFOnsrs%3D&md5=307e40bef4f1a262028e6107d52932f9CAS |

Clough TJ, Sherlock RR, Mautner MN, Milligan DB, Wilson PF, Freeman CG, McEwan MJ (2003) Emission of nitrogen oxides and ammonia from varying rates of applied synthetic urine and correlations with soil chemistry. Australian Journal of Soil Research 41, 421–438.
Emission of nitrogen oxides and ammonia from varying rates of applied synthetic urine and correlations with soil chemistry.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXlslOgt7k%3D&md5=ba9a85b623dd62e1618eb1c792acde1dCAS |

Coleman NT, Thomas GW (1964) Buffer curves of acid clays as affected by the presence of ferric iron and aluminum. Soil Science Society of America Proceedings 28, 187–190.
Buffer curves of acid clays as affected by the presence of ferric iron and aluminum.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaF2cXktFSgur4%3D&md5=ca7ee1618a6ca1c924b6e0a2dd6d6650CAS |

Curtin D, Campbell CA, Messer D (1996) Prediction of titratable acidity and soil sensitivity to pH change. Journal of Environmental Quality 25, 1280–1284.
Prediction of titratable acidity and soil sensitivity to pH change.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK28XnsVyku70%3D&md5=f868accb287c5499082ef1e8844c3e0eCAS |

Edmeades DC, Wheeler DM, Waller JE (1985) Comparison of methods for determining lime requirements of New Zealand soils. New Zealand Journal of Agricultural Research 28, 93–100.
Comparison of methods for determining lime requirements of New Zealand soils.Crossref | GoogleScholarGoogle Scholar |

Ferguson RB, Kissel DE, Koelliker JK, Basel W (1984) Ammonia volatilization from surface-applied urea—Effect of hydrogen-ion buffering capacity. Soil Science Society of America Journal 48, 578–582.
Ammonia volatilization from surface-applied urea—Effect of hydrogen-ion buffering capacity.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2cXkslWltL0%3D&md5=5ecc98458627cb73e877a4db765438d8CAS |

Fraser PM, Curtin D, Beare MH, Meenken ED, Gillespie RN (2010) Temporal changes in soil surface elevation under different tillage systems. Soil Science Society of America Journal 74, 1743–1749.
Temporal changes in soil surface elevation under different tillage systems.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXht1CmsrrL&md5=5b33741c0c6b2e6f1dc4013788f978a8CAS |

Gee GW, Or D (2002) Particle size analysis. In ‘Methods of soil analysis. Part 4: Physical methods’. (Eds JH Dane, GC Topp) pp. 255–293. (Soil Science Society of America: Madison, WI)

Helling CS, Chesters G, Corey RB (1964) Contribution of organic matter and clay to soil cation exchange capacity as affected by pH of the saturating solution. Soil Science Society of America Proceedings 28, 517–520.
Contribution of organic matter and clay to soil cation exchange capacity as affected by pH of the saturating solution.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaF2cXks1yhtr0%3D&md5=d6363ba35beb8e64ce6c5a10b73732ebCAS |

Izaurralde RC, Kissel DE, Cabrera ML (1987) Titratable Acidity to Estimate Ammonia Retention. Soil Science Society of America Journal 51, 1050–1054.
Titratable Acidity to Estimate Ammonia Retention.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2sXlsFegtbg%3D&md5=81ef41ec90437da68e9c504472f55898CAS |

James BR, Riha SJ (1986) pH buffering in forest soil organic horizons—relevance to acid precipitation. Journal of Environmental Quality 15, 229–234.
pH buffering in forest soil organic horizons—relevance to acid precipitation.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL28XltVSlu74%3D&md5=dee8431da700e47bda8049e6f944cc89CAS |

Kissel DE, Sonon L, Vendrell PF, Isaac RA (2009) Salt concentration and measurement of soil pH. Communications in Soil Science and Plant Analysis 40, 179–187.
Salt concentration and measurement of soil pH.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXksVSgu74%3D&md5=f24a454015dead681575f8ad352062a8CAS |

Kissel DE, Sonon LS, Cabrera ML (2012) Rapid measurement of soil pH buffering capacity. Soil Science Society of America Journal 76, 694–699.
Rapid measurement of soil pH buffering capacity.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XktFOht70%3D&md5=0496cfc2dbd4146a97f6a23d58a784d2CAS |

Lambie SM, Schipper LA, Balks MR, Baisden WT (2012a) Carbon leaching from undisturbed soil cores treated with dairy cow urine. Soil Research 50, 320–327.
Carbon leaching from undisturbed soil cores treated with dairy cow urine.Crossref | GoogleScholarGoogle Scholar |

Lambie SM, Schipper LA, Balks MR, Baisden WT (2012b) Solubilisation of soil carbon following treatment with cow urine under laboratory conditions. Soil Research 50, 50–57.
Solubilisation of soil carbon following treatment with cow urine under laboratory conditions.Crossref | GoogleScholarGoogle Scholar |

Loeppert RH, Inskeep WP (1996) Iron. In ‘Methods of soil analysis, Part 3: Chemical methods’. (Ed. JM Bingham) pp. 639–644. (Soil Science Society of America and American Society of Agronomy: Madison, WI)

Parfitt RL (1990) Allophane in New Zealand—a review. Australian Journal of Soil Research 28, 343–360.
Allophane in New Zealand—a review.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK3MXmsF2itQ%3D%3D&md5=8b849d222b39173624c5e7d5ba534b77CAS |

Parfitt RL, Giltrap DJ, Whitton JS (1995) Contribution of organic-matter and clay-minerals to the cation-exchange capacity of soils. Communications in Soil Science and Plant Analysis 26, 1343–1355.
Contribution of organic-matter and clay-minerals to the cation-exchange capacity of soils.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2MXlsFyqur0%3D&md5=62d38bb51619ad8bafee01d924bffe77CAS |

Saunders WMH (1965) Phosphate retention by New Zealand soils and its relationship with free sesquioxides, organic matter, and other soil properties. New Zealand Journal of Agricultural Research 8, 30–57.
Phosphate retention by New Zealand soils and its relationship with free sesquioxides, organic matter, and other soil properties.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaF2MXpsVaqsw%3D%3D&md5=7970ded3bbec82d16e3e3b38e4df1af8CAS |

Selvarajah N (1991) Field studies of ammonia volatilisation potentials of unsaturated soils fertilised with granular urea. PhD Thesis, Lincoln University, Lincoln, New Zealand.

Sherlock RR, Black AS, Smith NP (1987) Microenvironment soil pH around broadcast urea granules and its relationship to ammonia volatilization. In ‘Nitrogen cycling in temperate agricultural systems’. (Eds PE Bacon, J Evans, RR Storrier, AC Taylor) pp. 316–326. (Australian Society of Soil Science: Wagga Wagga, NSW)

Sherlock RR, Freney JR, Bacon PE, van der Weerden TJ (1995) Estimating ammonia volatilization from unsaturated urea fertilized and urine affected soils by an indirect method. Fertilizer Research 40, 197–205.
Estimating ammonia volatilization from unsaturated urea fertilized and urine affected soils by an indirect method.Crossref | GoogleScholarGoogle Scholar |

Sims JT (1996) Lime requirement. In ‘Methods of soil analysis, Part 3: Chemical methods’. (Ed. JM Bingham) pp. 491–515. (Soil Science Society of America: Madison, WI)

Soil Survey Staff (2010) ‘Keys to Soil Taxonomy.’ 11th edn (USDA-Natural Resources Conservation Service: Washington, DC)

Thomas GW (1982) Exchangeable cations. In ‘Methods of soil analysis. Part 2.’ 2nd edn. (Eds AL Page, RH Miller, DR Keeney) pp. 159–164. (Soil Science Society of America: Madison, WI)

Thomas GW, Hargrove WL (1984) The chemistry of soil acidity. In ‘Soil acidity and liming’. Agronomy Monograph 12. (Ed. F Adams) pp. 159–165. (ASA: Madison, WI)

Thompson JS, Kissel DE, Cabrera ML, Sonon LS (2010) Equilibration reaction from single addition of base to determine soil lime requirement. Soil Science Society of America Journal 74, 663–669.
Equilibration reaction from single addition of base to determine soil lime requirement.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXjtFWru7s%3D&md5=1e40d825cdb7cc68483366ef8f3354cfCAS |