Using pH-dependent CEC to determine lime requirement

Abstract

Lemire, E., Taillon, K. M. and Hendershot, W. H. 2006. Using pH-dependent CEC to determine lime requirement. Can. J. Soil Sci. 86: 133-139. Controlling soil pH is important to ensure good crop yield. This study was conducted to determine whether the accuracy of the existing Shoemaker-McLean-Pratt (SMP) pH-buffer method could be improved by using the pH-dependent cation exchange capacity curve (CECpd). Soil pH, SMP and CECpd measurements were performed on 18 acid surface horizon soil samples, with textures from sandy loam to clay loam. These soils were incubated with three levels of calcium carbonate for 12 wk, after which the soil pH and the effective cation exchange capacity (CECe) were measured. The correlation coefficient (R 2 ) for the CECpd and CECe curves was 0.96. The main factor affecting the slope of the curves is the soil organic matter content. The increase of CECe in the soil was also found to be directly proportional to the amount of lime applied, regardless of the type of soil. By using the slope of the Qv versus pH curve for each soil and the relationship between CECe and lime application, we were able to determine the lime required to raise the soil pH in water to 6.5. As an alternative to the current practice of using the SMP buffer, we propose that it should be possible to estimate the pH-dependent CEC curve from measurable soil properties (e.g., organic matter) and to estimate the lime requirement as the difference in CECpd between the existing and desired pH values. Once the slope of the Qv/pH relationship has been determined or estimated for a soil, the only measurement necessary for calculating lime requirement in subsequent years would be the soil pH. The proposed method would provide lime requirement estimates while decreasing the annual cost of soil analysis. En comparant la pente du (Qv) de chaque sol à celle du pH et en utilisant le lien entre la CECe et l'application de chaux, les auteurs ont réussi à établir la quantité de chaux nécessaire pour relever le pH du sol dans l'eau à 6,5. Au lieu de la pratique habituelle qui consiste à utiliser les solutions tamponnées SMP, les auteurs proposent qu'on estime la courbe de la CEC dépendant du pH à partir des propriétés quantifiables du sol (à savoir, la concentration de matière organique), la quantité estimative de chaux requise correspondant à la différence entre le pH existant et la valeur souhaitée sur la CECpd. Une fois qu'on a établi ou estimé le rapport Qv/pH d'un sol, la seule mesure nécessaire pour déterminer la quantité de chaux requise les années subséquentes serait donc le pH du sol. Pareille méthode permettrait d'estimer les besoins en chaux tout en réduisant le coût annuel de l'analyse du sol.

Evaluating buffer methods for determining lime requirement on acidified agricultural soils of the Palouse

“…The level of correlation between a LRE using these properties is similar to that provided by the Woodruff buffer and the Sikora buffer using the WI calibration (Table 4). In some regions, using alternatives to buffer methods, base saturation (Cantarella et al., 1998), soil texture (Miller & Dellavalle, 2005), or CEC (Lemire et al., 2006) to determine LREs is common practice. The relationship between OM and soil buffering capacity is well established (Brady & Weil, 2004).…”

“…Studies in several states, including New York, Missouri, Wisconsin, and Kansas, found that these “green” buffer options successfully replace historically used buffer methods containing hazardous materials (Dietzel et al., 2009; Godsey, Pierzynski, Mengel, & Lamond, 2007; Laboski & Peters, 2005; Nathan et al., 2012). Soil properties such as BS (Cantarella et al., 1998), cation exchange capacity (CEC) (Lemire, Taillon, & Hendershot, 2006), and soil texture represented by the saturated paste test (Miller & Dellavalle, 2005) have also been used for LREs. Using these characteristics instead of a buffer reduces hazardous waste production and labor while providing alternative and potentially more effective strategies for deriving LREs than traditional buffer methods.…”

Limestone application effects on common bean (Phaseolus vulgaris L.) yield and grain iron and zinc concentration on a Ferralsol soil in Uganda

“…Similarly, Edmeades (1982) reported that effective cation exchange capacity (ECEC) increased with increasing soil pH. Lemire et al (2006) reported that CEC increased as a direct function of the amount of lime added, if the final pH of the solution remained below 7. They further reported that a 1 cmol (+) kg -1 increase in CEC for every 2.1 t ha -1 of limestone added to all soils regardless of texture, organic matter or other soil properties.…”

Evaluation of nonhazardous lime requirement estimation methods for Oregon soils

“…For example, soil pH was used in all four studies, SOM was used in three cases (Keeney & Corey, 1963;Lemire et al, 2005;McFarland et al, 2020), and KCl-extractable Al was used in two studies (McFarland et al, 2020;Miller et al, 2005). Overall, the four soil property models developed by Keeney and Corey (1963), Lemire et al (2005), and McFarland et al (2020 were shown to be acceptably accurate for estimating LR in their respective regions, based on r 2 values ranging from .71 to .88. However, each model had slightly lower r 2 values than at least one buffer method evaluated in the same study, indicating that, in general, buffer methods were more accurate for estimating lime requirement than methods based on multiple soil test properties (Keeney & Corey, 1963;Lemire et al, 2005;McFarland et al, 2020;Miller et al, 2005).…”