Overview

The chemical methods for determining the neutralizing value (NV) (see EN 12945) and the reactivity (see EN 13971 and EN 16357) of liming materials are not always appropriate indicators for any material claimed to have a liming effect in the soil, particularly materials with a high organic matter content. The biological mineralization of organic matter contained in some products can, in the field, have an effect on pH, which cannot be quantified by the chemical methods. The two methods described in this document overcome these problems. The European Standard specifies two methods (method A and method B) of measuring the effect of the addition of any material claimed to have a liming effect on the soil, using the same basic principles. Method A measures the changes to the soil pH resulting from the addition of any material claimed to have a liming effect on a standard soil, measured over a period of one month. Method B assesses the efficiency of any material claimed to have a liming effect, using a range of defined soils and measured over a period of up to 2,5 years. These methods allow comparison of products under controlled climatic conditions but do not replace field experiments. The methods are not applicable to mineral products coarser than 6,3 mm for method A or 20 mm for method B. As part of the revision of the 2006 edition, the effective neutralization value by incubation, ENVI, was introduced as an alternative to the neutralization value NV. The document has been prepared at CEN/TC 260 "Fertilizers and lime fertilizers" (secretariat: DIN, Germany) under German project and interlaboratory test management. National mirroring took place at Working Committee NA 057-03-02 AA "Düngemittel" ("Fertilizers") at DIN Standards Committee Food and Agricultural Products (NAL).

Document: references other documents

Responsible national committee

NA 057-03-02 AA - Fertilizers  

Responsible european committee

CEN/TC 260/WG 3 - Liming materials