Division 7.1 Fate and behaviour in soilF1

All relevant information on the type and the properties of the soil used in the studies, including pH, organic carbon content, cation exchange capacity, particle size distribution and water holding capacity, at pF = 0 and pF = 2,5 has to be reported in accordance with relevant ISO or other international standards.

The microbial biomass of soils used for laboratory degradation studies must be determined just prior to the commencement and at the end of the study.

It is recommended to use as much as possible the same soils throughout all laboratory soil studies.

The soils used for degradation or mobility studies must be selected such that they are representative of the range of soils typical of the various F2regions of Great Britain where use exists or is anticipated, and be such that:

• they cover a range of organic carbon content, particle size distribution and pH values, and

• where on the basis of other information, degradation or mobility are expected to be pH dependent (e.g. solubility and hydrolysis rate — points 2.7 and 2.8), they cover the following pH ranges:

  • 4,5 to 5,5,

  • 6 to 7, and

  • 8 (approximately).

Soils used must, wherever possible, be freshly sampled. If use of stored soils is unavoidable, storage shall be properly carried out for a limited time under defined and reported conditions. Soils stored for longer periods of time can only be used for adsorption/desorption studies.

The soil chosen to begin studying shall not have extreme characteristics with respect to parameters such as particle size distribution, organic carbon content and pH.

Soils shall be collected and handled in accordance with ISO 10381-6 (Soil quality — Sampling — Guidance on the collection, handling and storage of soil for the assessment of microbial processes in the laboratory). Any deviations must be reported and justified.

Field studies shall be carried out in conditions as close to normal agricultural practice as possible on a range of soil types and climatic conditions representative of the area(s) of use. Weather conditions shall be reported in cases where field studies are conducted.