Ring tests as main parts of the quality assurance and control programme for the comparability of analytical data within the ICP Forests monitoring programme

201

Comparabilty of analytical data as a basis of possible evaluation of European deposition, soil and foliage data

Over 100 different labs are analysing water, soil and foliage samples within the monitoring program of ICP Forests. To guarantee the comparability of the analytical results between different laboratories in several countries and over time a quality assurance (QA) program is necessary with participation of all laboratories. The QA program in each laboratory should be based on three pillars: . the use of harmonized, well-defined and documented analytical methods . an internal quality control (QC) program . an external QC program coordinated by the monitoring program organizers One part of the external QC program are ring tests between all labs. The percentage of non tolerable results in ring tests can be seen as a degree of quality and comparability of results from participating labs. The change of percentage of non-tolerable results in water, soil and foliage ring tests within the last 15 years shows the development of the quality of the labs, but also the limitation due to different analytical methods. Another possibility to benchmark the comparability and quality of labs is to analyse the same standard material during the analytical routine in different labs over time. Within the German soil survey all participating labs had to analyse standard material for each parameter all 20 samples over more than 5 years. The results of these standard material measurements and of the parallel ring tests show a good comparability for most of the soil parameters but also some problematic parameters

Exceedance of critical loads and of critical limits impacts tree nutrition across Europe

201

Nathalie Derome : les 4 ronds sont allumés : Chansons parodisiaques avec Guillaume Dostaler et René Lussier

See French abstract