Expert Panel on Foliage and Forest Foliar Coordinationg Centre (FFCC)

Genf

2005

S. 50

Artikel aus einer ZeitschriftUnselbständiges Werk

200127429

The nutritional state of trees can be a key indicator for forest ecosystems. Inadequate nutrient supply may cause low tree vitality or increase adverse effects of air pollution. High concentrations of certain elements in foliar tissues are often the effect of intoxication or of high air pollution levels. The Expert Panel on Foliage has been established to develop and monitor methods of foliar analysis and to supervise laboratories in applying these methods. It collaborates closely with the Forest Foliar Coordinating Centre which was set up in 1994. The main activities of FFCC are the storage, quality control, evaluation, presentation, and publication of foliar Level I data, and the definition of general classification values. - Foliar sulphur concentrations have decreased drastically from the levels detected in late 1980 due to the decreased sulphur emissions, but no clear trend in foliar nitrogen levels can be seen. Most plots have an adequate status regarding nutrient concentrations. At a relatively large number of plots in Germany, Slovakia and the United Kingdom, high levels of nitrogen and sulphur were found. - The Expert Panel on Foliage has develped the foliar analysis part of the ICP Forests manual. - Participating countries have used the methods of the manual to follow the trends in foliar element concentrations. - Annual interlaboratory comparison tests have been implemented to ensure data quality. Results hsowed good quality for most of the participating laboratories. The main tasks for the future are: - to continue the annual interlaboratory comparison tests and to develop indicators for data quality; - to strengthen the exchange of information between participating countries and laboratories about analytical methods, measures of quality control and new possibilities for data evaluation.