Implementation of quality assurance procedures in the Italian programs of forest condition monitoring

In 1996 the assessment of tree condition in Italy was subjected to a Qualit y Assurance (QA) program. The QA program consisted in (i) the adoption of S tandard Operating Procedures (SOPs), the set of Measurement Quality Objecti ves (MQOs) expressed by Data Quality Limits (DQLs), (iii) a national traini ng and intercalibration course, and (iv) field checks, performed on a numbe r of areas spread over the country. In general, DQLs were achieved for a nu mber of tree condition indices. However, problems were identified with crow n transparency, the most used index in the international reports. Additiona l problems arose when considering the data quality at plot level as a resul t of the combined achievement of DQLs for the different tree condition indi ces.