Handbook of Vitamin C Research

In: Handbook of Vitamin C Research ISBN: 978-1-60741-874-0Editors: Hubert Kucharski and Julek Zajac©2009 Nova Science Publishers, Inc.Chapter XIIVitamin C as a Stress Bioindicatorof Norway Spruce: A Case Studyin SloveniaSamar Al Sayegh Petkovšek and Boštjan PokornyERICo Velenje, Ecological Research and Industrial Cooperation, Velenje, SloveniaAbstractThe physiological condition of Norway spruce (Picea abies (L.) Karst.) andconsequently the vitality of forest ecosystems was intensively studied in the period 1991–2007 in northern Slovenia, i.e., in the area influenced by the Šoštanj Thermal PowerPlant (ŠTPP). ŠTPP, which is the largest Slovene thermal power plant, which used to bethe largest Slovene emission source of gaseous pollutants (e.g. SO 2 , NO x ) and a veryimportant source of different inorganic (e.g., heavy metals) as well as organic toxicsubstances (e.g. PAHs). However, extremely high SO 2 emission (up to 86,000 t in 1993,and > 120.000 in the 1980s, respectively) and dust emissions (up to 8,000 in 1993), havebeen dramatically reduced after the installation of desulphurization devices in the late1990s. Indeed in the comparison with 1993, SO 2 emissions in 2007 were reduced morethan 15-fold and dust emissions more than 35-fold, respectively. These extremeexposures in the past as well as huge changes in environmental pollution during the lasttwo decades have significantly influenced the vitality of forest ecosystems includingphysiological conditions (e.g., contents of antioxidant) of different tree species in thestudy area. Therefore, vitamin C (ascorbic acid) as a sensitive, non-specific bioindicatorof stress caused either by anthropogenic (e.g., air pollution) or natural stressors (climaticconditions, diseases, altitude gradient, etc.) was included in a permanent survey of forestconditions in northern Slovenia. Atmospheric pollutants such as ozone and sulphurdioxide cause formation of free radicals, which are involved in oxidation of proteins andlipids and injury of plant tissues. Plant cells have evolved a special detoxification defenceCorresponding author. Phone: +386 (0)3 898 1953; fax: +386 (0)3 898 1942; e-mail address:samar.petkovsek@erico.si