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ŠUMARSKI LIST 1-2/2015 str. 50     <-- 50 -->        PDF

Norway spruce (Picea abies (L.) H. Karst.) is one of the most important tree species in European forests, both in ecological and socio-economic terms. It is estimated that in the last 200 years, intensive spruce plantations were carried out both within and outside the species’ natural range, occasionally affecting the populations adaptability to local environmental conditions (Latalowa and Van der Knaap 2005).
In Romania, the natural altitudinal limit of Norway spruce is between 800 and 1600 m a.s.l. (Feurdean et al. 2011), but pure stands rarely descends below 1000 m a.s.l. Of the total area occupied by Norway spruce, which represents 23.3% of all Romanian forests (INS 2011), around 22% – mostly located in the Subcarpathian hills – consists of plantations established outside of the species’ natural range. In the last decades, the health status and stability of these stands at low altitude has been deteriorated.
The superior genetic value of the Romanian spruce populations has been demonstrated in a number of tests carried out across Europe, focusing mainly on the species’ bioaccumulation potential, wood quality and adaptability. The two most valuable provenances, Marginea and Moldoviţa, originate from Eastern Carpathians (Schmidt-Vogt 1977; Héois & Van de Sype 1991; Matras 1997; Skrøppa 2005; Ujvari & Ujvari 2006; Mihai 2009). Additionally, provenance Moldoviţa was nominated by International Union of Forest Research Organizations (IUFRO) as provenance of reference, in 1996.
The field trials analysed in the present paper focus on testing the genetic value of 33 seed stands selected on the basis of phenotypic criteria. Five quantitative traits were examined 30 years after planting: tree height (TH), average volume per tree (AV/T), radial increment (RI), latewood percentage (LP) and conventional wood density (CWD). The research objectives were:
(i) to assess the performances of the 33 populations under specific environmental conditions of the four trials, focusing on two groups: progeny tested in their natural range (INR) and outside their natural range (ONR), respectively;