REAKCIJA POTOMSTVA IZ SJEMENSKIH SASTOJINA OBIČNE SMREKE (Picea abies(L.) H. Karst.) TESTIRANIH U NA RAZLIČITIM STANIŠTIMA

The aim of this study was to analyse the response of 33 seed stand progenies of Norway spruce, originating from the Romanian Carpathians, in terms of growth and wood characteristics, in trials located inside (Brețcu and Gurghiu) and outside (Avrig and Câmpina) of their natural distribution. Thirty years after planting, measurements were performed for the following traits: total height (TH), average volume per tree (AV/T), radial increment (RI), latewood percentage (LP) and conventional wood density (CWD). Correlation coefficients between the evaluated traits, on one hand, and the geographical coordinates (latitude, longitude and altitude) and ecophysiological latitude of seed stands origin, on the other, were also determined. ANOVA revealed significant (P < 0.01) differences among populations for all traits, with the exception of RI, suggesting that it is possible to make a selection at the populations level. Generally, the most valuable populations for TH and RI originate from Eastern and Western Carpathians. High values for LP were recorded mainly for populations originating from Eastern Carpathians. Compared to the two trials installed inside the natural range, the values for RI, TH and AV/T diminished only in one of the two tests installed outside the natural range (Câmpina), but the value for CWD increased. This pattern of expression of traits in the two trials located outside the natural range was explained by the different climatic conditions in two areas: the thermo-pluviometric factor in May-September period (TPV-IX) is 25.3 in Avrig, and only of 21.7 in Campina trial. On the other hand, on overall and in all the Carpathians branches, for latewood proportion there was a significant decrease (P<0.001) in the two tests outside the natural range. Significant interaction (P<0.001) between population and site trial was found for RI, TH, LP and AV/T. At the same time, the traits analyzed showed low intensity correlations between their values in the four trials and geographical location (altitude, latitude, longitude and ecophysiological latitude) of seed sources origin. The IUFRO standard provenance (Moldoviţa) was one of the most valuable population for the ensemble of all trials. The results of this study allowed the identification of the best populations in each trial that can be used to establish new plantations in similar ecological conditions.Cilj istraživannja bila je analiza reakcije 33 sjemenske sastojine obične smreke, iz područja rumunjskih Karpata, s obzirom na rast i karakteristike drva na pokusnim plohama smještenim unutar (Breþcu i Gurghiu) i izvan njihove prirodne rasprostranjenosti (Avrig i Câmpina) (sl. 1). Trideset godina nakon sadnje izvršena su mjerenja sljedećih značajki: ukupna visina (UV), prosječni volumen po stablu (PV/S), radijalni prirast (RP), postotak kasnog drva (PKD) i standardna gustoća drva (SGD). Utvrđeni su i koeficijenti korelacije između ispitanih pokusnih ploha i zemljopisnih obilježja sastojina. ANOVA je otkrila značajne (P < 0.01) razlike između biljnih zajednica svih pokusnih ploha, uz iznimku radijalnog prirasta (RP), što ukazuje na činjenicu da je moguće izvršiti izbor na razini sjemenske sastojine. S obzirom na ukupnu visinu (UV) i radijalni prirast (RP), utvrđeno je da se najvrjednije sastojine općenito nalaze na istočnim i zapadnim Karpatima, iako su velike vrijednosti radijalnog prirasta (RP) i postotka kasnog drva (PKD) uglavnom zabilježene kod sastojina na istočnim Karpatima. Vrijednosti radijalnog prirasta (RP), postotka kasnog drva (PKD) (sl. 2) i prosječnog volumena po stablu (PV/S) bile su niže na pokusnim plohama smještenim izvan prirodnih staništa, dok su vrijednosti ukupne visine (UV) i standardne gustoće drva (SGD) bile više. Analiza lokacije također je pokazala veliku važnost interakcije između biljne zajednice i okoliša za sve parametre (osim SGD). Iste biološke zajednice različito reagiraju na promjene uvjeta u okolišu. Prema rezultatima ovoga rada moguće je preporučiti određene biljne zajednice, s tim da se reprodukcijski materijal iz ovih izvora može koristiti samo u ekološkim uvjetima koji su slični onima gdje je provedeno ispitivanje. Utvrđeno je da je standardna provenijencija prema IUFRO-u (Moldoviţa) najbolja biljna zajednica za provođenje svih ispitivanja.Tablica 1 prikazuje fizičko-geografske i klimatske uvjete na 4 pokusne plohe, tablica 2 prikazuje srednje vrijednosti, koeficijente varijacije i amplituda varijacije za sve analizirane parametre, u svim eksperimentima. Rezultati ANOVA-e za sve lokacije i kombinacije sve četiri lokacije prikazani su u tablici 3 i 4. Tablica 5 predstavlja rezultate Pearsonove korelacije između analiziranih parametara i zemljopisnih obilježja sastojina iz kojih dolazi sjeme

REAKCIJA POTOMSTVA IZ SJEMENSKIH SASTOJINA OBIČNE SMREKE (Picea abies(L.) H. Karst.) TESTIRANIH U NA RAZLIČITIM STANIŠTIMA

The aim of this study was to analyse the response of 33 seed stand progenies of Norway spruce, originating from the Romanian Carpathians, in terms of growth and wood characteristics, in trials located inside (Brețcu and Gurghiu) and outside (Avrig and Câmpina) of their natural distribution. Thirty years after planting, measurements were performed for the following traits: total height (TH), average volume per tree (AV/T), radial increment (RI), latewood percentage (LP) and conventional wood density (CWD). Correlation coefficients between the evaluated traits, on one hand, and the geographical coordinates (latitude, longitude and altitude) and ecophysiological latitude of seed stands origin, on the other, were also determined. ANOVA revealed significant (P < 0.01) differences among populations for all traits, with the exception of RI, suggesting that it is possible to make a selection at the populations level. Generally, the most valuable populations for TH and RI originate from Eastern and Western Carpathians. High values for LP were recorded mainly for populations originating from Eastern Carpathians. Compared to the two trials installed inside the natural range, the values for RI, TH and AV/T diminished only in one of the two tests installed outside the natural range (Câmpina), but the value for CWD increased. This pattern of expression of traits in the two trials located outside the natural range was explained by the different climatic conditions in two areas: the thermo-pluviometric factor in May-September period (TPV-IX) is 25.3 in Avrig, and only of 21.7 in Campina trial. On the other hand, on overall and in all the Carpathians branches, for latewood proportion there was a significant decrease (P<0.001) in the two tests outside the natural range. Significant interaction (P<0.001) between population and site trial was found for RI, TH, LP and AV/T. At the same time, the traits analyzed showed low intensity correlations between their values in the four trials and geographical location (altitude, latitude, longitude and ecophysiological latitude) of seed sources origin. The IUFRO standard provenance (Moldoviţa) was one of the most valuable population for the ensemble of all trials. The results of this study allowed the identification of the best populations in each trial that can be used to establish new plantations in similar ecological conditions.Cilj istraživannja bila je analiza reakcije 33 sjemenske sastojine obične smreke, iz područja rumunjskih Karpata, s obzirom na rast i karakteristike drva na pokusnim plohama smještenim unutar (Breþcu i Gurghiu) i izvan njihove prirodne rasprostranjenosti (Avrig i Câmpina) (sl. 1). Trideset godina nakon sadnje izvršena su mjerenja sljedećih značajki: ukupna visina (UV), prosječni volumen po stablu (PV/S), radijalni prirast (RP), postotak kasnog drva (PKD) i standardna gustoća drva (SGD). Utvrđeni su i koeficijenti korelacije između ispitanih pokusnih ploha i zemljopisnih obilježja sastojina. ANOVA je otkrila značajne (P < 0.01) razlike između biljnih zajednica svih pokusnih ploha, uz iznimku radijalnog prirasta (RP), što ukazuje na činjenicu da je moguće izvršiti izbor na razini sjemenske sastojine. S obzirom na ukupnu visinu (UV) i radijalni prirast (RP), utvrđeno je da se najvrjednije sastojine općenito nalaze na istočnim i zapadnim Karpatima, iako su velike vrijednosti radijalnog prirasta (RP) i postotka kasnog drva (PKD) uglavnom zabilježene kod sastojina na istočnim Karpatima. Vrijednosti radijalnog prirasta (RP), postotka kasnog drva (PKD) (sl. 2) i prosječnog volumena po stablu (PV/S) bile su niže na pokusnim plohama smještenim izvan prirodnih staništa, dok su vrijednosti ukupne visine (UV) i standardne gustoće drva (SGD) bile više. Analiza lokacije također je pokazala veliku važnost interakcije između biljne zajednice i okoliša za sve parametre (osim SGD). Iste biološke zajednice različito reagiraju na promjene uvjeta u okolišu. Prema rezultatima ovoga rada moguće je preporučiti određene biljne zajednice, s tim da se reprodukcijski materijal iz ovih izvora može koristiti samo u ekološkim uvjetima koji su slični onima gdje je provedeno ispitivanje. Utvrđeno je da je standardna provenijencija prema IUFRO-u (Moldoviţa) najbolja biljna zajednica za provođenje svih ispitivanja.Tablica 1 prikazuje fizičko-geografske i klimatske uvjete na 4 pokusne plohe, tablica 2 prikazuje srednje vrijednosti, koeficijente varijacije i amplituda varijacije za sve analizirane parametre, u svim eksperimentima. Rezultati ANOVA-e za sve lokacije i kombinacije sve četiri lokacije prikazani su u tablici 3 i 4. Tablica 5 predstavlja rezultate Pearsonove korelacije između analiziranih parametara i zemljopisnih obilježja sastojina iz kojih dolazi sjeme

The Dynamics and Variability of Radial Growth in Provenance Trials of Norway Spruce (Picea abies (L.) Karst.) Within and Beyond the Hot Margins of its Natural Range

Multi-site field trials provide valuable data for the investigation of possible effects of environmental changes on forest tree species. We analyze the descendants of plus trees from 33 Norway spruce seed sources of Romanian Carpathians, at age 30, in four comparative field trials: two established in the natural range of species and two outside of it. The dynamics and variation of radial growth, earlywood and latewood were analyzed. The influence of populations, site conditions and climatic factors were also quantified. The provenances response in the four comparative trials was asymmetric for mean radial growth, but its dynamics was less favourable outside of the natural range. Analysis of variance showed significant differences (P<0.001) between the testing sites, but non-significant (P<0.05) for the populations. Populations x localities interaction was high (P<0.001) in the first half of the testing period, but decreased over time, becoming not significant at the age of 30. At intra-populational level, the average coefficient of variation for radial growth was higher outside the natural range, whereas the proportion of latewood decreased. The temperature in the first half of the growing season negatively influenced (P<0.001) the radial increment, but in the latewood proportion significat effects (PË‚0.05) were recorded only in trials located outside of the natural range. An increased variability of radial growth and a decrease of latewood proportion are expected in Norway spruce stands located at lower altitudes, towards the limits of the natural range. Our results may contribute to the sustainable management of Norway spruce forests within and outside its natural range

The Resistance of European Beech (Fagus sylvatica) From the Eastern Natural Limit of Species to Climate Change

In this study, different approaches were used to investigate the vulnerability of beech forests, located at the eastern limit of their natural range, to climate change. To accomplish this, six 2500 m2 plots were sampled in four European beech forest genetic resources, located in Romania at different altitudinal levels, varying from 230 to 580 m in the Bacău hills and between 650 and 1300 m in the Curvature Carpathian (Braşov region). The analysis of trees phenotypic traits, their radial growth, and the regeneration, did not indicate a vulnerability of the sampled stands to the fluctuations of the environmental factors from the 1950-2014 period. The growth indices of all three populations of Bacău hills are negatively correlated with both June air temperature of current year and September of the previous year. The precipitation amount of September previous year positively influenced the growth indices. The radial growth of plots in Braşov region is slightly linked to the climate. The temperature during the growing season represents a limiting factor for stands that are located outside of the optimal altitudinal species distribution (600-1200 m, in Romania), especially at low altitudes. Our results indicated that a rise of the temperature accompanied by a possible reduction of the precipitations (as is predicted for the coming years) could increase the sensibility of beech forests at lower altitude

Identifying drivers of non-stationary climate-growth relationships of European beech

The future performance of the widely abundant European beech (Fagus sylvatica L.) across its ecological amplitude is uncertain. Although beech is considered drought-sensitive and thus negatively affected by drought events, scientific evidence indicating increasing drought vulnerability under climate change on a cross-regional scale remains elusive. While evaluating changes in climate sensitivity of secondary growth offers a promising avenue, studies from productive, closed-canopy forests suffer from knowledge gaps, especially regarding the natural variability of climate sensitivity and how it relates to radial growth as an indicator of tree vitality. Since beech is sensitive to drought, we in this study use a drought index as a climate variable to account for the combined effects of temperature and water availability and explore how the drought sensitivity of secondary growth varies temporally in dependence on growth variability, growth trends, and climatic water availability across the species’ ecological amplitude. Our results show that drought sensitivity is highly variable and non-stationary, though consis- tently higher at dry sites compared to moist sites. Increasing drought sensitivity can largely be explained by increasing climatic aridity, especially as it is exacerbated by climate change and trees’ rank progression within forest communities, as (co-)dominant trees are more sensitive to extra-canopy climatic conditions than trees embedded in understories. However, during the driest periods of the 20th century, growth showed clear signs of being decoupled from climate. This may indicate fundamental changes in system behavior and be early-warning signals of decreasing drought tolerance. The multiple significant interaction terms in our model elucidate the complexity of European beech’s drought sensitivity, which needs to be taken into consideration when assessing this species’ response to climate change.Additional authors: Isabel Dorado-Liñán, Choimaa Dulamsuren, Balázs Garamszegi, Michael Grabner, Andrew Hacket-Pain, Jon Kehlet Hansen s, Claudia Hartl, Weiwei Huang, Pavel Janda, Marko Kazimirović, Florian Knutzen, Jürgen Kreyling, Alexander Land, Nicolas Latte, François Lebourgeois, Christoph Leuschner, Luis A. Longares, Edurne Martinez del Castillo, Annette Menzel, Renzo Motta, Lena Muffler-Weigel, Paola Nola, Momchil Panayatov, Any Mary Petritan, Ion Catalin Petritan, Ionel Popa, Cǎtǎlin-Constantin Roibu , Álvaro Rubio-Cuadrado, Miloš Rydval, Tobias Scharnweber, J. Julio Camarero, Miroslav Svoboda, Elvin Toromani, Volodymyr Trotsiuk, Marieke van der Maaten-Theunissen, Ernst van der Maaten, Robert Weigel, Martin Wilmking, Tzvetan Zlatanov, Anja Rammig, Christian S. Zan

Stem and Crown Characteristics of Norway Spruce [<i>Picea abies</i> (L.) Karst] Populations from Romanian Carpathians

To establish the most important Norway spruce Romanian populations, open-pollinated progeny of ten plus trees originating from 33 seed stands mapped in the Romanian Carpathians have been evaluated for stem and crown characteristics at the age of 30 years, in two field trials: one established in their natural range (Breţcu trial), while the second was located outside of their natural range, in Subcarpathian lands (Avrig trial). Significant (p < 0.05) differences were found among the seed stands in both sites for most of the characteristics, suggesting an additive genetic control with different levels of significance depending on the evaluated trait and the testing site. Location analysis also revealed a highly significant population x locality interaction for all traits. The same populations behave differently to the change of the ecological conditions. In the Avrig trial higher values were recorded than in the Breţcu trial for the tree slenderness coefficient (19%), crown slenderness coefficient (13.6%) and crown lateral area (9.4%). Although outside of their natural area, pruning height (m) increased 6.4%, however pruning height ratio (%) decreases by 1%, compared to the test established in their natural range. The populations from the Eastern Carpathians stand out by showing sustained growth and superior wood quality, while the populations from the Western Romanian Carpathians have generally smaller differences between the mean values of analysed traits in both field trials. Qualitative characteristics that influence the stability of stands to windthrow and snowbreak showed low levels of correlations to ecological gradients of the originating location of tested seed stands

Adaptability of Narrow-Crowned Norway Spruce Ideotype (<em>Picea abies</em> (L.) Karst. <em>pendula</em> Form) in 25 Years Half-Sib Comparative Trials in the Eastern Carpathians

This study analysed the stability of the narrow-crowned Norway spruce (pendula form) compared with the classic form of spruce (pyramidalis form) in two half-sib field trials located in the Romanian Carpathians. From eight natural populations, representative of three of the four large spruce spread areas in Romania, open-pollinated seeds from 48 trees (24 pendula ideotype and 24 pyramidalis form) were collected to install the Maneciu and Soveja trials. In these trials, at age 25 years, measurements were performed for the following traits: tree height, breast height diameter, crown diameter, number of branches per whorl and dominant branch diameter. Some important traits were calculated: average volume per tree, trees’ slenderness, crown slenderness and branches’ finesse. Pearson’s simple correlations between the analysed traits were calculated and also the correlations between traits and geographic and climatic gradients of provenances’ origin. In addition, cores were collected to compare the wood density of the two forms of spruce. In both trials, but especially in the limitative environmental conditions of the Soveja trial, the narrow crowned form of Norway spruce (Picea abies f. pendula) presented more favourable average results than the normal crown spruce form for the most important stand stability traits: trees’ slenderness, wood density, branches’ diameter and branches’ finesse. Between spruce crown forms, in both trials, no significant differences were observed for the growth traits, but between trials, higher results resulted in optimal environmental conditions of the Măneciu test (+89% for the trees’ volume). The trees from different provenances and with specific forms of the crown reacted differently to the changing of the testing site, which required the adoption of maximum caution for decisions regarding the transfer of forest reproductive materials. The correlations between the analysed traits converge towards the adoption of a two-step breeding strategy, starting by selection of narrow crowned trees after stability traits

Qualitative Traits of Norway Spruce [Picea abies (L.) Karst.] Depending on First-Order Branches: Evaluation in Comparative Trials

To establish the most important Norway spruce Romanian populations in order to improve the genetic value of future forests, open-pollinated progeny of ten plus trees originating from 33 Norway spruce seed sources were evaluated at the age of 30 years in two field trials established in different site conditions: outside (Avrig trial) versus natural range (Breţcu trial) of Norway spruce in Romania. Evaluations have been made concerning the most important branches characteristics, influencing wood quality: Number of branches per whorl, dominant branch insertion angle, dominant branch diameter and branch finesse. Highly significant differences (p&lt;0.001) were found among seed sources in both sites for all of the analyzed traits. The strong populations × localities interaction show the high spruce ability to react to the changing environmental conditions. Near-sites populations were placed in the first half of ranking. Smaller values were recorded in the Avrig trial than in the Breţcu trial for the number of branches per whorl (4.5%) and branches finesse (5.1%). The populations from the Eastern Carpathians stand out by showing sustained growth and superior wood quality, while the populations from the Western Romanian Carpathians generally have smaller differences between the mean values of analysed traits in both field trials. Simultaneous improvement of the spruce following quantitative and qualitative traits pending on the number of branches per whorl and branches diameter is contraindicated. The two-stage selection strategy seems to be applicable in this case

Testing Romanian seed sources of Norway spruce (Picea abies L. Karst): results on growth traits and survival at age 30

Growth traits and survival rate were evaluated in two field trials consisting of 33 provenances (seed stands) spread across the entire natural distribution range of Norway spruce in Romania. Total tree height, diameter at breast height (DBH) and survival rate were measured at 30 years after planting. Both growth and adaptation traits show substantial genetic variation among the tested seed stands. The amplitude of variation depends markedly on trait and testing site. This fact suggests that the best performing seed stands for growth and adaptation traits at each testing site can be selected. Two groups of valuable populations, located in the North and East of Eastern Carpathians (Apuseni Mountains), were identified. Survival rate was negatively correlated with growth traits, the average values in the two field trials were 68% and 70%. By analyzing growth and adaptation traits together with stem and wood qualitative traits, the best performing populations will be considered as tested seed sources and the forest reproductive material they can provide will be recommended for use in the regions of provenance where the two field trials are located.</span

Microenvironment Impact on Survival Rate, Growth and Stability Traits, in a Half-Sib Test of Pendula and Pyramidalis Varieties of Norway Spruce

Norway spruce (Picea abies) is a tree species with low resistance to wind storms and breakage from snow. In this study, we analyzed the microenvironmental impact on the survival rate (Sr), growth, and stability traits of 25-year-old narrow (pendula)- and normal-crowned (pyramidalis) spruce varieties in the M&#259;neciu half-sib trial. The replication factor had a highly significant influence (p &lt; 0.001) on the growth and stability traits and a significant influence (p &lt; 0.05) on the Sr, which confirms the microenvironmental impact. The average Sr was 85% and was 5% higher for the pendula variety (p &lt; 0.05). For normal-crowned trees, a negative correlation (r = &minus;0.26 ***) between the crown diameter and Sr was found, while for pendula trees, the correlations were 31% lower, suggesting the pendula variety&rsquo;s high adaptation potential to a denser planting scheme. The edge effect affected the Sr of both varieties almost equally, with a 3% superiority for pendula. The Sr variations in relation to the slope position indicated that the narrow-crowned variety was less affected by the slope position, while the normal variety showed significant slope variation. The pendula variety of Norway spruce could be promoted in afforestation because of its high adaptation plasticity to a denser planting scheme