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Featured Application: Afforestation of mixed spruce–pine stands more resistant to windfall at the upper altitudinal limit of Romanian forests. Swiss stone pine (Pinus cembra) is a feasible solution for increasing the resistance of future mixed spruce–pine stands to windfall at the upper altitudinal limit of Romanian forests. This study aims to analyze the adaptability of ten full-sib families in two different environmental conditions and their evolution in time for predicting forward selection. At a seedling age of 33, evaluations were carried out for survival rate (Sr), growth (diameter at breast height—Dbh, and trees' height), and branch traits, as well as for stem straightness. The high level of genetic variability, inheritance rate, and trait–trait correlations, registered in both trials, ensure the success of the breeding program. The Swiss stone pine shows a very good adaptation on high-sloping lands from the upper altitudinal limit of Romania's forests, with the cross-pollinated (CP) families registering a 28.5% better survival in the Rodna trial (34° slope) compared to the Păltiniș experiment (7° slope). The consanguineous families registered only an 11% Sr in Păltiniș, while in the Rodna trial, the Sr was four times higher (in both trials, consanguineous trees were dominated). The juvenile–adult correlations of growth traits were significant, indicating that early selection could be efficient. The forward selection of the best 10% of CP families for Dbh could be applied, ensuring a 9% to 15% genetic gain. [ABSTRACT FROM AUTHOR]

The article deals with the phytosociological analysis and habitat characterization of certain forest communities with beech and silver fir in Banat Mountains. Two plant associations were identified: Phyllitidi-Fagetum Vida (1959) 1963 which develops on calcareous bedrock and Festuco drymejae-Fagetum Morariu ex Resmeriță 1977 which grows on metamorphic substrate. The floristic composition of these woody plant communities displays varying proportions of silver fir with coverage levels of up to 40% and with a good regeneration capacity. Nevertheless, the basic structure of these forests is dominated by the European beech, which also demonstrates strong regenerative capabilities. In this context, the studied forest stands belong to submontane beech forests that can be further categorized into two types based on the geological substrate: (i) karstic beech forests on Cretaceous limestone with skeletal soil, and (ii) acidophilous beech forests on metamorphic bedrock, growing on deeper and slightly moist soils. The differences in their floristic composition are also revealed by the results of hierarchical clustering, which clearly separates the two beech stands growing on different geological substrates. The paper also provides insight into the origin and evolution of the silver fir in Banat region and in the structure of the studied forest communities. The silver fir is likely to have a secondary, anthropogenic origin in the studied area, having been planted and naturalized over the past few centuries. [ABSTRACT FROM AUTHOR]

An adaptive forest management, sustainable under the conditions of climate change, requires the identification of innovative solutions. However, the main challenge is the identification of forest resources with high adaptive potential to increase the stability of forest ecosystems. The national implementation of genetic monitoring activities through the integration of molecular genetics methods with classical methods of phenotypic, auxological, and climatic characterization can decisively contribute to the early identification of risky changes to the stability and adaptability of forest species to extreme climatic conditions, before they are observable phenotypically or at a population level. Genetic monitoring represents a genecological approach, being particularly relevant in the study of the adaptation of forest species to local environmental conditions and in the current context of climate changes. [ABSTRACT FROM AUTHOR]

Following an analysis of a newly developed database, which includes updated information on the state-owned grayish oak (Quercus pedunculiflora K. Koch) forests, a distribution map across Romania was created. The main findings show there is a total area of approximately 18,000 ha of forests indicating the presence of grayish oak, the species having at least 10% of the stand composition in 12,000 ha. All existing Quercus pedunculiflora, established as forest genetic resources or basic materials, are located in the silvosteppe area. In the current context of climate change, with trends towards aridification and silvosteppe expansion, the grayish oak becomes one of the main forest species that can be used in the restoration of ecosystems in areas with a dry climate and moisture deficit, characteristic of the silvosteppe. [ABSTRACT FROM AUTHOR]

Programs developed in national bio-monitoring networks, such as ICP-Forests, have limitations due to local micro-climatic variations that are difficult to assess. Therefore, new technologies (e.g., remote sensing) are needed to assess the state of forests at the local level, which can provide complete spatial information (wall-towall) continuously and at a fraction of the intensive field cost sampling. European Space Agency (ESA) Sentinel missions are useful for forest monitoring due to their high spatial (20 m) and temporal (6 days) resolutions. Moreover, the availability of both active (Sentinel-1) and passive (Sentinel-2) sensors can improve classical analysis methods based mainly on optical reflectance indices. Forest variables are assessed using a combination of EO (Earth-Observation) measurements (e.g., spectral reflectance, indices, radar scatter, interferometric coherence) and functional relationships calibrated and validated using field data. Changes in forest structure (caused by wind, floods, fires or logging activities) and the resulting processes can be identified and monitored by remote sensing using optical sensors, radar or LiDAR. Monitoring the development phases of forest vegetation, using optical sensors, can be done only in the first decade after the destabilizing event. Because the vegetation structure directly influences the radar signal, Synthetic Aperture Radar (SAR) sensors are more sensitive to temporal changes in forest structure than optical sensors. Unlike LiDAR sensors, data acquisition is not spatially limited, providing an ideal solution for monitoring the forest fund. To evaluate the opportunities offered by current and future SAR missions, it is necessary to use a Multistatic Polarimetric Interferometric Electromagnetic Model for Remote Sensing (MIPERS) simulation model. Analyzing the issues described above, the need for an operational monitoring program to ensure adequate detection of changes in forest ecosystems is highlighted. This involves the development of a system designed for continuous monitoring, able to detect local changes in trends with regional impact. Early warning is essential for combating biotic pests, while playing an important role in forest management. Effective monitoring of large areas can only be achieved with the help of Earth Observation (EO) technologies, especially through the use of specific remote sensing techniques. [ABSTRACT FROM AUTHOR]

The selection of narrow crown spruce phenotypes is of great interest to the Romania forestry sector, facing an increased frequency of windfalls in pure Norway spruce stands. Molecular markers are reliable screening tool for highlighting populations specific genetic characteristics. In the present investigation we used 12 nSSR markers to analyze two spruce metapopulations (Stâna de Vale and Păltiniș), where the two forms of narrow-crowned spruce (Picea abies var. pendula) and common spruce (Picea abies var. pyramidalis) are present. We observed very close values for several alleles in both metapopulations, but the separate analysis of ideotypes detected a higher number of alleles in the narrow-crowned ideotype (Picea abies var. pendula) (132 alleles) in metapopulation Stâna de Vale. The results showed higher mean of observed heterozygosity (HO) and expected heterozygosity (HE) in the Păltiniș metapopulation (HO = 0.713 and HE = 0.751), compared to the Stâna de Vale metapopulation (HO = 0.66 and HE = 0.715). The inbreeding coefficients were positive and not significantly different from zero in most cases. Genetic differentiation among populations was low (FST = 0.01182). The Bayesian clustering method highlighted a higher admixture in population Stâna de Vale, compared to Păltiniș where sub-clustering was observed between narrow and common spruce samples. The Arlequin outlier analyses conducted using a hierarchical model revealed the EATC2G05 locus, as a candidate locus (p = 0.0083). The BlastX analysis of EATC2G05 locus revealed high genetic similarity to the transposable element (MA_163458.g5035.t1) from the spruce genome. [ABSTRACT FROM AUTHOR]

A summary of achievements in the development of genomic and transcriptomic resources in forest species are presented in an international context. The first steps in the development of genomic resource in oak species of Romania are presented and national research priorities were discussed and determined. The application of Next Generation Sequencing (NGS) technologies may foster at the national level to identify valuable genotypes of tree forest species with increased productivity and adaptive capacity. In the framework of the Research Station of Simeria was implemented a fully equipped NGS laboratory for applications that are of interest to National Institute for Research and Development in Forestry "Marin Drăcea". At the national level there is an increased interest in development of genomic and transcriptomic resources for forest species that would allow to produce valuable new knowledge about molecular mechanisms involved in adaptation processes of tree species to biotic and abiotic stress factors. For the first time, at the national level have been developed genomic resources for oak species such as Quercus pedunculiflora, Q. pubescens, Q. robur, Q. petraea, Q. virgiliana, and Q. frainetto. Additionally, genomic resources have been developed for late bud flushing variety (var. tardifolia Czern.) found in Quercus pedunculiflora and Q. robur. The late bud flushing variety (var. tardifolia Czern.) in oak species is of great importance in forestry because of harder and more durable wood (Kleinschmit, 1993), as well as this variety is less affected by defoliators (Nețoiu et al., 2016). The employment of forest material from certified genetic resources can contribute towards successful restoration of degraded forest ecosystems and to foster resilience and stability of forests to global changes. [ABSTRACT FROM AUTHOR]

In this paper is presents the current situation, evolution of the last years and the steps to follow for appropriate thinning of three Norway spruce [Picea abies (L.) Karst] field trials. The analyzed trials are located both outside the spruce's natural range, at low altitudes, and in the ecological optimum of the species, in different regions of provenance from the Romanian Carpathians and in a wide range of habitat conditions. Two of the trials are 38 years of age and the third is younger, being installed in 1996. In the two trials approaching the age at which they complete the experimental test role and are to be transformed into seed sources (Avrig and Breţcu) the trees from each population were inventoried and the necessary measurements were made to determine the slenderness index (h/dbh). The result was a very pronounced instability in trial located outside of the natural distribution range of Norway spruce, at low altitudes (Avrig trial), opposite to the one recorded in the optimum distribution range of species (Breţcu trial). In the Avrig trial, the trees slenderness index recorded the value of 109 (7% higher than the 2010 value), 27% higher than the one recorded in the optimum distribution range of the species (Breţcu), where the trees slenderness index is practically the same (has increased from 85 to 86 in the last 8 years). In Romania (Barbu 2004), as a stability limit for spruce forests, the value of the slenderness index of 100 is established; beyond this value the stands have a very high vulnerability to the wind action. In a younger comparative trial (Comandău, 22 years old), the works began by artificially pruning of the trunks of all trees, up to a height of 2 m (were cut the branches already dried). It continued with the re-labelling of the trees included in the experiment, after which the traits required to determine the slenderness index (tree height and diameter at breast height) were measured. Finally, it began the operations necessary to reduce the number of stems to 251 trees that have 2-3 stems. The average slenderness index of the 760 trees is 86, which ensures a medium - high stability of the stand. In the following years, the Comandău comparative trial will perform as experimental test. Comparative trials of provenances must be permanently monitored for the purpose of timely implementation of all the work necessary to ensure easy access to them (by artificial pruning), easy identification of trial limits, replications and populations limits, extra stems extraction, cutting of the dry trees and those who have broken peaks and are dominated. Since the tinning works are not carried out on time in Romania, it is recommended to install the Norway spruce comparative trials on rarer plants design (3 x 3 m, up to 4 x 4 m), which would also reduce the competition between trees, the genetic component having a more significant influence. It is necessary to take all necessary measures to protect these trials: inclusion in the forest management planes in a protected functional category (5G), and from the start of the fructification, also to be included in the seed sources category. At the level of each provenance, the most vigorous trees will be designated as seed trees, and among them, those which belong to the most valuable populations will be declared elite trees, having priority to reproduction. [ABSTRACT FROM AUTHOR]