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The present research was carried out in stands of Scots pine and black pine, pure or mixed with deciduous trees, installed on degraded lands from the Curvature Subcarpathian area, Romania, in a representative network of permanent research plots and followed the analysis of the structural diversity and stability indicators of these stands at different ages and in different conditions of degraded lands. The relationships between the quantitative variables with reference to the structure were established by analyzing the significance of the Pearson correlation coefficient (r) and also including datasets of slenderness indexes, which were classed into three domains of vulnerability to abiotic factors (like wind and snow). The compositional diversity of pine stands (pure or mixed with deciduous ones) is different in relation to age and is correlated with the structural diversity. The obtained correlation coefficients (r Pearson) express very strong and significant relationships between biometric parameters (h x Dbh, h x Lc%, Dc x Dbh, and Lc% x Dbh) of the structural diversity (r = 0.800–0.930), which is important for the analysis of the stability and vulnerability of pine forests. The strong correlation between the analyzed variables expresses a weak vulnerability to the action of harmful abiotic factors and the increase in the stability and resilience of the studied stands, especially of over 50 years old. In the old pine stands, the low-vulnerability domain (I < 0.80) is the best represented one, with an average of 64.01% from the total number of trees. At this age, trees with DBH > 22 cm fall into the low-vulnerability category. The explanation is that the stands were affected in their youth by the action of snow and wind, which, combined with the silvotechnical works performed, led to their compositional and structural diversification and increased stability. The young (0.8) and even-aged structure are the most vulnerable to abiotic factors due to the fact that a large number of trees are passing gradually into the higher cenotic classes.

More common than cervical cancer, cervical intraepithelial neoplasia (CIN) represents a precursor lesion of cervical carcinoma, being associated with HPV infection. Due to the bidirectional relationship between HPV and estrogen and progesterone in pregnancy, most of the published data claim that precancerous lesions remain stable or even regress during pregnancy, although several studies have indicated the tendency of HSILs to persist. It is considered that pregnancy-related cervical precancerous lesions undergo a postpartum regression, due to stimulatory effects of the immune microenvironment. Due to the rarity of publications on this subject, we aimed to offer a concise overview of and new insights into the current knowledge regarding the pathogenesis, diagnosis, and evolution of pregnancy-associated precancerous lesions, as well as their impact upon gestation and fertility. [ABSTRACT FROM AUTHOR]

Silver fir (Abies alba Mill.) is one of the most valuable and productive tree species across European mountains, that accomplish multiple economic, protective and ecologic functions. Alongside spruce (Picea abies (L.) Karst) and beech (Fagus sylvatica L.), silver fir is a characteristic species for the Romanian Carpathians. Although silver fir tree is recommended for the diversification of forests in order to increase the resistance to climate change, it is very sensitive to climatic excesses, especially those that proceed rapidly. Therefore, the aim of this study is to investigate both the environmental conditions and stand characteristics of fir from five mountain ranges of the Romanian Carpathians. The study is based on data recorded over a period of 10 years (1990–2000). As such, a total of 77,251 stands that occupy 211,954 hectares have been investigated in regard to silver fir behaviour. MATLAB scripts were used for analysing consistent data volumes as well as the impact of eight factors on the silver fir productivity (altitude, field aspect, field slope, soil type, participation percentage, road distance, structure and consistency). Our analysis has revealed that higher silver fir productivity is found at altitudes of up to 1200 m, on mid and upper slopes, on NW field aspects, on eutric cambisols and dystric cambisols, with a 10–20% participation in stand composition and in relatively-even aged stands with a full consistency. This study offers valuable insights for forest managers that require comprehensive information in adopting effective strategies to enhance forest resilience under climate change.

Copyright of Revista de Silvicultură şi Cinegetică is the property of Societatea Progresul Silvic / Forest Progress Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Forest soils belong to the major carbon sinks on Earth because of their high organic matter content. Forest soils from Europe store approximately 1.5 times more carbon than trees (EC/UN-ECE 2003). As dystric cambisol (2,292,385 ha) and eutric cambisol (869,909 ha) are the most widespread forest soils in Romania, we studied 5958 dystric cambisol pedogenetic horizons and 6784 eutric cambisol pedogenetic horizons. A series of correlations was made between soil organic matter and elevation, but also with tree age and stand production class. The differences between stratified soil organic matter in terms of slope aspect categories were tested, and multiple linear regression was used to determine the influences of some relief (elevation) and stand (age) characteristics on the soil organic matter content. Overall, the soil organic matter content increased with increasing elevation. Based on all 12,742 soil samples over a period of 33 years, the soil organic matter content is influenced by elevation and tree age, especially on shaded and partially shaded slope aspects. [ABSTRACT FROM AUTHOR]

Norway spruce is one of the most important wood species in Europe. Wood from Norway spruce is used for a wide range of uses, has a big economic importance and also has competitive growth rates. The research material is based on an experimental block with four planting variants, V1-2500 saplings·ha-1; V2-3330 saplings·ha-1; V3- 5000 saplings·ha-1; V4-7510 saplings·ha-1. The research aspects were: the dynamics of the number of trees·ha-1 in the range 1977-2019; the distribution of the number of trees by diameter categories; the central diameter of the base surface; the height corresponding to the central diameter of the base surface; the basic statistics of the distributions (minimum, average, maximum, standard deviation, asymmetry, excess); quality of trees in experimental block variants. Regarding the number of trees per hectare, 43.8% of the initial number of trees (V1), 54.1% (V2), 70.5% (V3), 79.2% (V4) were eliminated. It was statistically found that in all situations the best approximation between experimental and theoretical distributions was achieved by applying the Pearson Beta distribution function. The average diameter of the variants studied varies between 19.6±6.0 cm (V4) and 22.1±6.3 cm (V1 and V2) and the average height ranges from 23.5±3.5 m (V4) to 25.2±2.7 m (V1). Population variability in relation to height is generally low for all variants studied, indicated by a range of coefficient of variation between 10.7% (V1) and 15.0% (V4). As for the relative length of the crown (%), it has values specific to the planting variant analyzed. Thus, its value is between 28.5% (V4) and 32.5% (V1). The average of stability index characteristic of the average tree of the base area (hg/dg), for the component variants of the experimental block analyzed, indicates that all variants are highly vulnerable to the action of snow and wind (hg/dg > 100). From a qualitative point of view, trees with trunk rot (as a result of deer wounds) with a frequency between 13% (V2) and 24% (V4) were identified, trees with operational injuries are affected at a rate of 28% (V4), 33% (V2), broken-tip trees as well as trees with trunk breaks are insignificant in terms of the occupied proportion. [ABSTRACT FROM AUTHOR]

Environmental conservation is one of the most approached issues in the world, given the sustainable management of natural resources, through specific initiatives and strategies. The research material consisted of eight representative management units included in habitat 9410 (Acidophilous forests of Picea abies in the mountain region - Vaccinio-Piceetea). Research aspects was related to: (i) the design of the permanent plots network for the conservation status evaluation of some forest habitats of community interest from the Călimani National Park; (ii) quantification of some general characteristics of the stands corresponding to the network permanent plots; (iii) basic indicators analysis for assessing conservation status: the number of trees.ha-1 and the dead wood. The obtained results showed that among of the general statistical parameters the average diameter is between 17.1 cm and 37.6 cm, the average height has values between 14.1 m and 31.0 m. The largest number of trees per hectare is 1880 and the lowest is 400. The number of dead trees in the test area is between 80 and 360. In terms of diameter distribution, the trees under study can be classified as even-aged stands, respectively relatively uneven-aged stands. Standing dead wood represents 56% of the total volume, fallen dead wood 38%, and dead wood from stumps means 6% of the total volume considered. All standing dead wood is in decomposition class 1. Decomposition classes 4 and 5 are predominant in felled dead wood. Most of the dead wood from stumps is in decomposition class 5. Status conservation monitoring of forest habitats is a necessary activity because a nationally designed system must be as effective as possible and generate the necessary and desired results in the current international forestry circumstances. [ABSTRACT FROM AUTHOR]

The surface of degraded agricultural lands continues to increase under the influence of climatic changes. Pines have been the most frequent forest species used for afforestation in the past (period 1950-1990). The present paper presents data regarding the current state, biometric and auxologic characteristics of pine stands which emphasize the bioproductive and ecologic potential. The productivity and production were analyzed in the pine stands formed by main species such as European black pine and Scots pine, pure or mixed. The wood production (m3ha-1) recorded in pine stands is different, being based on the degradation form, phytoclimatic layer and age. As such, the volume of stands with European black pine varies between 258.89 and 512.66 m3ha-1, while for the stands with Scots pine, the values varies between 206.75 and 418.04 m3ha-1. For both species, it was obtained an semnificative correlation coefficient (R2>0.8) between diameter class (D) and unit volume (v). In the forest steppe of hill (Ss), on strongly fragmented landslides, the European black pine has proved better growth than Scots pine. In the hill zone (FD3), similar growth conditions for both species were obtained. [ABSTRACT FROM AUTHOR]

The stability and productivity of trees and stands are fundamental elements of the Norway spruce ecosystems. In order to assess the stability of the Norway spruce trees affected by trunk rot, 84 trees were investigated in three permanent experimental plots, installed in stands under the risk of biotic and abiotic factors. Research aspects were related to: (i) the speed of sound through the trunk rot wood on standing trees; (ii) the stability of trees affected by trunk rot (texture of stands affected by trunk rot in relation to the decrease of the individual stability of trees, assessing the stability of trees affected by trunk rot). The results showed the sound propagation speed in the tree trunk rot has had values between 269 m·s-1 and 826 m·s-1. In Norway spruce stands affected by trunk rot, variograms specific to individual stability have indicated a direct correlation between the frequency of injuries caused by cervids (trees with trunk rot) and reduced group stability due to the low presence to absence of maximum stability centers, which are characteristic of healthy trees. The wind resistance of Norway spruce trees, indicated by the ARBOTOM device, was find to decrease with increasing rate of decay in tree cross section. This relationship is described by a polynomial regression equation of the type y = ax² + bx + cx (y represents the proportion by which the wind resistance indicated by ARBOTOM is reduced, x – the proportion occupied by decay in the cross-section). Based on the results obtained, it can be stated that non-destructive techniques, such as those based on the concept of 'tree tomography' (acoustic scanners), can be used successfully to determine changes from inside the tree trunk, with the account that the images presented provide information on the speed of sound propagation through wood and the decrease of stability only at the level analyzed. [ABSTRACT FROM AUTHOR]

Knowing the Norway spruce stands dynamics of under the management intensity influence through the long-term experimental plots has a multitude effects, from scientific point of view, to substantiate decisions in various areas of activity specific to the environment. The research was carried out in three long-term experimental plots in which were placed, three variants of silvicultural work (control, moderate, forte) to reveal the influence of thinning on biometric characteristics and to the development of even Norway spruce stands. This paper reveal specific research aspects, as follows: (i) number of trees·ha-1; (ii) distribution of the number of trees by diameter categories; (iii) the DBH; (iv) the height corresponding to the DBH; (v) the quality of the trees in the experimental plot variants; (vi) basic distribution statistics (average, standard deviation, minimum, maximum, asymmetry, excess). In the Norway spruce stands studied, the effect of the silvicultural works on the DBH, applied in the strong variant, compared to the control variant (where no silvicultural works were performed), is manifested by its superiority, with values between 4% and 13%. The superiority of the height corresponding to the DBH, applied in the strong variant, compared to the control variant, is manifested with values between 1% and 11%. From the point of view of the distribution of the number of trees by diameter categories, the theoretical Beta distribution best achieves the adjustment of the experimental distribution. In the control variants, the influence of snow and wind are the same effect with the moderate and strong interventions of silvicultural works in the plot variants. The Norway spruce trees quality indicates that trunk rot is present in a proportion between 1% and 7% of the trees number. The damages caused by the logging process (a factor favoring the appearance of root rot) affected a number of trees between 9% and 49%. The dynamics of some structural parameters in Norway spruce stands under the influence of the silvicultural works showed the effect on the tree’s development as well as the complexity of the factors to be taken into account to establish the most efficient methods and models for Norway spruce stand management in risk areas. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Silvicultură şi Cinegetică is the property of Societatea Progresul Silvic / Forest Progress Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of the present research consisted in the comparative analysis of the resistance of the common (pyramidalis variety) and narrow crown (pendula form) spruce, on the standing trees, using the resistograph. The field works were carried out within the population Coșna, administered by forest district Dorna Candrenilor and located in the production unit III Coșna, plots 388A, B, which occupies an area of 20.5 ha. Within the stand, 40 Norway spruce trees with narrow crown were identified, 20 of them being materialized in the field. The 10 narrow-crown spruce trees chosen for testing drilling resistance belong to the pendula form, cover the population surface relatively uniform and relate to several categories of diameters. From the category of normal crown, spruce trees were also chosen 10 trees from the vicinity of the pendula trees, with similar diameters. Testing of the torsion resistance was performed at a height of 1.30 m, using the IML RESI F500-S resistograph. Analysis of the standing trees wood resistance indicates the superiority of the narrow crown spruce trees, the average amplitude indicated by the resistograph being 5.2% higher compared to the normal form, a statistically significant difference (p = 0.014). The upper strength of the narrow-crown spruce was also recorded on 5 cm fragments (except of the first fragment, nearest to the bark). This fact, in conjunction with other recent investigations, allows us to recommend the promotion of this form of Norway spruce in the afforestation works. [ABSTRACT FROM AUTHOR]

The quality assessment of the Norway spruce trees by non-destructive methods and techniques is necessary in the forestry field for the tree degradation and quality estimation. The research material consisted of two permanent experimental plots installed in Norway spruce stands, in a representative area in terms of the action of biotic and abiotic factors on wood quality. To assess the quality of Norway spruce trees through non-destructive methods and techniques, 398 trees were investigated. There have been approached researches on the frequency of the trees with root rot, the resistance to micro-drilling of the wood with decay and the density of rotting wood. The results obtained showed that in some Norway spruce stands the frequency of the trees with root rot identified with Rotfinder device has significant values (16%). Also, trees with trunk rot caused by deer wounds, affect quality timber and decrease stand stability. The relationship between the value indicated by the Rotfinder device and the proportion occupied by root rot in the Norway spruce trees cross section is given by a logarithmic equation. The average density for Norway spruce wood with rot, obtained by current research, is 0.365 (0.351 is the value for root rot and 0.375 for trunk rot). The resistance value of the micro-drilling wood rot, increases as the density of the wood increase according to an exponential equation. The results obtained are a practical importance because estimations can be made for different forest areas of the root rot proportion in cross-section area. Also, expeditious and accurate wood quality estimates can be made according to the resistance value indicated by the Resistograph device. [ABSTRACT FROM AUTHOR]

Recent studies have given more emphasis to mixed stands, highlighting the importance of species diversity, their growth and development are an important subject of research, given the advantages of the functions and services offered. The research material consisted of three representative experimental plots installed in mixed stands of Norway spruce, Silver fir and European beech. Researched aspects related to stand density, species proportion, stand composition, horizontal spatial model, vertical model, dimensional parameters distribution in the stands, and the homogeneity of the stands were addressed. The density of the Norway spruce, Silver fir and European beech mixed stands shows that the number of trees·ha-1 range between 336 and 760, the basal area·ha-1 between 38.5 m2 and 41.2 m2 and the volume·ha-1 between 570.0 m3 and 651.4 m3. Horizontal spatial tree pattern is an important attribute of the stands structure that provides an idea of the variation of tree spacing and has a direct ecological influence in many processes in forest ecosystems. The vertical structure of the mixed stands is directly related to the main processes in the dynamics of the tree, being closely related to the capacity of the adaptation of ecosystems against abiotic disturbing factors. The distribution of dimensional parameters in a stand can be understood as a property that detaches from the data of individuals, therefore, represents an intermediate scale between the tree and the stand. The use of uni-modal statistical distributions when attempting to apply distribution patterns to characterize the distribution of the number of trees by diameters can lead to simplistic descriptions, altering the characterization of the stand structure. In the Norway spruce, fir and European beech mixed stands, the high degree of structural heterogeneity is highlighted. The results obtained showed that mixed Norway spruce, fir and European beech stands can develop in a fundamentally different way, the regeneration mode as well as the different growth characteristics of the component species having a significant influence. [ABSTRACT FROM AUTHOR]

Productivity of forest ecosystems can be assessed by two categories of methods based on earth characteristics or plant-based characteristics. The research material, in present paper, consist of ten permanent experimental plots installed in representative mixed forests of Norway spruce, Silver fir and European beech, in the northern Carpathians, aged 75 to 125 years. Research issues related to some productivity indices, i.e. net primary productivity (average increase of main production), height corresponding to a reference diameter, dominant height, Eichhorn's rule were addressed. The results obtained showed that the average increase of the main production varies between 5 m3an-1ha-1 and 10 m3an-1ha-1. As the age of the stands (x) increases, the average of the main production (y) decreases, according to a power regression equation of y = axb. The relation between the species proportion involved in the mixture (by volume) (x) and the average increase of the main production of the species (y) is given also by a power regression equation of y = axb. The height corresponding to the reference diameter of 50 cm shows average values over 33 m for the analyzed species (MO, BR, FA) and the corresponding diameter of 25 cm has average values greater than 22 m. In researched mixtures from the north of the Eastern Carpathians the dominant height for the Norway spruce species varies between 37 m and 48 m, for the Silver fir tree between 37 m and 50 m and for the European beech species between 28 m and 38 m. The relation between the height (x) and the volume corresponding to the species, respectively the total volume (y) (Eichhorn rule), in analyzed mixtures, is given by an exponential regression of the form y = aexb. [ABSTRACT FROM AUTHOR]