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•Analytical non-destructive techniques in combination with chemometrics.•Methodology for early detection of wood quality based on FTIR spectroscopy.•Influence of IR bands for ...differentiation of woody regions of coniferous species.
The early detection of wood quality by using advanced analytical non-destructive methods is an ongoing area of research and is highly interesting for the forest-based sector. The presence of core wood has negative effects on the performance of this material; hence, it is essential to identify this region as well as to define the endpoint where the region defined as transition wood begins. The purpose of this study was to apply a novel methodology for wood quality classification, based on FTIR spectroscopy, in combination with chemometrics, generating models capable of differentiating and predicting core wood, transition, and outer wood of Pinus nigra. This study also attempts to classify which specific IR bands define the chemical differentiation of woody regions. The results of the predictive models generated were satisfactory, attaining a full identification of classes with a non-linear SVM-DA model showing higher correlation coefficients than the generated linear SIMCA and PLS-DA models. SIMCA and PLS-DA were suitable for bands contrast and for categorizing the IR fingerprint in relation to the core-transition-outer regions. This study presents discriminative models generated from a non-destructive and relatively fast IR methodology with high correlation coefficients, thus improving the existing methods that are currently practiced for identifying wood quality. However, the database requires progressive calibration and adjustments to have acceptable reliability when validating the methods over time.
Heat treatment is often used to improve the dimensional stability of wood. In this study, the effects of heat treatment on physical properties and surface roughness of Camiyanı Black Pine (
Pinus ...nigra Arn. subsp.
pallasiana var.
pallasiana) wood were examined. Samples obtained from Yenice-Zonguldak Forest Enterprises, Turkey, were subjected to heat treatment at varying temperatures and for varying durations. The physical properties of heat-treated and control samples were tested, and oven-dry density, air-dry density, and swelling properties were determined. The mechanical properties of heat-treated and control samples were tested, and compression strength, and Janka-hardness were determined. A stylus method was employed to evaluate the surface characteristics of the samples. Roughness measurements by the stylus method were made in the direction perpendicular to the fiber. Four main roughness parameters, mean arithmetic deviation of profile (
R
a), mean peak-to-valley height (
R
z), root mean square roughness (
R
q), and maximum roughness (
R
y) obtained from the surface of wood were used to evaluate the effect of heat treatment on the surface characteristics of the specimens. Significant difference was determined (
p
=
0.05) between physical and technological properties, and surface roughness parameters (
R
a,
R
z,
R
y,
R
q) for three temperatures and three durations of heat treatment.
Based on the findings in this study, the results showed that density, swelling, compression strength, Janka-hardness and surface roughness values decreased with increasing treatment temperature and treatment times. Increase in temperature and duration further diminished technological strength values of the wood specimens. Camiyanı Black Pine wood could be utilized by using proper heat treatment techniques without any losses in strength values in areas where working, stability, and surface smoothness, such as in window frames, are important factors.
•Results expose differences in radial growth response to climate between subspecies of black pines growing in common garden.•Spring water deficit seems to be the main constraint on black pine radial ...growth in Northwest of Tunisia.•Differences observed attest to the interaction of the environment and genetic control of black pine diameter growth.
In the Mediterranean region, the effects of climate change on tree growth have been more and more noticeable in recent decades. Pinus nigra is one of the most common mid-elevation pine in this region and one of the species most affected by increasing dryness. In Tunisia, in order to guide species selection for future reforestation of the Khroumirie Mountains, research studies are under way to improve knowledge of black pine ecology. The effects of interannual climate variations on radial growth were compared for 19 provenances of black pine in a 51-year-old common garden experiment in Souiniet (NW Tunisia, 492m) in a humid Mediterranean bioclimate. A significant positive correlation with April precipitation and a significant negative correlation with spring temperature were noted. A cool wet spring is beneficial to growth as it affects tree water balance at the onset of the growing season; in contrast, spring drought is responsible for low annual growth. Mild January–February temperatures have a positive influence on ring width as mild winters may foster photosynthesis and promote early resumption of cambial activity. Analysis of the pointer years showed that winter snow and hail are major factors limiting growth of black pine in the studied area. Despite overall similarities in ring width to climate relationships among provenances, differences observed attest to the interaction of the environment and genetic control of black pine diameter growth.
► Germination of Spanish black pine is threatened, mainly at its altitudinal limits. ► Germination success is negatively influenced by solar radiation and air temperature. ► Stand density positively ...affects the number of germinated seeds. ► Soil scalping promotes success of germination and amount of germinated seeds. ► Germination might be improved through the use of silvicultural prescriptions.
Changes in climate may reduce the success of natural regeneration and hence require adjustments to silvicultural practices. Special attention is required for species such as Spanish black pine (
Pinus nigra Arn. ssp
salzmannii) because of impediments to achieve successful natural regeneration. Spanish black pine seed germination was studied under field conditions at a normal altitude for the species and at the upper altitude limit of its distribution in the Cuenca Mountains (southeastern Spain). The aim was to assess the effect of location, overstory density, soil treatment, sowing date and climatic characteristics on regeneration success. ANOVA results indicated a significant interaction of location by overstory density on germination rates. A logistic model containing the temperature variable
Tem
minAc
, the light radiation effect (
Rad variable) and the interaction term between soil treatment (
Soil Treat) and radiation (
Soil Treat
×
Rad) correctly predicted the germination success in 94% of cases. Moreover, two Poisson regression models (one for each experimental site) showed that the number of germinated seeds depends on stand basal area (
G), soil treatment (
Soil Treat) and sowing date (
Seed Season). Conservation management could increase initial seedling recruitment by promoting soil preparation and higher basal area levels. The populations at higher altitudes are particularly endangered due to the unfavourable environmental conditions for the development of this species, which seriously affect seed rain density and germination rates.
We report the results of descriptive and functional analyses of a representative forest and watershed in the southwestern Alps, where the Forest Service has attempted reforestation of badlands for ...erosion control since 1860, relying on the non‐native Pinus nigra ssp. nigra (Austrian black pine). One hundred twenty years after the first tree plantings, the plant communities are still early seral assemblages for the most part, with Austrian black pine occurring alone in the canopy. In contrast, most of the marly soils have physically recovered part of their total depth, with layers of fragmented and altered material equal to 50 cm, but their structure and chemical fertility is still poor. Autogenic soil restoration is proceeding however, largely engineered by earthworms (up to 49 individuals and 27 g/m2). Two dominant species are presumed keystone: Lumbricus terrestris and Octolasion cyaneum (Lumbricidae). The reestablishment of indigenous tree species is apparently not inhibited by site fertility or lack of nearby seed pools. We hypothesize that excessive stand density is responsible for the poor regeneration because it discourages the birds and rodents that control seed dissemination. Mortality of pines due to infestation by Viscum album subsp. austriacum (mistletoe) is creating large openings and should be specially managed. One hundred twenty years after the first plantings, the nineteenth‐century vision that restoration of badlands was ecologically feasible is validated, as is the strategy to establish pioneer tree species. Here Austrian black pine acts as a nurse stand and enables the return of indigenous broad‐leaved trees and a wide array of herbaceous species as well. However, our results clearly indicate that appropriate silvicultural tactics should now consist of tree thinning to promote the true restoration of native biodiversity and ecosystem functions.
Until recently, the most important factors affecting the economics and genetics of the seed crop from seed orchards were considered to be the timing and duration of flowering, variation in fertility ...and the total number of clones used to establish the seed orchards. Change in climatic conditions however is an emerging factor that could prove crucial regarding the timing of flowering and synchronization among clones and thus, the quality and quantity of seed production. The temporal and spatial variation in flowering phenology and the duration of flowering were studied in consecutive years in a
Pinus nigra Arn. seed orchard. Sixty plus trees representing the distribution of the species in Northern Greece were used to establish the seed orchard, and nineteen ramets per clone were planted in a honeycomb experimental design in order to avoid kinship. Temporal variation among clones, as well as spatial variation among ramets within clones growing at different sites of the orchard were recorded, for initiation and duration of male and female flowering. The majority of clones were synchronized in dates of flowering during the year with weather conditions close to the long-term climatic conditions, except for a limited number of clones that were precocious or late flowering. The pronounced variability in climatic conditions over the 2 years strongly affected the flowering and synchronization among clones, resulting in almost complete asynchrony during the xerothermic year, which was characterized by a prolonged mean monthly temperature increase of 2.3
°C and a water deficit of 53% in a 7-month-period (November to May). These results suggest that one of the effects of a warmer and drier climate may be the lack of flowering synchronization, as pollen shedding might be completed before female conelets reach the phase of receptivity. The restriction of male parentage to a limited number of clones severely violates the panmixia assumption and could result in fertilization failure. The projected climate change for the Mediterranean region could potentially prove detrimental for fertility and flowering synchronization of forest trees, having consequences on the quantity and genetic diversity of the seed crop in seed orchards, and the natural regeneration of forest trees in forest ecosystems due to the reduced percentage of sound seed.
The scale patterns of 6000 cones from one single tree of Pinus nigra Arn. have been examined. Apart from the main Fibonacci pattern with 8 and 13 parastichies, nine aberrant spiral patterns with ...Fibonacci-type sequences have been found. They are quite rare and occur with different frequencies. The parastichy quotient 8/13 of the prevalent pattern is very close to the golden ratio 0.618. In case of the black pine it appeared that the greater the deviation of the parastichy quotient m/n from 0.618, the rarer the pattern. Similar results obtained for the sample of 1506 cones collected from three individual trees of larch (Larix decidua Mill.) suggest a true correlation between the frequency of a pattern and the deviation of its parastichy quotient from the golden ratio.
In the present study, we investigated the genetic structure and diversity of
P.
nigra
populations in Bulgaria, using simple sequence nuclear repeats. Among-population structure was studied with ...distance and Bayesian frequency methods, assuming geometric distance and a “
non
-
admixture
” model. The “
NJ
” and “
non
-
admixture
” clusters confirm the “
mountain effect
” hypothesis of the black pine genetic structure in the study region. The analyses showed moderate among-population divergence (13.31 %; AMOVA) and evidence of genetic bottlenecks. The coalescent analyses suggest that
P. nigra
has survived for a long period (thousands of generations) under strong selection pressure and that its populations continued to be exposed to stochastic factors like climate fluctuation, forest fire and disease. The combination of recent and historic changes is responsible for the present population size and genetic diversity. Our results suggest that conservation and management practices should strive to maintain this genetic differentiation, specifically by emphasising reforestation efforts with stocks from local provenances to avoid non-local introductions.
In this study, organic matter and nutrients (N, P, K, Ca, Mg and Na) concentration were estimated at the forest floor and soil of
Pinus nigra
stands growing in the area of the Russian Monastery at ...Mount Athos and compared with three other
Pinus nigra
stands at higher altitudes in Northern Greece. Results show higher concentration of organic matter and nutrients at the forest floor of
Pinus nigra
stands on Mount Athos. Climate, low altitude and possibly the provenance of the species are the main reasons for the high accumulation of organic matter and nutrients found at the forest floor.
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