Wide Crown Research Articles

Assessment of the correlation between supracrestal gingival tissue dimensions and other periodontal phenotypes components via the digital registration method: a cross‑sectional study in a Chinese population

BackgroundSupracrestal gingival tissue dimensions (SGTDs) has been considered to be an essential element of periodontal phenotype (PP) components. This study aimed to explore the relationship between SGTDs and other PP components by digital superposition method that integrated cone beam computed tomography (CBCT) with intraoral scanning.MethodsThis cross-sectional study was conducted at the Stomatology Hospital of Fujian Medical University. Participants were recruited based on the inclusion and exclusion criteria. The data obtained from the digital scanner (TRIOS 3, 3Shape, Denmark) and CBCT images were imported into the TRIOS software (Implant Studio, 3Shape, Denmark) for computing relevant parameters. The significant level was set at 0.05.ResultsA total of 83 participants with 498 maxillary anterior teeth were finally included. The mean values of supracrestal gingival height (SGH) and the distance from the cementoenamel junction (CEJ) to the crest of the alveolar ridge (CEJ-ABC) on the buccal site were significantly higher than palatal SGH (SGH-p) and palatal CEJ-ABC (CEJ-ABC-p). Men exhibited taller CEJ-ABC and SGH-p than women. Additionally, tooth type was significantly associated with the SGH, SGH-p and CEJ-ABC-p. Taller SGH was associated with wider crown, smaller papilla height (PH), flatter gingival margin, thicker bone thickness (BT) and gingival thickness (GT) at CEJ, the alveolar bone crest (ABC), and 2 mm apical to the ABC. Smaller SGH-p displayed thicker BT and GT at CEJ, the ABC, and 2 and 4 mm apical to the ABC. Higher CEJ-ABC showed lower interproximal bone height, smaller PH, flatter gingival margin, thinner GT and BT at CEJ, and 2 mm apical to the ABC. Smaller CEJ-ABC-p displayed thicker BT at CEJ and 2 and 4 mm apical to the ABC. On the buccal, thicker GT was correlated with thicker BT at 2 and 4 mm below the ABC.ConclusionSGTDs exhibited a correlation with other PP components, especially crown shape, gingival margin and interdental PH. The relationship between SGTDs and gingival and bone phenotypes depended on the apico-coronal level evaluated.Trial registrationThis study was approved by the Biomedical Research Ethics Committee of Stomatology Hospital of Fujian Medical University (approval no. 2023-24).

Effect of Gmelina arborea (Khamhar) bund based Agroforestry system on growth performance of paddy crop

Present study describes the effect of Gmelina arborea bund based Agroforestry system on growth performance of paddy crop. An experiment was conducted on the farmer’s field in the Rudri village of Dhamtari block of Dhamtari district (C.G.) during the kharif season (July-November) of the year 2022-23. Experiment was conducted in randomized block design (RBD). The biometry of trees was studied. DBH is 20.7, 23.68, 22.62 cm and crown width 3.22, 5.2, 4.26 m. Samples were taken at the distances of 1 m, 3 m, 5 m, 7 m, and 9 m from the tree trunk and >15 m for the control. The result indicated that the Gmelina arborea bund agroforestry had a negative impact on paddy growth, which varied depending on the DBH and crown width of the tree row and distance from the tree bund. The growth of paddy, as measured by the number of hills and the number of tillers was significantly stunted by the wider crown and proximity to the tree. The number of hills and tillers were lowest between 1-3 m. from the base of tree and the highest number of hills was (14 quadrate-1) and number of tiller hill-1 were 9.58 and average shoot length was 99.33 cm, average ear length 25.29. Thus, it is concluded that Gmelina arborea trees with minimal crown width and increasing distance from the tree line had less harmful impact on the growth and production of paddy than trees with maximum crown width and close proximity to the tree or tree line.

Food tree selection by an arboreal marsupial: Implications for timber harvest

ContextThe Yellow-bellied Glider (Petaurus australis) is a vulnerable arboreal Australian marsupial that is threatened by logging. Trees used for sap feeding (sap trees) are a critical habitat requirement of the species, yet no harvest retention policy exists in the southern part of its range in Victoria, Australia. Yellow-bellied Gliders are extremely selective in sap tree use with some trees used far more frequently than others. AimsWe aimed to determine the tree species used and identify characteristics influencing intra-species tree selection for sap feeding by Yellow-bellied Gliders in the Highlands - Southern Fall Bioregion of Victoria. MethodsSap trees were located at each of 12 sites. We measured nine characteristics related to photosynthetic capability, microsite, and habitat for sap trees and the nearest tree of the same species without Yellow-bellied Glider incisions (reference tree). For sap trees, we measured 11 incision-related variables. Permutational Multivariate Analysis of Variance was conducted to identify distinguishing characteristics of sap trees. Generalised Linear Mixed Modelling was used to determine the influence of tree characteristics on abundance of incisions on a tree. Key resultsFive of 24 tree and tall shrub species present across the 12 sites were used for sap feeding. All five species were Eucalyptus. Within the tree species used, Yellow-bellied Gliders selected for trees that were larger, had wider crowns and occupied dominant and co-dominant canopy positions. ConclusionsYellow-bellied Gliders are highly selective of trees used for sap feeding. Although primarily selecting larger more dominant trees for sap feeding, lack of clear identifying characteristics means that identifying and retaining preferred sap trees in logging coupes must rely on site surveys for incisions on trees.

Control strategy of multi-stand work roll bending and shifting on the crown for UVC hot rolling mill based on MOGPR approach

In order to improve the crown control ability and high quality to meet the Profile Contour Flatness Control (PCFC) requirements of wide electrical steel in the hot strip mills (HSMs), the control strategy of multi-stand work roll bending forces and shifting stroke on the crown for the universal variable crown (UVC) mill is established based on the Multi-output Gaussian Process Regression (MOGPR) method. The UVC technology with wide crown control ability is proposed for the upstream stands, as effective and critical crown control for upstream stands, of the HSMs. The prediction model of UVC work roll shifting was developed by integrating the MOGPR method and the production process data, and it has high prediction accuracy and adaptability compared with BPNN and SVR models by using multiple evaluation indicators. The multi-stand control strategy of the UVC work roll bending forces and shifting stroke is obtained according to the shape mechanism model and the prediction model based on the MOGPR method. Compared with the conventional control strategy, it can make the most of shifting stroke and the work roll bending forces fluctuates less, of which, F1, F2, and F3 are reduced by 21.85 %, 36.15 %, and 19.67 %, respectively. The industrial application of the control strategy during rolling achieves remarkable results that the measured high precision crown hit rate of electrical steel is significantly improved in the 1450 mm HSMs.

The impact of pruning and mortality on urban tree canopy volume

Urban trees provide a wide range of ecosystem services for city residents, with tall, mature trees with wide crowns generally regarded as preferable. The tree biomass which is responsible for shading, pollution removal, rain runoff retention etc. gets periodically reduced by the municipal tree management practice of pruning. This is a necessary activity, which reduces the risk of infrastructure damage and falling branches, but many estimates of ecosystem service provision in cities do not consider its impact explicitly. Tree mortality is also higher in cities, preventing trees from attaining and remaining at large sizes. This study used extensive field measurements of tree structure to estimate the impact of pruning on 8 tree species in two Italian cities: Taranto and Florence. Crown widths were reduced by 1.6 m on average, however there is large variation between species variation with branches more often being removed for thinning crowns resulting in larger gap fractions, which increased by 15% on average. No significant differences were observed for crown widths or gap fraction between trees pruned 3 and 4 years previously, suggesting that tree crowns structurally recover from pruning after 3 years. A deterministic model revealed that current urban forest pruning rates (every 6 years) and mortality (1%) may create a situation in which a city dominated by the species studied benefits from 93.5% of the maximum ecosystem services possible. This work will allow more nuanced estimates of urban forest services to be calculated.

Evaluation of Softwood Timber Quality—A Case Study on Two Silvicultural Systems in Central Germany

Norway spruce (Picea abies (L.) H.Karst) trees planted with high stem densities produce finely branched, solid logs but are vulnerable to extreme weather events, e.g., storms. Over the last decades spruce stands have been planted at lower stand densities, resulting in wider crowns, lower crown bases, and higher stand stability, but this might decrease the quality of coniferous timber due to an increased growing rate and wider annual rings. Therefore, in this case study we investigated the influence of different silvicultural treatments and stand densities on tree morphology and wood properties of 100 spruce trees up to sawn timber as the final product. Tree morphology was assessed using mobile laser scanning. Ring width analysis, wood density measurements, and the four-point bending strength test on visually graded boards were conducted to gain information on wood properties and product quality. In stands thinned from below, higher wood densities were observed due to smaller annual rings compared to stands that were thinned from above at equal annual ring widths. In addition, crown asymmetry and the height-to-diameter ratio were identified as proxies for wood density. Lastly, visually assessed quality differences between the forest stands were discerned on the examined boards.

Role of Azadirachta indica (Neem) and Polyalthia longifolia (Asopalav) trees for improving outdoor thermal environment in unorganized urban settings

This study assesses the effect of native trees inimproving the outdoor thermal environment of an educational institute located in the semi-arid city of Ahmedabad, India. The study area was modelled using ENVI-met and validated against the field measurements. Physical properties of 8 species (55 samples) found in the city were collected. Azadirachta indica (Neem) and Polyalthia longifolia (Asopalav) are among the top 10 species found in the city. The campus has limited space availability and green cover, hence adding more trees is not possible. Hence, two separate scenarios ofonly those two specieswere developed by replacing the existing trees. The reduction in air temperature, mean radiant temperature and physiological equivalent temperature (PET) against existing scenario by Asopalav trees at a non-shaded site was found to be up to 1.0°C, 2.2°C and 2.0°C whereas by Neem trees was found to be up to 1.1°C, 2.3°C and 2.1°C. This similarity was likely due to their similar crown widths. The attenuation of direct short-wave radiation by Neem trees was more due to higher Leaf Area Density (LAD). Trees with higher LAD and wider crowns are found to be more useful in improving the outdoor thermal environment in dense urban settings with space constraints.

Assessing the contribution of seedling root traits to phosphorus responsiveness in wheat

Improving uptake efficiency of wheat is important to improving phosphorus (P) recovery and P efficiency. Different root traits have been suggested to be important to P efficiency but their relative importance has seldom been evaluated to identify which traits should be the focus for selection and breeding. This study characterized root traits of 10 varieties of wheat that differed in their responses to fertilizer P in multisite field trials with the aim to understand which traits were contributing to the variation in P efficiency. Seedlings were characterized for seminal and crown root angle, root length, root diameter, root hair length and rhizosheath volume. Experiments were conducted in two soils low in available P, and the effect of P availability on root traits was assessed by using two different rates of P in one experiment. Compared to the varieties that showed a large yield response to P in field trials, varieties with a low P response had narrow seminal roots angles, but wider crown root angles, longer root hairs, larger rhizosheath volume and higher rates of P uptake per unit root length. The importance of these traits to explain the variation in yield and yield response to P among the field trials differed but the root traits most consistently related to yield response were rhizosheath volume and root hair length. Root diameter was associated with grain yield without additional P but was not with response to P. Root angle did not contribute to yield at low P or P response.

Construction of a high-density genetic map using specific-length amplified fragment markers and identification of QTLs for branching angle in poplar.

Branching angle is a critical factor that determines the morphological establishment and is a typical quantitative trait controlled by multiple genes. In this study, we used SLAF-seq to construct a high-density genetic map, to investigate the genetic architecture of branching angle in poplar (Populus leucopyramidalis). A total of 240,672 SLAF tags were obtained, including 103,691 polymorphic SLAF tags. After filtering, 53,407 polymorphic markers were sorted into eight segregation types, and 11,162 of them were used to construct the genetic map. 8447 were on the female parent map, 8532 were on the male parent map, and 11,162 were on the integrated map. The marker coverage was 4820.84 and 5044.80cM for the female and male maps, and 3142.61cM for the integrated map. The average intervals between two adjacent mapped markers were 0.55, 0.59, and 0.28cM for the three maps, respectively. Two quantitative trait loci (QTLs) were detected. Seven markers that exceeded the threshold in these two regions were considered as being associated with branching angle and the phenotypic variance explained by each of these marker was 10.64-11.66%. After functional annotation, we identified 15 candidate genes and analyzed the expression of candidate genes in narrow and wide crown progenies by qRT-PCR. These results show that the combination of QTL and SLAF-seq will contribute to future breeding plans in poplar breeding, especially in narrow crown poplar breeding.

Differences in wood properties among Eucalyptus grandis and Eucalyptus grandis x Eucalyptus urophylla with different degrees of ploidy

We compared the anatomy, density, chemical contents, and bioenergy values of Eucalyptus grandis and hybrids of Eucalyptus grandis x Eucalyptus urophylla wood originating from diploids, triploids and tetraploids. We hypothesize that Eucalyptus grandis and hybrids of Eucalyptus grandis x Eucalyptus urophylla with different degrees of ploidy have variations as a result of different sets of chromosomes producing different phenotypic expressions and chemical constituents, such as variation in cell size and frequency, which would directly influence wood quality. Twenty-year-old trees were cut, eight for each ploidy: diploids and tetraploids are E. grandis; triploids are E. grandis x E. urophylla. We use standardized techniques. Our hypothesis was confirmed. Triploid and tetraploid trees presented wider trunks, taller trees with longer stems and wider crowns compared to diploid trees. Wood density showed significant radial variation only in diploids, while triploid and tetraploid trees were more homogeneous. In polyploid trees, the anatomical features did not clearly present a radial pattern. Triploid and tetraploid trees presented higher density wood than diploid trees. The chemical constituents varied from pith to bark in the three ploidies, but no differences between ploidies were found. For energy generation purposes, diploid and triploid trees are more desirable than tetraploid trees.

Outdoor thermal comfort enhancement using various vegetation species and materials (case study: Delgosha Garden, Iran)

Urban gardens bring various benefits including environmental, social, and cultural values to citizens around the world. Since thermally comfortable these gardens promote the quality of urban living, a plethora of studies have been conducted to extend the existing knowledge of outdoor thermal comfort. The present study intended to evaluate outdoor thermal comfort conditions in the microclimate of the urban historic garden of Urmia, Iran, for both summer and winter. Along with performing field measurements at the site based on Taghvaei's model of “Fundamental Values and Factors of Landscape (FVFL)”, a questionnaire survey was used to determine the outdoor thermal comfort range of users. Then, the ENVI-met software was used to properly simulate the factors in summer and winter. The results of the questionnaire and simulation were compared with each other and necessary solutions were presented according to previous studies to improve outdoor thermal comfort in urban spaces. The results showed that the concrete with a high-albedo, trees with wide crowns and tall trunks (Platanus and Pine), and the use of sufficient water were proposed as the optimal solution for summer. Also, asphalt with the high-albedo, Cypress, and Populus trees in winter have been considered as a suitable solution to improve the outdoors thermal comfort of Urmia city. It is expected that future studies will evaluate the effects of the results in various green urban environments and provide a practical framework for landscape architects and urban planners.

Effects of initial spacing and species mix on stand developmental patterns in two field trials in central Oregon

Productivity, stand dynamics, and ecosystem processes characterizing mixed-species forests have been inferred from a mix of inventory data, observational studies, and designed experiments. Designed experiments are expensive to implement and maintain for a sufficiently long time in most temperate species, but associated treatment replication and randomization lower the risk of confounding from spatial correlations among species composition, environmental conditions, and productivity. Results from replicated mixed-species spacing trials in 45-yr-old Pinus ponderosa/Abies grandis plots and 53-yr-old P. ponderosa/P. contorta plots demonstrated main and interaction effects of spacing and species composition on growth and stand structure, as well as the change in these effects over time. Initial spacing ranged from 1.8 m to 5.5 m on a square grid. Mixtures of P. ponderosa and A. grandis at wide spacings offered A. grandis the opportunity to achieve cumulative height growth nearly equal to P. ponderosa and thereby form a uniform mixed canopy but lower cumulative stem volume growth. The same initial species mixture at closer spacing resulted in increasingly stratified mixtures with P. ponderosa dominating the overstory due largely to its more rapid juvenile height growth and wider crown, relegating shade tolerant A. grandis to the understory. A similar pattern emerged in the mixtures of P. ponderosa and P. contorta, but with more subtle gradients in vertical structure attributable to less extreme differences in juvenile height growth and shade tolerance. By the end of 2019 (plantation age 53), no significant overyielding or underyielding occurred in the mixed-species plots of P. ponderosa/P. contorta. In contrast, by the end of 2018 the mixed-species plots of P. ponderosa/A. grandis (plantation age 45 years) achieved some overyielding that was marginally significant (net volume production) or very significant (gross volume production) only at the narrowest (1.8-m) spacing. The timing and intensity of mortality shifted mixing effects on periodic annual increment slightly over time. Evidence for consistent overyielding among spacings was weak in these P. ponderosa/P. contorta and P. ponderosa/A. grandis spacing trials at total plantation age of 53 and 45 years, respectively. However, statistical power for detecting mixing effects was limited by the relatively small number of replications, and size differentiation continues to emerge at successively wider spacings on mixed-species plots.

Ethnic uses of Parkia timoriana (Fabaceae) and their significance to the Lotha tribes of Nagaland, North east India

This work highlights the ethnic uses of Parkia timoriana and their significance for livelihoods, ecological and human health. The study was conducted through interviews and surveys in three villages of Wokha district, Nagaland, North-east India and revealed that Parkia is one of the most widely used, ethno-botanically important multipurpose tree species for the people of this region. The pods from the trees are one of the costliest vegetable in the area. Besides economic importance, its nutritional and medicinal value is highly indispensable. In addition, it also binds and prevents soil erosion from heavy rainfall through its wide crown in shifting cultivation fallows. We find that villagers are well aware of the role of Parkia from a socio-economic point of view and are establishing plantations of this species; however, their perception regarding ecological benefits is less well developed. We recommended to continue promotion of Parkia species in this region to maximize the socio-economic and ecological benefits in the future, but note the recent reports on die-back diseases that need attention for timely management interventions.

Gingival Phenotypes Amongst Male Dental Students at Kulliyyah of Dentistry, IIUM, Malaysia

The aim of the present study was to investigate the periodontal phenotypes among young Malay males with different gingival biotypes. Forty-seven systemically and periodontally healthy young Malay males participated in this study, where 25.5% were diagnosed with thin gingival biotype and 74.5% of thick biotype. The periodontal phenotypes were measured through clinical parameters presented by the gingival thickness (GT), gingival width (GW), papilla height (PH), and crown width/crown length ratio (CW/CL). Three clusters were identified through K-means cluster ing analysis based on the parameters of the periodontal phenotypes. Cluster 1 represents narrow crown form and the average CW/CL, GW, PH and PD were 0.69, 2.92, 4.55 and 2.16 mm, respectively. Cluster 2 displayed an average of 0.76, 4.29, 4.96 and 2.14 mm for CW/CL, GW, PH and PD, respectively. Cluster 3 represents wide crown form and the average displayed for CW/CL, GW, PH and PD were 0.80, 4.85, 3.73 and 2.23 mm, respectively. There were significant differences between the three clusters (p<0.05) with respect to the GW, PH and CW/CL. This study demonstrates the difference in gingival phenotypes between young Malay males. The GW has a signiϑicant positive linear correlation (p><0.05) with CW/CL and negatively correlated with PH.><0.05) with respect to the GW, PH and CW/CL. This study demonstrates the difference in gingival phenotypes between young Malay males. The GW has a significant positive linear correlation (p<0.05) with CW/CL and negatively correlated with PH.><0.05) with CW/CL and negatively correlated with PH.

Evaluation of the thermal indices and thermal comfort improvement by different vegetation species and materials in a medium-sized urban park

Regarding the significant impact of thermal comfort on users’ attendance in urban parks, there is an intense interest in studies on the outdoor thermal comfort in parks especially in regions with hot summers. This research examines the determinant factors of thermal environment and also strategies related to albedo and greenery in a medium-scale park using ENVI-met software. In this regard, the environmental situation is analyzed using air (Ta) and surface temperature (Ts), wind speed (WS), sky view factor (SVF), the mean radiant temperature (MRT), and physiological equivalent temperature (PET). Subsequently, low- and high-albedo pavements, plane and pine trees, and Buxus shrubs strategies are investigated that can significantly influence the parameters. According to the results, SVF is not a precise indicator for determining radiation exposure and thermal comfort conditions despite its wide application in previous studies. Further, there is a significant correlation between SVF and PET only during sunlight and sunset. In addition, the best thermal comfort condition can be reached by combining the low-albedo pavements, and trees with wide crowns and high trunks. The crown height from the ground is an important factor due to its effect on the airflow that can also counteract the impact of slightly increased radiation. Field investigation and simulation studies reveal that the effect of albedo on thermal comfort is lower than the vegetation coverage. Nevertheless, the significant changes in albedo values and urban heat island mitigation do not have any considerable effect on thermal comfort improvement in urban parks.

Catalpa ovata G. Don. potential medicinal value of leaves

Catalpa ovata G. Don. has a certain degree of appreciation because of its unique tree shape and wide crown. It also has certain adaptability. This experiment uses organic materials such as Fourier transform infrared (FT-IR) spectroscopy, gas chromatography-mass spectrometer (GC-MS), learning content management system, thermal desorption - GC-MS, termal gravimetric analyzer and other modern techniques to extract organic reagents from Catalpa ovata G. Don?s Leaves. The original powder was tested differently and analyzed, investigated. To explored and developed its potential medicinal value, and better understood its use in biomedicine, as well as perfumery and chemical industries, providing some research for further and in-depth research basis.

Mortality patterns after different levels of harvesting of old-growth boreal forests

Mortality is an important process to include when modelling forest stand development. Previous attempts to model mortality after partial cutting mostly focused on overturning and stem breakage. However, in old irregular and unmanaged stands, many processes may be acting at the same time, portions of the stands being at different developmental stages. In order to better understand the mortality processes in such stands, mortality after 5 years was analyzed in old-growth black spruce (Picea mariana) and balsam fir (Abies balsamea) stands subjected to a wide range of harvesting intensities. The study comprises three sites where five treatments were applied at two scales. Mixed logistic regressions explaining total mortality and its distribution across mortality types were developed. Results show that the effects of partial cutting in these stands are complex. Mortality in uncut stands was rather high and many trees died standing. Stem breakage was of minor importance, regardless of treatment. Mortality increased with DBH and harvesting intensity and was higher for balsam fir in comparison with black spruce. Mortality was influenced not only by the locally applied treatment (2500 m2) but also by the treatment applied over a larger area (10–20 ha). Critical wind speeds derived form an adaptation of the ForestGales model were not successful in explaining total mortality or mortality type, although critical wind speeds were generally lower for dead trees in comparison with living trees. The increased mortality was directly related to an increase in the relative importance of uprooting. The type of mortality was more difficult to predict than total mortality and was related to individual tree variables. Results show an influence of crown width, with overturning being more prevalent for trees with wider crowns. Our study indicates that, until there is a better understanding of the factors leading to trees that die standing, it will continue to be difficult to predict mortality in these types of stand.

Особливості розвитку крон дуба звичайного (Quercus robur L.) на клонових насінних плантаціях у Харківській області

Представлено результати досліджень розвитку крон клонів плюсових дерев дуба звичайного (Quercus robur L.) на трьох клонових насінних плантаціях (КНП) в Харківській області віком 35 і 40 років з розміщенням садивних місць 5 × 5 м та 10 × 5 м. На КНП представлені клони плюсових дерев з Харківської і Сумської областей.
 Проаналізовано результати досліджень, проведених на КНП у 1999 і 2018 рр. У процесі вивчення розвитку крон на КНП дуба звичайного у не менш, ніж у трьох рамет кожного клону, визначали висоту дерева, діаметр проекції крони та розраховували об’єм продуктивної (з погляду репродукції) частини крони. За показниками розмірів крони визначали оптимальну кількість дерев на КНП.
 Відзначено низьку та середню індивідуальну мінливість між клонами за висотою крони, середню – за діаметром проекції крони, високу і підвищену – за об’ємом репродуктивної частини крони. Визначено клони, які суттєво перевищують середні показники по КНП за висотою і діаметром проекції крони, тобто мають найкраще розвинені крони.
 Зафіксовано переваги за висотою дерев на КНП 35-річного віку за розміщення 5 × 5 м, тоді як найбільші показники діаметра крони та об’єму продуктивного шару крони відзначено на 40-річній КНП з розміщенням щеп 10 × 5 м. Виявлено, що до змикання крон у міжряддях спостерігається інтенсивніший розвиток крони у ширину, а після змикання – у висоту.
 Для покращення умов освітлення та живлення дерев і збереження наявного продуктивного шару крони доцільно з 15-20 років здійснювати селективне зрідження. Оптимальна кількість дерев має розраховуватися на основі показника середнього діаметру проекції крони. Тривала експлуатація КНП дуба звичайного є доцільною за умови здійснення своєчасних зріджувань і збереження максимальних розмірів продуктивної частини крони.

Linkages between tree architectural designs and life-history strategies in a subtropical montane moist forest

Tree architecture is crucial to maximizing light capture, determined by carbon allocation of individual trees, and consequently characterizes species-specific growth strategies. Its variation and associated life-history strategies have been examined in tropical and temperate forests, but not in subtropical forests. Moreover, a similar architectural pattern was found using a hierarchical Bayesian model in a tropical forest, which differed from most of previous studies. Here, we employed a hierarchical Bayesian model to examine tree architecture differences and associations with adult stature and light requirement among 59 subtropical co-occurring species. Architectural variations among tree species with different seed dispersal and leaf phenology types were analyzed. Most species showed similar architecture in the height of the lowest foliage-tree height relationships (F-H) and the long side of crown- tree height relationships (W1-H), but some species showed interspecific variations in tree height-stem diameter relationships (H-D) among the 59 co-occurring species in the subtropical montane forest. Trees developed deeper and larger crowns at mid-elevation compared to the tropical and temperate forests. Parameters of H-D relationship differed in leaf phenology and dispersal types, and intercepts of F-H relationship and W1-H relationship differed in leaf phenology. Large-statured species had more slender stems, and shallower and narrower crowns at small sizes, but similar crowns at large sizes. Light-demanding species showed weak correlations between architectural variables and light requirement but exhibited wide crowns at the intermediate sizes. In general, size-dependent architectural differentiation was driven mainly by adult stature and light requirement in subtropical forest. Coexistence species showed different life-history strategies in light capture, which may help provide options in forest thinning and harvesting in subtropical forest. Species-specific tree architectural models of 59 co-occurring species represent three-dimensional (3D) structure of this subtropical forest accurately, but also support for future terrestrial laser scanning (TLS) data analysis.

Allometric Relations of Sycamore Maple (Acer pseudoplatanus) and its Red Leaf Cultivar (A. pseudoplatanus“Atropurpureum”) in Street and Park Habitats of Novi Sad (Serbia, Europe)

Adaptability and allometric relations of Acer pseudoplatanus and A. pseudoplatanus “Atropurpureum” at different urban sites are investigated in this work via the diameter at breast height (dbh), tree height, and crown width measurements, which served as ordinary least-squares regression model inputs. Differences between A. pseudoplatanus and A. pseudoplatanus “Atropurpureum,” as well as intraurban variations of trees growing at different urban site categories (park and street) and location in the same urban site category with different urban morphology characteristics, were noted. The strongest allometric relations were noted for crown width/tree height and tree height/dbh. Higher uniformity and better linear model fit were obtained for A. pseudoplatanus “Atropurpureum.” Based on allometric relations with dbh as the predictor variable, trees growing in parks were shorter and had a wider crown than street trees, whereas the same tree proportions were observed in A. pseudoplatanus.