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Tytuł:
Zmiany składu gatunkowego i struktury drzewostanów w Roztoczańskim Parku Narodowym w okresie 2007-2017
Changes in the species composition and structure of forest stands in the Roztocze National Park in the years 2007-2017
Autorzy:
Łukaszewicz, J.
Zajączkowski, G.
Gil, W.
Tittenbrun, A.
Radliński, B.
Powiązania:
https://bibliotekanauki.pl/articles/979113.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
forest dynamics
species composition
dbh distribution
permanent plot
strict protection
Opis:
The aim of the study is to analyze changes in the species composition and in the diameter structure of the main forest−building species in the Roztocze National Park (central−eastern Poland). The research was carried out on 315 permanent monitoring plots. The range of collected data included: type of protection (strict and active protection), forest site type, tree species and their dbh (>7 cm over bark). Measurements and observations were made in 2007 and repeated in 2017. There was a significant reduction in the number of all tree species, except of beech Fagus sylvatica, regardless the protection status. Despite this, the basal area for the strict and active protection zone was similar both in 2007 (37.77 and 36.39 m2/ha, respectively) and 2017 (37.17 and 37.85 m2/ha, respectively). In the whole park, the number of large trees (mainly beeches) with high individual basal area increased, while the number of young generations of all species decreased. In the strict protection zone, the admixture species (decrease by 27.3%), as well as hornbeam Carpinus betulus (decrease by 22.8%), are not particularly competitive with beech. A similar tendency, although mitigated by active silvicultural treatments, was also observed in the active protection zone, in which admixture species have lost 24.8% while hornbeam 16.2%. In the strict protection area, there was a significant reduction in the number of fir Abies alba (by 14%). In the active protection zone fir increased its range and basal area, and maintains its population practically unchanged. There was also a decrease in the number of young generations, as evidenced by changes in the frequency in the 7−16 cm dbh class. The highest level of reduction in this class was found for pine Pinus sylvestris (by 64.8%), rare species (40.4%), hornbeam (31.2%), oak Quercus robur (26.6%), and spruce Picea abies (20.5%). Only beech increased the abundance in this class (by 1.4%) as well as in the next 17−26 cm class (even by 14.2%). The presented significant changes in the species composition and structure of basal area of the stands in the Roztocze National Park that occurred in the 10−year period, indicate a significant role of tending cuts in maintaining proper species composition, appropriate diameter structure of stands, their stability of natural richness and high level of diversity of forest ecosystems.
Źródło:
Sylwan; 2020, 164, 08; 683-694
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of growth traits and qualitative indices for selection of Scots pine (Pinus sylvestris L.) elite trees. A case study from Volyn region, western Ukraine
Autorzy:
Voitiuk, Vasyl
Andreieva, Valentyna
Kychyliuk, Oleksandr
Hetmanchuk, Anatolii
Klisz, Marcin
Mohytych, Vasyl
Powiązania:
https://bibliotekanauki.pl/articles/2041521.pdf
Data publikacji:
2020
Wydawca:
Instytut Badawczy Leśnictwa
Tematy:
tree breeding
half-sib families
progeny tests
DBH
height growth
Opis:
Since the plus trees are selected based on phenotype, it is necessary to evaluate them in progeny test. The aim of this study is an indication of selecting elite mother trees based on the results from half-sib progeny test trials. As study sites, two Scots pine half-sib progeny tests were selected. During evaluation, the progenies had reached the age of 38 and 40 years, respectively. In both progeny trials, quantitative parameters and qualitative traits of Scots pine half-sib progenies were investigated. Based on these data, complex evaluation of half-sib families was carried out. We concluded that, Scots pine progenies at the age of 38 and 40 years in fresh and moist mixed forests are characterised by acceptable quality, with the survival being 25%–33% per progeny test trial. Based on a complex evaluation of 38- and 40-year-old half-sib progenies of plus trees, we proposed to select 31% of tested plus/mother trees as candidates for elite trees. Further, the list of candidates for elite trees was created with five plus trees from the Volyn region (26% of the total tested from the region) and four plus trees from the Lviv region (40% of the total tested from the region). With age, the share of the best and undesirable trees decreases, while the proportion of intermediate trees increases in both control trees and half-sib progenies. At the age of 38 and 40 years, the proportion of fast-growing offspring was from 0% to 36%, while the declining trend that was observed in previous years was being continued. Thus, due to the declining trend in the proportion of fast-growing offspring observed at the age of 38 and 40 years, we propose to select candidate trees for an elite group not early than after 40 years of test their progenies.
Źródło:
Folia Forestalia Polonica. Series A . Forestry; 2020, 62, 3; 199-209
0071-6677
Pojawia się w:
Folia Forestalia Polonica. Series A . Forestry
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Struktura lasów przerębowych w wybranych regionach orograficznych Słowacji
The structure of selection stands in selected orographic regions of Slovakia
Autorzy:
Saniga, M.
Powiązania:
https://bibliotekanauki.pl/articles/1016923.pdf
Data publikacji:
2007
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
Beskidy Orawskie
lesnictwo
Tatry Niskie
Beskidy Kysudzkie
struktura drzewostanu
drzewostany przerebowe
zasobnosc drzewostanu
Slowacja
budowa drzewostanu
selection−managed stand
optimum standing volume
de liocourt's dbh− distribution
target dbh
forests
managed for timber production
protection forests
natural regeneration
Opis:
The structure and productive potential of selection−managed stands in Slovakia are very differentiated. They depend first of all on species composition and soil conditions. On the basis of recent research, including the present study, three groups of selection stands have been distinguished on the basis of their productive potential. Spruce stands managed under selection system with an optimum standing volume of 300−350 m3/hectare and target breast height diameter of 60 cm occur on poor soils (rankers) performing mainly protective functions. The spruce and spruce−fir stands managed under selection system with an optimum standing volume of over 450 m3/hectares and target dbh of 60−70 cm are typical for most of the selection stands in Slovakia. The multi−species selection stands with dominant fir, and fir stands with an optimum volume of 450 m3/hectares and target dbh of 74 cm are characteristic for the orographic Volovské vrchy region.
Źródło:
Sylwan; 2007, 151, 10; 54-66
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wzory empiryczne do określania pierśnicowych liczb kształtu dla modrzewia
Empirical equations for the determination of dbh form factors for larch
Autorzy:
Bruchwald, A.
Dmyterko, E.
Wojtan, R.
Powiązania:
https://bibliotekanauki.pl/articles/1009106.pdf
Data publikacji:
2010
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
dendrometria
drzewa lesne
modrzew
Larix
piersnicowa liczba ksztaltu
wzory empiryczne
dbh form factors
empirical equations
larch (larix)
Opis:
The paper presents empirical equations for the determination of dbh form factors for larch. The developed equations enable the calculation of the under−bark and over−bark stem volume, merchantable tree volume and utility timber volume. The equation variants proposed in the paper enable the determination of the discussed form factors both for trees and stands.
Źródło:
Sylwan; 2010, 154, 10; 705-709
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Przyrost wartości drzewa jako kryterium regulacji cięć w rębniach złożonych
Tree value increment as a cutting control criterion in complex cutting systems
Autorzy:
Paluch, J.
Powiązania:
https://bibliotekanauki.pl/articles/1018656.pdf
Data publikacji:
2006
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
regulacja ciec
kryteria
lesnictwo
rebnie zlozone
przyrost drzew
selection stand
swiss irregular shelterwood cutting system
target dbh
regulation
profitability
Opis:
Profitability of the investment related to the leaving of trees of different diameter in a stand was calculated on the basis of present value expressed in money, calculated gross land rent, anticipated end−of−period (EOP) value and knowledge of tree growth rate for an exemplary fir stand. Assuming the break−even point at 1.5% and 3%, a desirable minimum tree increment was established for which leaving of trees in a stand should be considered economically justified. The impact of the assumed level of anticipated profitability on the vertical structure and form of stands managed under the selection and Swiss irregular shelterwood cutting systems was discussed.
Źródło:
Sylwan; 2006, 150, 12; 54-63
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Struktura rozkładów pierśnic w naturalnych górnoreglowych borach świerkowych Tatr i Beskidów Zachodnich w zależności od stadiów i faz rozwojowych lasu o charakterze pierwotnym
Autorzy:
Karczmarski, J.
Powiązania:
https://bibliotekanauki.pl/articles/1022174.pdf
Data publikacji:
2005
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
Tatry
Beskidy Zachodnie
rozklad piersnic
swierk
Picea
regiel gorny
lesnictwo
struktura drzewostanu
bor swierkowy
dbh distribution
stand structure
virgin type forests
spruce
Opis:
The paper focuses on dbh distributions in the natural spruce stands at different stages and in different phases of virgin type forest development in the upper montane belt (according to developmental cycle by Korpel). The dbh distributions: normal, logarithmic−normal, Weibull and gamma that were found on 12 permanent study plots measured in 1991−1994 depended on the developmental stages and phases of the stands analysed.
Źródło:
Sylwan; 2005, 149, 03; 12-23
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ocena zgodności rozkładów empirycznych pierśnic drzewostanów dębowych starszych klas wieku z terenów Lubelszczyzny i Podkarpacia z wybranymi rozkładami teoretycznymi
Evaluation of goodness-of-fit of empirical dbh distributions of old oak stands from Lubelszczyzna and Podkarpacie regions with selected theoretical distributions
Autorzy:
Magnuszewski, M.
Tomusiak, R.
Powiązania:
https://bibliotekanauki.pl/articles/973983.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
drzewostany starsze
Lubelszczyzna
Podkarpacie
Quercus
dąb
drzewostany dębowe
leśnictwo
pierśnice drzew
rozkład teoretyczny
rozkład empiryczny
dbh distribution
goodness−of−fit
oak
Opis:
Paper presents the results of investigations on agreement of empirical diameter distributions with 35 theoretical distributions in 11 old oak stands from Lubelszczyzna and Podkarpacie regions. 23 distributions turned to fit the empirical ones the most. The most suitable to model dbh distributions were three−parameter Weibull, three−parameter log−logistic and log−normal distributions.
Źródło:
Sylwan; 2011, 155, 02; 96103
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Szerokość pasma jądrowego estymatora rozkładu pierśnic w drzewostanach olszy czarnej (Alnus glutinosa (L.) Gaertn.) z zachodniej części Kotliny Sandomierskiej
Bandwidth of kernel estimator of DBH distribution in black alder (Alnus glutinosa (L.) Gaertn.) stands from west part of the Sandomierz Basin
Autorzy:
Pogoda, P.
Ochał, W.
Orzeł, S.
Powiązania:
https://bibliotekanauki.pl/articles/985919.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
dendrometria
drzewa lesne
olsza czarna
Alnus glutinosa
piersnice drzew
rozklad piersnic
estymacja
estymatory jadrowe nieparametryczne
kernel estimator
bandwidth
dbh structure
black alder
Opis:
Set of ‘nonparametric’ methods, that don’t make a priori assumption about functional form of empirical distribution was developed as an alternative to the parametric distribution modeling. The kernel estimators are one of such methods, that can be used to describe the frequency of data representing for example DBH records. Kernel smoothing requires the choice of weighting function and bandwidth also called as smoothing parameter or window. The lack of comprehensive analysis on the applicability of particular bandwidth selection methods to model DBH structure gave an impulse to present investigation aimed at determining value and variability of smoothing parameter in black alder stands. The optimal bandwidth was obtained according to six different variants of plug−in method proposed by Altman and Léger. Presented investigations were based on DBH measurements collected in 163 managed black alder stands aged from 6 to 89 years, growing in the west part of the Sandomierz Basin (S Poland). We measured in total 22,530 black alders, from 48 to 359 in individual stand. Stands were characterized by: age, quadratic mean diameter, basal area, mean height, Reineke’s stand density index and standard deviation of DBH. Smoothing parameter was obtained by means of plug−in method with the pilot bandwidth selected by: Silverman’s rule of thumb (nrd0), Scott’s method (nrd), unbiased cross−validation (ucv), biased cross−validation (bcv), method of Sheather and Jones (sj) and one−stage method of Wand and Jones (onestage). The bandwidth was first obtained to real data, then to 100 bootstrap samples of 5, 10, 15 ... and 100 trees from each stand. Smoothing parameters were characterized by mean and variance. Relationship between values of smoothing parameter and stand characteristics was determined. Finally the influence of sample size on value and variability of bandwidth was assessed. Value and variability of smoothing parameter in black alder stands are determined by stand age, sample size and method of bandwidth choice. There is a close relationship between bandwidth and the mean height (r from 0.75 to 0.83), quadratic mean diameter (r from 0.79 to 0.88) and standard deviation of DBH (r from 0.84 to 0.93). Potentially these stand features can be used to predict smoothing parameter values. Minor changes of bandwidth for samples containing above 50 trees together with persistence of standard error give an objective grounds for defining optimal number of diameters, that are necessary to kernel estimation of DBH distribution.
Źródło:
Sylwan; 2018, 162, 05; 411-421
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Population structure and regeneration status of most abundant medicinal woody plants in Mabira Central Forest Reserve management zones
Autorzy:
Tumuhe, C.L.
Mwine, R.N.
Manana, S.
Powiązania:
https://bibliotekanauki.pl/articles/2049704.pdf
Data publikacji:
2018
Wydawca:
Fundacja na Rzecz Młodych Naukowców
Tematy:
woody plant
medicinal plant
population structure
regeneration
breast height diameter
forest reserve
Mabira Forest Reserve
management zone
dbh
central forest reserve
medicinal plants
Opis:
In the rural areas 90% of the Ugandans use plants for their medicinal uses. Communities around Mabira Central Forest Reserve (CFR) harvest plants for medicinal purposes. The increased uptake of herbal medicine is a threat to the abundance and health of medicinal trees. This research determined the species population structure and regeneration status of most abundant woody medicinal plant species in Mabira CFR. Sixty nested plots measuring 20×10 m were established adjacent to transects, 20 plots per management zone. The species sampled were identified, counted, and their diameter at breast height (dbh) taken. Their density was computed. Using the dbh classes and density data, dbh distributions were established. Using Kruskal- Wallis test we ascertained if significant differences existed in medicinal plant species densities for size classes in the 3 zones. Using linear regression we got relationship between plant density and dbh. A regression analysis of In (Ni+1) against di was made to cater for the zero values of abundance per hectare. The population had a steep negative slope, meaning that it is stable and naturally replacing itself. There was a general decline in species density with dbh. The <5 dbh size class had the biggest number of individuals per hectare in the production zone. The production zone had a high regeneration potential due to most individuals being in the smallest size class. Density had a negative linear relationship with dbh. There was a significant relationship between dbh and density of species. The tree species sampled were generally naturally regenerating.
Źródło:
Environment, Earth and Ecology; 2018, 2, 1; 6-11
2543-9774
2451-4225
Pojawia się w:
Environment, Earth and Ecology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wykorzystanie technologii naziemnego skaningu laserowego w określaniu wybranych cech drzew i drzewostanów
The application of terrestrial laser scanning for determining the selected trees and forest stand parameters
Autorzy:
Wężyk, P.
Sroga, R.
Szwed, P.
Szostak, M.
Tompalski, P.
Kozioł, K.
Powiązania:
https://bibliotekanauki.pl/articles/130874.pdf
Data publikacji:
2009
Wydawca:
Stowarzyszenie Geodetów Polskich
Tematy:
naziemny skaning laserowy
TLS
pierśnica (d)
pierśnicowe pole przekroju drzewa (g)
miąższość pnia (V)
terrestrial laser scanning
DBH
basal area
volume of tree trunk
Opis:
Rozwój technologii pozyskiwania geodanych nabrał w ostatnich latach dużego tempa co skutkuje rewolucyjnymi zmianami w wielu dziedzinach gospodarki, w tym w leśnictwie, gdzie obserwuje się wdrażanie takich rozwiązań jak naziemny skaning laserowy (Terrestrial Laser Scanning; TLS). Pomiary wybranych cech drzew takich jak: wysokość, średnica, zbieżystość i objętości (miąższość grubizny) pnia są przedmiotem badań i wdrożeń. Generowane zbiory danych (chmur punktów) TLS wymagają automatycznego procesu ich przetwarzania. Prezentowana praca dotyczy zastosowania metody TLS w inwentaryzacji lasu, tj. określaniu wybranych parametrów takich jak pole przekroju pierśnicowego drzewa (g), wysokości (h) i w efekcie miąższość pnia (V). Analizie poddano drzewostan sosnowy w Nadleśnictwie Milicz (wydzielenie 236a; wiek 105 lat). Skaning przeprowadzono z 4 stanowisk stosując skaner fazowy FARO LS 880. Dane referencyjne dla średnicy pnia pozyskano tradycyjnymi instrumentami (pierśnicomierz) oraz w oparciu o lotniczy skaning laserowy dla wysokości. Testowano szereg metod i wzorów na obliczenie miąższości grubizny pni 21 drzew, tj.: metodę brył obrotowych (3 różne zestawy par przekrojów: 1.3 /6.0; 2.0/5.0 oraz 2.0/6.0 m nad gruntem) oraz pomiar sekcyjny. Obie bazują na algorytmie określania pola przekroju wycinków pnia metodą otoczki wypukłej. Za referencję przyjęto tzw. wzór empiryczny dla sosny oraz zamiennie pomiar sekcyjny TLS (długość sekcji 0.5m). Stosowano także tradycyjną metodę bazującą na tzw. tablicach miąższości drzew stojących. Wyniki wskazują, iż miąższości uzyskane metodą sekcyjnego pomiaru TLS nie różnią się istotnie statystycznie od stosowanego w praktyce leśnej wzoru empirycznego, a wartości różnic sięgają jedynie 1.5%. W przypadku wzoru na bryły obrotowe, różnice w określaniu miąższości na poziomie powierzchni sięgają od 6.1% (przekroje z wysokości: 2.0/6.0m) do 8.4% (2.0/5.0m;) powodując jej zaniżenie. Wartości maksymalne określone na poziomie pojedynczych drzew różnią się czasem aż o 38.4% (2.0/5.0), co wskazuje na zmienność geometryczną brył pni drzew. Praca potwierdziła przydatność metody pomiaru sekcyjnego TLS oraz potrzebę dalszych prac nad opracowaniem nowych standardów i parametrów w inwentaryzacji lasu oraz konieczność stosowania zautomatyzowanych procesów przetwarzania danych.
The development of geodata acquiring technology has become very fast in recent years and leads to changes in many areas of economy, also in forestry, where new, revolutionary solutions such as terrestrial laser scanning are being implemented. Measurements of such tree characteristics, as the tree height, DBH, taper and the stem volume are subject of a number of studies. Generated sets of data (point clouds) need a chain of automatic processing. This paper describes the application of TLS in forest inventory control, i.e. in determining several parameters such as basal area (g), height (h) and finally the stem volume (V). The 105 years old pine stand in Milicz Forest District was analysed (plot no. 8). Scanning was performed from 4 stations with the use of a FARO LS 880 laser scanner. Reference data were collected using both the traditional instruments (DBH), and airborne laser scanning (h). Several methods and formulas were tested to calculate the stem volume, i.e. methods based on solid of revolution (involving 3 different pairs of cross-sections: 1.3 /6.0; 2.0/5.0 and 2.0/6.0 m above the ground), and sectional measurements. In both methods, the surface area of the crosssections was calculated using the author's algorithm (convex hulls). As the reference, the so-called empirical formula designed for pine was applied, together with volume calculated for 0.5 m sections on TLS point cloud. Traditional methods based on tables with volumes calculated for single trees were also used. The results indicate that volume measurements based on sections do not differ statistically from volumes calculated by means of the empirical formula, while the differences amount to 1.5 % only. As regards the method based on solid of revolution, the differences amount to 6.1% (cross-sections: 2.0/6.0 m, Std. dev 8.0) and 8.4% (2.0/5.0 m) causing the underestimation of the volume. Maximum values, calculated for single trees, are sometimes very high (38.4% for 2.0/5.0 m cross-sections), which indicates geometrical differences in the stem solid. The paper confirmed usability of section measurements within TLS point cloud and the need for further research on defining new standards and parameters for forest inventory control, as well as the necessity of applying automatic algorithms for data processing.
Źródło:
Archiwum Fotogrametrii, Kartografii i Teledetekcji; 2009, 19; 447-457
2083-2214
2391-9477
Pojawia się w:
Archiwum Fotogrametrii, Kartografii i Teledetekcji
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Określanie wieku młodych brzóz Betula pendula Roth rosnących na gruntach porolnych
Determining the age of young silver birch (Betula pendula Roth) trees growing on former agricultural
Autorzy:
Tkaczyk, M.
Tomusiak, R.
Powiązania:
https://bibliotekanauki.pl/articles/1318016.pdf
Data publikacji:
2013
Wydawca:
Instytut Badawczy Leśnictwa
Tematy:
grunty porolne
drzewa
brzoza brodawkowata
Betula pendula
drzewa mlode
wiek drzew
okreslanie wieku
piersnice drzew
wysokosc drzew
silver birch
age
dbh
height
former agricultural land
Opis:
In Poland, according to the law (amendment of the act of 21st May 2010) – on the provision of information on the environment and its protection, public participation in environmental protection and environmental impact assessments etc. (Official Law Journal article 08.199.1227, as amended) – the owner can cut down trees without permission, if they do not exceed the age of 10 years old. However, if an owner happens to cuts down a tree on his property without knowing the age of the tree, he is liable to prosecution under this act. The aim of this study is to verify whether there is a possibility to calculate the actual age of silver birch trees growing on former agricultural lands using features that enable age of standing trees to be identified. Using these criteria, owners would be able to calculate the age of trees on their own. The research used 183 sample trees located on three research plots. For each tree, the dbh, height and prepared samples of wood from the trees base were used to give the age of the tree. The relationship between age and dbh, as well as between the age and the height was examined. The strength of correlation was compared and the strongest was used in the proposed model. Using these correlations two types of charts were constructed to estimate the age of young birches on the basis of dbh and height.
Źródło:
Leśne Prace Badawcze; 2013, 74, 4; 357-363
1732-9442
2082-8926
Pojawia się w:
Leśne Prace Badawcze
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zależność między pierśnicą a cechami koron uzyskanymi z lotniczego skanowania laserowego
Relationship between dbh and crown characteristics derived by airborne laser scanner
Autorzy:
Zasada, M.
Stereńczak, K.
Brach, M.
Powiązania:
https://bibliotekanauki.pl/articles/973712.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lasy
skanowanie laserowe
lidar
korony drzew
pomiary
powierzchnia rzutu korony
piersnicowe pole przekroju
leśnictwo
drzewa leśne
pierśnice drzew
pierśnicowe pole przekroju
airborne laser scanning
dbh
crown parameters
Opis:
The main goal of the study was the determination of the relationship between selected crown parameters derived from automatically processed airborne laser scanning (ALS) data and tree diameter. It has been found that the best set of features for that purpose is crown projection area (CPA) as a predictor and tree basal area (BA) as dependent variable. Two algorithms of crown segmentation (‘growing’ and ‘pouring’) have been analysed. Weibull, exponential and hyperbole functions have been the best for description of the relationship between CPA and BA. The relationship between tree diameter and crown characteristics was significant, but relatively weak. This can be attributed to the fact, that the relationship can be modified by various stand characteristics. Including such variables as tree stocking and crown closure should improve the model significantly.
Źródło:
Sylwan; 2011, 155, 11; 725-735
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Rozkłady teoretyczne najlepiej aproksymujące strukturę pierśnic w drzewostanach świerkowych regla górnego w rezerwacie przyrody "Śnieżnik Kłodzki"
Theoretical distributions in approximation of breast height diameter structure in upper mountain zone Norway spruce stands in 'Snieżnik Klodzki' nature reserve
Autorzy:
Sinica, P.
Tomusiak, R.
Tkaczyk, M.
Powiązania:
https://bibliotekanauki.pl/articles/989425.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
regiel gorny
rezerwat Snieznik Klodzki
drzewostany swierkowe
swierk pospolity
Picea abies
piersnice drzew
rozklad piersnic
aproksymacja
rozklad teoretyczny
dbh distribution
stand structure
native type forests
picea abies
Opis:
The study on the structure of Norway spruce old−growth stands of original provenience in upper mountain zone was carried out in a nature reserve ‘Śnieżnik Kłodzki', located in the Lądek Zdrój Forest District (SW Poland). The fieldwork was conducted in three spruce stands located at the altitude of 1,215 and 1,235 m a.s.l. The breast height diameters (dbh) of living trees were characterized. The aim of this study is to characterize the structure of dbh of trees in spruce stands of subalpine forest. Implementation of the objective will be associated with the characteristics of empirical distributions dbh and an indication of theoretical distributions of continuous random variable best approximating the structure of dbh. The comparison of empirical dbh distributions with 36 theoretical distributions were carried out, but goodness−of−fit tests proven statistically significant compatibility with seventeen of them: beta (4−parameter), Cauchy, exponential power, folded normal, gamma (3−parameter), generalized logistic, Laplace, logistic, loglogistic, loglogistic (3−parameter), lognormal (3−parameter), noncentral chi−square, normal, smallest extreme value, triangular, Weibull and Weibull (3−parameter). The dbh distributions in upper mountain spruce stands are the best fitted with logistic distribution, and subsequently loglogistic (3−parameter), generalized logistic and Weibull (3−parameter) distributions. That four distributions can be used in individual tree growth models while generating structure dbh of trees in the stand. The knowledge of dbh structure in protected stands could be helpful in shaping spruce stand structure in planned silvicultural treatments, and shows the need for silvicultural treatments in upper mountain spruce stands.
Źródło:
Sylwan; 2016, 160, 11; 905-914
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Kształtowanie się przyrostu pierśnicy drzew w drzewostanach świerkowych masywu Skrzyczne w Beskidach Zachodnich
Formation of the dbh increment in spruce stands of the Skrzyczne massif in the Beskidy Mountains
Autorzy:
Grabczyński, S
Powiązania:
https://bibliotekanauki.pl/articles/1019595.pdf
Data publikacji:
2006
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
Beskidy Zachodnie
masyw Skrzycznego
wysokosc nad poziomem morza
przyrost piersnicy
drzewostany swierkowe
lasy gorskie
lesnictwo
piersnice drzew
spruce
beskidy zachodnie mountains
dbh increment
height a.s.l.
Opis:
In the study the formation of the dbh increment in spruce stands throughout their whole life in the Skrzyczne massif in the Beskidy Zachodnie Mountains has been presented. This increment can be illustrated by means of an exponential function according to the following formula: Zr=exp(a + b·ln(w)+c·ln2(w)), regardless of the altitude above see level at which trees grow. This altitude however has an effect on the value of function parameters.
Źródło:
Sylwan; 2006, 150, 01; 3-7
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Przestrzenny rozkład opadu cetyny oraz przyrostu pierśnicy w drzewostanach sosnowych rosnących po likwidacji ogniska reprodukcji cetyńców Tomicus piniperda (L.) i T. minor (Hart.)
Spatial pattern of insect−induced needle drop and dbh increment in pine stands before and after liquidation of sawmill and landing
Autorzy:
Borkowski, A.
Powiązania:
https://bibliotekanauki.pl/articles/1026407.pdf
Data publikacji:
2003
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
drzewostany sosnowe
rozklad przestrzenny
Tomicus minor
Tomicus piniperda
szkodniki roslin
cetyniec mniejszy
cetyniec wiekszy
lesnictwo
piersnice drzew
ekologia lasu
opad cetyny
przyrost drzew
ecology
tomicus piniperda
t. minor
dbh increment
Opis:
The studies were conducted in the years 1992−1996 and 2001−2002 in the Węgle Forest Sub−district, Zagnańsk Forest District. The aim of the studies was to compare the spatial pattern of needle drop caused by Tomicus sp. and the dbh increment in pine stands before and after the liquidation of the sawmill and timber landing. Eight zones at different distances from the sawmill were distinguished: I – edge zone, II – 100 m, III – 300 m, IV – 500 m, V – 700 m, VI – 900 m, VII – 1100 m and VIII – 2000 m (control). The needle drops were collected from each zones using under−canopy plots of 4 m². in size and drilling into trees at the dbh using a Suunto increment borer. Research results confirmed the significant effect of the reproduction centres of Tomicus sp. on the losses in tree increments. The higher significant values of the needle drop during the functioning of the timber landing were related to the lower values of the dbh increment, and with the low needle drop following the liquidation of the landing the increment values were levelled in first zones.
Źródło:
Sylwan; 2003, 147, 06; 87-92
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł

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