Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "tree density" wg kryterium: Temat

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-10 z 10
    Tytuł:
    Metoda szacowania liczby drzew w drzewostanie sosnowym z wykorzystaniem danych ALS oraz ortoobrazów
    Method of the tree number estimation in the pine stand using ALS data and true orthoimages
    Autorzy:
    Wężyk, P.
    Tompalski, P.
    de Kok, R.
    Szostak, M.
    Kukawski, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/1008999.pdf
    Data publikacji:
    2010
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    lesnictwo
    drzewostany sosnowe
    liczba drzew
    drzewa lesne
    rozmieszczenie przestrzenne
    metody badan
    lotniczy skaning laserowy
    Numeryczny Model Koron
    klasyfikacja obiektowa
    obrazy wielospektralne
    integracja danych
    number of trees
    tree density
    airborne laser scanning
    true orthoimage
    Opis:
    Paper presents a method of estimation the number of trees and their density in Scots pine (Pinus sylvestris L.) stand based on airborne laser scanning data (ALS cloud point) and pas−sive line scanner (true orthoimage RGB/NIR). The analysis was performed on selected part of a 107−year−old stand in the Milicz Forest District (Poland). On−screen digitised shapes and centroid of crowns were used as a reference data (number of trees). Different approaches were applied for automatically determine the number of trees and their positions. The first approach, called ‘GIS watershed', was based on the canopy modelling of the ALS cloud point data. The other one, called ‘OBIA', was based on segmentation and classification of the true orthoimage (CIR). The third method – ‘data fusion' – was an integrated approach of the previous methods.. Different GIS spatial analyses were used to compare the results from all ap−proaches with the reference data. The results indicate that both datasets (ALS cloud point and true orthoimage) can be used for estimation of the number of trees in old Scots pine stand.
    Źródło:
    Sylwan; 2010, 154, 11; 773-782
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Zależność wybranych cech drzewostanów od położenia nad poziomem morza na przykładzie Parku Narodowego Gór Stołowych
    Dependence of selected stand characteristics on the elevation on the example of the Stolowe Mountains National Park
    Autorzy:
    Miścicki, S.
    Szneidrowski, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/989003.pdf
    Data publikacji:
    2017
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    lesnictwo
    lasy gorskie
    Park Narodowy Gor Stolowych
    dynamika drzewostanu
    miazszosc drzew
    miazszosc drewna
    zasobnosc drzewostanu
    zageszczenie drzew
    przyrost miazszosci
    czynniki siedliska
    wysokosc nad poziomem morza
    current volume increment
    elevation zone
    forest renewal
    net changes in standing volume
    tree density
    Opis:
    The elevation is used to illustrate the differences in the structure and growth of mountain forests. The aim of the study was to determine (1) whether the characteristics used to describe the condition and structure of forest stands under protection status (volume of merchantable timber, tree density, total height of trees in the regeneration layer, volume of dead stems, current annual volume increment, volume of dead trees, periodic changes in standing volume) change at the same rate along with the elevation, and (2) whether in mountains without upper montane zone, the values of the selected characteristics of stands located in the highest elevation zone decrease at a low rate with elevation and are comparable to the stands at the same elevation in higher mountains ranges. The study was located at an elevation of 400−909 m a.s.l. in the Stołowe Mountains National Park (PNGS; SW Poland). We used data from the measurements performed in 2009 and 2014 on 358 permanent sample plots. Plots were assigned to one of five elevation zones of 100 m a.s.l. We assumed that the characteristic value decreased with the increase in the elevation, and that such change was the same for all stand characteristics. This hypothesis was verified using the ANOVA for the repeated samples. The calculations were based on standardized values of the characteristics measured on individual sample plots. The higher above sea level the plot was located, the greater share of spruce in the stand (fig. 1). The standing volume (fig. 2), trees density (fig. 3) and current annual volume increment (fig. 6) decreased with elevation, while the volume of dead stems (fig. 4) increased. The net changes in standing volume (fig. 8) were the smallest in the stands located at the lowest and at the highest zone (400−499 and 800−909 m a.s.l.). No significant relationship was found between the total height of trees in the regeneration layer (fig. 5) or the volume of dead trees in the period 2009−2014 (fig. 7) and the elevation. Individual characteristics differed in the rate of changes of their values with elevation (fig. 9). The structure of stands growing at the highest elevation was the most variable. These stands were rather a substitute for the upper montane zone forests. The rate of the observed decrease of the volume of merchantable timber, tree density and current volume increment in the stands of PNGS was higher than in other forests in the Polish mountains.
    Źródło:
    Sylwan; 2017, 161, 02; 131-141
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Określenie przy pomocy krzywej równowagi pożądanej struktury liczby drzew w lesie różnowiekowym
    Determination of the desirable tree abundance pattern in the uneven-aged forest using the equilibrium curve
    Autorzy:
    Kweczlich, I.
    Miścicki, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/1019275.pdf
    Data publikacji:
    2006
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    Roztoczanski Park Narodowy
    krzywa rownowagi
    Abies
    rezerwaty przyrody
    buk
    lesnictwo
    model rownowagi dla lasu
    Fagus
    drzewostany roznowiekowe
    rezerwat Bukowa Gora
    obliczenia
    urzadzanie lasu
    jodla
    struktura drzew
    equilibrium curve
    tree density
    forest regeneration
    strict protection
    selection forest
    fir
    beech
    bukowa góra
    roztoczański national park
    Opis:
    The theoretical tree density in a stand was calculated using an equilibrium curve model. The Bukowa Góra forest (Roztoczański National Park) placed under strict protection was the object of the study. Calculations were made separately for the main species − fir and beech. The data on tree mortality rate and their diameter growth (or height in the case of low trees) collected in 1991, 1996 and 2001 on permanent sample plots were used. The correspondence between the actual and model tree density curves in diameter classes was confirmed only in the case of firs from the upper layer of stands. The shortage of firs (in comparison with the model data) and the excess of beeches in the regeneration layer in respect of thin and moderately thick DBH were confirmed by gradual changes in tree−species composition between 1991 and 2001.
    Źródło:
    Sylwan; 2006, 150, 03; 17-30
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Wpływ wskaźnika zadrzewienia drzewostanu na wybrane cechy makrostruktury i gęstość drewna świerkowego (Picea abies (L.) Karst.)
    Effect of stand density index on selected features of macrostructure and density of Norway spruce (Picea abies (L.) Karst.) wood
    Autorzy:
    Michalec, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/978906.pdf
    Data publikacji:
    2020
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    tree−ring width
    latewood proportion
    wood density
    Norway spruce
    Opis:
    The aim of the study was to determine the influence of stand density index on the tree−ring width, latewood proportion and wood density for Norway spruce. Study sites were located as follows: 12 within the north−eastern species range in Poland, 7 in the south−western range, in the Sudety Mts., and 9 in the Carpathians (southern range). Clustering stands according to their stand density index, 10 data groups were established: stand density index values from 0.3 to 1.2. The study plots were 100×100 m squares. On each plot 15 trees were chosen and increment cores were sampled using the Pressler borer. The smoothed cores served for measuring the width of annual rings, latewood zones and the share of latewood as well as for determination of relative wood density. The performed analyses indicate that mean tree−ring width was the highest in trees from stands with density index from 0.3 to 0.8 (with the exception of 0.7), whereas the it was gradually decreasing in stands with index higher than 0.9. The statistically significant differences between the analyzed stands were observed (p<0.0001). The analysis of the influence of stand density index and the width of annual rings revealed significant, negative weak correlation (r=–0.242, p<0.001). In turn, the latewood proportion was the highest in trees from stands characterised by the highest stand density index and the lowest in trees from stands with the lowest one. The differences between analyzed groups of stands were statistically significant (p<0.0001), as well as the correlation which was significant, positive and weak (r=0.269, p<0.001). Wood density was the highest in trees from stands with the highest stand density index (1.1 – 363 kg/m3 i 1.2 – 365 kg/m3) as well as in those from stands characterised by 0.7 density index (369 kg/m3). Significant differences were observed (p<0.0001) only between stand density index 0.3−0.7 and 0.7−0.8. Significant correlation was not observed.
    Źródło:
    Sylwan; 2020, 164, 09; 719-725
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Ekologiczne konsekwencje hodowli drzew w różnym zagęszczeniu I. Wzrost i rozwój drzewostanu
    Ecological consequences of silviculture at variable stand densities. I. Stand growth and development
    Autorzy:
    Jagodziński, A.M.
    Oleksyn, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/1012013.pdf
    Data publikacji:
    2009
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    wzrost drzewostanu
    wiezba drzew
    zageszczenie poczatkowe
    drzewostany
    lesnictwo
    zageszczenie roslin
    rozwoj drzewostanu
    stand density
    spacing
    tree competition
    tree biometry
    stand growth and development
    review
    Opis:
    The main goal of this review was to characterize ecological consequences of growing trees at variable stand densities. We found that the majority of studies were focused on biometry, productivity and mortality of trees, and wood quality and its economic value, while the influence of stand density on biomass allocation, abiotic and biotic factors, chemistry of different tree organs, diversity and biomass of understory plants, ecophysiology of trees and microclimate conditions (e.g. temperature, humidity, light conditions, etc.) were only occasionally addressed. Stand growth and development trajectories are clearly modified by stand density, however the strength of influence depends on the phase of stand development. Lower seedling densities in nursery conditions lead to increases in their height and diameter, thus influencing seedling quality used in afforestation. The positive influence of higher density on diameter and height of trees in younger stages of stand development may be a result of higher probability of seedlings being planted in more favorable microhabitats, improvement of microclimate conditions, earlier crown closure that reduces interspecific competition for nutrient and water resources. Moreover, stand density clearly influences branch diameter and length, and thus knot size. Higher stand density results in earlier crown closure and higher tree mortality, leading to vertical and horizontal changes in stand structure (DBH, height and crown dimensions of trees). In the denser stands slender and flexible trees with small, narrow crowns dominate, and most of the trees belong to the 3rd class according to Kraft' classification of tree social positions in the stand. The influence of stand density on stand structure may lead to changes in biomass partitioning and thus merchantable wood production and nutrient retention in particular tree organs.
    Źródło:
    Sylwan; 2009, 153, 02; 75-85
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Aproksymacja rozkładów pierśnic drzew w dwugeneracyjnych drzewostanach za pomocą rozkładów mieszanych. III. Estymatory jądrowe a rozkłady mieszane
    Approximation of the breast height diameter distribution of two-cohort stands by mixture models. III. Kernel density estimators vs mixture models
    Autorzy:
    Podlaski, R.
    Roesch, F.A.
    Powiązania:
    https://bibliotekanauki.pl/articles/990995.pdf
    Data publikacji:
    2014
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    lesnictwo
    drzewostany dwupokoleniowe
    rozklad piersnic
    aproksymacja
    rozklad mieszany
    rozklad Weibulla
    estymatory jadrowe nieparametryczne
    two−component models
    kernel density estimator
    tree diameter distribution
    monte carlo simulation
    Opis:
    Two−component mixtures of either the Weibull distribution or the gamma distribution and the kernel density estimator were used for describing the diameter at breast height (dbh) empirical distributions of two−cohort stands. The data consisted of study plots from the Świętokrzyski National Park (central Poland) and areas close to and including the North Carolina section of the Great Smoky Mountains National Park (USA; southern Appalachians). Kernel density estimators belong to a class of nonparametric density estimators. Nonparametric estimators have no fixed structure and depend upon all the data points to reach an estimate. In this study the Weibull and the gamma mixture distributions were the most versatile models. The results also support the conclusion that there are only minor differences between the parametric models and the kernel density estimates.
    Źródło:
    Sylwan; 2014, 158, 06; 414-422
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Ekologiczne konsekwencje hodowli drzew w różnym zagęszczeniu III. Stabilność drzewostanu, fitoklimat i różnorodność biologiczna
    Ecological consequences of silviculture at variable stand densities. III. Stand stability, phytoclimate and biodiversity
    Autorzy:
    Jagodziński, A.M.
    Oleksyn, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/1011879.pdf
    Data publikacji:
    2009
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    wiezba drzew
    zageszczenie poczatkowe
    drzewostany
    roznorodnosc biologiczna
    mikroklimat
    lesnictwo
    ekologia lasu
    stabilnosc drzewostanu
    zageszczenie roslin
    stand density
    spacing
    tree competition
    forest ecology
    stand stability
    microclimate
    biodiversity
    review
    Opis:
    The main goal of this review was to characterize ecological consequences of growing trees at variable stand densities. We analyzed the influence of stand density on its mechanical and biological stability, diversity and biomass of understory plants and microclimate conditions (e.g. temperature, humidity, light, etc.). Higher stand density results in higher susceptibility to wind and snow damage, due to changes in height to diameter ratio (tree slenderness). The mechanical stability of stands may be promoted by silvicultural activities such as light thinning applied before growth stagnation. In addition, the reduction of stand density during stand development may increase biomass allocation to coarse roots that stabilize trees in the soil. High tree density may increase stand susceptibility to pathogens and insects and thus increase tree mortality. Trees growing at higher density (with higher intraspecific competition) may allocate less assimilates for defense against herbivorous insects and pathogens. The effect of tree density on stability of multi−species stands is inconclusive, since such studies were only occasionally undertaken. Since tree density influences light conditions (mainly before canopy closure), there is a negative relationship between stand density and herbaceous species diversity and biomass. Based on the published data, we summarized consequences of silviculture at different stand densities and proposed future directions of research needed to fill the gaps in current knowledge. Understanding the long−term ecological consequences of variable stand densities is essential for development of sustainable and stable forest ecosystems.
    Źródło:
    Sylwan; 2009, 153, 04; 219-230
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Ekologiczne konsekwencje hodowli drzew w różnym zagęszczeniu II. Produkcja i alokacja biomasy, retencja biogenów
    Ecological consequences of silviculture at variable stand densities. II. Biomass production and allocation, nutrient retention
    Autorzy:
    Jagodziński, A.M.
    Oleksyn, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/1011811.pdf
    Data publikacji:
    2009
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    wiezba drzew
    zageszczenie poczatkowe
    mikroelementy
    lesnictwo
    skladniki pokarmowe
    ekologia lasu
    makroelementy
    zageszczenie roslin
    dostepnosc skladnikow pokarmowych
    wymiana gazowa
    drzewostany
    biomasa
    alokacja biomasy
    stand density
    spacing
    tree competition
    forest ecology
    biomass allocation
    nutrient retention
    review
    Opis:
    The main goal of this review was to characterize ecological consequences of growing trees at variable stand densities. Increasing stand density results in rising competition among trees in their below− and above− ground parts, leads to changes in stand structure (DBH, height, crown width and length, crown ratio, tree slenderness, branch diameters and length) and thus modifies biomass partitioning and may influence stand productivity. Trees grown at higher density compete more intensely for limited resources such as space, light, water and nutrients, than in those grown at wider spacing. In general, total tree biomass accumulation is higher in more dense stands and in less dense stands a higher proportion of biomass is allocated to coarse roots. Moreover, stand density may alter foliage distribution within the crowns. For stands grown at higher tree density, leaf area index (LAI) may increase and thus influence stand productivity, however LAI is closely related to light requirements and succession status of the species. Because stand density may simultaneously modify macro− and micronutrient concentration in different tree tissues and biomass partitioning, it may lead to distinct changes in the nutrient balance of the forest ecosystem. For example, a considerable pool of stand mineral elements (including carbon) is allocated to roots that are not subjected to traditional stand management. Therefore, manipulation of stand density leading to higher biomass allocation to roots may increase carbon sequestration in forest ecosystems.
    Źródło:
    Sylwan; 2009, 153, 03; 147-157
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Jakość drewna sosny zwyczajnej (Pinus sylvestris L.) I. Charakterystyka wybranych cech i właściwości drewna wpływających na jego jakość
    Quality of Scots pine [Pinus sylvestris L.] wood. Part I. Characteristics of selected wood traits and properties affecting its quality
    Autorzy:
    Tomczak, A.
    Pazdrowski, W.
    Jelonek, T.
    Grzywiński, W.
    Powiązania:
    https://bibliotekanauki.pl/articles/1012211.pdf
    Data publikacji:
    2009
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    lesnictwo
    jakosc
    Pinus sylvestris
    drewno pozne
    drewno sosnowe
    seki
    drewno wczesne
    gestosc drewna
    drewno mlodociane
    sloje przyrostu rocznego
    sosna zwyczajna
    drzewa lesne
    wady drewna
    wood quality
    scots pine
    knots
    wood density
    tree rings
    latewood
    juvenile wood
    Opis:
    The study presents the synthetic characteristic of selected wood tissue traits and properties (knots, tree rings, the proportion of latewood, juvenile wood, wood density, dimensions of anatomical elements, cell wall structure), which play significant role in modifications of wood quality. At individual stage of the raw material–product cycle the term "quality" may be interpreted differently, but characteristics determining it remain unchanged. Quality depends on the natural traits and properties of wood.
    Źródło:
    Sylwan; 2009, 153, 06; 363-372
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Wieloletnia dynamika starodrzewów w zagospodarowanej części Puszczy Białowieskiej: gatunki ekspansywne i ustępujące
    Long-term dynamics of old-growth stands in the managed part of the Bialowieza Forest: increasing and declining tree species
    Autorzy:
    Drozdowski, S.
    Brzeziecki, B.
    Żybura, H.
    Żybura, B.
    Gawron, L.
    Buraczyk, W.
    Zajączkowski, J.
    Bolibok, L.
    Szeligowski, H.
    Bielak, K.
    Widawska, Z.
    Powiązania:
    https://bibliotekanauki.pl/articles/1008501.pdf
    Data publikacji:
    2012
    Wydawca:
    Polskie Towarzystwo Leśne
    Tematy:
    lesnictwo
    Puszcza Bialowieska
    starodrzew
    dynamika drzewostanu
    drzewa lesne
    swierk
    grab
    jesion
    olsza
    dab
    lipa
    brzoza
    klon
    sosna
    wiaz
    zageszczenie drzew
    piersnicowe pole przekroju
    piersnice drzew
    gatunki ekspansywne
    gatunki ustepujace
    stale powierzchnie obserwacyjne
    badania dlugoterminowe
    old−growth forest
    permanent plot
    long−term trend
    population density
    population dynamics
    tree species
    Opis:
    In the paper, an assessment of tree population dynamics in the old−growth stands of the managed part of the Białowieża Forest is presented. Data from five permanent sample plots with a total size of 9.3 ha and six inventories that cover the period 1949−2006, were used. Depending on the dynamic status, determined on the basis of changes in a number of individuals per hectare, basal area and quadratic mean diameter, three major groups of tree species were distinguished: 1) an increasing group, containing only hornbeam and lime; 2) a stable group, involving alder and spruce and 3) a declining group consisting of oak, ash, maple, pine, birch, elm and aspen.
    Źródło:
    Sylwan; 2012, 156, 09; 663-671
    0039-7660
    Pojawia się w:
    Sylwan
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-10 z 10

      Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies