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Wyszukujesz frazę "taxonomic structure" wg kryterium: Temat


Wyświetlanie 1-7 z 7
Tytuł:
Effects of tree diversity and stand structure on above-ground carbon storage in evergreen broad-leaved and deciduous forests in Southeast Vietnam
Autorzy:
Tuan, N.T.
Rodriguez-Hernandez, D.I.
Tuan, V.C.
Quy, N.V.
Obiakara, M.C.
Hufton, J.
Powiązania:
https://bibliotekanauki.pl/articles/2130199.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
Biodiversity assessment
Ecosystem functioning
Taxonomic diversity
Natural forests
Stand structure
Opis:
Understanding the relationship between tree species diversity and above-ground carbon (AGC) storage in tropical forests is essential for a sustainable flow of ecosystem goods and services. Although tropical forests of Vietnam are of particular interest due to their high biodiversity and carbon density, few studies have evaluated the relative importance of species composition, tree species diversity and forest structure on AGC storage by forest vegetation type. In this study, we tested for the influence of taxonomic diversity, forest structure and species composition on AGC storage in evergreen broad-leaved and deciduous forests of Southeast Vietnam. Data was collected within 137 rectangular plots (25 m × 20 m), randomly selected across a deciduous forest (DF) and four evergreen broad-leaved forest (EB) categories, with different standing volumes levels: very poor (EBG), poor (EBP), medium (EBM) and rich (EBR). In total, we identified 3687 individuals from 110 tree species belonging to 46 families in 6.85 hectares of sampled area. AGC storage significantly differed among forest categories, ranging from 14.81 Mg ha−1 in EBG to 146.74 Mg ha−1 in EBR. There was higher AGC in the medium diameter class (20-40 cm), except for EBR where there was higher AGC within individuals of 40-60 cm in diameter. Taxonomic diversity was weakly correlated with AGC while stand structure (stem density and maximum diameter) were strongly correlated. Our results suggest that maintaining the abundance distributions of remnant tree species, particularly that of large trees, is one important method to enhance AGC storage in the tropical ecosytems of southern Vietnam.
Źródło:
Dendrobiology; 2022, 88; 38-55
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
GRAPH METHODS IN AN ANALYSIS OF A LEVEL AND A STRUCTURE OF PUBLIC COSTS OF UNIVERSITIES
Autorzy:
Ćwiąkała-Małys, Anna
Mościbrodzka, Monika
Powiązania:
https://bibliotekanauki.pl/articles/453021.pdf
Data publikacji:
2015
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Katedra Ekonometrii i Statystyki
Tematy:
taxonomic methods
public universities
an analysis of a level and a structure of costs
Opis:
In this article a usage of graph methods as a tool for a classification of polish public universities due to a generated level and a structure of costs is shown. The research was conducted in a spatial interpretation and referring to 57 public universities of an academic function. The usage of graph methods constitutes a tool which can be used by decision makers in a process of searching for ineffective usage of public sources. The outcomes should be a basis for further cause and effect analysis.
Źródło:
Metody Ilościowe w Badaniach Ekonomicznych; 2015, 16, 1; 85-95
2082-792X
Pojawia się w:
Metody Ilościowe w Badaniach Ekonomicznych
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Structure of organic farmings cultivations in the selected EU countries in 2004-2012
Struktura upraw rolnictwa ekologicznego wybranych krajów UE w latach 2004-2012
Autorzy:
Kukuła, K.
Strojny, J.
Powiązania:
https://bibliotekanauki.pl/articles/2053055.pdf
Data publikacji:
2014
Wydawca:
Akademia Bialska Nauk Stosowanych im. Jana Pawła II w Białej Podlaskiej
Tematy:
organic/farming
structure of land use
taxonomic
method
data clustering
Opis:
The aim of this study is to analyze the structures of land use in organic farming in the EU countries, for which EUROSTAT made the statistics available. The survey concerns the period between 2004 and 2012. The method of data clustering has been used there in order to classify the structure of land use. The taxonomic analysis allowed for differentiating 5 subgroups from the database. They have cross-sectional and time-series character as well as similar cropping patterns. The agricultural sector reacted to the increasing demand for organic products in two ways: by the extension of the crops’ acreage or by the change in the structures of land use (in order to match the product offer with the demand). However, the conducted surveys did not reveal the essential changes in the structures of land use. In consequence, a significant level of stabilization of supply’s structure was noted.
Celem opracowania jest analiza struktury użytkowania gruntów wykorzystywanych przez rolnictwo ekologiczne w krajach należących do UE, dla których EUROSTAT udostępnił odpowiednie dane statystyczne. Badanie objęło lata 2004-2012. Do klasyfikacji struktury użytkowania gruntów zastosowano metodę analizy skupień. Analiza taksonomiczna umożliwiła wydzielenie ze zbioru danych 5 podgrup o charakterze przekrojowo-czasowym, które cechują się podobnymi strukturami upraw. Odpowiedzią sektora rolnego na wzrastający popyt na produkty ekologiczne jest zwiększanie areału upraw bądź zmiana struktury użytkowania ziemi (celem dopasowania oferty produktowej do popytu). Jednak, przeprowadzone badania nie wykazały zasadniczych zmian struktury wykorzystania gruntów w czasie, czego następstwem jest znaczny stopień stabilizacji struktury podaży.
Źródło:
Economic and Regional Studies; 2014, 07, 4; 22-32
2083-3725
2451-182X
Pojawia się w:
Economic and Regional Studies
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Taxonomic structure of Digenea in wild ducks [Anatinae] from West Pomerania
Autorzy:
Kavetska, K M
Rzad, I.
Sitko, J.
Powiązania:
https://bibliotekanauki.pl/articles/840542.pdf
Data publikacji:
2008
Wydawca:
Polskie Towarzystwo Parazytologiczne
Tematy:
bird
parasitic fauna
aquatic environment
Digenea
duck
wild duck
Anatinae
Anseriformes
helminth
taxonomic structure
West Pomeranian region
Polska
Źródło:
Annals of Parasitology; 2008, 54, 2; 131-136
0043-5163
Pojawia się w:
Annals of Parasitology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Taxonomic structure of Digenea in wild ducks [Anatinae] from West Pomerania
Autorzy:
Kavetska, K. M.
Rząd, I.
Sitko, J.
Powiązania:
https://bibliotekanauki.pl/articles/2143748.pdf
Data publikacji:
2008
Wydawca:
Polskie Towarzystwo Parazytologiczne
Tematy:
bird
parasitic fauna
aquatic environment
Digenea
duck
wild duck
Anatinae
Anseriformes
helminth
taxonomic structure
West Pomeranian region
Polska
Opis:
Parasitic fauna of birds connected with water environment, including digeneans, is relatively well researched in Poland. The exception, however, is West Pomerania, where those birds were not frequent objects of parasitological research until recently. The purpose of this work is to determine the taxonomic structure of the Digenea, parasitising wild ducks living in West Pomerania. The research material was 124 individuals of wild Anatinae (Anseriformes) belonging to 8 species: Anas strepera, A. crecca, A. platyrhynchos, Aythya marila, A. fuligula, Melanitta nigra, M. fusca and Mergus merganser. The ducks were obtained in the years 2001–2006 from small ponds near Szczecin, Lake Dąbie, the Szczecin Lagoon and the Baltic Sea. The research showed the presence of 29 species of digeneans from 11 families: Paracoenogonimus ovatus Katsurada, 1914; Diplostomum mergi Dubois, 1932; D. parviventosum Dubois, 1932; D. phoxini (Faust, 1918); D. pusillum (Dubois, 1928); Ornithodiplostomum scardinii (Shulman in Dubinin, 1952); Echinochasmus spinulosus (Rudolphi, 1808); Echinoparyphium cinctum (Rudolphi, 1802); E. recurvatum (Linstow, 1873); Echinostoma miyagawai Ischii, 1932; E. revolutum (Fröhlich, 1802); Hypoderaeum conoideum (Bloch, 1782); Stephanoprora pseudoechinata (Olsson, 1876); Cryptocotyle concava (Creplin, 1825); C. lingua (Creplin, 1825); Leucochloridiomorpha lutea (von Baer, 1826); Catatropis verrucosa (Fröhlich, 1789); Notocotylus attenuatus (Rudolphi, 1809); Paramonostomum alveatum (Mehlis, 1846); Metorchis xanthostomus (Creplin, 1846); Prosthogonimus ovatus (Rudolphi, 1803); P. rarus Braun, 1901; Psilochasmus oxyurus (Creplin, 1825); Psilostomum brevicolle (Creplin, 1829); Psilotrema simillimum (Mühling, 1898); Bilharziella polonica (Kowalewski, 1895); Apatemon gracilis (Rudolphi, 1819); Australapatemon minor (Yamaguti, 1933); Cotylurus cornutus (Rudolphi, 1808).
Źródło:
Wiadomości Parazytologiczne; 2008, 54, 2; 131-136
0043-5163
Pojawia się w:
Wiadomości Parazytologiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zastosowanie taksonomicznej analizy danych lotniczego skanowania laserowego do rozpoznania pionowej struktury drzewostanu i jej przestrzennej zmienności
Taxonomic analysis of airborne laser scanning data for the recognition of stand vertical structure and its spatial variability
Autorzy:
Będkowski, K.
Powiązania:
https://bibliotekanauki.pl/articles/979264.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
pinus sylvestris
forest stand
spatial structure
segmentation
taxonomic analysis
LiDAR
Opis:
The aim of the research was to develop and verify the usefulness of the algorithm for grouping multi−feature objects known as Ward’s taxonomic method for distinguishing homogeneous spatial structures in a forest stands. Scots pine forest stand (20.137720 E, 51.754974 N) was divided into 10 zones differing in the share of undergrowth and up−growth of deciduous species, and the presence of single oak trees growing to the upper layer. The LiDAR data obtained in the first days of May 2007 was used. 459 sample plots of a radius of R=11.28 m located in a 20×20 m grid were set up in the study area. Histograms of spatial distribution of airborne laser scanning pulses were made for them. The histograms are described using eight variables: (1) height above ground level of the highest point of reflection of the laser pulse, (2) height above the upper maximum of the histogram, (3) height above ground level of the lower maximum of the histogram, (4) share of pulses reflected in the upper maximum of the histogram in the total number of pulses, (5) share of pulses in the area of the lower maximum of the histogram in the total number of pulses, (6) share of pulses of the first histogram layer in the total number of pulses, (7) share of pulses in the lower layers of the histogram (from layer no. 2 to no. 11, i.e. from 0.5 to 5.5 m) in the total number of pulses in layers 1−11, i.e. from 0 to 5.5 m, as well as (8) average height above ground of the reflection places of all pulses. The measure of the similarity of the extracted structures was the Euclidean distance of the points representing the histograms in the multidimensional feature space. The results of the division (segmentation) of forest space using the Ward’s method into 2 to 9 groups were analysed. It was found that the obtained divisions are related to the tree stand zones distinguished during the inventory carried out in the field. The proposed taxonomic method of LiDAR data analysis allows for the identification of homogeneous spatial structures in forest stands.
Źródło:
Sylwan; 2020, 164, 10; 805-819
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zooplankton structure in high latitude fjords with contrasting oceanography (Hornsund and Kongsfjorden, Spitsbergen)
Autorzy:
Ormanczyk, M.R.
Gluchowska, M.
Olszewska, A.
Kwasniewski, S.
Powiązania:
https://bibliotekanauki.pl/articles/47860.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
zooplankton
stock size
Hornsund Region
Kongsfjorden
Spitsbergen
taxonomic composition
size structure
biogeography
hydrography
trophic relation
Atlantic water
environment change
Opis:
Zooplankton inhabiting the Hornsund and Kongsfjorden fjords on Spitsbergen (Svalbard) were investigated in summer 2013. The goal of the study was to determine how the zooplankton communities vary in environments functioning under different oceanographic regimes. Sampling was conducted with nets of different mesh size and selectivity (56 μm WP-2, 180 μm MultiNet, and 1000 μm Tucker Trawl), which permitted comparing a wide size spectrum of zooplankton components. Species composition did not differ substantially between the fjords, but the zooplankton in Hornsund was almost two times less numerous, and it had lower biomass per unit volume. The highest abundance at both sites was in the smallest zooplankton size fraction found only in samples taken with 56 μm mesh WP-2 net. These comprised as much as 71% and 58% of the total zooplankton abundance in Hornsund and Kongsfjorden, respectively. The communities in both fjords had comparable contributions of Arctic and boreo-Arctic species biomass in the year of the study. However, the comparison of zooplankton characteristics over several years showed changes in abundance and biogeographic structure that corresponded with variations in the physical environments of the fjords. The results of the study permit predicting the possible effects of the increasing influence of Atlantic waters on zooplankton communities inhabiting Arctic marine pelagic ecosystems.
Źródło:
Oceanologia; 2017, 59, 4
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-7 z 7

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