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Wyświetlanie 1-23 z 23
Tytuł:
Ocena zmian struktury pracujących w unijnych regionach szczebla NUTS 2 z wykorzystaniem miary Braya i Curtisa
Structural changes of employment in EU NUTS 2 regions evaluated with Bray & Curtis measure
Autorzy:
Markowska, Małgorzata
Powiązania:
https://bibliotekanauki.pl/articles/438833.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet Pedagogiczny im. Komisji Edukacji Narodowej w Krakowie
Tematy:
regiony NUTS 2
sektory gospodarki
struktury pracujących
zróżnicowanie struktur
NUTS 2 regions
economic sectors
employment structure
structure diversity
Opis:
Celem artykułu jest ocena zmian struktury pracujących, zaobserwowanych w europejskiej przestrzeni regionalnej szczebla NUTS 2. Struktura pracujących zostanie ujęta w układzie trzech sektorów gospodarki, czyli rolnictwa, przemysłu i usług. Zakres czasowy prowadzonych badań dotyczy dwóch zazębiających się okresów, lat 2000–2008 i 2008–2012, co wynika ze sposobu prezentacji danych w bazach Eurostatu (zmiana podejścia do nomenklatury Europejskiej Klasyfikacji Działalności Gospodarczej NACE z 1997 roku, która w 2008 roku została uaktualniona). Przyczyny zmian to głównie pojawienie się nowych dziedzin działalności, zwłaszcza tych związanych z usługami i technologiami informacyjnymi oraz komunikacyjnymi. W nowym układzie NACE różnią się głównie dane na temat działalności firm, a z tego powodu także dane dotyczące rynku pracy, w tym – przykładowo – zmieniły się definicje pracujących w przemysłach wysokiej technologii i usługach opartych na wiedzy, co spowodowało utratę porównywalności. Jako metodę badawczą zastosowano w pracy miarę zróżnicowania struktur, co umożliwi identyfikację intensywności przeobrażeń na rynku pracy w czasie i przestrzeni.
The aim of the paper is the evaluation of the changes observed in the employment structure at the European regional space of NUTS 2 level. The employment structure is expressed in three elements: agriculture, industry and services. Data covers two overlapping periods: 2000–2008 and 2008–2012. This is because of the changes in Eurostat data bases imposed by the update of European Classification of Economic Activities introduced in 2008 to the original regulation from 1997. New activities were defined, mainly in the field of information services and technologies. In new system, information on enterprises and labour market and some definitions in high-tech industries and services are not fully comparable with the old one. This problem is discussed in the paper. The measure of structures diversity is the basic research method for the analysis presented in the paper. It makes it possible to identify the intensity of labour market changes in both time and space.
Źródło:
Prace Komisji Geografii Przemysłu Polskiego Towarzystwa Geograficznego; 2015, 29, 2; 7-22
2080-1653
Pojawia się w:
Prace Komisji Geografii Przemysłu Polskiego Towarzystwa Geograficznego
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Przestrzenne zróżnicowanie struktury społecznej wsi
Spatial Diversity of Rural Social Structure
Autorzy:
Halamska, Maria
Powiązania:
https://bibliotekanauki.pl/articles/652490.pdf
Data publikacji:
2017
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
struktura społeczna
przestrzeń społeczna
dezagraryzacja
proletaryzacja
burżuazyjnienie
zróżnicowanie struktury społecznej
social structure
social space
desagrarisation
proletarisation
bourgeoisement
diversity of social structure
Opis:
The social structure of the Polish countryside has deeply changed during the last thirty years because of three co-occurring processes: desagrarisation/depeasantisation, proletarisation, and bourgeoisement/gentrification. Representative studies dating from 1991, 2003, and 2013 show changes in fundamental elements of the social position of rural population, namely sources of income, education level, and professional structure. At present, the dominating segment of the social structure of the countryside is workers (45.6%), whereas ratios of farmers and of the so-called new middle class are the same (27.2% each). The spatial diversification of this structure is, however, strong, as exemplified by differences between historical regions (territories formerly belonging to Prussia, Austria, and Russia), multi-functional urbanised vs. mainly rural areas, and administrative units (voivodeships). The most important differences in social structure and the dynamics of its change are between multi-functional urbanised and mainly rural areas.  
W ostatnim trzydziestoleciu struktura społeczna polskiej wsi gruntownie się zmieniła. Sprawiły to trzy, nakładające się, procesy: dezagraryzacja/depezantyzacja, proletaryzacja oraz burżuazyjnienie/gentryfikacja. Autorka, na podstawie danych z reprezentatywnych badań prowadzonych w latach 1991, 2003 oraz 2013, ukazuje zmiany w zakresie podstawowych elementów położenia społecznego ludności wiejskiej: źródeł dochodów, poziomu wykształcenia oraz struktury zawodowej. Dominującym segmentem w strukturze społecznej wsi są obecnie robotnicy (45,6%), natomiast udział rolników i tzw. nowej klasy średniej równoważy się i wynosi po 27,2%. Istnieje jednak duże przestrzenne zróżnicowanie tej struktury, co ukazane zostało na przykładzie regionów historycznych (byłe zabory), obszarów wielofunkcyjnych zurbanizowanych i głównie rolniczych oraz regionów polityczno-administracyjnych (województwa). Największe różnice w strukturze społecznej i dynamice zmian istnieją między obszarami wielofunkcyjnymi zurbanizowanymi a obszarami głównie rolniczymi.
Źródło:
Acta Universitatis Lodziensis. Folia Sociologica; 2017, 63; 7-27
0208-600X
2353-4850
Pojawia się w:
Acta Universitatis Lodziensis. Folia Sociologica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Never forget where you come from: Critical diversity literacy and structure-facing virtue among first-year students
Autorzy:
Conradie, Marthinus
Lasocka-Bełc, Olga
Powiązania:
https://bibliotekanauki.pl/articles/37257797.pdf
Data publikacji:
2024-06-25
Wydawca:
Akademia Pedagogiki Specjalnej. Language and Society Research Committee
Tematy:
critical diversity literacy
structure-facing virtue
racism
Opis:
This article investigates tensions that arose when a group of Learning Facilitators (LFs) and students collaboratively examined the socially constructed nature of racial identity. These discussions transpired in a South Africa Department of English, in an introductory module in postcolonial literature designed for first-year students. The core contribution of the article lies in conjoining critical diversity literacy (CDL) and structure-facing virtue to theorise this tension. It also produces suggestions for deepening the emancipatory potential of such discussions about identity and power in ways that are intended to be relevant to other settings in which comparable discussions are occurring between students and contractually appointed university teachers like LFs.
Źródło:
Language, Discourse & Society; 2024, 12, 1 (23); 73-92
2239-4192
Pojawia się w:
Language, Discourse & Society
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Genetic status of Polish larch (Larix decidua subsp. polonica (Racib. Domin)) from Chełmowa Mountain: implications for gene conservation
Autorzy:
Litkowiec, M.
Lewandowski, A.
Burczyk, J.
Powiązania:
https://bibliotekanauki.pl/articles/2078281.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
European larch
genetic diversity
microsatellites
spatial genetic structure
Opis:
The Polish larch (Larix decidua subsp. polonica (Racib. Domin), a subspecies of European larch, is one of the most valuable forest-forming trees in Poland. It was first discovered on the Chełmowa Mountain where Natural Reserve has been established to protect this subspecies. Currently, this unique population is at risk of extinction. Nonetheless, the knowledge on the genetic diversity of this population and surround- ing larch forests is insufficient to undertake actions aimed at conservation of genetic resources. In this study, we examined the level of genetic diversity and differentiation of four subpopulations of Polish larch from Nature Reserve on the Chełmowa Mountain and surrounding areas. We used eleven nuclear microsatellite markers (SSRs) combined in two multiplex PCR reactions. In total, 344 individuals of Polish larch were genotyped and subjected to further population genetic analyses. We found the high level of genetic diversity (average: He = 0.752, Ho = 0.720) and low levels of genetic differentiation (average: Fst = 0.022). The effective population size was large and homogeneous across subpopulations (mean Ne=90.7), and we found no sign of inbreeding. The spatial genetic structure was detected in two older subpopulations but not in the younger one, suggesting its artificial origin. The old larch subpopulations were genetically homogeneous and they were related to the ancestral group of Polish lowland populations. The old larch core populations growing on Chełmowa Mountain are relatively homogeneous and they well represent the ancestral genetic group of Polish lowland larch populations. However, they still exhibit rela- tively high genetic diversity and sufficiently large effective population sizes assuring their adaptive potential for a long-term existence. Surrounding larch populations are even more genetically diverse but this might be the effect of an admixture of seed sources from various populations from a wider area of Central Europe. We recommend that specific conservation efforts should be undertaken to promote natural regeneration of the core larch populations, even supplemented by the planting of seedlings derived from the oldest larch trees. Other management actions should focus on limiting external gene flow to this unique population of Polish larch.
Źródło:
Dendrobiology; 2018, 80; 101-111
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Microspatial structure of the seed bank of xerothermic grassland - intracommunity differentiation
Autorzy:
Czarnecka, J
Powiązania:
https://bibliotekanauki.pl/articles/56952.pdf
Data publikacji:
2004
Wydawca:
Polskie Towarzystwo Botaniczne
Tematy:
microspatial structure
spatial structure
intracommunity differentiation
species diversity
seed bank
xerothermic grassland
Opis:
The study analyses the quantity and spatial structure of the seed bank of the xerothermic grassland located in the Biała Góra near Tomaszów Lubelski (Central Roztocze Region). The seed stock of the bank was compared with the vegetation found in two different patches of the examined grassland. The number of seeds per square meter was estimated at 5328 and 5355, depending on the patch. The seed bank's spatial organisation is clustered. The most important factors determining this spatial distribution are: remaining of the seeds in close vicinity of parent plants, and the "group" dispersal of the seeds and fruits.
Źródło:
Acta Societatis Botanicorum Poloniae; 2004, 73, 2
0001-6977
2083-9480
Pojawia się w:
Acta Societatis Botanicorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Przestrzenne zróżnicowanie ludności według wieku w Polsce w latach 1991-2010
Differentiation of the Population by Age and Voivodships in Poland, 1991-2010
Autorzy:
Podogrodzka, Małgorzata
Powiązania:
https://bibliotekanauki.pl/articles/587195.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet Ekonomiczny w Katowicach
Tematy:
Ludność
Struktura demograficzna
Zróżnicowanie regionalne
Demographic structure
Population
Regional diversity
Opis:
From two decades we have observed changing of demographic processes (and these processes were not similar by voivodships) which have lead to changed of structure of the population by age. Purpose of the article is a description of it, extract the similar regions and assessment of the regions structures of the population to the progressive pyramid of age. This approach will allow to assessment of the spatial dynamics of the process of ageing of the population.
Źródło:
Studia Ekonomiczne; 2014, 167; 62-76
2083-8611
Pojawia się w:
Studia Ekonomiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
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:
Biodiversity of the crop structure on farms participating in the Polish FADN in terms of the requirements of the Common Agricultural Policy
Autorzy:
Madej, Andrzej
Powiązania:
https://bibliotekanauki.pl/articles/2163437.pdf
Data publikacji:
2023-01-31
Wydawca:
Instytut Uprawy Nawożenia i Gleboznawstwa – Państwowy Instytut Badawczy
Tematy:
crop structure
crop diversity and uniformity
natural environment
Polish FADN
Opis:
The crops structure (or cropping pattern) of a farm is a production and economic feature of a farm. In addition, it is an element shaping the biodiversity of rural areas.The paper presents research on the diversity and uniformity of the structure of crops on farms of various production directions and economic size, participating in the Polish FADN network. We use three biodiversity indicators: the number of plant species cultivated on the farm, the Shannon-Wiener index (H’) and the Pielou equality index (J’).The research showed the differences of the biodiversity indicator of the crop structure and its uniformity. The greatest diversity (Shannon-Wiener index) (H’ = 1.59) and uniformity (J’ = 0.71) of crops were found on farms with permanent crops, where the share of arable lands did not exceed 25%. Farms with field crops with a high share of industrial plants and potatoes had lower values of the indicators (H’ = 1.42 and J’ = 0.63, respectively), Different results were recorded on farms with granivorous animals, with the lowest diversity (H’ = 0.93) and uniformity (J’ = 0.42). Those farms had also the highest share of cereals in crop structure (75.5%).In the analysis of farms in terms of economic size, the highest value of the crop structure diversity index (H’ = 1.51) was found on big farms (100≤thous. €<500), with the highest share of industrial plants and vegetables in field cultivation. The lowest diversity, decreasing with the economic size of farms, was characteristic for very small farms (2≤thous. €<8) with the highest (75.3%) share of cereals.Taking into account the requirements of crop diversification applicable under greening policy, the limit values of the indicators of diversity and uniformity of the crop structure were determined for farms with more than 10 ha of arable land. The comparison of the crop structure indexes obtained in the research with their limit values for farms with different production directions showed that for all compared groups of farms the diversity of the crop structure exceeded the limit value. On the other hand, the uniformity of the sown structure was at the level of the limit value only on farms with field crops, and in other cases it did not exceed the limit value. In the case of all groups of farms, depending on the economic size, the diversity of the crop structure exceeded the limit value, and in the case of its uniformity, this applied to farms with an economic size of more than 50 thousand €.
Źródło:
Polish Journal of Agronomy; 2022, 51; 55-62
2081-2787
Pojawia się w:
Polish Journal of Agronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Land cover and landscape diversity analysis in the West Polesie Biosphere Reserve
Autorzy:
Chmielewski, S.
Chmielewski, T.J.
Tompalski, P.
Powiązania:
https://bibliotekanauki.pl/articles/24906.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:
land cover
cover structure
landscape diversity
analysis
West Polesie Biosphere Reserve
Opis:
The aim of this research was to present the land cover structure and landscape diversity in the West Polesie Biosphere Reserve. The land cover classification was performed using Object Based Image Analysis in Trimble eCognition Developer 8 software. The retrospective land cover changes analysis in 3 lake catchments (Kleszczów, Moszne, Białe Włodawskie Lakes)was performed on the basis of archival aerial photos taken in 1952, 1971, 1984, 1992, 2007 and one satellite scene from 2003 (IKONOS).On the basis of land cover map structure, Shannon diversity index was estimated with the moving window approach enabled in Fragstats software. The conducted research has shown that the land cover structure of the West Polesie Biosphere Reserve is diverse and can be simply described by selected landscape metrics. The highest level of land cover diversity, as showed by Shannon Diversity Index, was identified in the western part of the West Polesie Biosphere Reserve, which is closely related to the agricultural character of land cover structure in those regions. The examples of three regional retrospective land cover analyses demonstrated that the character of land cover structure has changed dramatically over the last 40 years.
Źródło:
International Agrophysics; 2014, 28, 2
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of environmental factors and management on dynamics of mixed calcareous forests under climate change in Central European lowlands
Autorzy:
Vancura, K.
Simkova, M.
Vacek, Z.
Vacek, S.
Gallo, J.
Simunek, V.
Podrazsky, V.
Stefancik, I.
Hajek, V.
Prokupkova, A.
Kralicek, I.
Powiązania:
https://bibliotekanauki.pl/articles/2130171.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
hornbeam-oak groves
beech forests
stand structure
diversity
radial growth
Czech Republic
Opis:
Mixed lowland forests reserved for natural succession are sparse in the Czech Republic. However, their development provides essential insights into the natural processes of these forests and recommendations for forest management in a changing climate. The research describes the dynamics, productivity, structure, diversity, dead wood, and radial growth of hornbeam-oak groves and calcareous beech-dominated forests in the Karlštejn National Nature Reserve (Czechia) based on inventory in 2002, 2008, 2014 and 2020. The objective was to evaluate changes in differently managed stands (high forest, coppice with standards, and coppice) after leaving the stands to spontaneous development in 2004. The tree density increased by 2–10% from 2002 to 2014 and decreased by 6–18% in 2020. In the high forest, an increase in the stand volume was observed during the whole period, while in the coppice with standards and coppice, only until 2014. The stand volume ranged from 190 (coppice) to 630 (high forest) m³ ha−1 in 2020 and increased by an average of 28% over 18 years. Overall diversity of tree layer showed an uneven structure in the high forest and a substantially diverse structure in the other variants. The deadwood volume has been steadily increasing (18–35 m³ ha−1 in 2020), accumulating an average of 1 m³ ha−1 yr−1. A lack of precipitation and high temperatures from June to August were the main limiting factors of the radial growth of tree species, while the number of negative pointer years has increased in the last decade. European beech (Fagus sylvatica L.) was the most sensitive tree species to climate compared to the resilient European ash (Fraxinus excelsior L.). The lowest fluctuations in the diameter increment were recorded in Norway maple (Acer platanoides L.) and the highest in beech in the temperature cycles of 7–15 years. Over the last 20 years, sessile oak [Quercus petraea (Matt.) Liebl.] showed an increase in radial growth by 7%, while other tree species reported a decrease with a maximum in beech (by −38%). The forest stands managed as high forest, characterized by a higher production potential and lower diversity, had slower dynamics when compared to coppice with standards and coppice.
Źródło:
Dendrobiology; 2022, 87; 79-100
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of genetic diversity of Ficus carica L. (Moraceae) collection using simple sequence repeat (SSR) markers
Autorzy:
Marcotuli, I.
Mazzeo, A.
Nigro, D.
Giove, L.
Giancaspro, A.
Colasuonno, P.
Prgomet, Ž.
Prgomet, I.
Tarantino, A.
Ferrara, G.
Gadaleta, A.
Powiązania:
https://bibliotekanauki.pl/articles/12664546.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Przyrodniczy w Lublinie. Wydawnictwo Uniwersytetu Przyrodniczego w Lublinie
Tematy:
Moraceae
common fig
Ficus carica
population structure
genetic analysis
genetic diversity
SSR marker
Opis:
Modern technologies and accurate information on genetic diversity and structure are contributing to improve the plant breeding, in particular for all the minor species with a lack of data. Genetic diversity of 139 different Ficus carica L. genotypes collected from Italy and Croatia, and divided into two subgroups: uniferous (only main crop) and biferous (breba and main crop), was investigated using 49 microsatellite markers. A total of 70 alleles were generated, of which 64 (91.4%) showed a polymorphic pattern indicating high level of genetic diversity within the studied collection. The mean heterozygosity over the 64 single locus microsatellites was 0.33 and the expected and observed averaged variance were 16.50 and 184.08, respectively. The 139 fig genotypes formed two clusters in the PCoA analysis, suggesting a division between Italian and Croatian genotypes. Moreover, the fig accessions could be divided into two main clusters based on the STRUCTURE analysis according to the biological type, uniferous or biferous, with partly overlapping varieties. In conclusion, our results demonstrated that molecular markers were able to discriminate among genotypes and useful for the authentication of fig tree varieties (homonymies and synonymies).
Źródło:
Acta Scientiarum Polonorum. Hortorum Cultus; 2019, 18, 4; 93-109
1644-0692
Pojawia się w:
Acta Scientiarum Polonorum. Hortorum Cultus
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Genetic diversity of North African Thymus algeriensis in Tunisia: Population structure and implication for conservation
Autorzy:
Ben El Hadj Ali, I.
Guetat, A.
Boussaid, M.
Powiązania:
https://bibliotekanauki.pl/articles/41188.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
genetic diversity
North Africa
Thymus algeriensis
Tunisia
population structure
molecular marker
natural population
conservation
Opis:
The genetic diversity within and among nine natural populations of Thymus hirtus Willd. subsp. algeriensis (Boiss. et Reut.) Murb. from different geographical and bioclimatic zones were assessed using Random Amplified Polymorphic DNA data. A total of 154 bands were generated from seven selected primers. 141 bands were polymorphic (P=91.56%). The genetic diversity within a population based on Shannon's index which was high (H'pop=0.307) and varied according to bioclimatic zones. A high genetic differentiation among populations (GST=0.335 and FST=0.296) was revealed, suggesting a population isolation and a low level of gene flow among them. The major proportion of the variation was attributable to individual differences within populations. The genetic structure is in accordance with geography distances. The Neighbour- joining tree based on Nei's and Li's genetic distance among individuals showed that individuals from each population clustered together. The UPGMA dendrogram based on FST values revealed three clusters each of them includes populations closuring to their geographical origin. The high genetic structure of populations resulted from genetic drift caused both by the habitat fragmentation and the low size of most populations. The in situ conservation should interest all populations. The ex situ conservation should be based on the collection of seeds rather within than among populations because of the maximum of variation was revealed within populations.
Źródło:
Dendrobiology; 2012, 67
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Genetic diversity of wild Thymus capitatus (Lamiaceae) in Tunisia using molecular markers
Autorzy:
Ben El Hadj Ali, I.
Guetat, A.
Boussaid, M.
Powiązania:
https://bibliotekanauki.pl/articles/41663.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
genetic diversity
wild plant
Thymus capitatus
Lamiaceae
Tunisia
molecular marker
habitat fragmentation
conservation strategy
genetic structure
Opis:
In Tunisia, Thymus capitatus L. populations are severely destroyed due to deforestation and over-collecting. The species occurs in small scattered populations decreasing progressively in size. Yet, no conservation or improvement programs are attempted to preserve and promote the potential value of this resource. In this work, we assessed the genetic diversity of nine Tunisian populations of Thymus capitatus L. from different bioclimates, using 103 polymorphic randomly amplified polymorphic DNA (RAPD) loci. The analysis of the genetic variation within and among populations is primordial to elaborate conservation and improvement programs. The species showed a low diversity within populations (0.276
Źródło:
Dendrobiology; 2012, 68
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Low genetic diversity in the endangered population of Viola uliginosa in its locus classicus at Rzaska near Cracow [southern Poland] as revealed by AFLP markers
Autorzy:
Cieslak, E
Paul, W.
Ronikier, M.
Powiązania:
https://bibliotekanauki.pl/articles/58111.pdf
Data publikacji:
2006
Wydawca:
Polskie Towarzystwo Botaniczne
Tematy:
genetic diversity
endangered population
Viola uliginosa
Rzaska n.Krakow
Polska
AFLP marker
plant conservation
rare plant
threatened plant
wet habitat
genetic structure
population structure
Opis:
An extremely endangered population of Viola uliginosa Besser at the classical locality of this taxon has been studied. The AFLP analysis was based on 18 specimens of V. uliginosa (about 10% of preserved individuals); additionally, two individuals of V. riviniana were included in the data set as the out group. A high genetical uniformity of the whole population (similarity indexes close to 1) was detected. It was not correlated significantly with the spatial distribution of the plants. The study serves as a basis for practical conservation measures and at the same time as a starting point for a more extensive research on the genetical variability of the species throughout its range.
Źródło:
Acta Societatis Botanicorum Poloniae; 2006, 75, 3; 245-251
0001-6977
2083-9480
Pojawia się w:
Acta Societatis Botanicorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Implication of forest zonation on tree species composition, diversity and structure in Mabira Forest, Uganda
Autorzy:
Weldemariam, E.C.
Jakisa, E.S.
Ahebwe, D.A.
Powiązania:
https://bibliotekanauki.pl/articles/9997.pdf
Data publikacji:
2017
Wydawca:
Fundacja na Rzecz Młodych Naukowców
Tematy:
forest zonation
management zone
tree
woody species
plant species
species composition
species diversity
species structure
Mabira Forest Reserve
Uganda
Opis:
The study aimed to investigate effectiveness of forest management zoning in conserving biodiversity of Mabira forest reserve. The study sites buffer, production, and strict nature reserve management zones were purposively selected. This was undertaken through investigating woody species diversity, composition and structure. A total of 60 sampling plots with a size of 20 m x10 m were used to collect vegetation data. Variables such as woody plant species identification and counts as well as diameter at breast height (DBH) of trees were done. The result depicted a total of 65 woody species; 39 in buffer, 19 in productions and 37 in strict nature reserve. Of these, only 9 trees species were found common to all zones and their Sorensen similarity coefficient was 0.2213. The population structure of the buffer and strict nature reserve zones was found to be a J - shape pattern, whereas the production zone shown an inverted J-shape pattern. Higher woody species diversity was depicted in the buffer and strict nature zones with (H’=2. 73512) and (H’=2. 68412) respectively, and lower in a production zone (H’=1. 63628). The evenness index value of a buffer zone was (J =0. 746574), strict nature (J= 0.743335) and production (J=0. 555719). The production zone had shown higher IVI values followed by buffer and strict nature reserve zone. The most important woody species identified based on their IVI value were Broussonetia papyrifera (Production), Acalypha neptunica (Buffer), Funtumia Elastica (strict nature reserve). The existing forest management is effective in conserving the biodiversity of the forest reserve. Nevertheless, the production zone was still suffering from exploitation of the surrounding community, hence serve for protecting the remaining management zones from further human interference. Further investigation is also required on the adjacent community perceptions of the forest management zoning.
Źródło:
Environment, Earth and Ecology; 2017, 1, 1
2543-9774
2451-4225
Pojawia się w:
Environment, Earth and Ecology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Genetic analysis of silver-fir populations in the Beskids
Autorzy:
Mejnartowicz, L
Powiązania:
https://bibliotekanauki.pl/articles/58866.pdf
Data publikacji:
2003
Wydawca:
Polskie Towarzystwo Botaniczne
Tematy:
silver fir population
Abies alba
genetic distance
isoenzyme
Beskids Mountains
genetic structure
heterozygosity
genetic analysis
genetic diversity
population
genetic variation
Opis:
Twenty-eight isozymic loci were studied in the Beskid Mts., in four populations of common silver-fir (Abies alba): one in Beskid Makowski (BM) and three populations in Beskid Sądecki (BS). Their genetic variation and diversity were analyzed, and Nei's genetic distances between the populations were calculated. The results show that the geographical distance between the BM population and the three BS populations is reflected in genetic distances. The BM population is clearly distinct from the others. It has the lowest genetic diversity (I = 0.42), percentage of polymorphic loci (%PoL = 64.29) and number of rare alleles (NoRa = 5). Besides, the BM population has the highest observed heterozygosity (Ho = 0.291), which exceeds the expected heterozygosity (He = 0.254), estimated on the basis of the Hardy-Weinberg Principle. On the contrary, BS populations are in the state of equilibrium, which is manifested, in similar values of He = 0.262 and Ho = 0.264.
Źródło:
Acta Societatis Botanicorum Poloniae; 2003, 72, 2
0001-6977
2083-9480
Pojawia się w:
Acta Societatis Botanicorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spring development of hydrolittoral rock shore communities on wave-exposed and sheltered sites in the Northern Baltic proper
Autorzy:
Eriksson Wiklund, A.-K.
Malm, T.
Honkakangas, J.
Eklund, B.
Powiązania:
https://bibliotekanauki.pl/articles/48999.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
spring development
Baltic Sea
community structure
diversity
development
filamentous alga
macroinvertebrate
macroalga
biomass
intertidal zonation
rocky shore
dynamic environment
alga
Opis:
Spring development in the hydrolittoral zone was investigated at five wave-sheltered and five wave-exposed sites on four occasions from late March to late May (every third week). The number of species was higher at the sheltered locations and increased significantly over time. The difference in community structure was significant: over 95% of the Bray-Curtis dissimilarities were due to the biomass of only eleven taxa, and the total Bray-Curtis dissimilarity between exposed and sheltered sites was 75%. Macroalgae made up 70–80% of the total biomass and was dominated by filamentous species. In contrast to previous studies, macroalgal biomass was higher at the exposed sites, which may be due to the fact that this was a spring study, unlike previous studies, which were conducted during summer.
Źródło:
Oceanologia; 2012, 54, 1
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Structural diversity and production of alder stands on former agricultural land at high altitudes
Autorzy:
Vacek, Z.
Vacek, S.
Podrazsky, V.
Kral, J.
Bulusek, D.
Putalova, T.
Balas, M.
Kalouskova, I.
Schwarz, O.
Powiązania:
https://bibliotekanauki.pl/articles/41581.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
structural diversity
stand structure
alder stand
agricultural land
black alder
Alnus glutinosa
grey alder
Alnus incana
afforestation
succession
Sudetes Mountains
Opis:
The paper deals with the structural diversity and production of a less frequently studied type of alder stands originated on former agricultural lands in the 1950s, established partly by plantation and partly by natural succession in the area of the Krkonoše Mts. and the Orlické hory Mts. (Czech Republic). Four permanent research plots (PRP) were established at sites where Black alder (Alnus glutinosa L. Gaertn.) and Grey alder (Alnus incana L. Moench.) naturally occurs, each plot of 0.25 ha in size. The aim of the study was to evaluate the structure and development of the alder stands with respect to biodiversity, horizontal, vertical and species structure, diameter increment with emphasis on climate factors, and the quantity and quality of timber production. The results document low diversification of the studied stands in the PRPs. The horizontal structure is defined as random and clumped at sites at the highest altitude with high water table. The number of living trees with DBH ≥ 4 cm ranges between 556 to 828 trees ha-1 with the relative stand density index (SDI) 0.67–0.77. The stand volume ranges from 247 to 393 m3 ha–1, and decreases with higher altitudes. Low temperatures is limiting factor for radial growth in the high mountain areas, respectively low precipitation in the middle lands. Owing to a rather specific site character, as especially the spring area, the stands exhibit only average production, but the production quality is generally high. The quality timber is suitable for industrial use; the rot-affected trunk base parts usable for fuel represent only approximately 16%.
Źródło:
Dendrobiology; 2016, 75
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Genotypic Population Structure of Ascochyta Pinodes and Phoma Pinodella in Poland
Autorzy:
Furgał-Węgrzycka, Helena
Węgrzycki, Michał
Powiązania:
https://bibliotekanauki.pl/articles/2199175.pdf
Data publikacji:
2009-06-21
Wydawca:
Instytut Hodowli i Aklimatyzacji Roślin
Tematy:
Mycosphaerella (Didymella) pinodes anamorph Ascochyta pinodes
Phoma pinodella (teleomorph Didymella)
genotypic population structure
components the genetic variation of population
VCG frequency
spatial and temporal VCG diversity
Opis:
The genotypic populations structure of Ascochyta pinodes and Phoma pinodella was de ter mined across a hierarchy of spatial and temporal scale by using vegetative in compatibility system as phenotypic genetic marker. Components of genetic variation within and be tween populations included the following values: in dices of diversity H’, richness (g), indices of evenness E1, E2 and E5, spatio-temporal analysis of genotypic variation (HT and HS val ues), pairwise comparisons of geno type diversity, distribution of VCGs across spatio-temporal scale (GST value) and analysis of variance calculated on VCGs ge no type frequencies within populations... 
Źródło:
Plant Breeding and Seed Science; 2009, 59; 21-52
1429-3862
2083-599X
Pojawia się w:
Plant Breeding and Seed Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Phytoplankton and environmental variables as a water quality indicator for the beaches at Matrouh, South-Eastern Mediterranean Sea, Egypt: an assessment
Autorzy:
Gharib, S.M.
El-Sherif, Z.M.
Abdel-Halim, A.M.
Radwan, A.A.
Powiązania:
https://bibliotekanauki.pl/articles/48802.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
abiotic environment
beach
biotic environment
community structure
diversity index
Egypt
environment variability
hydrochemical change
hydrographic change
marine environment
Matrouh beach
Mediterranean Sea
nutrient concentration
phytoplankton
water quality
Opis:
This study was carried out to determine the water quality of the beaches at Matrouh, south-eastern Mediterranean Sea, Egypt, by studying environmental variables as well as phytoplankton abundance and community structure. Surface water samples were monitored from a series of beach sites over a period of five seasons during 2009–2010. A total of 203 phytoplankton species were identified from seven algal divisions. Seasonal differences in the quantitative and qualitative composition of the phytoplankton communities in the different sites were marked. Nutrient concentrations and phytoplankton abundances were found to be poorer than those of many other areas along Egyptian coast. The Shannon-Wiener Diversity Index classified Matrouh water as being between clean and moderately polluted, whereas the WQI demonstrated that it was between good and excellent. It can be concluded that the index based onWQI is currently more suitable than the phytoplankton species index for assessing the quality of the water of the Matrouh beaches.
Źródło:
Oceanologia; 2011, 53, 3
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
ISSR analysis points to relict character of Aconitum bucovinense Zapal. (Ranunculaceae) at the range margin
Autorzy:
Boron, P.
Zalewska-Galosz, J.
Sutkowska, A.
Zemanek, B.
Mitka, J.
Powiązania:
https://bibliotekanauki.pl/articles/59093.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Botaniczne
Tematy:
Carpathians Mountains
conservation genetics
endemic species
marginal population
schizo-endemism
relict population
Aconitum bucovinense
Ranunculaceae
Polish Red Data Book of Plants
genetic diversity
genetic structure
ISSR technique
Opis:
Aconitum bucovinense, a high-mountain species endemic to the Eastern and Southern Carpathians, including the Apuseni Mountains, is legally protected and classified in the Polish Red Data Book of Plants. It attains its NW geographical range in two peripheral populations in the Western Bieszczady Mountains (Polish Eastern Carpathians), isolated by a distance of 13.1 km. PCR-ISSR analysis has been used to elucidate the within- and among-populational levels of species genetic diversity. A UPGMA and block clustering showed discreteness of the populations and subpopulations based on ISSR banding pattern. Analysis of Molecular Variance (AMOVA) revealed significant divergence (P = 0.024) of the two marginal populations and highly significant (P < 0.001) differentiation of subpopulations within populations. The theta index calculated for the two marginal populations and the core population in the Carpathians was 0.131 ±0.030 S.D. Most of the population-genetic diversity indices of the marginal populations were not different from those in the core area but the Shannon’s and rarity indices were lower in the marginal populations. It seems that founder effect and subsequent genetic bottleneck resulted in a fine-scale population genetic structure. The marginal populations under study need a relevant recovery program to maintain their genetic diversity.
Źródło:
Acta Societatis Botanicorum Poloniae; 2011, 80, 4
0001-6977
2083-9480
Pojawia się w:
Acta Societatis Botanicorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A New Diminutive Wide-band MIMO Antenna with Frequency Agile Features for 4G and 5G Diverse Wireless Applications
Autorzy:
Mudda, Shivleela
K M, Gayathri
Mallikarjun, M
Powiązania:
https://bibliotekanauki.pl/articles/27311969.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
Diversity gain (DG)
Defective ground structure (DGS)
Fractional bandwidth (FBW)
ITU (International Telecommunication Union)
INSAT
Frequency Reconfigurable antenna (FRA)
Multiple input multiple output (MIMO)
mutual coupling
isolation
5G
Envelope correlation coefficient (ECC)
Opis:
This paper demonstrates a low-profile, wide-band, two-element, frequency-reconfigurable MIMO antenna that is suitable for diverse wireless applications of 4G and 5G such as WLAN/Bluetooth (2.4–2.5 GHz), WLAN (2.4–2.484 GHz, 5.15– 5.35 GHz, and 5.725–5.825 GHz), WiMAX (3.3–3.69 GHz and 5.25–5.85 GHz), Sub6GHz band proposed for 5G (3.4–3.6 GHz, 3.6-3.8GHz and 4.4–4.99 GHz), INSAT and satellite X-band(6 to 9.6 GHz). Proposed MIMO favour effortless switching between multiple bands ranging from 2.2 to 9.4 GHz without causing any interference. Both antenna elements in a MIMO array are made up of a single module comprised of a slot-loaded patch and a defective structured ground. Two PIN diodes are placed in the preset position of the ground defect to achieve frequencyreconfigurable qualities. The suggested MIMO antenna has a size of 62 ×25 ×1.5 mm3. Previous reconfigurable MIMO designs improved isolation using a meander line resonator, faulty ground structures, or self-isolation approaches. To attain the isolation requirements of modern devices, stub approach is introduced in proposed design. Without use of stub, simulated isolation is 15dB. The addition of a stub improved isolation even more. At six resonances, measured isolation is greater than 18 dB, the computed correlation coefficient is below 0.0065, and diversity gain is over 9.8 dB.
Źródło:
International Journal of Electronics and Telecommunications; 2023, 69, 3; 439--448
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wpływ trzebieży przerębowej na zróżnicowanie strukturalne drzewostanu
Autorzy:
Bilski, M.
Brzeziecki, B.
Powiązania:
https://bibliotekanauki.pl/articles/1022233.pdf
Data publikacji:
2005
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
dominacja wymiarowa
rozklad piersnic
trzebiez przerebowa
lesnictwo
struktura drzewostanu
rozmieszczenie przestrzenne
drzewa lesne
drzewostany jodlowe
abies alba mill.
angle measure index
bwinpro model
differentiation thinning
diameter distribution
diameter spatial diversity
liocourt−meyer curve
spatial pattern
stand structure
Opis:
The impact of differentiation thinning on various aspects of structure of exemplary Silver fir stand, including overall diameter distribution, diameter spatial diversity, dimension dominance and spatial distribution pattern, is analysed. Comparison of empirical diameter distribution (before and after thinning) with a the−oretical Liocourt−Meyer curve and the results of structural analysis, lead to the general conclusion that in case of relatively simple−structured Silver fir stands, achieving a desired, plenter−like structure is a longterm process, requiring a lot of consistency and patience.
Źródło:
Sylwan; 2005, 149, 04; 21-33
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
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