Wyniki wyszukiwania - Biblioteka Nauki

1

Population structure in the Penna model

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Sitarz M.

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tom Vol. 7, No 2

263-269

EN

Numerical simulations of growing population, based on the Penna model, are presented. We consider biological ageing as a result of the accumulation of mutations in the genotype. We present an example of simulated population structure and compare it with that of a real population. We also discuss the role of bad mutations threshold parameter T in the Penna model, to reproduce a smooth transition from the oversimplified logistic model (T --> ?) to the Penna model.

2

Demographic potential of the countries that have applied for the European Union membership

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Sojka E.

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tom 17

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nr 17

135-145

EN

The purpose of the article is to analyse the demographic potential of the countries that have applied for the European Union membership against the background of the EU member states. The study involves eight candidate states: Croatia, Iceland, Macedonia, Montenegro, and Turkey, i.e. the countries that have been approved by the European Commission as official candidates for the EU membership, as well as Albania, Bosnia and Herzegovina, Serbia, i.e. the potential candidates. Albania and Serbia applied officially for the EU membership in 2009. Favourable population age structure and relatively high fertility rate that occur in these countries determine a significant demographic potential they can bring to the EU after their accession. Decrease in infant mortality rate and extension of life expectancy illustrate positive changes that have been taking place in these countries for the last several years.

3

Struktura populacji cisa pospolitego Taxus baccata L. w Wysokiej Lelowskiej

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Majchrzak B. , Tomala R.

Chemistry, Environment, Biotechnology

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2015

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tom Vol. 18

19--30

PL

Badania populacji cisa przeprowadzono w latach 2010‒2011 w Wysokiej Lelowskiej niedaleko wsi Żarki Letnisko i Przybynów. Wyznaczono 4 poletka badawcze o wymiarach 10 × 20 m. Dla każdego poletka oznaczono wszystkie gatunki roślin, sporządzono listę florystyczną oraz wykonano zdjęcie fitosocjologiczne w aspekcie wiosennym i letnim. Na tej podstawie określono zbiorowisko roślinne jako zdegradowaną postać Fraxino-Alnetum. Populacja cisa składa się z 71 osobników, u których wykonano pomiar wysokości i pierśnicy. Pierśnica cisów zawiera się w przedziale 1‒29 cm. Średnia grubość wynosi 7.27 cm, a średnia wysokość wszystkich osobników to 6.98 m. Najwyższy cis mierzy 13.3 m. Większość cisów jest rozgałęziona (59%) i posiada najczęściej 5, 3 lub 2 pnie. 38% populacji jest jednopniowa. 2 osobniki (3%) mają formę krzewiastą. Średnie zagęszczenie cisów na wszystkich powierzchniach badawczych wynosi 8.8/100 m2. Struktura płciowa została określona dla 97% populacji: 62% to osobniki żeńskie, a 33% męskie. Pomimo przewagi liczby osobników żeńskich w Wysokiej Lelowskiej, populacja nie odnawia się. Odnaleziono tylko 6 siewek o wysokości do 10 cm. Powodem braku odnawiania się cisów może być nadmiernie rozwinięte runo. Z uwagi na dużą liczbę osobników cisa oraz ich dobrą kondycję, badana populacja powinna zostać objęta ochroną rezerwatową.

EN

The research of yew population was carried out in the years 2010‒2011 in Wysoka Lelowska near villages Żarki Letnisko and Przybynów. 4 research plots were established, 10 × 20 meters in dimension. For each research plot, all species was marked and the floristic list was made. The phytosociologial analysis was made in terms of spring and summer. On this basis was stated that the plant community is a degenerated form of Fraxino-Alnetum. The yew population consist of 71 specimens were measured in terms of height and breast height. Breast height of yews ranged between 1 and 29 cm. The average diameter is 7.27 cm and the average height of all specimens is 6.98 m. The tallest yew has reached 13.3 m in height. Most of the yews are branched (59%) and had 5, 3, 2 trunks. 38% population have a monopodium. Two specimens (3%) had a shrubby form. The average density of yews on all plots is 8.8/100 m2. Sex identity was determined in 97% of yews population: 62% were male and 33% female specimens. Despite, that the presence of the female specimens population in Wysoka Lelowska is not regeneration. The seedlings were found in the amount 6 of up to 10 cm. Maybe for reason the yews are not regeneration is over-developed undergrowth. Due to the large number of yews and good condition this population should be protected in nature reserve.

4

Evaluation of genetic diversity and population structure of five yellow catfish Pelteobagrus fulvidraco populations by microsatellite markers

100%

Zhong L. , Wang M. , Pan J. , Li D. , Tang S. , Bian W. , Chen X.

Oceanological and Hydrobiological Studies

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2018

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tom Vol. 47, No. 2

99--106

EN

Yellow catfish, Pelteobagrus fulvidraco, is an important commercial freshwater species in China. Knowledge about the genetic diversity of the yellow catfish is important to support the management and conservation programs, which would subsequently support the sustainable production of this species. To investigate the genetic diversity and the structure of yellow catfish in the middle and lower reaches of the Yangtze River, 125 individuals from five lakes were genotyped using 13 microsatellite markers. Moderate genetic diversity was determined in all populations, with the observed heterozygosity (HO) ranging from 0.42 to 0.49 and the expected heterozygosity (HE) ranging from 0.51 to 0.61. Low to moderate genetic differentiation among the populations was revealed from pairwise FST values (p < 0.05), as well as from analysis of molecular variance (AMOVA). The UPGMA dendrogram and Bayesian clustering analysis indicated a correlation between genetic differences and geographic distance – four populations from the lower reaches clustered together, whereas the Poyang Lake (PY) population formed a separate cluster. The present study would be helpful in the wild stock management and artificial propagation programs for yellow catfish in the middle and lower reaches of the Yangtze River.

5

The influence of disturbances in forest communities upon the spatial organization of Cyclamen hederifolium populations on the Promontorio del Gargano [ Italy ]

100%

Falinska K.

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tom 02

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nr 2

6

Population structure and regeneration of Phragmites australis (Cav.) Trin. ex Steud. in flood control ditches in the depression wetland (Żuławy Wiślane, Northern Poland)

88%

Boszke P. , Bociąg K. , Szmeja J.

Polish Journal of Ecology

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2005

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tom Vol. 53, nr 1

3-12

EN

The population structure of Phragmites australis (Cav.) Trin. ex Steud. was examined in seven categories of overgrowing flood control ditches, differing on time which had elapsed from the last clean-up. Density, biomass, frequency of development stages, as well as the size and habit of the shoots, were determined in the populations. Site conditions in the ditches and the proportion of the common reed in the total biomass of plants were also examined. The rate at which populations in cleaned ditches regenerate is very quick. Three years after the maintenance works in ditches the reed population is already fully regenerated. Well developed reed rushes, which biomass is about 650 g d.w.m-2, are dominant. Its density amounts to 76 ± 25 shoots m-2. Flowering and fruiting shoots are the most numerous. The first signs of population regression were observed in the ditches left without cleaning for more than 5 years. Population density is gradually lower, the proportion of generative shoots is reduced, and the reed is lighter and has smaller assimilation area. In the 11-year-old and older ditches the reed is replaced by other plant species, mainly grasses and shrubs.

7

Changes of population structure of Taxus baccata L. during 25 years in protected area (Carpathians, Western Ukraine)

88%

Iszkuło G. , Boratyński A. , Didukh Y. , Romashenko K. , Pryazhko N.

Polish Journal of Ecology

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2005

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tom Vol. 53, nr 1

13-23

EN

The aim of the study was to assess the present state of the Taxus baccata L. population in the Knyazhdvir Nature Reserve (West Ukraine) and to analyse the population structure changes that had occured during 25 years. We found the tendency towards population ageing but with relatively numerous young individuals and seedlings. Surprisingly, specimens with bi- or trifurcate trunks (polycormic) were significantly thicker than those with single trunks (monocormic). This attest to some kind of dominance of polycormic specimens over monocormic ones.

8

Human Resources of Lithuania: On the Question of the Fate of the Nation

88%

Vaitekūnas S.

Bulletin of Geography. Socio-economic Series

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2008

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tom 10

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nr 10

93-118

EN

The mutual dependence of human resources and the development of the state has been one of the most important geopolitical questions discussed from the times of Ancient Greece. The article analyses the growth of the population and human resources of Lithuania, their change and influence on the state's development, the possible consequences of the decline of the population on international policies and the state's geopolitical situation. Reflecting the changes in the number of inhabitants and their structure five possible scenarios of the state's development in the future are constructed: 1) a small, but economically strong national state; 2) more pensioners than grandchildren; 3) a multinational and multicultural state; 4) the end of the national state (?); 5) a strong economic and cultural state.

9

Population structure of a clonal endangered plant species Iris sibirica L. in different habitat conditions

88%

Kostrakiewicz K.

Polish Journal of Ecology

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2008

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tom 56

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nr 4

581-592

EN

The investigations of structure of the genets and populations of Iris sibirica L. were carried out in the period 1999–2002. The studies were conducted in Molinietum caeruleae patches localized in Southern Poland. The patch labelled MW (“more wet”) measured 5,600 m² and was chracterised by presence of large depressions filled with stagnant water, concentrated chiefly in the central part of the site. In this locality species with a high competitive potential (like Phagmites australis Trin., Chamanerion angustifolium (L.) Scop., Epilobium hirsutum L., Filipendula ulmaria (L.) Maxim. and others) prevailed. The patch called LW (“less wet”) measured 1,800 m² and was characterised by small number of depressions scattered throughout the site. In this locality dominated the plants of minor competitive abilities (like Lathyrus pratensis L., Lotus corniculatus L. and others). The spatial pattern of populations was described on the basis of the locations of all ramet clusters in 100 m² square plots. Each ramet cluster was attributed to a developmental stage. The differences in height of ramets between stages was estimated on the basis of lenght of the tallest leaf and generative shoot measured in all genets and ramet clusters in both populations (30 leaves and all generative shoots in 5 clusters of ramet at generative and senile stages and 4 – at fragmentation phase in both populations). In study year 2000 Iris sibirica population in LW locality was consisted of 26 ramet clusters and showed an aggregation structure, while population growing in MW site was consisted of 502 ramet clusters and presented the group-aggregation spatial structure constituted by groups of dozen or so ramet clusters, forming large aggregations. Both populations showed signs of senility in effect of absence of genets in prereproductive stages. In 2001 and 2002 the seedlings and juvenile genets appeared only in artificially made gaps. The genets in initial stage are much lower (about 40 %) than older ones and the ramet in MW locality reached greather height (6 to 23%) than in LW site. The evaluation of structure of populations taken as indicator of their vitality, show that the population from less wet locality was in better condition despite of low abundance. Domination of ramet cluster at generative stage and vicinity of plants with low competitive potential enables longer existence of Iris sibirica in occupied site. In more wet locality the I. sibirica population is worse equiped to survive. Advanced senility and the vicinity of plants with high competitive potential might inhibit the proliferation of I. sibirica ramet clusters, accelerate their fragmentation or even eliminate from occupied site.

10

A novel polymorphic mtDNA marker for population studies of the pink shrimp, Farfantepenaeus duorarum (Crustacea, Penaeidae)

88%

Grabowski M. , Grater W. D. , Stuck K. C.

Oceanologia

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2004

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tom No. 46 (1)

147-151

EN

The pink shrimp, Farfantepenaeus duorarum, is one of the most important shrimp species commercially harvested along the Gulf and Atlantic coasts of the US. In this study we developed a mitochondrial marker suitable for population studies of the species. A 611-617 bp hypervariable portion of the AT-rich region of the mt genome was amplified and sequenced. The 617 bp long consensus sequence contained 15 polymorphic insertion/deletion sites and 165 polymorphic substitution sites. Kimura 2-parameter distances ranged from 0.00 to 0.06 with a mean of 0.02. Among the 104 sequences, 100 haplotypes were counted if all mutations were included. If transitions were omitted, 34 haplotypes were observed. The results indicate that the hypervariable portion of the AT-rich region may be an effective marker for revealing the genetic structure of the pink shrimp off the southeast US.

11

Vertical migration of Siphonophora (Cnidaria) and their productivity in the Croker Passage, the Antarctic

88%

Panasiuk-Chodnicka A. A. , Żmijewska M. I. , Mańko M.

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nr 1

12

Population parameters and reproductive biology of the Iberian hare Lepus granatensis in Southern Iberia

88%

Farfan M. A. , Vargas J. M. , Real R. , Palomo L. J. , Duarte J.

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nr 3

EN

To analyse the population structure and reproductive biology of the Iberian hare Lepus granatensis Rosenhauer, 1856, 498 hares (264 males and 234 females) were collected in monthly samples from October 1998 to September 1999. Females reached larger sizes than males, with approximately 400 g difference in body mass on reaching sexual maturity. The total sex ratio was 1:1, with a bias in favour of males in winter. Sexually active males and females appeared in every month but August, when no sexually active female was found. Births occurred in every month and were more frequent between March and July. Seasonal variation in kidney fat index (KFI) followed a similar pattern in males and females, with an increase in mid-autumn and a decline at the end of winter. Reproductive activity appeared in every month, with a maximum from February to June. Reproductively hyperactive females (simultaneously pregnant and nursing) appeared in every month except in January, with a first peak in March and a second lower peak in May-June. Litter size fluctuated between 1 and 7 leverets. The most frequent gestations involved 1 or 2 foetuses. The mean annual litter size was 2.08 and the average number of litters per productive female per year was estimated to be 3.48. The maximum productivity was recorded between March and May. The total annual production of young per adult female was estimated to be 7.21. The minimum annual survival rate of young was 27.91%. On the basis of these results we propose to maintain the limit of the hunting period between October and December. We discuss the relationship between the low young/adult ratio obtained and the hunting method used.

13

Morphological and genetical variability of Rubus hirtus (Waldst. & Kitt.) plants under partly open forest canopy

75%

Gazda A. , Szwagrzyk J. , Nybom H. , Werlemark G.

Polish Journal of Ecology

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2007

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tom Vol. 55, nr 1

49-55

EN

Blackberries growing in forests regenerate mainly in a vegetative way; however, detailed studies have shown substantial variability in performance of Rubus individuals. The main problem is if the differences among plants are genetically based, or are due to site heterogeneity? This study was aimed at determining 1) how large are the differences in performance of individual plants and how persistent they are during consecutive years, 2) how much of that variability can be explained by the local environmental conditions, especially the intensity of competition among plants, and whether the performance of individual plants is related to their genetic characteristics. In a partially cut mature beech forest in Western Carpathians 35 randomly chosen individuals of Rubus hirtus (Waldst. & Kitt.) were tagged and measured each year for 9 years. Ten largest and ten smallest individuals were selected for genetic analysis. Mean size of individual plants differed between consecutive growing seasons, but the overall size ranking was quite consistent throughout the entire period of study. Analysis of environmental variables: relative light intensity and local abundance of potential competitors explained about 24% of the differences in individual plant performance. In the genetic analysis the five primers were applied to analyse all 20 samples. The five primers produced 10 polymorphic bands, showing a high variability. Only a few samples displayed identical band patterns, indicating either vegetative propagation or apomictic origin. Distribution of the results of Spearman's rank correlation of plant size among genetically related individuals did not differ significantly from the distribution of rank correlation coefficients in the entire sample. In the analysed population genetical affinity did not seem to correlate withwith the performance of Rubus hirtus.

14

Age, growth, mortality and population structure of Polititapes aureus (Mollusca: Bivalvia) in the Gulf of Gabes, Tunisia

75%

Derbali A.

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2024

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tom Vol. 53, No. 2

102--110

EN

The population dynamics of Polititapes aureus from Tunisia were investigated monthly during a one-year period (2018). The possible future commercial benefits of the species as a significant resource of artisanal fisheries require better knowledge of its population dynamics. This study provides the first insight into population parameters by investigating its population structure, growth, mortality, and exploitation rate. Allometric relationships between body size and length were determined. The shell length/total weight ratio indicated a positive allometric growth and was expressed as TW = 0.0002 SL3.103. Length frequency data were analyzed to estimate population parameters using FiSAT ΙΙ software. P. aureus showed lower growth rate (K = 0.46 yr-1) and asymptotic length (L∞ = 38.80) compared to those obtained for other bivalve species (mean values: K = 0.61 and L∞ = 55.02). Longevity (Tmax) and the growth performance index (φ’) were 7.95 yr-1 and 2.84, respectively. Total mortality (Z) was estimated from the length-converted catch curve at 0.85 yr-1 and fishing mortality (F) at 0.03 yr-1. Both values of natural mortality (M = 0.82 yr-1) derived from bivalve literature and based on Pauly’s (1980) empirical equation (M = 0.83 yr-1) developed for fish were comparable. The most intensive growth occurred during the first three years. The data presented herein are crucial for appropriate fisheries management and conservation of clams.

15

Body size, condition, growth rate and parasite fauna of the invasive Perccottus glenii (Actinopterygii: Odontobutidae) from small watercourse in the Vistula River basin, Poland

75%

Czerniejewski P. , Linowska A. , Brysiewicz A. , Kasowska N.

Journal of Water and Land Development

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2020

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tom no. 44

33--42

EN

For the last few decades there have been reports not only of the occurrence of new invasive species of European watercourses, but also their increasing expansion. One of such species is the Amur sleeper (Perccottus glenii). The present work contains assessment of age and length distribution, condition as well as growth rate and analysis of the parasite fauna of the Amur sleeper from the waters of the Vistula River tributary in its middle course (the Habdziński Canal). During the catch performed in 2017 and 2019, the total of 177 Amur sleepers were recorded in the studied watercourse and a statistically significant sex structure disproportion was observed. Among the specimens caught in 2017 dominant were fishes with lengths of 50.1–60.1 mm whereas in 2019 the majority of the Amur sleeper specimens measured 30.1–50.0 mm. Six age groups were recorded among the caught fish with a clear prevalence of specimens aged 1+ (70.06%). The most frequently recorded parasite of P. glenii was non-quantifiable Trichodina rostrata ciliate for which the Amur sleeper from the Polish waters appeared to be a new host. Moreover, the presence of an acanthocephalan Acanthocephalus lucii, not recorded in Poland in this host before, was observed in the chyme. Also, accidental presence of larvae of the Opisthioglyphe ranae tremadote, which is a parasite typical of amphibians, was also recorded. Despite unfavourable habitat conditions and increased volumes of biogenic substances in the waters of the Habdziński Canal, the Amur sleeper found convenient conditions to reside in this small watercourse.

16

Analysis of genetic diversity of Ficus carica L. (Moraceae) collection using simple sequence repeat (SSR) markers

75%

Marcotuli I. , Mazzeo A. , Nigro D. , Giove L. , Giancaspro A. , Colasuonno P. , Prgomet Z. , Prgomet I. , Tarantino A. , Ferrara G. , Gadaleta A.

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2019

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tom 18

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nr 4

EN

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).

17

Remarks on the population structure of two Antarctic peracarid crustaceans: Eudorella splendida Zimmer, 1902 (Cumacea) and Nototanais antarcticus (Hodgson, 1902) (Tanaidacea)

75%

Błażewicz-Paszkowycz M. , Błażewicz-Paszkowycz M.

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18

Body size, condition, growth rate and parasite fauna of the invasive Perccottus glenii (Actinopterygii: Odontobutidae) from small watercourse in the Vistula River basin, Poland

75%

Czerniejewski P. , Linowska A. , Brysiewicz A. , Kasowska N. , Czerniejewski P. , Linowska A. , Brysiewicz A. , Kasowska N.

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nr 44

19

First data of age, condition, growth rate and diet of invasive Neogobius melanostomus (Pallas, 1814) in the Pomeranian Bay, Poland

75%

Rybczyk A. , Czerniejewski P. , Keszka S. , Janowicz M. , Brysiewicz A. , Wawrzyniak W.

Journal of Water and Land Development

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2020

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tom no. 47

142--149

EN

Round goby (Neogobius melanostomus (Pallas, 1814)) is an invasive species in the Oder River. In this study, age of 147 fish was determined using scales and otoliths, and the Fraser-Lee back-calculation method was used for population structure and theoretical length growth rates with 3 mathematical models of growth: von Bertalanffy, Ford–Walford and 2nd degree polynomial. Fish condition was determined using Fulton, Le Cren and Clark equations. Average total length and weight of fish was 162.00 mm and 83.00 g, respectively. Males were more abundant than females, representing 70% of the fish caught, and achieved greater total lengths and weights. Age 2+ dominated females and 3+ males age groups. Of the three mathematical models used to estimate fish growth, the 2nd degree polynomial model had the best fit to back-calculated lengths. Males had slightly higher growth rates than females in the first two years of life but comparable in subsequent years. The diet consisted of various benthic organisms that varied with fish age. The most frequently occurring food component was Dreissena polymorpha, which accounted for approximately 70% in the diet of fish with a body length greater than 191 mm.

20

Distribution, population structure and ecosystem effects of the invader Cercopagis pengoi (Polyphemoidea, Cladocera) in the Gulf of Finland and the open Baltic Sea

75%

Litvinchuk L. F. , Telesh I. V.

Oceanologia

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2006

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tom No. 48 (S)

243-257

EN

Spatial distribution, density, biomass, population structure, predation effects, and the influence of abiotic environmental characteristics (salinity, water temperature, transparency, and depth) on a population of the Ponto-Caspian invasive cladoceran Cercopagis pengoi (Ostroumov, 1891) were studied in the Gulf of Finland and the open Baltic Sea (August 1999 and 2004). In our study in 1999, this species was first recorded in plankton of open south-eastern Baltic waters. The age and sexual structure of the C. pengoi population were interrelated with population density. The strongest impact of C. pengoi predation on the pelagic community in the Gulf of Finland was registered at the stations where the percentage of C. pengoi in the total zooplankton biomass was the highest. The calculated impact values of C. pengoi exceeded those registered a decade ago, during the first years after Cercopagis had invaded the eastern Gulf of Finland.