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Ważniejsze metody estymacji w statystyce małych obszarów

100%

Kubacki J.

Wiadomości Statystyczne

1997

tom 42

nr 05

Age structure and reproduction rates of the ring-necked pheasant (Phasianus colchicus L.) population in agriculture landscape (Czech Republic)

100%

Zíka T. , Šálek M. , Holá M. , Hanzal V. , Hart V. , Kušta T. , Ježek M.

Polish Journal of Ecology

2014

tom Vol. 62, nr 4

751--759

Detailed knowledge of demographic parameters (such as age structure and reproduction rates) is crucial for guiding conservation and management decisions regarding wildlife populations. Such parameters of wild ring-necked pheasant populations in the current agricultural landscape remain very poorly described. We researched age structure and reproduction rates of predominantly wild populations of the ring-necked pheasant (Phasianus colchicus L.) across the intensively managed agricultural landscape of the Czech Republic. The study area is influenced only marginally by hand-reared pheasants (i.e. as shown by comparison of the average number of released individuals in the study area: 0.3 ♂/yr/1km2 and 0.9 ♀/yr/1km2 and average number of released individuals and harvested in the study area: 8.6 ♂/yr/1km2) and there is a long-term huntable pheasant population. To determine the age of individuals, we used proximal primary feather shaft diameters of 1487 feather samples from males hunted between 2009 and 2011. Moreover, we evaluated the age structure of females as well as both sexes together based on the sex ratio and annual game census. We found a relatively high proportion of adults in the population in comparison with other studies. However, the number of adults decreased throughout the years: 2009 (♂ 44.7%; ♀ 69.5%; ♂♀ 60.7%), 2010 (♂ 35.2%; ♀ 61.3%; ♂♀ 51.5%), 2011 (♂ 29.8%; ♀ 57.4%; ♂♀ 47.0%). The decrease of adults went hand in hand with increase of juveniles and reproduction rates of the study population: 2009 (♂ 124%; ♀ 44%; ♂♀ 65%), 2010 (♂ 184%; ♀ 63%; ♂♀ 94%), 2011 (♂ 236%; ♀ 74%; ♂♀ 113%). Only males were hunted in the study area so we determined higher proportions of females in population for all years. This is the main reason why the reproduction rate of females was lower in percentage expression. Generally, our results showed lower productivity of pheasants in the Czech agricultural landscape in comparison with earlier published studies conducted in the US and UK. However, these studies were published many years ago and thus do not reflect the actual environmental conditions and changes which took place recently (i.e. agricultural intensification).

System komputerowy wspomagajacy wyznaczanie parametrow demograficznych i analize populacji owadow

80%

Kozlowski R. J. , Niedbala G. , Durak R. , Borowiak-Sobkowiak B.

Technika Rolnicza Ogrodnicza Leśna

2010

nr 04

16-18

Celem pracy było opracowanie uniwersalnej metody komputerowego wyznaczenia parametrów demograficznych owadów, zastosowanej w niniejszej pracy do badań populacji mszyc (Aphidoidea) na przykładzie Rhopalosiphoninus latysiphon. Opracowany system komputerowy wykorzystuje złożone algorytmy obliczeniowe do wyznaczenia podstawowych parametrów demograficznych, tj. wrodzonego tempa wzrostu populacji, tempa reprodukcji netto, tempa zwielokrotnienia liczebności populacji, średniego czasu rozwoju pokolenia oraz czasu podwojenia się populacji. Algorytmy te zaimplementowane zostały w postaci jednostanowiskowej aplikacji komputerowej. Zastosowanie nowoczesnych technologii informatycznych pozwoliło na dokładniejsze wyznaczenie ww. parametrów niż metodami stosowanymi dotychczas. W znacznym stopniu uległ też skróceniu czas przeprowadzenia analizy.

The aim of the work was to develop universal computer-aided method for estimation of demographic parameters for any insect population. This method was applied in this work to study a population of aphids (Aphidoidea): Rhopalosiphoninus latysiphon. The developed computer system uses a complex computational algorithms to set the basic demographic parameters such as: intrinsic rate of increase, net reproductive value, finite rate of increase, mean generation time, population doubling time. These algorithms have been implemented as a single user computer applications. The use of modern computer technologies allowed for more accurate determination of the parameters than methods applied so far. The time of analysis was also shortened.

Wybrane elementy bionomii i parametry demograficzne anholocyklicznego gatunku Myzus ascalonicus Doncaster, 1946 (Hemiptera: Aphididae)

60%

Durak R. , Borowiak-Sobkowiak B.

Wiadomości Entomologiczne

2014

tom 33

nr 4

Myzus ascalonicus DONCASTER, 1946 is an anholocyclic and polyphagous species. It may infest plants of over 20 families, most frequently Alliaceae, Caryophyllaceae, Compositae, Brassicaceae, Liliaceae and Rosaceae. It is almost worldwide distributed, also in Subantarctic regions. In winter in Poland it can continue developing by infesting greenhouse and house plants. The study was conducted in 2009–2010. The paper defines the length of prereproduction, reproduction and postreproduction stages of wingless M. ascalonicus females developing in winter. Also the total lifespan and fecundity of females was calculated along with demographic parameters of M. ascalonicus population.