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Seasonal population dynamics of the monogeneans Quadriacanthus kobinensis parasitising Clarias fuscus in Pearl River, China

that of Lim (1998) in Southeast Asia. We haven′t calculated the statistical parameters for G. fusci because Q. kobinensis was absolutely predominant .There were only 93 specimens of G. fusci collected and it was far less than the number of Q. kobinensis . The seasonal population dynamics of a monogenean is related to complex environmental parameters especially water temperature ( Chubb,1977 ) as e.g., MO (1992) found Gyrodactylus salaris through most of the year except 2-3 months when temperature had fallen to almost 0 °C; Jansen & Bakke (1993) found

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Quantifying whether different demographic models produce incongruent results on population dynamics of two long-term studied rodent species

populations. Acta Theriologica, 20, 23-40. Begon, M. (1983) Abuses of mathematical methods in ecology: applications of Jolly’s capture-recapture method. Oikos, 40, 155-158. Boonstra, R. & Krebs, C.J. (2006) Population limitation of the northern red-backed vole in the boreal forests of northern Canada. Journal of Animal Ecology, 75, 1269-1284. Boonstra, R. & Krebs, C.J. (2012) Population dynamics of red-back voles (Myodes) in North America. Oecologia, 168, 601-620. Bujalska, G. (1975) Reproduction and mortality

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Population Dynamics of the Roe Deer, Capreolus Capreolus, and the Red Deer, Cervus Elaphus (Artiodactyla, Cervidae), in the Mountain Crimea

. Moscow, 1-421 [In Russian]. Odum, Eu. 1975. Fundamentals of Ecology. Mir, Moscow, 1-740 [In Russian]. Polyakov, I. Y. 1949. Th e Th eoretical essence of the doctrine of periodicity of mass reproductions of voles and mice. Journal of General Biol., 10, 3, 249-260 [In Russian]. Severtsov, S. A. 1941. Population dynamics and adaptive evolution of animals. Publishing House of the Academy of Sciences of the USSR, Moscow, Leningrad, 1-316 [In Russian]. Folitarek, S. S. 1980. Th eoretical bases of biotechnics and

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Some bioecological aspects of the rose aphid, Macrosiphum rosae (Hemiptera: Aphididae) and its natural enemies

mutualists. Ecology 95(6), 1479-1484. [27] Brabec, M., Honěk, A., Pekár, S., Martinková, Z. (2014), Population dynamics of aphids on cereals: Digging in the time-series data to reveal population regulation caused by temperature. PLoS ONE 9(9), e106228. [28] Braendle, C., Davis, G. K., Brisson, J. A., Stern, D. L. (2006), Wing dimorphism in aphids. Heredity 97(3), 192-199. [29] Brisson, J. A. (2010), Aphid wing dimorphisms: linking environmental and genetic control of trait variation. Philosophical Transactions of the Royal

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Seasonal population dynamics of the monogeneans Pseudorhabdosynochus coioidesis and P. serrani on wild versus cultured groupers in Daya Bay, South China Sea

[1] Appleby, C. (1996): Population dynamics of Gyrodactylus sp. (Monogenea) infecting the sand goby in the Oslo Fjord, Norway. J. Fish Biol., 49: 402–410 [2] Bakke, T. A., Jansen, P. A., Brabrand, A. (1990): Susceptibility and resistance of brook lamprey, Lampetra planeri (Bloch), roach, Rutilus rutilus (L.) and perch, Perca fluviatilis L. to Gyrodactylus salaris Malmberg (Monogenea). Fauna Norv., Ser. A, 11: 23–26 [3] Bakke, T. A., Sharp, L. A. (1990): Susceptibility and resistance of

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Population dynamics of Pulsatilla patens (L.) Mill. in a new locality in Poland

Abstract

A new locality of Pulsatilla patens (L.) Mill. in the Wyszków-Jegiel Forest District, in the southern part of Puszcza Biała (ATPOL EC79) is described. This locality is situated on an escarpment, at the edge of Peucedano-Pinetum fresh pine forest with elements of Serratulo-Pinetum mixed pine forest and Potentillo albae-Quercetum steppe oak forest. Good light conditions prevail in the place of plant occurrence. Studies carried out in 2008-2015 showed an increasing trend of P. patens population, though, recently, this population seems to be stable. The number of species accompanying the pasque-flower also increased in this time period. It was found based on the analysis of flora directly neighbouring the clumps of the pasque-flower. During 7 years, the number of taxa increased by 31.5% on plot I and by 25% on plot II. In the years 2011-2013, the pasque-flower was represented both by flowering (1-2) and vegetative individuals. Afterwards, the plant was present only in vegetative stage. The number of its leaves varied in time. The highest number of leaves - 14 per individual - was noted in 2014, and the lowest number (1) - in 2012. The reason for a decline in the number of plant clumps in the site Dalekie and, at the same time, the greatest threat was the excavation of sand from the escarpment. In 2012, this escarpment slid down and several clumps of the pasque-flower were destroyed. Forest management and digging up by wild boars were additional factors limiting the population. To preserve the site of P. patens, measures of active protection should be applied.

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Habitat demands and population characteristics of the rare plant species Gladiolus imbricatus L. in the Frenštát region (NE Moravia, the Czech Republic)

-173. Kostrakiewicz K. & Wróblewska A. (2008): Low genetic variation in subpopulations of an endangered clonal plant Iris sibirica in southern Poland. - Ann. Bot. Fennici, 45: 186-194. Krátká M. (in litt.): Populační dynamika vstavače kukačky ( Orchis morio L.) na vybraných lokalitách střední Moravy. (Diplomová práce). [Population dynamics of plant species Orchis morio on selected sites of middle Moravia (the Czech Republic)]. (Diploma thesis). Faculty of Science, Palacký University in Olomouc, 2006, Olomouc, 50 pp. Kubát K. et

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Stochastic Modelling for Dynamics of Interacting Populations

Abstract

The paper deals with a mathematical model for two interacting populations. Under the assumption of fast stochastic contacting of populations, we derive stochastic Poisson-type differential equations with a small parameter and propose an approximative algorithm for quantitative analysis of population dynamics that consists of two steps. First, we derive an ordinary differential equation for mean value of each population growth and analyse the average asymptotic population behaviour. Then, applying diffusion approximation procedure, we derive a stochastic Ito differential equation for small random deviations on the average motion in a form of a linear non-homogeneous Ito stochastic differential equation and analyse the probabilistic characteristics of the Gaussian process given by this equation.

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On Nonlinear Waves in the Spatio-Temporal Dynamics of Interacting Populations

Nonlinear PDEs: The Role of the Simplest Equation. Commun Nonlinear Sci Numer Simulat, 16 (2011), 4215-4231. [15] Vitanov, N. K., Z. I. Dimitrova. Application of the Method of Simplest Equation for Obtaining Exact travelling-wave Solutions for Two Classes of Model PDEs from Ecology and Population Dynamics. Commun Nonlinear Sci Numer Simulat, 15 (2010), 2836-2845. [16] Dimitrova, Z. I., N. K. Vitanov. Dynamical Consequences of Adaptation of Growth Rates in a System of Three Competing Populations. J. Phys. A: Math Gen., 34 (2001), 7459-7473.

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The population status of elk (Alces alces) in Ukraine

Stan populacji łosia na Ukrainie

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