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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Ovoviviparity in freshwater snails - advantages and disadvantages

100%
Jakubik B.
Folia Malacologica
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2016
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tom 24
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nr 1
2

Dynamics of chosen species of phyto- and zooplankton in a deep submontane dam reservoir in light of differing life strategies

100%
Wilk-Wozniak E., Pociecha A.
Oceanological and Hydrobiological Studies
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2007
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tom 36
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nr Suppl.1
3

Bryosoziologische Untersuchungen in Jordanien. 3. Lebensstrategienanalyse der terrestrischen und epilithischen Moosgesellschaften

100%
Frey W., Kurschner H.
Fragmenta Floristica et Geobotanica
|
1995
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tom 40
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nr 1
4

The life strategy and dynamics of selected species of phyto- and zooplankton in a dam reservoir during ;wet' and 'dry' years

100%
Pociecha A., Wilk-Wozniak E.
Polish Journal of Ecology
|
2006
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tom 54
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nr 1
The investigation was carried out during “dry” and “wet” (average: 478.6 mm and 624.7 mm, respectively) years in the Dobczyce Reservoir, which is located in a foothills area of southern Poland. The Reservoir covers 985 ha, has a volume of 108 × 10⁶ m³, a mean depth of 11 m and an average flushing rate of 2.9 yr⁻¹. Statistical analysis (ANOVA) showed that “dry” and “wet” years differed markedly as regards hydrological variables (water flow and flushing ratio). Among the physico-chemical variables, it was the concentration of NH₄-N that differed most in years of the different hydrological types. The main aim of the study was to check the life strategies and dynamics of selected species among the phyto- and zooplankton during the aforementioned “dry” and “wet” years. The assessment centered on changes in population densities for algal species of differing life strategies according to the Reynolds’ classification, particularly S-species (Microcystis aeruginosa (Kütz.) Kütz., Woronichinia naegeliana (Unger) Elenkin., R-species (Asterionella formosa Hass, Cyclotella sp.) and C/S-species (Ceratium hirundinella O. F. Müller) Bergh, Cryptomonas sp.). C species like Chlorella, Rhodomonas and Stephanodiscus hantzschii Grun. (in Cl. & Grunow), which were present in only small numbers, were not taken into consideration. No algal species presented any statistical differences in average population density between the studied years. Factors correlated (Pearson correlation) with the density of algae were found to be: flow, flushing ratio, transparency, turbidity and NO₃-N. Changes in the density of selected zooplankton species representing r-strategists (Bosmina longirostris (O. F. Müller, 1785), Brachionus angularis Gosse, 1851, Pompholyx sulcata Hudson, 1851) and K-strategists (Daphnia cucullata Sars, 1862, Daphnia longispina O. F. Müller, 1785, Eudiaptomus gracilis (Sars,1863) were also studied. The densities of Keratella cochlearis (Gosse, 1851) and Mesocylops leuckarti (Claus,1857) differed significantly between hydrological years. Physical environmental factors like flow, flushing ratio, transparency and turbidity were correlated with zooplankton density, as was shown by Pearson correlation coefficient. Our investigations did not confirm the hypothesis that R (phytoplankton) and r (zooplankton) species are favored by “wet” years, while species of types S (phytoplankton) and K (zooplankton) prefer the conditions present in “dry” years. Only the two zooplankton species characterized as different strategists (i.e. the r-selected Keratella cochlearis and K-selected Mesocyclops leuckarti) responded in significantly different ways to “wet” and “dry” years.
5

Cluster-based approach for identifying avian life-history groups for use in ecological monitoring

100%
Tworek S.
Polish Journal of Ecology
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2007
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tom 55
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nr 1
Almost ‘since ever’ ecologists have made attempts at the generalization of various site-specific, species-specific and timespecific situations, including different classifications of species, based on different principles and prepared for different purposes. This paper, presenting a conceptual model for selecting species of similar life-history pattern to other species and providing an example using birds as a model system, represents that current in the ecology. All bird species regarded as nesting in a given area of the mosaic landscape in southern Poland were described with respect to nine variables (nest type, nest location, food habits, place and way of foraging, migration status, number of broods, clutch size, incubation and fledging periods), grouped into 43 categories. Cluster analysis was then used to distinguish objectively species displaying similar life history traits and environmental adaptations into unique life-history ‘strategies’. The results of an exemplary analysis of variability in the density, domination, number of species and turnover rate in particular strategies, depending on the size of study plots, their structure, degree of isolation and the characteristic features of their surroundings, using regression and canonical correlation techniques, indicate the suitability of this approach to testing detailed hypotheses connected e.g. with studies on the response of species to different habitat conditions. The methods applied allow one to distinguish, in an objective way, the groups of species displaying similarities with respect to life history traits and environmental adaptations, in spite of the fact that the method of describing variables in cluster analysis may determine a different allocation of species to groups. A model, as described, could allow conservation principles to be developed for species of similar distribution, ecological feature or life history; especially for those species which face with population declines and for which no previous patterns have been established.
6
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Are all red algal parasites cut from the same cloth?

84%
Salomaki E. D., Lane C. E.
Acta Societatis Botanicorum Poloniae
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2014
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tom 83
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nr 4
Parasitism is a common life strategy throughout the eukaryotic tree of life. Many devastating human pathogens, including the causative agents of malaria and toxoplasmosis, have evolved from a photosynthetic ancestor. However, how an organism transitions from a photosynthetic to a parasitic life history strategy remains mostly unknown. This is largely because few systems present the opportunity to make meaningful comparisons between a parasite and a close free-living relative. Parasites have independently evolved dozens of times throughout the Florideophyceae (Rhodophyta), and often infect close relatives. The accepted evolutionary paradigm proposes that red algal parasites arise by first infecting a close relative and over time diversify and infect more distantly related species. This provides a natural evolutionary gradient of relationships between hosts and parasites that share a photosynthetic common ancestor. Elegant microscopic work in the late 20th century provided detailed insight into the infection cycle of red algal parasites and the cellular interactions between parasites and their hosts. Those studies led to the use of molecular work to further investigate the origins of the parasite organelles and reveal the evolutionary relationships between hosts and their parasites. Here we synthesize the research detailing the infection methods and cellular interactions between red algal parasites and their hosts. We offer an alternative hypothesis to the current dogma of red algal parasite evolution and propose that red algae can adopt a parasitic life strategy through multiple evolutionary pathways, including direct infection of distant relatives. Furthermore, we highlight potential directions for future research to further evaluate parasite evolution in red algae.
7
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

The effect of physico-chemical conditions on the shape of growth curves of Anodonta anatina (Linnaeus, 1758)

84%
Czarnoleski M., Dragosz-Kluska D., Labecka A. M., Muller T.
Folia Malacologica
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2012
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tom 20
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nr 1
8

Life strategies in salt marsh communities of the East Frisian North Sea Coast [North-Western Germany]

84%
Hensen I.
Fragmenta Floristica et Geobotanica
|
1998
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tom 43
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nr 2
9

Differentiation of the genus Callitriche L.

84%
Drapikowska M., Kupiec J., Szoszkiewicz K., Baczkiewicz A., Buczkowska K.
Seria Biologiczna. Uniwersytet im. Adama Mickiewicza w Poznaniu
|
2005
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tom 72
10
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Reproductive effort as an element of life strategy of Lythrum salicaria L. populations

84%
Czarnecka B., Franczak M., Nowak K.
Acta Agrobotanica
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2007
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tom 60
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nr 2
The aim of the study was to compare some life strategy traits of individuals of Purple Loosestrife Lythrum salicaria within three meadow populations existing under various habitat conditions. The study attempted to answer the following questions: Do different habitat conditions affect the biomass allocation between particular organs of individuals? Can the individuals belonging to different populations of the same species realise their own unique reproductive strategy, in other words, can their reproductive effort represent various levels? In the case of L. salicaria the reproductive effort, measured by the participation of inflorescence biomass in the biomass of aboveground parts of genets, exhibits similar values (14.2-15.1%) in all the study populations, despite their habitat conditions. This fact proves that at the population level, the reproductive effort is relatively stable. Great differences are visible in the case of particular individuals within each of the populations. Specific genets in a population, depending on the habitat microstructure and the biotic relations with other individuals both of their own and other species, may realise their own reproductive strategies, being a part of their life strategies.
11

A comparative study of the life strategies of two bacterial-feeding nematodes under laboratory conditions. I. Influence of culture conditions on selected life-history parameters of Acrobeloides nanus [De Man 1880] Anderson 1968 and Dolichorhabditis dolichura [Schneider 1866] Andrassy 1983

84%
Ilieva-Makulec K.
Polish Journal of Ecology
|
2001
|
tom 49
|
nr 1
12

A comparative study of the life strategies of two bacterial-feeding nematodes under laboratory conditions. II. Influence of the initial food level on the population dynamics of Acrobeloides nanus [De Man 1880] Anderson 1968 and Dolichorhabditis dolichura [Schneider 1866] Andrassy 1983

84%
Ilieva-Makulec K.
Polish Journal of Ecology
|
2001
|
tom 49
|
nr 2
13

Natural and anthropogenic coniferous forest communities of the Wapienica Valley and their role in maintaining populations of protected and rare plants

84%
Orczewska A.
Seria Biologiczna. Uniwersytet im. Adama Mickiewicza w Poznaniu
|
2004
|
tom 69
14

The life history of Carex cespitosa: consequences for population dynamics and vegetation succession. V. The life history and role of a C. cespitosa population in the process of succession on abandoned meadows - general discussion

84%
Brzosko E.
Polish Botanical Studies
|
1999
|
tom 14
15

Long-term changes in the phytoplankton of Lake Charzykowskie

67%
Wisniewska M., Luscinska M.
Oceanological and Hydrobiological Studies
|
2012
|
tom 41
|
nr 3
16

Patterns of variation in reproductive parameters in Eurasian lynx (Lynx lynx)

67%
Nilsen E. B., Linnell J. D. C., Odden J., Samelius G., Andren H.
Acta Theriologica
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2012
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tom 57
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nr 3
Detailed knowledge of the variation in demographic rates is central for our ability to understand the evolution of life history strategies and population dynamics, and to plan for the conservation of endangered species. We studied variation in reproductive output of 61 radio-collared Eurasian lynx females in four Scandinavian study sites spanning a total of 223 lynx-years. Specifically, we examined how the breeding proportion and litter size varied among study areas and age classes (2-year-old vs. >2-year-old females). In general, the breeding proportion varied between age classes and study sites, whereas we did not detect such variation in litter size. The lack of differences in litter sizes among age classes is at odds with most findings in large mammals, and we argue that this is because the level of prenatal investment is relatively low in felids compared to their substantial levels of postnatal care.
17

Life history strategies of fish: patterns in growth and lifespan of rudd Scardinius erythrophthalmus (L.) in Europe

67%
Tarkan A. S., Lappalainen J., Nurminen L., Horppila J.
Polish Journal of Ecology
|
2010
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tom 58
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nr 1
Variation in life history strategies of rudd Scardinius erythrophthalmus (L.) in Europe was evaluated based on published sources. The growth and lifespan were analysed as the main variables in life strategies of any fish. The results revealed that total length (TL) at age 1 year was correlated with latitude and faster growth during the first growing season leads to a shorter lifespan in Europe. Variation in length at age 1 year was more pronounced in southern (40–46°N: mean TL = 84.6 mm, SD = 27.2, n = 9) than in northern populations (49–61°N: mean TL = 46.4 mm, SD = 4.2, n = 10). Thus, rudd can show different life history strategies in southern populations whereas in northern populations these options are few.
18

Role of clonal integration in life strategy of sandy dune plant, Eremosparton songoricum (Litv.) Vass (Fabaceae): experimental approach

67%
Wang J.-C., Shi X., Yin L.-K., Zhang D.-Y.
Polish Journal of Ecology
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2011
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tom 59
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nr 3
A systematic knowledge of clonal integration is an important step in understanding the ecological implication of clonality. This study focuses on the performance of rhizomatous clonal plants under different situations and we proposed a hypothesis that clonal integration will significantly improve the disturbance and drought resistance ability and the competitive ability of Eremosparton songoricum. In 2009, the experiments were carried out in two natural populations. Rhizome was either severed (S) or not (I) in four treatments that include control (C), drought (D), disturbance (E), and competition (F). The biomass and the root-shoot ratio were compared in different experimental treatments. Under drought and disturbance treatments, the biomass of ramet with severed rhizome was significantly less than that of intact ramets, and both were lower than the samples under the control treatment. The differences in root-shoot ratio were opposite to the biomass in drought and disturbance treatments. The ramet biomass under the competition treatment had the same result as that under the drought and disturbance treatments. However, th e root-shoot ratio was highest in FS (competition treatment with severed rhizome) and lowest in FI (competition treatment with intact rhizome) under competition and control treatments. Our results suggest that clonal integration enhances the disturbance and drought resistance ability rather than the competitive ability of Eremosparton songoricum. This may be one of the various reasons why E. songoricum is distributed in sand dunes of droughty conditions with more disturbances but less competition. Integration proved to be important for the species occupying adverse patches. For E. songoricum, the existence of rhizome reduces the impact of environmental stress and improves the fitness in association with its location at the dune.
19

The diversity of the species composition and the life strategy of algae in peatbogs surrounding two dystrophic forest lakes

67%
Jacunska U.
International Journal of Ecohydrology and Hydrobiology
|
2003
|
tom 03
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nr 2
197-202
20

Effect of vegetation and management on occurrence of larvae and adults of generalist Maniola jurtina L. (Lepidoptera) in meadow habitats

67%
Kulfan J., Strbova E., Zach P.
Polish Journal of Ecology
|
2012
|
tom 60
|
nr 3
Larvae and adults of some generalist insect species co-occur in identical habitats whereas adults and larvae of other generalist species do not co-occur and occupy different habitats. The Meadow brown, Maniola jurtina (L.) (Lepidoptera: Nymphalidae), is common and widely distributed in Europe where it is considered a habitat generalist. As knowledge about the occurrence of the larvae of the Meadow brown is scarce (different and more difficult methods are needed to collect larvae compared to adults) a complex assessment of the life strategy of this generalist is limited. We addressed here the question as to whether the adults and larvae of the Meadow brown co-occurred in the same habitats and how they depended on the type of grassland vegetation and habitat management. We expected co-occurrence of adults and larvae and similar effects of habitat management on them. We selected four habitat types belonging to the alliance Arrhenatherion elatioris W. Koch 1926, which form mosaic patterns in the rural landscape of central Slovakia: (1) extensive meadows mown once a year, (2) extensive meadows mown twice a year, (3) abandoned meadows, and (4) ecotones between deciduous forests and meadows mown once a year. Adults were counted in each habitat on seven transects 50 m long (in seven replicates) during the summer of 2003, 2004 and 2005. Larvae were collected in each habitat on 10 transects 50 m long (ten replicates) by sweeping vegetation (60 sweepings per transect) at night in May 2005 and 2006. Both adults and larvae occurred in all the mentioned types of habitats. A high abundance of adults and larvae was recorded in extensive meadows mown once a year and in ecotones. The lowest abundance of adults and larvae was found in abandoned meadows. The differences between abandoned meadows and ecotones (in the case of adults) and between abandoned meadows and extensive meadows mown once a year (in the case of larvae) were significant in all study years (P <0.05; multiple comparisons, K-W ANOVA). In the abandoned meadows the number of adults and larvae (median) was approximately 2 to 5 and 5 to 25 times lower than in the preferred habitats, respectively. Maximum numbers of both adults and larvae per single recording/sampling date were obtained in extensive meadows mown once a year; that is 185 adults in a transect 350 m long and 4 m wide and 267 larvae in the transect 500 m long (600 sweepings). Hence, similar to adults, larvae tend to be habitat generalists. Our results have confirmed the ”advantageous“ life strategy of M. jurtina which enables the species to adapt to a wide range of habitats, including those under strong pressure from humans. Comparing management practices in the study habitats, meadows which are mowed once a year were the most appropriate alternative for this species.
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