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  1. 7 Polish Journal of Ecology

  2. 5 Oceanologia

  3. 3 Polish Botanical Studies

  4. 2 Archives of Polish Fisheries

  5. 2 Folia Malacologica

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  1. 3 Brzosko E.

  2. 3 Jakubik B.

  3. 2 Barszcz A.

  4. 2 Jumawan J. C.

  5. 2 Seronay R. A.

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  1. 2 2021

  2. 3 2020

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

Size structure and gonad characterization of Gari elongata (Lamarck 1818) from the coastal areas of Hinatuan, Surigao Del Sur, Philippines

100%
Buenaflor E. M., Seronay R. A., Jumawan J. C.
International Letters of Natural Sciences
|
2020
|
tom 80
2
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

The size structure of the Mesodinium rubrum population in the Gdańsk Basin

86%
Rychert K.
Oceanologia
|
2004
|
tom 46
|
nr 3
The ciliate Mesodinium rubrum Lohmann 1908 (= Myrionecta rubra Jankowski 1976) is an important phototrophic organismin the Gdańsk Basin. In June 2002 the vertical distribution and size structure of the M. rubrum population were studied. Its presence was generally observed in the whole water column (one exception was the anoxic near-bottom zone in the Gdańsk Deep) at all stations studied. Maximum abundance (18 300 cells dm−3) was recorded at 26 m depth at the station located in the inner Gulf of Gdańsk. Analysis of the size structure of the counted organisms demonstrated the co-existence of small and large cells of M. rubrum in the upper layer of the water column and a gradual increase with depth of the prevalence of large specimens. This shows that at least two forms of M. rubrum exist in the region studied. Deep migrations are probably undertaken only by relatively large organisms.
3

The effect of vegetation character on abundance and structure of subpopulations of rare herb species Gentiana pneumonanthe L.

72%
Kostrakiewicz-Gieralt K.
Polish Journal of Ecology
|
2013
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tom 61
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nr 1
During the 20th century in Central and Eastern Europe, traditional agricultural management was either heavily intensified or abandoned due to socio-economic reasons. The land abandonment led to subsequent secondary succession reverted many wet meadows into Phragmites swamps, Salix or Alnus thickets, as well as woodlands. Therefore, the understanding of changes in abundance and structure of populations in the process of succession has become very important especially for rare and endangered species. In Poland one of strictly protected plant is Gentiana pneumonanthe L. It is a nonclonal, long-lived, iteroparous plant consisted of numerous vegetative and generative stems, bearing 1–25 flowers per year. The investigations of abundance and structure of subpopulations of Gentiana pneumonanthe were conducted in the years 2009– 2011 in abandoned Molinietum caeruleae meadows dominated by low-stature species (Patch I), prevailed by tall grasses (Patch II), willows (Patch III), as well as partly overgrown by shrubs and trees (Patch IV). The average height of vegetation cover achieved from 65.3 cm (Patch I), via 85.8 cm (Patch II) and 94.0 cm (Patch III), to 142.7 cm (Patch IV). The gradually decline of abundance of Gentiana pneumonathe subpopulations and increased trend toward their senilization along the gradient of vegetation height might be due to successional closure of plant cover, preventing seedling recruitment. The total number of stems per individual and length of vegetative stems decreased with augmentation of neighbouring plants dimensions, whereas the height of generative stems, as well as flower and fruit production presented inversed trend. The greatest dimensions of capsules found in patch dominated by small meadow species might be due to greater availability of solar radiation. The conditions of studied subpopulations decrease gradually from patch dominated by small meadow species, via sites prevailed by grasses and willows, to place overgrown by shrubs and trees. Although obvious differences in abundance and structure of individuals, the prospects of all observed populations are poor, especially that patches are not subjected active protection.
4
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Biometrical analysis of selected characters of Viviparus viviparus from the lower Narew River

72%
Jakubik B.
Folia Malacologica
|
1999
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tom 07
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nr 4
5

Multi-mesh gillnets in investigations of the ichthyofauna of different littoral habitats in a deep lake

72%
Kapusta A., Czarkowski T.
Electronic Journal of Polish Agricultural Universities. Series Fisheries
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2007
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tom 10
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nr 4
6

Significance of stump-sprouting for the population size structure and spatial distribution patterns of endangered species, Magnolia cylindrica

72%
Li J., Wu Y., Wu T., Cao L., Chen J., Qiu Z., Zhang Y., Xu G., Zhang J., Liu P.
Polish Journal of Ecology
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2017
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tom 65
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nr 2
Magnolia cylindrica Wils. is one of the third most-protected wild plants in China. To describe the size structure and dynamics of its population, field data were obtained from eight newly established sites, using a contiguous grid quadrate method in Jiulong Mountain of East China. The population size structure and spatial distribution pattern were discussed based on a theoretical distribution model and assembling intensity index. The population size structure showed a declining trend because of the lack of seedlings. The number of stump-sprouting, size class III (sapling trees) individuals was large enough to make up for the shortage of small seedlings and the complete regeneration of populations through sprouting. The distributions of M. cylindrica, both seedling populations (Group A) and overall populations (Group B), were mostly clumped. The spatial pattern intensities of the populations at different stages (mainly small trees, middle trees, and big trees) were higher for Group A than those for Group B. The two groups have the same tendency in that the pattern intensity declined from small trees to the larger ones. Group A and Group B differed in spatial pattern: small and middle trees were randomly distributed in seedling populations, but aggregated in overall populations. The populations of M. cylindrica (both group A and B) were characterized by the pattern scale between 16 to 32 m2, measured by Greig-Smith and Kershaw methods. These results suggest that sprouting should be seriously considered in population rehabilitation and forest tending management and the area of forest tending management should be close to the maximum intensity.
7

Formation and dynamics of the metapopulation of Senecio rivularis (Waldst. and Kit.) DC. (Asteraceae) at the limit of its geographical range: where, when, by what means?

72%
Czarnecka B.
Polish Journal of Ecology
|
2011
|
tom 59
|
nr 2
In the studies on the metapopulation system two aspects are important: cognitive and practical. The former indicates that a metapopulation is a demographic structure of a higher level than coenotic or local populations and aims at recognition of relations between particular populations of a given species. The practical aspect reflects the issues of the dynamics and/or the extinction rate in particular populations and indicates potential habitats which can be colonized. The study of the Senecio rivularis metapopulation is created by relatively abundant population of ragwort in the Roztocze Highlands, Roztocze National Park, south-eastern Poland, recognized as the source population and three other called marginal or sink populations as well as potentially suitable habitats which are distributed as islands in adjacent hydrogenic areas. The distances between particular populations range from 1.3 to 6.5 km. As a long-lived, iteroparous rhizomatous clonal plant, insect-pollinated and anemochoric one, so having adaptations both for ‘escape in time’ and ‘escape in space’, S. rivularis may be treated as the model object of the study on the metapopulation level. The following hypotheses were put forward: (1) the spatial pattern, size and life-stage structures of particular populations reflect the time of their origin in the meta-system; (2) hydrochory is a complementary or alternative way of migration of anemochoric diaspores; (3) local watercourses and hydro-technical activity affect the formation and dynamics of S. rivularis metapopulation. The multi-aspect studies of the source population were conducted in the years 1987–2007. They aimed to establish the density, spatial pattern and life-stage structure of the S. rivularis population, both at a large scale, i.e. in the whole population (three times) and at a small scale, i.e. on the level of three particular clumps (four times). The size structure of generative genets and ramets in the whole population was elaborated five times. In the greatest of the other populations in the meta-system, the size structure was elaborated twice (2002, 2007) while the study of spatial and life-stage structures was done only once, in the first period, because of the disturbance of a greater part of the population in the next years. In the two remaining localities all plants were counted thanks to small abundance of the populations. Considerable changes in the spatial organization and life-stage structure of genets in the source and sink populations exhibited that colonization in the meta-system of S. rivularis proceeds in accordance with an island model of the ‘stepping stone’ type, downstream the river. Renaturalization of water relations of river catchment areas and construction of the so-called small retention objects affect the formation and dynamics of S. rivularis metapopulation which reflects at least some dynamics phases observed at the level of the source population: progressive, stable, fluctuation and/or regressive, and extinction phases. Knowledge of the density, life-stage and size structures of plants in a population facilitates a highly reliable determination of the development phase of a given local population in the meta-system and prognosis of its future.
8

Analysis of age and size structure of chain saws used in the selected regions of Poland

72%
Zychowicz W.
Annals of Warsaw University of Life Sciences - SGGW. Agriculture
|
2009
|
nr 53 Agric.Forest Eng.
55-61
9
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Microplankton size structure induced by a warm-core eddy in the Western Bay of Bengal: Role of Trichodesmium abundance

72%
Chinnadurai K., Retnamma J., Nagarathinam A., Subramanian P. R., Singaram P., Shoba S.
Oceanologia
|
2021
|
tom 63
|
nr 3
10
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Phytoplankton size structure and species composition as an indicator of trophic status in transitional ecosystems: the case study of a Mediterranean fjord-like karstic bay

72%
Bosak S., Silovic T., Ljubesic Z., Kuspilic G., Pestoric B., Krivokapic S., Vilicic D.
Oceanologia
|
2012
|
tom 54
|
nr 2
The species composition and size-structure of the phytoplankton community in the Boka Kotorska Bay (SE Adriatic Sea) were analysed with respect to abundance and carbon biomass, together with the physico-chemical parameters, with the aim of evaluating the predefined oligo-mesotrophic status of this transitional water ecosystem. Three stations located in the inner part of the Bay were sampled with seasonal frequency in 2008/2009. Picophytoplankton cells were counted using flow cytometry; nanophytoplankton and microphytoplankton were identified and counted by light microscopy. The relative importance of the picoplankton in the Bay, in terms of both abundance and biomass, during all the investigated seasons emphasized their significance in the phytoplankton community. Picocyanobacteria (Synechococcus) constituted a significant part of the summer assemblages with regard to both abundance (up to 3.38 × 108 cells L−1) and carbon biomass (up to 73% of total phytoplankton carbon). The contribution of the nanophytoplankton was found to be generally low (<20% of the total phytoplankton carbon) in all seasons, and was dominated by autotrophic/mixotrophic flagellates. Species with a preference towards nutrient-enriched conditions, like the diatom Skeletonema marinoi, dominated the microphytoplankton fraction. S. marinoi was the most abundant in spring/winter (up to 2.86×106 cells L−1) above the halocline (making a 96% contribution to the microphytoplankton). The potentially toxin-producing diatom Pseudo-nitzschia pseudodelicatissima was recorded at abundances greater than 105 cells L−1, together with Thalassionema frauenfeldii, as well as the dinoflagellates Prorocentrum micans and the potentially harmful P. minimum. The higher values of phytoplankton biomass and the dominance of phytoplankton species or groups with preferences for nutrient-enriched conditions appear to be consistent with the oligo-mesotrophic status of this specific ecosystem.
11

The dependency of the quality and size structure and of the value of timber on the origin and age of stands

72%
Barszcz A.
Electronic Journal of Polish Agricultural Universities. Series: Forestry
|
2004
|
tom 07
|
nr 2
12
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Reproductive phenology and size structure characteristics of Hypseleotris agilis (Herre, 1927) in Lake Mainit, Philippines

72%
Jumawan J. C., Hidalgo P. M. P., Seronay R. A.
International Letters of Natural Sciences
|
2020
|
tom 80
13

Various reproductive strategies of two species of Oligochaeta: Limnodrilus hoffmeisteri and Tubifex tubifex

72%
Zbikowski J.
Oceanological and Hydrobiological Studies
|
2007
|
tom 36
|
nr Suppl.4
14

The life history of Carex cespitosa: consequences for population dynamics and vegetation succession. IV. Population dynamics of C. cespitosa in the process of succession

72%
Brzosko E.
Polish Botanical Studies
|
1999
|
tom 14
15

The life history of Carex cespitosa: consequences for population dynamics and vegetation succession. II. Population structure of C. cespitosa during the course of succession

72%
Brzosko E.
Polish Botanical Studies
|
1999
|
tom 14
16

The condition of housing in Poland

58%
Kornilowicz J.
Problemy Rozwoju Miast
|
2010
|
tom 07
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nr 1
The condition of housing in Poland¹ as per 2007 data was presented here on the basis of the following: 1) housing stock condition, 2) flat occupancy rates, 3) housing development, 4) repair needs, with certain IUD research results concerning 19 selected cities in Poland.
17
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Population characteristics of Viviparus (Mollusca: Gastropoda) in Ukraine

58%
Uvaeva O. I.
Folia Malacologica
|
2012
|
tom 20
|
nr 1
18

The influence of bedrock type on spruce timber quality in mountainous forest stands

58%
Barszcz A., Rutkowska L.
Zeszyty Naukowe Akademii Rolniczej w Krakowie. Sesja Naukowa
|
2005
|
tom 91
403-408
19
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Characterization of phytoplankton size-structure based productivity, pigment complexes (HPLC/CHEMTAX) and species composition in the Cochin estuary (Southwest coast of India): special emphasis on diatoms

58%
Paul M., Valappan M. N., Nanappan U., Gopinath V., Velloth R. T., Rajendran A., Nair M., Peariya A.
Oceanologia
|
2021
|
tom 63
|
nr 4
20

Planktonic ciliates of the Neva Estuary (Baltic Sea): community structure and spatial distribution

58%
Mironova E., Telesh I., Skarlato S.
Acta Protozoologica
|
2013
|
tom 52
|
nr 1
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