Wyniki wyszukiwania - Biblioteka Nauki

1

Biodiversity and energy transfer to top trophic levels in two contrasting Arctic fjords

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Węsławski J. M. , Kwaśniewski S. , Stempniewicz L. , Błachowiak-Samołyk K. , Węsławski J. M. , Kwaśniewski S. , Stempniewicz L. , Błachowiak-Samołyk K.

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2

Factors describing the distribution of the zooplankton community in the Gulf of Finland in the context of interactions between native and introduced predatory cladocerans

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Pollumäe A. , Kotta J.

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tom No. 49 (2)

277-290

EN

Mesozooplankton communities were studied monthly at six sites in the Gulf of Finland during six ice-free seasons. The abundances of different zooplankton taxa were related to temperature, salinity, eutrophication level (total nitrogen and phosphorus), phytoplankton Chl a and density of predatory cladocerans, including the non-indigenous Cercopagis pengoi and the native Leptodora kindtii. The results indicated that variability in the zooplankton communities was correlated not only with predation by mesozooplankton but also with bottom-up effects. Predation by the non-indigenous C. pengoi may significantly affect the dynamics of Cladocera and Rotatoria in the Gulf of Finland during the summer season.

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Long term effects of liming in a humic lake : ecosystem processes, biodiversity, food web functioning (Lake Flosek, Masurian Lakeland, Poland)

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Hillbricht-Ilkowska A. , Dusoge K. , Ejsmont-Karabin J. , Jasser I. , Kufel I. , Ozimek T. , Rybak J. I. , Rzepecki M. , Węgleńska T.

Polish Journal of Ecology

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1998

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tom Vol. 46, no 4

347-415

EN

The chemical composition of water and bottom sediments, productivity and decomposition rates as well as the biodiversity and food web functioning (organic suspension, edible algae, bacterio-detrivores, herbivores, grazers, predators) in plankton and benthos were analysed in humuc, weakly acid, mid-forest lake surrounded by peatmoss Sphagnum (Lake Flosek, Masurian Lakeland, Poland) before and 1-4 and 20-23 years after application of powdered lime. Calcium content and pH in water and sediment raised permanently. High water quality variables were main-tained after liming (low production, algal biomass, chlorophyll and nutrient concentration, low release rate of phosphorus from the sediments). Decomposition rate of organic matter increased significantly. The species richness and diversity of algae, rotifers, crustacean and benthic invertebrates increased at least twice as well as the abundance of bacterio-detrivores in plankton (small rotifers) and benthos (chironomids) and herbivores (big daphnids, diaptomids) in plankton. The distinct succession in species composition was observed in many taxa. The predators like larvae of Chaoborus, cyclopids and predatory rotifers became very abundant after 20 years since liming. No evident peatmoss mat spreading over the lake table has been observed since liming but also no detrimental effect on peatmoss surrounding the lake. It was concluded that the moderate liming affects first of all the biodiversity of lake biota then it stimulates the mobilisation of the lake which eventually lead to the greater and more stable complexity of trophic links. The species-rich and top-down controlled food web was installed in the limed lake without interfering with high quality of lake waters (low-productive, high-transparent) and unique, natural values of its surroundings.However, a slight increase in nutrient concentration after 22-23 years was observed which could be related to more efficient recycling mechanism in lake (due to abundant big components in plankton and benthos) or to eutrophication.

4

Notes on fishes in Hornsund fjord area (Spitsbergen)

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Węsławski J. M. , Kuliński W. , Węsławski J. M. , Kuliński W.

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nr 2

5

Use of stable isotopes to delineate amphipod trophic status in Antarctic food webs

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Nyssen F. , Brey T. , Lepoint G. , Bouquegneau J. M. , De Broyer C. , Dauby P.

Polskie Archiwum Hydrobiologii

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2000

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tom 47

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nr 3-4

6

Role of Nanoplanktons in Marine food-webs

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Das N. , Pandey A.

International Letters of Natural Sciences

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2015

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tom 43

EN

Nanoplanktons are ubiquitous protozoan zooplankton in a size range of 2 to 20 μm, play key ecological roles in aquatic ecosystems. Heterotrophic nanoflagellates are distributed through the continental shelf and margin area of the oceans as well as deep-sea. These organisms contribute significantly to the total living biomass within these systems, serve as the major top–down control on bacterial assemblages, and are an important source of mortality for microalgae and other heterotrophic nanoflagellates. From many recent studies, it is generally accepted that HNF is one of the most important bacterial consumers. They also function as important remineralizers of organic matter and nutrients in aquatic systems. In accordance with these important ecological roles, heterotrophic nanoflagellates have been the subject of considerable study both in the field and laboratory.

7

Prey abundance supporting unusual water mite (Acari: Hydrachnidia) community in a sublacustrine spring and tributary river

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Pozojevic I. , Ternjej I. , Mihaljewic Z. , Gottstein S. , Vickovic N. , Doric V. , Rumisek M.

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2018

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tom 25

8

Trophic connectivity between intertidal and offshore food webs in Mirs Bay, China

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Ning J. , Du F. , Wang X. , Wang L. , Li Y.

Oceanologia

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2019

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tom 61

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nr 2

9

Leaves as “crackers”, biofilm as “peanut butter”: Exploratory use of stable isotopes as evidence for microbial pathways in detrital food webs

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France R. L.

Oceanological and Hydrobiological Studies

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2011

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tom 40

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nr 4

10

Microbial plankton communities in the coastal Southeastern Black Sea: biomass, composition and trophic interactions

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Aytan U. , Feyzioglu A. M. , Valente A. , Agirbas E. , Fileman E. S.

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tom 60

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nr 2

11

Biomass distribution and dynamics and food web relations in psammon community of a eutrophic lake

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Kalinowska K. , Ejsmont-Karabin J. , Gorelysheva Z. , Rybak J. I.

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tom 60

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nr 3

EN

Organisms living in submerged sand along the shore and below the water’s edge in freshwater lake beaches create community called hydropsammon (see Fig. 1 in Preface). Trophic relations between psammon food web components are essential in energy flow, nutrient cycling and functioning of aquatic environments. The seasonal changes in algal, bacterial, nanoflagellate, ciliate, rotifer and crustacean biomass were investigated in hydroarenal (submerged sand) of the eutrophic Lake Mikołajskie (Poland). Sampling cores were taken once or twice a month since April till October 2005 from three layers: adjacent water layer (AWL), layer of water and sand from the transitory level (EPIH – epihydroarenal) and slice of sand (ENDOH – endohydroarenal). The meanannual phytopsammon biomass was extremely high in all microlayers. Bacterial biomass was the highest in the ENDOH. Biomass of nanoflagellates was 4 to 8 times lower than that of bacteria and was the highest in the AWL. The highest mean annual biomass of ciliates was recorded in the EPIH, whereas rotifers dominated in the ENDOH. In contrast, average biomass of Crustacea was the highest in the AWL. Crustaceans dominated heterotrophic biomass in the AWL and EPIH (92 and 54% of the total biomass, respectively) whereas bacteria definitely prevailed in the ENDOH (57%). The ratios of autotrophic to heterotrophic biomass and prey to predator biomass as well as trophic relations between the studied groups of psammon organisms differed clearly among microlayers. The AWL was characterised by the lowest autotrophic/heterotrophic and predator/prey biomass ratios (about 2) and significant positive correlations between nanoflagellates and ciliates as well as between protists and both rotifers and copepods. The highest autotrophic/heterotrophic and predator/prey biomass ratio (14 and 40, respectively) and lack of correlations was found in the ENDOH. These results may suggest that the pressure of consumers was weaker in the hydroarenal layers than in the AWL. In addition, it seems that psammon ciliates, rotifers and crustaceans inhabiting the ENDOH were probably limited by factors other than food availability. In contrast to the pelagic ecosystems, autotrophic biomass exceeded heterotrophic biomass, especially in the ENDOH.

12

Pursuing parasites up the food chain: Implications of food web structure and function on parasite communities in aquatic systems

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Marcogliese D. J.

Acta Parasitologica

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2001

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tom 46

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nr 2

13

Nematode communities along the transect shelterbelt-ecotone-crop field

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Dmowska E.

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nr 4

EN

The study was carried out in western Poland (Turew region) in two shelterbelts of different age (the younger – 6 years old and the older – 11 years old) planted across croplands, in adjacent fields and in the field located in deforested area (control field). Soil samples were taken twice: in the autumn and spring from the centre of each shelterbelt, from the ecotone, and in the field at a distance of 15 and 50 m from the edge of the shelterbelts. The density of nematode communities fluctuated unpredictably, in autumn it was very low and ranged from 276 to 641×10³, in spring it ranged from 388 to 1931×10³ individuals per 1 m². Most numerous trophic groups were: bacterivores, fungivores and obligate plant feeders, while facultative plant feeders, omnivores and predators achieved low level. The abundance of predators in older shelterbelt was significantly (P ≤0.05) higher than that in the younger one and decreased with increasing distance from the shelterbelt towards the field. The communities in shelterbelt and its ecotone were more diverse, which was reflected by the higher number of genera (19–31) and higher values of Shannon-Wiener diversity index H’(3.3 – 4.0), than those in the fields where the number of genera ranged from 15 to 25 and Shannon-Wiener diversity index H’ ranged from 2.5 to 3.5. In the younger shelterbelt and in the control field the soil food-web assessed with indices derived from analysis of nematode communities was considered as composed mainly of basal components, i.e. cosmopolitan species feeding on bacteria and fungi occurring everywhere even in degraded environments. While the food web in older shelterbelt was consisted mainly of enrichment components, i.e. bacteria feeding species of very short life cycle, with high food requirements which occur in the environment rich in bacteria). The values of Channel Index which informs about the predominant pathway of decomposition (through bacteria or fungi) showed that in majority of sites bacterial processes predominated. Only in the older shelterbelt the participation of fungal decomposition channel was higher (>50%) and increased with increasing distance from the shelterbelt towards the centre of the field. The results of Correspondence Analysis showed that first two axis explained 40.3% of the variance. The generic composition of nematode communities in the 11-years old shelterbelt differed from that in the 6-years old shelterbelt. Nematode communities inhabiting the ecotone of younger shelterbelt were very similar to the communities in the shelterbelt, while the communities in ecotone of older shelterbelt differed from those in the shelterbelts. Nematode communities inhabiting the control field were similar to those inhabiting the field adjacent to younger shelterbelt.

14

Ecological interaction networks: prospects and pitfalls

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Ulrich W.

Ecological Questions

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2009

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tom 11

EN

Interaction networks are a tool to visualize and to study the relationships between interacting species across and within trophic levels. Recent research uncovered many properties of such networks that remained undetected in previous food web studies. These patterns could be related to evolutionary and ecological processes. The study of interaction networks promises therefore progress in the study of constraints that act on the coevolution of interacting species and on food webs. However, there are still many pitfalls associated with the statistical analysis, the properties of the metrics involved and the appropriate null model choice. Here I review the mechanisms that shape interaction matrices, the possible internal structures and their ecological interpretation, and the analytical tools to identify matrix structure. Progress in the field needs critical meta-analytical and comparative studies that indentify the best suited null models (low type I and II error probabilities and high power to disentangle statistical from ecological processes) and clarify the interdependence of different concepts and metrics associated with network approaches. It is not improbable that many patterns recently associated with ecological and evolutionary processes might turn out to be simple side effects of the sampling from the underlying metacommunity distributions.

15

The importance of ciliates as a trophic link in shallow, brackish and eutrophic lakes

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Rychert K. , Wielgat-Rychert M. , Szczurowska D. , Myszka M. , Bochynska M. , Krawiec K.

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tom 60

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nr 4

EN

The importance of ciliates as a trophic link, which is defined as a fraction of the energy bound by primary producers that is transferred through the ciliate community, was assessed in the pelagic zones of shallow, eutrophic, and estuarine lakes. The study was conducted in Lake Gardno and Lake Łebsko located in northern Poland. Each of these lakes is characterized by very high mean annual ciliate biomasses of 115 μg C -1 (Lake Gardno, April 2006 – April 2007), 107 μg C L-1 (Lake Gardno, February 2007 – February 2008), 85 μg C L-1 (Lake Łebsko, April – November 2007), and 127 μg C L-1 (Lake Łebsko, April – September 2008). Ciliate production was estimated using allometric equations and was compared to primary production measured with the light-and-dark bottles method. Annual, depth-integrated ciliate secondary production corresponded to 9 and 11% (Lake Gardno, two consecutive years studied) and 12% (Lake Łebsko, the same value for two growing seasons studied) of primary production. These values exceed the majority of other estimates in the literature, which indicates the high importance of ciliates in such highly-productive, shallow lakes.

16

Fading out of the trophic cascade at the base of the microbial food web caused by changes in the grazing community in mesocosm experiments

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Jasser I. , Kostrzewska-Szlakowska I.

Oceanological and Hydrobiological Studies

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2012

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tom 41

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nr 1

17

Persistent organic pollutants (POPs) in the marine food web: herrings from the Southern Baltic Sea (Clupea harengus) - penguins from the zoo (Spheniscus demersus)

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Reindl A. R. , Bolalek J. , Falkowska L.

Oceanological and Hydrobiological Studies

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2013

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tom 42

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nr 1

18

Autotrophic versus heterotrophic production and components of trophic chain in humic lakes: the role of microbial communities

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Jasser I. , Kostrzewska-Szlakowska I. , Ejsmont-Karabin J. , Kalinowska K. , Weglenska T.

Polish Journal of Ecology

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2009

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tom 57

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nr 3

423-439

EN

The ratio and rates of autotrophic and heterotrophic pathways of organic matter cycles constitute the basic functions of aquatic ecosystem and humic lakes are unique in this respect. The autotrophic and heterotrophic production, the food web structure and the role of microbial communities in three humic lakes (area 1.3–9.2 ha) were studied. The abundance of bacteria, autotrophic picoplankton (APP), nanoflagellates (NF), ciliates, phytoplankton, rotifer and crustacean zooplankton as well as chlorophyll a and primary (¹⁴C method) and bacterial production (³H–thymidine method) were measured. The lakes differed in humic matter content, water colour, pH and hydrology. Two lakes were acidic (pH 5.2–4.9) with different dissolved organic carbon (DOC) content: oligo/mesohumic – 7.1 mg C L⁻¹ , and polyhumic lake – 21 mg C L⁻¹. Due to draining of surrounding meadows, the third lake – formerly humic – experienced changes in the hydrological regime together with liming and fertilisation. Despite low DOC, the oligohumic lake resembled a low productive, typically humic, acidic lake with dominating bacterial production. The lake was characterised by the highest crustaceans biomass and very variable chlorophyll a concentration (between 1.5 and 71 mg Chl a m⁻³). The polyhumic lake had the highest mean and maximal chlorophyll a content but the lowest crustacean biomass, and functioned more like a eutrophic lake. The formerly humic lake had lost probably most of its humic features and experienced a eutrophication process that resulted in a food web structure typical of a shallow eutrophic pond-like environment. The mean chlorophyll a concentration there was at the same level as in an oligohumic lake, but the variability was much lower. This lake can be considered as an example of the posthumic lakes abundant in the managed wetland regions. Microbial communities were numerous in both humic lakes, with bacteria prevailing in microbial biomass in the oligo-humic and APP in the polyhumic lake. In the former humic lake the microbial communities, especially APP, seemed to play a lesser role, while the whole planktonic food web was more balanced. The results demonstrated that uncontrolled drainage and reclamation of wetland can be detrimental to biodiversity of small, mid-forest lakes. Although biodiversity in almost all plankton groups was the highest in the posthumic lake but this lake lacked rare species typical of humic acidic lakes like: Gonyostomum semen, Dictyosphaerium sphagnale from phytoplankton or Holopedium gibberum from crustacean zooplankton. Instead eurytopic species, common in eutrophic waters, were present.

19

Herbivory on macro-algae affects colonization of beach-cast algal wrack by detritivores but not its decomposition

58%

Eereveld P. , Hubner L. , Schaefer G. , Zimmer M.

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nr 2

20

Size-structured interactions and the dynamics of aquatic systems

58%

Persson L. , De Roos A. M.

Polish Journal of Ecology

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2006

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tom 54

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nr 4

EN

Size variation within species as a result of individual growth and development over the life cycle is a ubiquitous feature of many aquatic organisms. We review the implications of this size variation for the dynamics of aquatic systems. Ontogenetic development results in differences in size dependent competitive abilities between differently sized individuals giving rise to cohort cycles that are qualitatively different from traditional predator prey cycles. Size-dependent interactions also mean that the type of interaction – competitive or predatory – changes over the life cycle as a result of an increase in size. At the intraspecific level, cannibalistic interactions may, depending on the life history characteristics of the cannibal, give rise to either equilibrium or cycles driven by a mixture of inter-cohort cannibalism and competition. In multispecies contexts, size variation and particularly food dependent growth lead to the presence of alternative states involving catastrophic collapses. These sizestructured interactions have so far been mainly demonstrated for fish and cladocerans, but do have whole lake food web ramifications.