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1

Role of psammon microinvertebrates in phosphorus cycling in hydroarenal of an eutrophic lake

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Ejsmont-Karabin J., Gorelysheva Z., Kalinowska K., Rybak J. I.
Polish Journal of Ecology
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2012
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tom 60
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nr 3
Inorganic phosphorus released from littoral bottom sediments plays significant role in phosphorus budget of a whole ecosystem. An aim of the study was to assess a role of small invertebrates in phosphorus remineralization in hydroarenal (See Fig.1 in Preface). Hydropsammon organisms (i.e. bacteria, algae, ciliates, rotifers and crustaceans) living in a layer of submerged sands along the edge of a lake (=hydroarenal) were studied in psammolittoral of the deep, eutrophic Lake Mikołajskie (North-eastern Poland) in 2005. Sampling cores were taken at a station 1.5 m from water’s edge once or twice a month since April until October 2005. Each time three samples were taken: 5-cm thick water layer (AWL – adjacent water layer), 0.5-cm thick layer of water and sand from the transitory level (EPIH – epihydroarenal) and 2-cm thick slice of sand (ENDOH – endohydroarenal). The rate of phosphorus excretion was calculated using the appropriate regression equations expressing the relation between individual weight of organism and P excretion adjusted to the ambient temperature. Phosphorus remineralization by the psammon community (calculated for all ciliates, rotifers and crustaceans) was ca. 10 times higher than the maximum rate noted in lake pelagial. The most important role in the process was played by small ciliates, and in periods of high remineralization rate – by small cladocerans. Omnivores, feeding mostly on bacteria and small algae, played the most important role in all three studied layers, especially in periods of the highest rate of P remineralization, thus all kinds of food were used and mineralized. Predators do not seem to play significant role in P remineralization. In hydroarenal significant role seems to be played by processes involved in microbial loop. This suggestion is supported by strong domination of ciliates, main consumers of nanoflagellates, in the process of P remineralization. It seems that phytopsammon and psammic bacteria demands for phosphorus cannot be satisfied merely through the in situ remineralization by microinvertebrates.
2

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.
Polish Journal of Ecology
|
2012
|
tom 60
|
nr 3
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.
3

Zoelucasa sablensis n. gen. et n. sp. (Cercozoa, Incertae sedis), a new scale-covered flagellate from marine sandy shores

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Nicholls K. H.
Acta Protozoologica
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2012
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tom 51
|
nr 2
4

The structure of psammic rotifer communities in two boreal lakes with different trophic conditions: Lake Vortsjarv and Lake Saadjarv (Estonia)

100%
Lokko K., Virro T.
Oceanological and Hydrobiological Studies
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2014
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tom 43
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nr 1
5

Interstitial testate amoebae [Rhizopoda: Testacea] from the Italian Coast of the Mediterranean Sea

100%
Golemansky V.
Acta Protozoologica
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1998
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tom 37
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nr 3
6

Rotifera of lake psammon: community structure Versus trophic state of lake waters

100%
Ejsmont-Karabin J.
Polish Journal of Ecology
|
2003
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tom 51
|
nr 1
Rotifer communities inhabiting wet sands of lake beaches are dependent in their functioning on permanent input of organic matter from neighbouring sites. The aim of the study is to test the hypothesis that trophic state of lake waters may influence densities and structure of psammon communities of Rotifera. Studies were carried out in hydro-, hygro- and euarenal of 44 beaches in 18 lakes of different trophy in summer 1999 (since 2 till 17 July) and 38 beaches in 16 lakes in spring 2000 (since 10 till 23 May). Psammon was sampled always between 10 a.m. and 2 p.m. at similar weather conditions (no shadow, rains and strong winds). Interstitial waters were mostly alkaline and contained less oxygen than lake ones and oxygen concentrations decreased upward water line. Very high variability of phosphate P content made differences between trophic groups of lakes not significant. Similarly, concentrations of P total were more or less similar in all studied trophic groups of lakes. Total nitrogen values were increasing from meso-eutrophic to hypertrophic lakes in spring, whereas this trend was not observed in summer. Chlorophyll a concentrations were similar in meso-, meso-eu- and eutrophic and markedly higher in hypertrophic lakes. In general, some tendency to increasing values of chemical parameters with increasing trophy may be seen if their ranking list is compared. Rotifers were present in all studied stations. In total, 110 species (i.e. ca. 26% of all records of rotifer species in Poland) were found with 22 species occurring exclusively in psammon. Three species new in rotifer fauna of Poland were discovered Cephalodella psammophila, Collotheca wiszniewski and Euchlanis dapidula. Generally all trophic groups of lakes were relatively similar as regards species structure of rotifer communities with rotifers of the genus Lecane playing most important role. The index of Percentage Similarity of Community calculated tbr randomly chosen 30 pairs of particular beaches from the same lake and for beaches of different lakes was in both cases almost identical. Species of high frequency constituted the overwhelming majority of individuals forming rotifer communities of all beaches. Taxons met in 1 to 5 lakes decided on faunistic originality of the communities. Some tendency was observed for higher diversity of psammon rotifer communities in mesotrophic and eutrophic lakes. The lowest values of diversity index occurred mostly in hypertrophic lakes. Psammobionts constituted only 20% and psammoxens 10% of the community abundance in all lakes and all zones of the beaches, whereas psammophilic rotifers decidedly dominated (70%). Rotifer abundance was relatively similar in eu- and hypertrophic lakes and markedly higher in mesotrophic and lower in meso-eutrophic lakes. However, due to high fluctuations of the values noted in particular beaches the differences were not significant in any of the possible configurations of compared data. Monogononta played much more important role in rotifer densities than bdelloids. The hypothesis on advantageous influence of high trophy of lake waters on abundance of psammon communities of Rotifera cannot be supported by results of this work. In lakes of moderate trophy (from meso- to eutrophy) the amount of nutrients and chlorophyll does not seem to influence psammon communities. In hypertrophic lakes this impact is observed, but it seems to be rather unfavourable for psammon rotifers. The communities in hypertrophic lakes are poorer in species, less diversified and less original. The group of animals developing well in this group of lakes are bdelloids. Species composition nad community structure of psammon rotifers seem to be rather determined by many different factors, lake trophy being only one of them and probably not the main one.
7

Interstitial testate amoebae [Rhizopoda: Arcellinida and Gromida] from the finnish coast of the Baltic Sea and summary check list of the interstitial testate amoebae in the Baltic Sea

100%
Golemansky V.
Acta Protozoologica
|
1998
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tom 37
|
nr 3
8

Diversity and abundance of Gastrotricha in the psammon of mesotrophic lake

100%
Nesteruk T.
Polish Journal of Ecology
|
2007
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tom 55
|
nr 4
Composition and abundance of Gastrotricha in lake psammon were studied and compared with those from other lake habitats. Samples were taken from April till October 2004 from 3 sites at the edge of zone frequently wetted by waves (hygropsammon) in a deep (38 m) mesotrophic lake situated in Łęczyńsko-Włodawskie Lakeland (south-eastern Poland). A total of 11 gastrotrich species belonging to Chaetonotidae family were found. Three species: Lepidodermella squamata Dujardin, Chaetonotus macrochaetus Zelnika i Ch. heideri Brehm dominated (52%) in total abundance. According to the previous studies the number of species occurring in bottom sediments of the same lake was higher by 11–14 species. Species diversity index H’, amounted 2.19 being lower than that calculated for the gastrotrichs of inshore bottom and littoral sediments (2.88 and 2.58, respectively) and similar to the value given for epiphytic fauna (2.01) of that lake. The fauna of psammic Gastrotricha showed the greatest similarity (38%) to epiphytic fauna of that lake as measured by the index of homogeneity. Peak densities of psammic Gastrotricha were found in May (37.5 10³ ind. m⁻²) and in September (32.8 10³ ind. m⁻²) and marked decrease of density was observed in August and October (18.1 10³ ind. m⁻² and 13.6 10³ ind. m⁻², respectively). Mean density and biomass were 25.35 10³ ind. m⁻² and 3.8 mg m⁻² respectively. Density and biomass of Gastrotricha were by two orders of magnitude lower in psammon than in bottom sediments of the lake.
9

Are community composition and abundance of psammon Rotifera related to grain-size structure of beach sand in lakes?

100%
Ejsmont-Karabin J.
Polish Journal of Ecology
|
2004
|
tom 52
|
nr 3
The aim of the study was to test the hypothesis that the size distribution of sand grains in lake beach should affect the species composition, densities and body-size structure of psammon communities of Rotifera. Studies were carried out in hydro-, hygro- and euarenal zones of 38 beaches (5 to 50 m long and 1 to 10 m wide) in 16 lakes of different trophic status and morphometry (Masurian Lakeland, Poland). Porosity has no impact on psammon rotifer numbers as well as body-size of animals does not seem to play a significant role in species preference to different size classes of sand grains. However, the significant correlations were found between the rotifer numbers and the share of grain size fraction 0.25–1.00 mm (positive) and the share of the largest (i.e. >1 mm) fraction (negative). The psammobionts generally are more related to the grain size fraction 0.5–1.0 mm than the psammoxenes and psammophiles. Although particular rotifer species prefer different grain size fractions, bdelloids are the only group of Rotifera preferring the smallest (<0.125 mm) grain fraction.
10

Psammon algae: composition and spatial distribution in hygroarenal of eutrophic lake

80%
Kalinowska K., Gorelysheva Z., Ejsmont-Karabin J.
Polish Journal of Ecology
|
2011
|
tom 59
|
nr 1
Psammon habitats like freshwater sandy shores are the peculiar sites due to high fluctuation of physico-chemical conditions and due to the specific composition of the organisms communities distributed along the horizontal pattern related to the wave action. Taxonomic composition, numbers and biomass of phytopsammon were studied in hygroarenal (shore sand beach wetted by lake waves) of the small beach of the eutrophic Lake Mikołajskie (area 498 ha, max. depth 26 m) (Masurian Lake District, Poland). Samples were collected on one occasion (26 June 2003) from 30 sampling stations distributed parallel to lake shore along 10 m line at three different distances (sampling points A, B, C) from 0 to 60 cm from water line. The studies showed distinct horizontal distribution of psammon algae. Their numbers and biomass varied from 2.22 to 31.85 × 03 cm–3 of sand and from 0.49 to 4.69 μg cm–3 of sand, respectively. Mean numbers in all sampling distances were very similar, while the biomass increased with increasing distance from water line. Cyanoprokaryota, among which Oscillatoria spp. were most numerous species, dominated in the numbers, whereas Bacillariophycea (mainly Stephanodiscus hantzschii Grun. and Fragillaria spp.) constituted significant proportion of the total algae biomass. There were no significant correlations between abundance of algae and size fractions of sand. Among taxonomic groups, only the biomass of Cyanoprokaryota showed positive correlations with trophic parameters (TP, TN). The studies did not show any correlations between phytopsammon and the abundances of ciliates and rotifers, suggesting that different environmental factors as well as organisms of the higher trophic levels may play a decisive role in the development and horizontal distribution of algae in hygroarenal of the beach of the eutrophic lake.
11

Community structure of psammon ciliates in sandy beaches of lakes

80%
Kalinowska K.
Oceanological and Hydrobiological Studies
|
2013
|
tom 42
|
nr 1
12

The role of lake shore sand deposits as bank of ciliate, rotifer and crustacean resting forms: experimental approach

80%
Kalinowska K., Ejsmont-Karabin J., Rybak J. I.
Polish Journal of Ecology
|
2010
|
tom 58
|
nr 2
The experiment, with the use of sand deposit from hygroarenal (shore sand beach wetted by lake waves) of the beach of eutrophic Lake Mikołajskie (Masurian Lakeland, Poland), was performed in order to test the hypothesis that shore sand deposit is the bank of resting forms of ciliate, rotifer and crustacean species. The experiment was conducted over a 38 days period in March-April 2004. Frozen sand taken in winter was exposed in aquariums filled with pre-filtered (GF/C) lake water in stable temperature (20ºC), oxygen saturation and 12:12 light/dark conditions. Samples (three replicates) were taken each day. A total number of 44 ciliate, 59 rotifer and 9 crustacean taxa were identified during the studied period. Resting forms of different species and/ or taxonomic groups developed in different time and it may be the result of different strategies in colonization of new habitats. Organisms forming resting cysts such as ciliates (11 species) and bdelloid rotifers appeared after the first day of the incubation whereas organisms hatching from resting eggs (monogonont rotifers and crustacea) were observed from the 2nd-3rd day of the experiment. The numbers of all the studied groups of organisms increased gradually and then strongly decreased indicating probably nutrient and/or organic matter limitation. The highest numbers of ciliates (731 ind. cm⁻² of sand) was found on the 5th day, rotifers (987 ind. 100 cm⁻²) on the 23rd day, cladocerans (60 ind. 100 cm⁻²) on the 21st day and copepods (30 ind. 100 cm⁻²) on the 33rd day of the experiment. The results of this study suggests that shore sand deposits being the temporal refugium for the small-bodied invertebrates transported here with the wave action may also play an important role as the transfer for their further dispersal in addition to postulated ways of expansions such as wind, rain, animals and surface runoff.
13

Vertical micro-distribution of psammonic ciliates and their relationship to physical and chemical parameters in two lakes of different trophic status

80%
Mieczan T., Nawrot D.
Oceanological and Hydrobiological Studies
|
2012
|
tom 41
|
nr 2
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