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1
Content available remote Can seabirds modify carbon burial in fjords?
Węsławski J. M., Urbański J., Głuchowska M., Grzelak K., Kotwicki L., Kwaśniewski S., Legeżyńska J., Wiktor J., Włodarska-Kowalczuk M., Zaborska A., Zajączkowski M., Stempniewicz L.
Oceanologia
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2017
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No. 59 (4)
603--611
EN
Two high latitude fjords of Spitsbergen (Hornsund 77°N and Kongsfjorden 79°N) are regarded as being highly productive (70 g and 50 gC m−2 year−1) and having organic-rich sediments. Hornsund has more organic matter in its sediments (8%), nearly half of it of terrestrial origin, while most of that in Kongsfjorden (5%) comes from fresh, marine sources (microplankton). Analysis of the carbon sources in both fjords shows that a major difference is the much larger seabird population in Hornsund-dominated with over 100 thousands pairs of plankton feeding little auks in Hornsund versus 2 thousand pairs in Kongsfjorden, and marine food consumption estimated as 5573 tonnes of carbon in Hornsund, versus 3047 tonnes in Kongsfjorden during one month of chick feeding period. Seabird colonies supply rich ornithogenic tundra (595 tonnes of C, as against only 266 tonnes of C in the Kongsfjorden tundra). No much of the terrestrial carbon, flushed out or wind-blown to the fjord, is consumed on the seabed – a state of affairs that is reflected by the low metabolic activity of bacteria and benthos and the lower benthic biomass in Hornsund than in Kongsfjorden.
2
Content available remote Colonies of Gyrosigma eximium: a new phenomenon in Arctic tidal flats
Wiktor J., Tatarek A., Węsławski J. M., Kotwicki L., Poulin M.
Oceanologia
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2016
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No. 58 (4)
336--340
EN
For the first time at Svalbard, a colonial form of the tube-dwelling diatom Gyrosigma eximium was found in summer 2010 in the tidal flats on Spitsbergen at 78°N. The colonies take the form of conical, green structures that are 1–2 cm high and are associated with other diatom taxa and cyanobacteria (Oscillatoriaceae). The diatom colonies were associated with rich meiofauna and apparently act as cohesive factors for the fine sediment. In the Arctic tidal flats, this represents the first observation of long-term sediment stabilization and biological enrichment. Since this first observation, this species has apparently colonized broader areas in Advenentelva's tidal flat.
3
Content available remote Large red cyanobacterial mats (Spirulina subsalsa Oersted ex Gomont) in the shallow sublittoral of the southern Baltic
Włodarska-Kowalczuk M., Balazy P., Kobos J., Wiktor J., Zajączkowski M., Moskal W.
Oceanologia
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2014
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No. 56 (3)
661--666
EN
We report the first observation of large red cyanobacterial mats in the southern Baltic Sea. The mats (up to 2.5 m in diameter) were observed by SCUBA divers at 7.7 m depth on loamy sediments in the Gulf of Gdańsk in mid-November 2013. The main structure of the mat was formed by cyanobacteria Spirulina subsalsa Oersted ex Gomont; a number of other cyanobacteria, diatoms and nematode species were also present. After a few days in the laboratory, the red trichomes of S. subsalsa started to turn blue-green in colour, suggesting the strong chromatic acclimation abilities of this species.
4
Content available remote Genetic characteristics of three Baltic Zostera marina populations
Gonciarz M., Wiktor J., Tatarek A., Węgleński P., Stanković A.
Oceanologia
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2014
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No. 56 (3)
549--564
EN
We performed genetic analyses of three Baltic eelgrass (Zostera marina) populations in Puck Bay (PB), Cudema Bay (CB) and Greifswalder Bodden (GB). The aim of this study was to identify the eelgrass population genetically closest to that from the PB, which could potentially serve as a reservoir for the restoration of the underwater meadows in this bay, seriously degraded in the past. We applied a 12-microsatellite assay to test the genetic distance between the target eelgrass populations. We found that the allelic richness values of the GB, PB and CB populations were 2.25, 3.77 and 3.50 respectively. The genetic diversity found in GB was low and could be explained by the population's history, whereas the diversity of CB was higher than expected in a population located at the edge of the species' range. Analyses of genetic differentiation and structure showed that of the three populations studied, PB and CB were closer to each other than to the GB population. The reasons for this differentiation in eelgrass populations and the implications of the results of their genetic analysis on the planned restoration of the PB populations are discussed.
5
Content available remote Habitat modelling limitations - Puck Bay, Baltic Sea - a case study
Węsławski J.M., Kryla-Straszewska L., Piwowarczyk J., Piwowarczyk J., Urbański J., Warzocha J., Kotwicki L., Włodarska-Kowalczuk M., Wiktor J.
Oceanologia
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2013
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No. 55 (1)
167-183
EN
The Natura 2000 sites and the Coastal Landscape Park in a shallow marine bay in the southern Baltic have been studied in detail for the distribution of benthic macroorganisms, species assemblages and seabed habitats. The relatively small Inner Puck Bay (104.8 km2) is one of the most thoroughly investigated marine areas in the Baltic: research has been carried out there continuously for over 50 years. Six physical parameters regarded as critically important for the marine benthos (depth, minimal temperature, maximum salinity, light, wave intensity and sediment type) were summarized on a GIS map showing unified patches of seabed and the near-bottom water conditions. The occurrence of uniform seabed forms is weakly correlated with the distributions of individual species or multi-species assemblages. This is partly explained by the characteristics of the local macrofauna, which is dominated by highly tolerant, eurytopic species with opportunistic strategies. The history and timing of the assemblage formation also explains this weak correlation. The distribution of assemblages formed by long-living, structural species (Zostera marina and other higher plants) shows the history of recovery following earlier disturbances. In the study area, these communities are still in the stage of recovery and recolonization, and their present distribution does not as yet match the distribution of the physical environmental conditions favourable to them. Our results show up the limitations of distribution modelling in coastal waters, where the history of anthropogenic disturbances can distort the picture of the present-day environmental control of biota distributions.
6
Content available remote Biological valorisation of the southern Baltic Sea (Polish Exclusive Economic Zone)
Węsławski J.M., Warzocha J., Wiktor J., Urbański J., Bradtke K., Kryla L., Tatarek A., Kotwicki L., Piwowarczyk J.
Oceanologia
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2009
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No. 51 (3)
415-435
EN
A biological valuation system to assess the value associated with ecosystem stability and richness (and not that from the point of view of users) is proposed to provide scientific decision support for marine protected areas and marine spatial planning. The system is based on the assessment of individual species and habitat/species assemblages. An extensive set of recently collected (2007-08) and archival (1970-2000) data on the occurrence of marine benthos was analysed for the Polish Marine Areas. Based on matching data sets of sediments, the euphotic zone, temperature and salinity, as well as fetch and sea current values, a GIS model was used to visualise the results; a map indicates the two areas which are considered to be biologically the most valuable (Puck Bay and the stony shallows of the central coast).
7
Content available Acoustic estimation of macrophytes in the Hornsund Fjord (The Svalbard Archipelago)
Kruss A., Tęgowski J., Wiktor J., Tatarek A.
Hydroacoustics
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2006
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Vol. 9
89-96
EN
In this paper we examine the use of side scan sonar for estimation and spatial distribution of macrophytes in Arctic conditions. Acoustic observation were verified by video recordings and biological samplings. Single beam echosounder was also used. The Hornsund Fjord represents a periglacial environment with great diversity of morphodynamic processes and sensitivity for global warming changes so it is one of the most promising areas to research the influence of the climate’s impact on ecosystem. Side scan sonar is a very effective and economic tool for mapping marine vegetation on the seafloor but interpretation of data still causes many problems especially in the specific conditions of the Arctic fjords (underwater rocks, postglacial sediments, steep slopes). We have created segmentation and classification algorithm based on the two-dimensional discrete wavelet decomposition of echo signals and fuzzy c-means data clustering. The algorithm was verified using biological data.
8
Uzębienia walcowe obrabiane narzędziami kołowymi o uzębieniu wewnętrzym
Wiktor J.
Przegląd Mechaniczny
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2005
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nr 6
26-31
9
Geometria ostrza dłutaka modułowego w układzie roboczym
Wiktor J.
Przegląd Mechaniczny
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2004
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nr 4
18-24
PL
W artykule przedstawiono analityczną metodę wyznaczania wartości kątów natarcia i przyłożenia, pozwalającą określić geometrię ostrza w rzeczywistych warunkach skrawania i to dla bardzo złożonej kinematycznie metody obróbki, jaką jest dłutowanie uzębień metodą Fellowsa. Zaproponowana metoda opiera się na matematycznym opisie powierzchni roboczych ostrza i została zastosowana z powodzeniem jako nowa metoda do badań geometrii ostrza w rzeczywistych warunkach skrawania. Metoda została zweryfikowana praktycznymi obliczeniami ilustrującymi zmienność kątów roboczych dłutaka, potwierdzającymi obserwowane zjawiska zużycia w praktyce.
EN
The paper presents analytical method of estimation tool rake and tool clearance angles value enabling cutting edge geometry evaluation during machining. This method can be used for teethes slotting according to the Fellows method. Presented method based on mathematical description of the active face of cutting edge and was applied as a new method of tool geometry investigation during machining. This method was verified by calculations that exhibit variability of angles of pinion type cutter.
10
Content available remote Microphytobenthic primary production along a non-tidal sandy beach gradient : an annual study from the Baltic Sea
Urban-Malinga B., Wiktor J.
Oceanologia
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2003
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No. 45 (4)
705-720
EN
The microphytobenthic primary production and chlorophyll a content were studied over the annual cycle (May 1998 - May 1999) on a non-tidal Baltic sandy beach at three stations along the beach gradient: littoral, waterline and splash zone. The chlorophyll a concentrations varied between 0.88 and 12.18 žg cm-3. Net and gross primary production rates respectively lay within the ranges 0.1-31.4 mgC m-2 h-1 and 0.2-41.8 mgC m-2 h-1. The highest values of both Chl a content and primary production were noted at the littoral station, the lowest ones at the waterline. The mean annual P/B ratio was highest at the waterline. The differences in Chl a content between stations were statistically significant and may be related to water dynamics, resuspension and water content. Production rates were highly variable on monthly time scales, and the highest results at all the study locations were noted in July. The gross photosynthetic rates were significantly correlated with water temperature.
11
Content available remote Analiza śladu styku (TCA) w przekładni wichrowatej koło-zębatka
Rejman E., Wiktor J.
Archiwum Technologii Maszyn i Automatyzacji
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2002
|
Vol. 22, Nr 2
135-144
PL
W artykule przedstawiono analityczną metodę wyznaczania śladu styku zębów w przekładni wichrowatej koło zębate-zębatka. Omówiono metodykę wyznaczania linii styku i wykazano, że styk między zębami jest liniowy. Rozważania teoretyczne potwierdzono przykładami numerycznymi i badaniami eksperymentalnymi, którym poddano model wykonany metodą stereolito-grafii.
EN
In the paper the method of determining tooth contact trace in rack — and - pinion transmissions has been presented. The method of tracing contact line has been discussed. Authors have shown that the contact between teeth is linear. Theoretical assumptions have been proved by numerical examples and by research conducted on the model formed by using method of stereolitography.
12
Analytical and numerical method of determination of cylindical gear tooth profile machined by gear tools.
Kawalec A., Wiktor J.
Postępy Technologii Maszyn i Urządzeń
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1999
|
Vol. 23, nr 2
5-28
EN
The paper presents analytical and numerical method of determination of spur gear tooth form machined by gear tool during generation. Tooth form is calculated as en envelope of a family of curves made by cutting edge outline in its rolling movement relative to the machined gear. Mathematical formulas for calculation of the parameters of critical section (in accordance with the DIN 3990 and ISO/DIS 6336 standards) at tooth root, in which maximal stresses occur, are given. These formulas, have been applied in design of gear transmissions and in design of generating tools used for machining of complex spur gearings (helix internal gearings, gearings with undercutting at tooth root, gearings with tooth profile modification) including also very responsible aviation gear transmissions. They have been also implemented in finite element modelling of spur gearing, in order to calculate the distribution of strains and stresses in gear tooth.
PL
W pracy przedstawiono analityczną metodę wyznaczania zarysu uzębienia walcowego, odwzorowanego w wyniku obróbki obwiedniowej narzędziem kołowym. Zarys zęba wyznaczono jako obwiednię rodziny krzywych utworzonej przez zarys ostrza narzędzia w jego ruchu tocznym względem koła obrabianego. W pracy podano zależności pozwalające na obliczenie parametrów przekroju obliczeniowego (wg zaleceń norm DIN 3990 i ISO/DIS 6336), tj. przekroju u podstawy zęba, w którym występują największe naprężenia. Wykorzystano je również do modelowania uzębień walcowych metodą elementów skończonych, w celu obliczenia rozkładu odkształceń i naprężeń w zębie. Zostały one zastosowane do projektowania przekładni zębatych oraz w projektowaniu narzędzi obwiedniowych do obróbki bardzo złożonych uzębień wlacowych (uzębień wewnętrznych śrubowych, uzębień z podcięciem u podstawy, uzębień z modyfikacją zarysu) - w tym także bardzo dokładnych i odpowiedzialnych przekładni lotniczych.
13
Content available remote Early spring microplankton development under fast ice covered fjords of Svalbard, Arctic
Wiktor J.
Oceanologia
|
1999
|
No. 41 (1)
51-72
EN
The chlorophyll a concentration, phytoplankton taxa succession, density, biomass and sedimentation was studied in three fjords of Svalbard in January, April and May 1995 and 1996. The fjords were covered with variable fast ice cover ranging in thickness from 0.4 to 1.5 m. Samples collected from the water column showed that only 10% of the algae could be classified as ice algae species. The fjord phytoplankton grew well under very poor light conditions (< 1% of incident radiation). The phytoplankton biomass ranged from 1.7 gC m-2 in winter to 15 gC m-2 in May. Heterotrophic flagellates made a significant contribution to the biomass (up to 98%), especially at stations with poor light conditions (inner fjord basins and thick ice cover).
14
Wpływ odmiany i parametrów modyfikacji powierzchni bocznej zęba na pole styku zębów w przekładni walcowej
Wiktor J.
Przegląd Mechaniczny
|
1998
|
nr 15
15-20
PL
W artykule przedstawiono analityczną metodę wyznaczania pola styku w przekładni z modyfikacją powierzchni bocznej zębów; metoda ta oparta jest na komputerowej symulacji współpracy zębów - można ją zastosować już na etapie projektowania przekładni i może być pomocna przy doborze odmiany i parametrów modyfikacji.
EN
The article presents an analytical method od detremining the contact area in a transmission with modification of the contact flank of teeth. This method is based on a computer simulation of teeth intermating. It can be applied as early as in the stage of designing a transmission and can be of use in chossing the from and parameters of modification.
15
Content available remote Phytoplankton and water masses in the European subarctic Polar Front zone
Markowski D., Wiktor J.
Oceanologia
|
1998
|
No. 40 (1)
51-64
EN
Phytoplankton and hydrological data were collected during the Greenland Sea Project between 74o and 76oN, 13o and 20oE, in July 1988 and 1991. The water masses were very different with regard to their hydrology in the two years, especially with regard to the displacement of the frontal zone. The phytoplankton community was similar in both years, however. Multivariate analyses have not shown any significant relationship between phytoplankton abundance, salinity, nutrients and temperature. It was assumed that the water mass as a single, comprehensive system influences phytoplankton occurrence, and its origin determines the phytoplankton recorded in the frontal zone.
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