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1

Złoto : blaski i cienie żółtego kruszcu

Krzak Mariusz

Przegląd Geologiczny

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2024

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Vol. 72, nr 7

332--340

EN

Gold, despite the low production and consumption levels, is the one of the strategically important metals for the world economy. Gold has been treated for hundreds of years as a stable, valuable and safe asset, especially in times of fiat money, when the costs of goods and services are rising and the purchasing power of national currencies is reduced. Massive purchases (stock buildings) of gold are currently being observed, not only by central banks, and gold prices have reached levels unquoted in history. The basic sources and supplies directions of primary gold raw materials have been discussed in the paper. The consumption structure and gold trade were indicated, as well as the risk and market prospects were assessed. The resource base potential of Poland was presented and the national economy of gold raw material was briefly characterized.

2

Seasonal enhancement of phytoplankton biomass in the southern tropical Indian Ocean: Significance of meteorological and oceanography parameters

Karnan Chinnadurai, Gautham Sreedharan

Oceanologia

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2024

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Vol. 66 (2)

196--219

EN

The present study focused on understanding the seasonality of the phytoplankton biomass (chlorophyll a) distribution in the oligotrophic, Equatorial, and Southern Tropical Indian Ocean (ESTIO; 0–30°S and 60–90°E). The long-term satellite data analyses (2003–2020) showed a strong seasonality in sea surface temperature (SST), wind, currents, mean sea level anomaly (MSLA), photosynthetically available radiation (PAR), euphotic depth (ZEU) and mixed layer depth (MLD). As a response to the hydrographical changes, the phytoplankton biomass showed noticeable seasonal variation with the highest biomass during the Austral Winter (AW; June–September; avg. 0.11 ± 0.03 mg/m³) and lowest during the Austral Summer (AS; November–February; avg. 0.07 ± 0.03 mg/m). High chlorophyll patches (>0.1 mg/m³) were found between 0°–8°S during the AS and expanded over 0°–18°S during the AW. As multi-year mean chlorophyll a was higher (>0.1 mg/m³) in the northern part of the ESTIO (north of ∼13°S; HCD: high chlorophyll a domain) than the southern side (LCD: low chlorophyll a domain), the study area was divided into two domains and all the variables were analysed. In the HCD, enhancement of chlorophyll a was positively correlated with variables such as wind speed, wind stress, Ekman pumping, stronger northward and westward winds, as well as the presence of cyclonic eddies. These features are likely to stimulate primary production by uplifting the thermocline and enhancing nutrient supply. In the LCD, mixed layer depth also showed a strong positive correlation with elevated chlorophyll a, apparently because it is deep throughout the year (thereby keeping lower biomass) and deepens more strongly in winter than in the HCD. Another contrast with the HCD is that the cyclonic eddies appear to be insufficiently abundant to influence its chlorophyll a. Pearson's multivariable correlation analysis and principle component analysis confirmed the statistical significance of the above parameters on the enhancement of chlorophyll a in the ESTIO.

3

The influence of biochemical parameters on primary production in the Gulf of Gdańsk region : A model study

Janecki Maciej, Dybowski Dawid, Dzierzbicka-Głowacka Lidia

Oceanologia

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2023

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Vol. 65 (4)

517--533

EN

Understanding the changing levels of biochemical parameters and the factors that influence them throughout the seasons is crucial for comprehending the dynamics of marine ecosystems. It also helps us identify potential threats that could harm their condition, aiding decision-making processes related to their protection. This study focuses on examining the variations in nutrients (such as nitrates, phosphates, and silicates), dissolved oxygen, and phytoplankton within the Gulf of Gdańsk. Additionally, we analyze the primary production process at three representative locations. To achieve this, we used data from the EcoFish biochemical numerical model. To ensure the model's accuracy, we compared its results with in situ data from the ICES database. The comparison revealed high correlations and minimal errors. Furthermore, we investigated how limiting factors impact primary phytoplankton production and demonstrated how the intensity of spring diatom blooms influences the nature of cyanobacterial blooms in the summer.

4

Seasonal variation in size structure and production of autotrophic plankton community in eutrophied, low-light environment: A focus on Mesodinium rubrum

Labucis Atis, Labuce Astra, Jurgensone Iveta, Barda Ieva, Andersone Ingrida, Ikauniece Anda

Oceanologia

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2023

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Vol. 65 (2)

398--409

EN

Temporal variations in the primary production of the size-fractionated autotrophic plankton community were studied in coastal-estuarine waters of the eutrophic Gulf of Riga, Baltic Sea. The community was net-autotrophic during spring and summer and net-heterotrophic during autumn. The results of the present study clearly demonstrate strong covariation between net primary production (NPP) and <56 µm fractionated community biomass, particularly small-sized (16–33 µm) Mesodinium rubrum, implying that the majority of NPP stems from the lower end of the size spectrum. A pronounced size distribution shift was observed within the M. rubrum population. Large-sized (length ≥34 µm) M. rubrum was the most abundant in the first half of the productive season (until week 24), whereas small-sized M. rubrum dominated during the stratified period.

5

Size-fractionated primary production in the south-eastern Black Sea

Agirbas Ertugrul, Bakirci Mustafa

Oceanologia

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2022

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No. 64 (2)

244--266

EN

Size-fractionated primary production (PP) and chlorophyll-a (Chl-a) with phytoplankton abundance and nutrients were investigated in the south-eastern Black Sea from November 2014 to August 2015. A 14C radio-tracing technique was used to estimate phytoplankton primary production. C-14 experiments revealed that total PP ranged from 295 mgC m−2 d−1 to 5931 mgC m−2 d−1 along the study area. Size-fractionated PP varied from 84 to 1848 mgC m−2 d−1, from 96 to 3156 mgC m−2 d−1 and from 56 to 3363 mgC m−2 d−1 for pico-, nano- and microphytoplankton, respectively. Overall, winter (4163 mgC m−2 d−1) and spring (5931 mgC m−2 d−1) were the most productive seasons, which coincided with high phytoplankton abundance. Contributions of microphytoplankton and nanophytoplankton were prominent in spring with maximum PP values. Winter was the second productive season with high contributions of nano- and microphytoplankton PP. Summer and autumn were less productive seasons, which were characterised by a high contribution of pico- and nanophytoplankton PP. Dinoflagellates were represented with the highest species richness (68 species, 53.54%) and diatoms were the second group along the area. Diatoms and other phytoplankton species (mainly Emiliania huxleyi) were the most abundant groups in terms of quantitative contribution. The results show that microphytoplankton along the study area are responsible for the majority of PP. However, the measured high Chl-a against low size-fractionated PP clearly indicates that smaller groups (i.e., pico- and nanophytoplankton) were dominant during these periods. Hence, the quantification of size-fractionated PP rates together with ecological indicators will allow for a more comprehensive assessment of the Black Sea ecosystem.

6

Rynek tantalu na początku XXI wieku

Krzak Mariusz, Gałaś Andrzej, Król Katarzyna

Przegląd Geologiczny

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2021

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Vol. 69, nr 4

234--243

EN

Tantalum, despite the low consumption level, is one of the strategically important metals for the world economy. In terms of the world production volume, it places oneself on a distant position; however, its price was one of the highest at the beginning of the 21st century. Tantalum is a transition metal with a high melting point and high chemical resistance, which determines the spectrum of its applications. It is used mainly in the capacitors production, sputtering and as an additive for superalloys. The 21stcentury is a period of noticeable changes in the structure of quantitative supplies, consumption centres and price fluctuation. There are numerous but small centres of primary production (artisanal mines) in Africa. Sources of tantalum raw-materials (mineral deposits and its reserves), basic factors determining the economic situation on the market, substitution possibilities and the prices evolution are presented and assessed in the paper. Marginal significance of the economy of tantalum raw materials for Poland is mentioned.

7

Spatio-temporal variability of the size-fractionated primary production and chlorophyll in the Levantine Basin (northeastern Mediterranean)

Yucel N.

Oceanologia

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2018

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No. 60 (3)

288--304

EN

Spatial and temporal variations in size-fractionated primary production (PP) and chl a, in relation to ambient physicochemical parameters, were studied in the three distinct ecosystems of northeastern Levantine Basin namely eutrophic Mersin Bay, mesotrophic Rhodes Gyre, and oligotrophic offshore waters. These ecosystems were visited in July and September 2012 and March and May 2013. Total primary production (TPP) rates ranged between 0.22 and 17.8 mg C m−3 h−1 within the euphotic zone, whereas depth-integrated TPP rates were in the range 21.5-348.8 mg C m−2 h−1 (mean: 105.5 ± 88 mg C m−2 h−1), with the lowest rates recorded for offshore waters. Similar spatio-temporal variations were observed in chl a concentrations, ranging from 2.3 to 117.9 mg m−2 (mean: 28.9 ± 24.9 mg m−2) in the study area. The Mersin Bay TPP rates have exceeded almost 8-12 times those measured in the offshore waters and the Rhodes Gyre; however, the chl a concentrations measured in coastal waters (0.343 mg m−3) and the Rhodes Gyre (0.308 mg m−3) were only threefold larger than the offshore values. PP and chl a were dominated by picoplankton in the study area whereas small nanoplankton, being the most active, displayed the highest assimilation ratio in offshore waters (6.8) and the Rhodes Gyre (2.8). In the upper-layer waters depleted of P (0.02-0.03 μM) of the northeastern Mediterranean, a positive correlation was observed between NO3 + NO2 and PP (and thus, chl a), which strongly suggests that reactive P and inorganic nitrogen are co-limiting factors in the production and biomass distribution of the phytoplankton community in both shelf and offshore waters.

8

Primary productivity in the Gulf of Riga (Baltic Sea) in relation to phytoplankton species and nutrient variability

Purina I., Labucis A., Barda I., Jurgensone I., Aigars J.

Oceanologia

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2018

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No. 60 (4)

544--552

EN

The seasonal patterns of primary production, phytoplankton biomass, chlorophyll a, and nutrients were investigated in the central part of the Gulf of Riga (Baltic Sea) during 2011 and 2012. Annual primary productivity in the gulf was in the range of 353.4–376.2 gC m−2. Maximum carbon fixation rates occurred during the phytoplankton spring bloom from April to May when the winter nutrient pool was rapidly exhausted, suggesting the use of regenerated nutrients already in spring. The new production calculated on the draw-down of nitrates amounted to 51.80% of spring net community production. The production rates during summer were considerably lower owing to the availability of only regenerated nutrients and limited nitrogen fixation. Autumn was established as the least productive season. In autumn despite the elevated nutrient concentrations, the increasingly limited light hindered photosynthetic activity. Species governing the nutrient fluxes and the productivity of the Gulf of Riga are the diatom species responsible for new production in spring. The photosynthetic ciliate Mesodinium rubrum ((Lohmann) Hamburger & Buddenbrock 1911) prevailed in all seasons and significantly correlated with elevated productivity, while diazotrophic cyanobacteria Aphanizomenon flosaquae (Ralfs ex Bornet & Flahault 1886) contributed to new production in the summer nutrient regenerating system.

9

The Relationship between Primary Production and Respiration in the Photic Zone of the Great Mazurian Lakes (GMLS), in Relation to Trophic Conditions, Plankton Composition and Other Ecological Factors

Siuda W., Kauppinen E. S., Kaliński T., Chróst R. J., Kiersztyn B.

Polish Journal of Ecology

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2017

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Vol. 65, nr 3

303--323

EN

The relation of primary production to respiration and dependence of both processes on various environmental factors were investigated in the surface waters of lakes of The Great Mazurian Lake System (GMLS) during summer seasons 2009-2011. Primary production and extracellular release was determined by 14C method, respiration (dark oxygen consumption) - by Winkler's method. Collected results allow to conclude that: (i) in all studied lakes primary production was primarily cyanobacterial, although in mesotrophic ones participation of eukaryotic phytoplankton in light CO2 fixation was more pronounced; (ii) in mesotrophic part of GMLS primary production was limited alternately by N and P availability and less dependent on N and P regeneration processes, whereas in southern, eutrophic lakes it was primarily fueled by regeneration of biogenic substances from organic compounds and strongly limited by N resources; (iii) although in photic zone of whole GMLS respiration was dominated by heterotrophic bacteria, in its mesotrophic part also participation of other plankton components in respiration processes was significant and, (iv) that in eutrophic lakes planktonic respiration was more dependent on low molecular weight products liberated enzymatically from organic substrates than on organic compounds released by primary producers. The mean production to respiration ratio, which varied from 2.11 to 2.60 in northern, and from 2.05 to 3.67 in southern lakes suggested that during period of investigations photic zones of lakes of both parts of GMLS were net autotrophic systems.

10

Hourly and daily variability in nitrogen and phosphorus in a lake restored by the hypolimnetic with drawal method

Sieńska J., Dunalska J. A., Szymański D.

Oceanological and Hydrobiological Studies

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2015

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Vol. 44, No. 3

381--392

EN

An excess of nitrogen and phosphorus causes an increase in productivity, leading to degradation of a water reservoir. In order to reduce the eutrophication, protective and restoration methods are used. The objective of the paper was to determine the hourly and daily variability in nitrogen and phosphorus compounds in a lake restored by the hypolimnetic withdrawal method. In the epilimnion, the organic form dominates: 97% of Ptot and 75% of Ntot. Hourly variations in the concentration of the investigated compounds indicate that the highest values occurred at night and in the morning, whereas lower measurements were recorded at noon and in the evening. Such a distribution of the concentrations of nutrients during a day is strongly associated with photosynthesis. Along with depth, the proportion of this form decreased in favor of mineral forms. A high content of mineral phosphorus (70%) and ammonium ions (75%) in the hypolimnion results from their release from bottom sediments under anaerobic conditions. As a result of the generated thermocline, they are blocked and accumulated. At the experimental station, the concentration of mineral compounds was at a lower level than at the reference station since their amount was systematically reduced by the outflow of over-fertilized waters from the hypolimnion.

11

DOC and POC in the water column of the southern Baltic. Part I, Evaluation of factors influencing sources, distribution and concentration dynamics of organic matter

Maciejewska A., Pempkowiak J.

Oceanologia

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2014

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No. 56 (3)

523--548

EN

Organic substances are important components of the marine environment as they determine the properties of seawater and the key biogeochemical processes taking place in it. Organic carbon (OC) is a measure of organic matter. For practical purposes, OC is divided into dissolved organic carbon (DOC) and particulate organic carbon (POC). Both DOC and POC play a major role in the carbon cycle, especially in shelf seas like the Baltic, where their concentrations are substantial. In a three-year study (2009-2011) seawater samples for DOC and POC measurements were collected from stations located in the Gdańsk Deep, the Gotland Deep and the Bornholm Deep. The accuracy and precision of analysis were satisfactory; the recovery was better than 95%, and the relative standard deviation was 4% (n = 5). Concentrations of chlorophyll a, phaeopigment a, salinity, pH and temperature were also measured in the same samples. These parameters were selected as proxies of processes contributing to DOC and POC abundance. The aim of the study was to address questions regarding the vertical, horizontal and seasonal dynamics of both DOC and POC in the Baltic Sea and the factors influencing carbon concentrations. In general, the highest concentrations of both DOC and POC were recorded in the surface water layer (DOC ~4.7 mg dm-3, POC ~0.6 mg dm-3) as a consequence of intensive phytoplankton activity, and in the halocline layer (DOC ~5.1 mg dm-3, POC ~0.4 mg dm-3). The lowest DOC and POC concentrations were measured in the sub-halocline water layer, where the values did not exceed 3.5 mg dm-3 (DOC) and 0.1 mg dm-3 (POC). Seasonally, the highest DOC and POC concentrations were measured during the growing season: surface DOC ~5.0 mg dm-3; sub-halocline DOC ~4.1 mg dm-3 and surface POC ~0.9 mg dm-3, sub-halocline POC ~0.2 mg dm-3. The ANOVA Kruskal-Wallis test results indicate statistically significant differences among the three study sites regarding average concentrations, and concentrations in particular water layers and seasons. It shows that concentrations of DOC and POC differ in sub-basins of the Baltic Sea. The differences were attributed to the varying distances from river mouths to study sites or the different starting times and/or durations of the spring algal blooms. Statistically significant dependences were found between both DOC and POC concentrations and Chl a (phytoplankton biomass), pH (phytoplankton photosynthetic rate), pheo (zooplankton sloppy feeding), salinity (river run-off and North Sea water inflows) and water temperature (season). This was taken as proof that these factors influence DOC and POC in the study areas.

12

Dobre praktyki rolnicze GAP w produkcji roślinnej i zwierzęcej

Dzwolak W.

Przemysł Spożywczy

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2013

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T. 67, nr 9

32--34

PL

Standardy GlobalGAP są zbiorem dobrych praktyk rolniczych o bardzo szerokim zakresie wymagań, który oprócz produkcji i pozyskiwania surowców żywnościowych obejmuje także elementy związane z ochroną środowiska oraz bezpieczeństwem i higieną pracy. W artykule opisano podstawowe obszary GAP związane z uprawą roślin i hodowlą zwierząt, a także przedstawiono przykładowe opracowania Komisji Kodeksu Żywnościowego (CAC) FAO/WHO odnoszące się do zasad GAP. W artykule przedstawiono strukturę aktualnych standardów GlobalGAP oraz zaprezentowano podstawowe dokumenty obejmujące wymagania ogólne oraz listy kontrolne, punkty kontroli i kryteria zgodności. Artykuł zawiera także opis kategoryzacji wymagań oraz podstawy certyfikacji na zgodność ze standardami GlobalGAP.

EN

GlobalGAP standards form a set of good agriculture practices with a very wide range of requirements including not only production of food raw materials but also some areas of protecting of natural environment as well as occupational and health safety. In article some fundamental GAPs elements relating to crops and livestock were presented and some exemplary codes on GAP developed by the Codex Alimentarius Commission (CAC) FAO/WHO were listed. In the paper, a structure of actual GlobalGAP standards was shown and some basic working documents including checklists, control points and compliance criteria were characterized. In the article, the categorization of requirements and fundamentals of GlobalGAP certification was also described.

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Assessment of Restored Water Bodies in a River-Lake System Based on Phosphorus Concentrations

Sobczyńska-Wójcik K., Rafałowska M.

Ecological Chemistry and Engineering. A

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2011

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Vol. 18, nr 11

1441-1456

EN

Three water bodies restored around 30 years ago were studied: Lake Nowe Wloki, Lake Setalskie Duze and Lake Setalskie Male, connected by the Setal Stream into a single river-lake system in the Olsztyn Lakeland, approximately 25 km north of the city of Olsztyn, in the District of Dywity. The objective of this study was to evaluate the functioning of three water bodies in a river-lake system restored around 30 years ago. Particular attention was paid to water quality and the trophic status of the analyzed lakes, assessed based on seasonal changes in phosphorus concentrations. A river-lake system comprising restored water bodies in rural areas reduces the concentrations of biogens migrating from the catchment area, thus minimizing the effects of potential eutrophication in larger rivers and other water bodies to which the system’s watercourses evacuate. As regards lake inflows, a drop in total phosphorus levels was noted after passage through the water body, and high concentrations of total P resulted from the polymictic character of the studied lakes. The inflows to water bodies that form a chain system supply substantial amounts of total P to the lakes, leading to the retention of excessive phosphorus concentrations and speeding up processes which deteriorate water quality and lake functioning. Over a three-year experimental period, the average concentrations of phosphorus, – an element limiting primary production – varied from 0.22 to 0.34 mg Ptotal dm–3 in the water bodies within the studied river-lake system. The absence of water stratification (hypolimnion) contributed to intensive phosphorus recirculation and very high trophy levels in the examined lakes. According to Nurnberg, the total phosphorus concentrations determined in the spring are indicative of their hypetrophy.

PL

Badaniami objęto trzy zbiorniki wodne odtworzone przed około 30 laty: jezioro Nowe Włóki, jezioro Setalskie Duże i jezioro Setalskie Małe, połączone Strugą Setal w jeden system rzeczno-jeziorny, położone na Pojezierzu Olsztyńskim około 25 km na północ od Olsztyna w gminie Dywity. Celem pracy była ocena funkcjonowania odtworzonych przed około 30 laty zbiorników wodnych, należących do systemu rzeczno-jeziornego, ze szczególnym uwzględnienie jakości wody i stanu troficznego jezior na podstawie stężeń fosforu i jego sezonowych zmian. Istnienie systemu rzeczno-jeziornego, dzięki odtworzonym zbiornikom na terenach wiejskich pozwala na redukcję stężeń (kumulacji związków biogennych) migrujących ze zlewni, zmniejszając w ten sposób skutki potencjalnej eutrofizacji większych rzek i innych akwenów, do których cieki systemu uchodzą. W przypadku wód dopływających do jezior zaobserwowano poprawę w zakresie obniżenia stężeń fosforu ogólnego, po ich przepłynięcie przez akweny, a utrzymywanie się dużych koncentracji Pog w wodach badanych jezior należy wiązać także z ich polimiktycznym charakterem. Z dostawy zanieczyszczeń (Pog) do zbiorników układu paciorkowego wynika, iż wody dopływów wnoszą do jezior znaczne jego ilości, powodując ponadnormatywne stężenia Pog w wodzie akwenów i przyspieszając w ten sposób procesy, które pogarszają jej jakość oraz funkcjonowanie jezior. Stwierdzono, że w wodzie odtworzonych zbiorników średnie z trzech lat stężenia fosforu - pierwiastka limitującego produkcję pierwotną, mieściły się w zakresie od 0,22 do 0,34 mg Pog dm-3. Brak stratyfikacji wód (hypolimnionu), wpłynął na intensywną recyrkulację fosforu i bardzo wysoką trofię wód. Według Nurnberga wiosenne koncentracje Pog, wskazują na stan ich skrajnego przeżyźnienia czyli hipertrofii.

14

Factors controlling pelagic production and respiration in a shallow polymictic lake

Wielgat-Rychter M., Rychter K., Ficek D.

Polish Journal of Ecology

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2010

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Vol. 58, nr 2

379-385

EN

Shallow lakes, defined as 'nonstratifying', polymictic water bodies are usually eutrophic and highly productive, and more turbid than deeper lakes due to bottom sediment resuspension. Gross primary production (GPP) and total planktonic community respiration (TCR) were measured in a very shallow (on average 1.2 m deep) and large (area 25 km2), polymictic, eutrophic Lake Gardno (Baltic coastal lake, Northern Poland) with the light-and-dark bottle method. The aim was to compare GPP to TCR ratio in the pelagic zone in a course of a year and identify factors governing these processes. Identified factors governing GPP were light conditions and temperature, with Q[10] = 2.23 in the 2-24.5[degrees]C temperature range, whereas TCR was driven by water temperature (Q[10] = 2.15 in the same temperature range) and by organic matter content in water. TCR was correlated with total suspended matter (effect of bottom sediment resuspension due to wind action in a very shallow lake), however not with chlorophyll content. During two-year measurement period (years 2006 and 2007), annual GPP amounted to 402 and 471 g C m[^-2], and TCR amounted to 192 and 223 g C m[^-2] respectively. Lake Gardno pelagic system seemed to be net autotrophic on annual basis; GPP to TCR ratio = 2.1. Part of the organic matter produced in pelagial is probably deposited in bottom sediments decomposed there. Wind induced resuspension increases matter content in water (measured here as TSM content) and thus contributes to pelagic respiration processes (TCR).

15

The oxygen budget of two closed, dimictic lakes in the vicinity of Bytów (West Pomeranian Lake District, northern Poland)

Witek Z., Jarosiewicz A.

Oceanological and Hydrobiological Studies

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2010

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Vol. 39, No.2

135-145

EN

The aim of this work was to identify key factors governing the oxygen fluxes in two thermally stratified lakes of different morphology. Oxygen and temperature profiles in lakes Jeleń and Mały Borek, as well as phytoplankton primary production in Mały Borek (oxygen-method) were measured in monthly intervals, except for periods of ice cover. Rates of oxygen release due to photosynthesis, consumption in the water column, loss to atmosphere, depletion in the hypolimnion, and restoration during periods of turn-over were roughly estimated. It was discovered that trophic conditions and morphometry may substantially influence not only the intensity, but also the timing, of particular events in the oxygen cycle of the lakes.

16

Spectral effects in bio-optical control on the ocean system

Sathyendranath S., Platt T.

Oceanologia

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2007

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No. 49 (1)

5-39

EN

The influence of phytoplankton on the spectral structure of the submarine irradiance field is reviewed. The implications for the ocean system of the spectral response by phytoplankton to the ambient light field are discussed. For example, it provides the basis for retrieval of phytoplankton biomass by visible spectral radiometry (ocean-colour remote sensing). In the computation of primary production, the results of spectral models differ in a known and systematic manner from those of non-spectral ones. The bias can be corrected without risk of incurring additional random errors. The models in use for phytoplankton growth, whether based on available light or absorbed light, whether expressed in terms of chlorophyll or carbon, are shown all to conform to the same basic formalism with the same parameters. Residual uncertainty lies less with the models than with the parameters required for their implementation. The submarine light field and the spectral characteristics of phytoplankton carry latent information on phytoplankton community structure. Differences in spectral response by different functional types of phytoplankton are small but significant. Optical considerations limit the maximum phytoplankton biomass that can be sustained in a given surface mixed layer. Moreover, the upper bound on the biomass depends on the spectral response of the dominant phytoplankton taxa. As a result, an optical control exists in the mixed layer that tends to resist extreme excursions of the biomass and also to maintain biodiversity in the phytoplankton.

17

Impact of silicates and detergents on primary production and total biomass of algae in a short-term laboratory experiment

Ciesielczuk T., Czerniawska-Kusza I.

Archiwum Ochrony Środowiska

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2006

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Vol. 32, no. 3

41-54

EN

Silicon, an important clement for diatoms, is often beyond the main object of freshwater researches. In the last decade, many detergents containing silicon compounds have been released by municipal sewage to surface water ecosystems. In this paper, an influence of silicates and washing agents which contain silicates on algal primary production and biomass growth has been shown. The experimental analysis revealed that detergents with the silicate addition increased the rate of the biomass growth and had a direct impact on algal primary production.

PL

Krzem, jeden z ważniejszych pierwiastków dla okrzemek, jest często poza głównym nurtem zainteresowań w czasie badań wód powierzchniowych. W ostatnim dziesięcioleciu wiele związków krzemu z detergentów trafiło do wód powierzchniowych wraz ze ściekami komunalnymi. W niniejszej pracy opisano wpływ krzemianów oraz detergentów krzemianowych na wielkość produkcji pierwotnej oraz ilość wytworzonej biomasy. Testy wykazały, że detergenty zawierające krzemiany zwiększały produkcję biomasy oraz miały wpływ na produkcję pierwotną.

18

The influence of the Hel upwelling (Baltic Sea) on nutrient concentrations and primary production - the results of an ecohydrodynamic model

Kowalewski M.

Oceanologia

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2005

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No. 47 (4)

567-590

EN

An ecohydrodynamic model was used to investigate the effect of the Hel upwelling on nutrient concentrations, primary production and phytoplankton biomass. The model covered the whole Baltic Sea with a 5 NM grid spacing and the Gulf of Gdańsk with a 1 NM grid spacing. Validation indicated good agreement between model results and measurements in the Gdańsk Deep, and slightly weaker concord for the Hel upwelling area. The vertical nutrient fluxes associated with up- and downwelling in the Hel region were simulated for two 30-day periods in 2000. The nutrient input resulting from long-term upwelling is comparable to the load carried into the Gulf of Gdańsk by the Vistula (Wisła), the largest river in the vicinity. Performed at times when upwelling was almost permanent, the simulations showed elevated nutrient concentrations in surface waters. This was especially distinct in spring when primary production and phytoplankton biomass were both higher. In late summer, however, upwelling caused primary production to decrease, despite the elevated nutrient levels.

19

Whole lake primary production assessment by bio-optical modelling

Langner U., Jakob T., Toepel J., Wilhelm C.

Studia Quaternaria

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2004

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Vol. 21

45-49

EN

A hypertrophic lake in Leipzig has been analyzed with respect to the basic limnological parameters, nutrients and phytoplankton community dynamic in the course of the year 2002. A bio-optical model was developed to assess the daily primary production based on the spectrally resolved surface irradiance, the light climate in the euphotic zone of the water column, the quantification of the light absorption by the phytoplankton and its photosynthetic efficiency measured with the help of in-vivo Chla-fluorescence. Summing up the modeled primary production per day for the whole vegetation period it turned out that the productivity was no limited by the nutrients but by the light only. This is the first report that an adopted bio-optical modeling can be used to assess the annual primary production of a whole freshwater lake bio-optical modeling, fluorescence, lake remediation measure, phytoplankton, primary production

20

Practical applications of the multi-component marine photosynthesis model (MCM)

Ficek D., Majchrowski R., Ostrowska M., Kaczmarek S., Woźniak B., Dera J.

Oceanologia

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2003

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No. 45 (3)

395-423

EN

This paper describes the applications and accuracy analyses of our multi-component model of marine photosynthesis, given in detail in Woźniak et al. (2003). We now describe an application of the model to determine quantities characterising the photosynthesis of marine algae, especially the quantum yield of photosynthesis and photosynthetic primary production. These calculations have permitted the analysis of the variability of these photosynthesis characteristics in a diversity of seas, at different seasons, and at different depths. Because of its structure, the model can be used as the "marine part" of break a "satellite" algorithm for monitoring primary production in the sea (the set of input data necessary for the calculations can be determined with remote sensing methods). With this in mind, in the present work, we have tested and verified the model using empirical data. The verification yielded satisfactory results: for example, the statistical errors in estimates of primary production in the water column for Case 1 Waters do not exceed 45%. Hence, this model is far more accurate than earlier, less complex models hitherto applied in satellite algorithms.