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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.

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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.

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Relationship between groundwater depth and pattern of net primary production in oasis-desert ecotone

Wu F., Deng J., Li T., Wang G., Wei X., Zhao C.

Polish Journal of Ecology

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2010

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Vol. 58, nr 4

681-692

EN

Pattern of plant biomass and net primary production was investigated in two localities (Minqin and Linze) of oasis-desert ecotone (ODE) in Northwest China, in order to recognize the spatial and temporal variability of vegetation under same regional climate with different groundwater depth. The average depth to groundwater was over 14.02 m at Minqin - marked further as DG (deep groundwater) and about 4.96 m at Linze - marked further as SG (shallow groundwater). We have measured plant biomass and net primary productivity (NPP) across species, three times per year for three consecutive years, in six plots along Minqin and Linze oasis-desert ecotone (further marked as DG and SG ODE), respectively. Our results showed that DG and SG ODEs had different growth responses to different groundwater depths. DG ODE exhibited higher inter-annual variation in annual NPP (ranged from 0.18 to 9.30 g m[^-2]) than did SG ODE (ranged from 0.42 to 17.99 g m[^-2]). Decrease of groundwater depth had apparently altered the seasonality of productivity in DG ODE systems, where precipitation in summer maintained plant growth, while ODE with high groundwater depth tended to have higher spring NPP in SG ODE. Spatial and temporal heterogeneity of NPP at the scale of our measurements was significantly greater in DG ODE than in SG ODE. SG ODE tended to support higher NPP than did DG ODE. In addition, the groundwater depth strongly influenced spatial and temporal heterogeneity of NPP in the desert ecosystems. Clearly, the desert ecosystem with higher groundwater depth is more stable and more resistant to long-term drought or climate shifts in arid regions. These investigations and quantitatively analysis are very significant for the execution of conservation and restoration in arid ecosystems.

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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).

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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.