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Element enrichment and provenance of the detrital component in Holocene sediments from the Western Black Sea

100%

Dekov V. M., Darakchieva V. Y., Billstrom K., Garbe-Schonberg C. D., Kamenov G. D., Gallinari M., Dimitrov L., Ragueneau O., Kooijman E.

Oceanologia

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2020

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tom 62

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nr 2

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Assessment of heavy metals associated with bottom sediment of Asejire Reservoir, Southwest Nigeria

100%

Godwin A. I.

International Letters of Natural Sciences

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2016

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tom 55

A study on the characteristic of sediment quality of Asejire Reservoir was conducted to evaluate the heavy metal content of the reservoir. Twenty stations were selected, samples and analyzed using standard methods. The result showed that the sediment was slightly acidic across the study stations, with low conductivity and organic matter content. The heavy metals order of dominance was: Fe>Pb>Cu>Zn>Mn>Al>Ba>Ni>Cr. The mean concentration levels of all the heavy metals were lower than mean background value except Fe, Cu and Pb. However, calculated Enrichment Factor (EF) values for all the heavy metals investigated showed that they were less than 1.5 (<1.5), suggesting that the heavy metals were all derived mainly from natural sources such as bedrock materials and weathering processes.

3

Surface microlayer in lakes of different trophic status: dissolved organic matter and microbial community

100%

Kostrzewska-Szlakowska I.

Polish Journal of Ecology

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2005

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tom 53

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nr 3

The aim of this paper was to recognize the abundance and frequency of occurrence of neustonic organisms (i.e. bacteria and algae) and accumulation of organic matter in the surface microlayer of three lakes of various trophic status. Water samples of surface microlayer (0.5–0.6 mm) were taken (with Larsson plate) as well as from respective epilimnion layer (0.5 m deep). The samples were collected from shallow, humic (Sphagnum bog) lake (L. Flosek), shallow, eutrophic (L. Zełwążek) and deeper, mesotrophic lake (L. Kuc) in the period May–October during several years. The ratio of the organisms’ density in the surface microlayer to that in deeper (0.5 m) layer was considered as the enrichment factor (Ef). Heterotrophic bacteria accumulation in the surface microlayer was more frequent in the humic lake (75% of samples), than in mesoand eutrophic lakes (64%). Mean Ef values for bacteria ranged from 1.3 to 1.4. Frequent, but not strong accumulation of dissolved organic matter measured as the absorbance A₂₄₅ was noted in the surface microlayer. Dissolved organic carbon (DOC) measured in automatic analyzer showed much stronger accumulation in microlayer, particularly in humic lake. Concentration of chlorophyll a in the surface microlayer was found as the most fluctuating and the highest mean Ef value was found in the mesotrophic lake (Ef = 6.3). An attempt was undertaken to explain these differences between the lakes in terms of variable ratio between allochthonous and autochthonous production in humic, mesotrophic and eutrophic lakes.

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Distribution of metals and extent of contamination in sediments from the South-Eastern Baltic Sea (Lithuanian zone)

84%

Remeikaite-Nikiene N., Garnaga-Budre G., Lujaniene G., Joksas K., Stankevicius A., Malejevas V., Bariseviciute R.

Oceanologia

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2018

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tom 60

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nr 2

5

Assessment of arsenic enrichment of cultivated soils in Southern Poland

84%

Loska K., Wiechula D., Barska B., Cebula E., Chojnecka A.

Polish Journal of Environmental Studies

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2003

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tom 12

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nr 2

6

Heavy metals in the Baltic surface sediments

84%

Pempkowiak J., Walkusz-Miotk J.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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1994

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tom 42

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nr 1

7

Surface microlayer in lakes of different trophic status: nutrients concentration and accumulation

84%

Hillbricht-Ilkowska A., Kostrzewska-Szlakowska I.

Polish Journal of Ecology

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2004

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tom 52

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nr 4

In humic, mesotrophic and eutrophic lakes (Masurian Lakeland, Poland) 100–200 samples of water were taken with the Larsson’ plate from 0.5 mm surface microlayer (SM) and compared with the subsurface water (SSW). The concentrations of dissolved (in filtered water) and total (unfiltered) Kjeldahl nitrogen (organic and ammonium) (DKN, TKN) and phosphorus (DP, TP) were measured and the concentration of their particulate (sestonic) forms (PON, PP) estimated. The enrichment (accumulation) factor (Ef) values were calculated as the ratio of nutrients concentration in SM versus SSW. Accumulation of nutrients in SM was a common phenomena in the studied lakes. However, it occurred more frequently (close to 100% of samples) for TKN than for TP (60–70%) as well as generally more frequently in humic lake than in other lakes. Mean values of Ef for TKN were 2.6, 2.2 and 1.6 respectively for the humic, meso- and eutrophic lakes but the accumulation values for TP were lower – 2.3, 2.1 and 1.5 respectively for above lakes (the differences between concentrations in both layers as well as between lakes are significant). It means that in average the concentration of N and P in SM is at least two times greater than in SSW in humic and mesotrophic lakes. Accumulation of particulate forms of nutrients (PP, PKN) in SM is less frequent but the respective values of Ef are higher comparing with the total content of these nutrients and again higher for nitrogen than phosphorus. The higher values of the weight ration N:P (33–76) in seston were found in SM in comparison with SSW (24–56) as well as higher contribution of particulate (sestonic) N (PON) to its total content in respective layer. Generally higher values of these two indices were found in both layers of humic lake than in other lakes. No significant differences were found for the Ef values calculated for spring and summer periods (expected to differ in organic matter production and algae biomass) as well as for different sites (open water, shore region) in the lakes. It was concluded that the humic substances of allochthonous origin (mostly refractory and of high molecular weight) possibly predominate in the surface microlayer of the humic lake and support the stability and specificity of this layer in comparison with deeper water layer as well as in comparison with the meso- and eutrophic lakes. In highly productive, eutrophic lake, the surface microlayer is less distinct and stable possibly because of relatively greater role of in situ autochthonous production of labile organic matter which shows low affinity to the air-water interface. The surface microlayer in mesotrophic lake displays somehow intermediate properties in comparison with humic and eutrophic lakes.

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Nitrogen and phosphorus exchange in the contact zone between the sea and the atmosphere

67%

Falkowska L., Bolalek J.

Oceanologia

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1991

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tom 30

9

Precipitation chemistry in a forested study area of the Chojnow Forest District in the years 2004–2007

67%

Kowalska A., Janek M.

Journal of Water and Land Development

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2009

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nr 13a

Ograniczanie wyników

Element enrichment and provenance of the detrital component in Holocene sediments from the Western Black Sea

Assessment of heavy metals associated with bottom sediment of Asejire Reservoir, Southwest Nigeria

Surface microlayer in lakes of different trophic status: dissolved organic matter and microbial community

Distribution of metals and extent of contamination in sediments from the South-Eastern Baltic Sea (Lithuanian zone)

Assessment of arsenic enrichment of cultivated soils in Southern Poland

Heavy metals in the Baltic surface sediments

Surface microlayer in lakes of different trophic status: nutrients concentration and accumulation

Nitrogen and phosphorus exchange in the contact zone between the sea and the atmosphere

Precipitation chemistry in a forested study area of the Chojnow Forest District in the years 2004–2007