Wyniki wyszukiwania

1

Changes in nutrient concentrations in upwelling border areas at north-west coast of Africa

100%

Juchnowicz-Bierbasz M.

Polskie Archiwum Hydrobiologii

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1999

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tom 46

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nr 1

2

Concentration of nutrients in the soil in water-level-fluctuating zone of Three Gorges Reservoir

86%

Zhang B., Guo J.-S., Fang F., Li Z., Fu C.

International Journal of Ecohydrology and Hydrobiology

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2012

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tom 12

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nr 2

3

Fungi biomass in lowland rivers of North-Eastern Poland: effects of habitat conditions and nutrient concentration

86%

Gorniak A., Wiecko A., Cudowski A.

Polish Journal of Ecology

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2013

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tom 61

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nr 4

Fungi occur in almost all types of waters in the world and play an important role in many processes in the environment, particularly in organic matter decomposition. During the last several decades, extensive knowledge was obtained on the ecology of aquatic fungi, but on fungal biomass in the water column less. The study was aimed at simultaneous determination of seasonal and spatial variability of aquatic fungi biomass in the river waters in relation to selected physicochemical water parameters and trophic state in the 27 lowland rivers of north-eastern Poland with length between 17 and 308 km and mean annual discharge 1 – 100 m³ s⁻¹. The chemical and mycological evaluation was provided on the basis of 64 water samples taken in the July and October 2010. The chromatographic method of determination of seston ergosterol as a specific organic compound typical for the majority of fungi, was applied. Fungi biomass was higher in summer than in autumn. The particulate organic carbon (POC) and dissolved organic carbon (DOC) concentrations had no effect on fungal biomass in the studied river, as well as forest cover of the catchment and river discharge. Statistically significant correlations of fungal biomass in the river water with concentrations of ammonium (N–NH₄⁺), Kjeldahl (NKjel), total organic (TON) and total nitrogen (TN) and dissolved (DP) and dissolved organic phosphorus (DOP) were found. The principal component analysis indicates relations between (TIN) and phosphorus (SRP) and particulate phosphorus (PP) and freshwater fungi, specially in summer when aquatic fungi are able to modify the structure of the nutrients contained in the water column.

4

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The influence of soil acidity on aluminium and mineral nutrients concentrations in soil solution at different soil water potentials

86%

Siecinska J., Wiacek D., Nosalewicz A.

Acta Agrophysica

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2016

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tom 23

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nr 1

The aim of the research was to analyse the impact of soil water potential on the concentration of aluminium and selected mineral nutrients in soil solution. Soil acidification is a natural process accelerated by agriculture, and one of the most important factors limiting crop production worldwide. Concentrations of aluminium and selected mineral nutrients in solutions obtained from soil at initial pH 4.2 and after liming at various soil water potential were measured in centrifuged soil solution. Our results showed a significant gradual increase in the concentration of Al and most of mineral nutrients (Ca, Mg and P) with decreasing soil water potential from −3.5 kPa to −0.205 MPa. The results are important in the evaluation and interpretation of plant response to aluminium toxicity when accompanied by changes in water availability.

5

Average nutrient and chlorophyll distributions in the Western Mediterranean: RADMED project

86%

Garcia-Martinez M. C., Vargaz-Yanez M., Moya F., Santiago R., Munoz M., Reul A., Ramirez T., Balbin R.

Oceanologia

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2019

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tom 61

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nr 1

6

A numerical investigation of nutrient concentrations in Gdansk Gulf as revealed by a coupled one-dimensional model

86%

Dzierzbicka-Glowacka L.

Polish Journal of Environmental Studies

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2006

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tom 15

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nr 1

A dynamics model for nutrients was coupled with a one-dimensional physical and biological upper layer model to simulate the temporal changes not only in distributions of a nutrient but then of phytoplankton and zooplankton and study the role of these biological characteristics in the dynamics of the Gdańsk Gulf ecosystem. The 1D model consists of three submodels: a meteorological submodel for the physics of the upper layer and a biological submodel, which also is driven by output from the physical submodel. The biological upper layer model {nutrient-phytoplankton-zooplankton-detritus} incorporates formulations of the primary production mechanism and of the remineralization mechanisms within the mixed layer, in the lower layers and at the bottom as well as of the daily migration of zooplankton mechanism. The model is based on total inorganic nitrogen (NO3+NO2+NH4) and phosphate (PO4). The calculations were made for 180 days (from March to August) for two stations at Gdańsk Gulf (at station A, near the Vistula river mouth, and at station B, located further to the open sea). The results of the numerical investigations described here were compared with the mean observed values of characteristics investigated for 10 years, 1990-2000. Comparison of computed and measured values shows the model reproduces the time-vertical structure of characteristics investigated in accordance with the in situ observations. The numerical simulations shown that the differences between the simulated and mean observed values of nutrient in the upper layer are c. 1 mmol m⁻³ for total inorganic nitrogen and 0.1 mmol m-3 for phosphate. The slight differences between the calculated and observed values of surface chlorophyll-a and microzooplankton biomass are ca. 5-20%, depending on the location of the hydrographic station and the month for which the calculations were made. The model can be used to describe the temporal patterns for nutrients distributions and phytoplankton and zooplankton biomass.

7

Seasonal fluctuations and long-term trends of nutrient concentrations in the Polish zone of the Baltic Sea

72%

Trzosinska A.

Oceanologia

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1990

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tom 29

8

Seasonal changes of nutrients concentration in two shallow estuarine lakes gardno and Lebsko; Comparison

72%

Jarosiewicz A.

Baltic Coastal Zone. Journal of Ecology and Protection of the Coastline

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2009

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tom 13 part I

The aim of this paper was the presentation and comparison of seasonal biogens changes and trophy state classification of two biggest shallow coastal lakes Gardno and Łebsko, located in the northern part of Poland, along the southern coast of the Baltic Sea. Measurements were conducted once a month from April to December 2007. For the purpose of this article at each lake one measurement station was selected, to represent well mixed area of the lakes, far from outlet to the sea and rivers. Performed measurements showed that the lakes are similar. The differences, observed between biogens concentration in lakes were statistically insignificant. Seasonal dynamics of nutrients concentration in lakes indicated that the lakes are typical shallow lakes. Moreover, the summer concentration of total nitrogen and phosphorus qualify these lakes as eutrophic.

9

Dinophyta characterise nitrogen scarcity more strongly than Cyanobacteria in moderately deep lakes

72%

Fisher J., James C. S., Moore V. L., Moss B.

Acta Protozoologica

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2013

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tom 52

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nr 3

10

A review of the diatom research in the Gulf of Gdansk and Vistula Lagoon (Southern Baltic Sea)

72%

Witak M.

Oceanological and Hydrobiological Studies

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2013

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tom 42

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nr 3

11

Influence of the winter phytoplankton bloom on the settled material in a temperate shallow estuary

72%

Guinder V. A., Lopez-Abbate M. C., Berasategui A. A., Negrin V. L., Zapperi G., Pratolongo P. D., Fernandez Severini M. D., Popovich C. A.

Oceanologia

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2015

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tom 57

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nr 1

12

Growth rate of duckweeds (Lemnaceae) in relation to the internal and ambient nutrient concentrations - testing the Droop and Monod models

72%

Kufel L., Strzalek M., Wysokinska U., Biardzka E., Okninska S., Rys K.

Polish Journal of Ecology

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2012

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tom 60

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nr 2

The Monod model describes the relationship between growth rate and ambient nutrient concentration, the Droop model focuses on internal nutrient resources as the driving factor. Both were applied mainly to explain phytoplankton dynamics in lakes or in experimental cultures. Our test plants were two species of duckweeds – Lemna minor L. and Spirodela polyrhiza (L.) Schleiden sampled from 18 natural stands situated in 6 different water bodies. Plants were grown outdoor in original lake water or in mineral media of varying N and P concentrations (0–21 mg N-NO3 L-1 and 0–1853 μg P-PO4 L-1 for L.minor and 0–4.2 mg N-NO3 L-1 and 0–371 μg P-PO4 L-1 for S. polyrhiza). Moreover, we analysed concentrations of mineral forms of N and P in lake water and tissue nutrient concentrations in plants. Tissue N of both plants was significantly correlated with ambient inorganic nitrogen sources, no such relationship was observed for tissue P. The growth rate of both plants measured under experimental outdoor conditions was better explained by tissue N and P variability (the Droop model) than by the external nutrient availability (the Monod model). The latter also failed to fit the growth rate of both plants in artificial mineral media with a decreasing gradient of N and P concentrations. The plants grew at the expense of internal N and P resources which remarkably declined during 9-day long experiments. Calculated minimum tissue contents (11.19 ± 1.11 mg N g-1 and 0.97 ± 0.07 mg P g-1 in L. minor and 6.10 ± 1.85 mg N and 1.25 ± 0.37 mg P g-1 in S. polyrhiza) show that the latter species would be a superior competitor under N limiting conditions and the former – under P limitation. We confront obtained results with literature data on N uptake kinetics and postulate that the luxury consumption of nutrients and plant growth dependent mainly on internal N and P resources might be an adaptation of duckweeds to varying habitat conditions typical of astatic water bodies.

13

Deposition, return flux, and burial rates of nitrogen and phosphorus in the sediments of two high-Arctic fjords

72%

Koziorowska K., Kulinski K., Pempkowiak J.

Oceanologia

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2018

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tom 60

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nr 4

14

Analysis of long-term variations in physico-chemical parameters of seawater in the Southern Baltic Sea; an approach to incomplete data series

72%

Lysiak-Pastuszak E., Cyberski J.

Oceanologia

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1999

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tom 41

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nr 4

15

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

72%

Kowalewski M.

Oceanologia

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2005

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tom 47

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nr 4

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 Gdańskwith a 1 NM grid spacing. Validation indicated good agreement between model results and measurements in the GdańskD eep, 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 Gdańskb y 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.

16

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

72%

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.

17

Dynamics of dissolved nutrients in forest floor leachates: comparison of a natural forest ecosystem with monoculture tree species plantations in south-east Ethiopia

58%

Ashagrie Y., Zech W.

International Journal of Ecohydrology and Hydrobiology

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2010

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tom 10

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nr 2-4

The dynamics of nutrients in water passing through the forest floors of two plantation forests (Cupressus lusitanica and Eucalyptus globulus) and an adjacent natural forest were monitored over a one year period at Munesa, Ethiopia. The results showed that, in all forest types, after K, Ca and Cl were the most abundant nutrients leached from the forest floor to the mineral soil. The concentration of NO3–N in the natural forest was about 10 times higher than that of NH4–N, but 8 and 3 times higher than that of NH4–N under Eucalyptus and Cupressus, respectively. No significant differences in concentrations of most of the nutrients were observed among forest types, but magnesium and NO3–N were significantly higher under the natural forest and Eucalyptus than under Cupressus. Except for NH4–N, which was depleted in relation to throughfall in the natural forest, the concentrations of all other nutrients were enriched in litter leachate in relation to both rainfall and throughfall. However, with the exceptions of NO3–N in all forest types, Ca under Cupressus and PO4–P under Cupressus and Eucalyptus, all measured nutrient fluxes from the forest floor to the mineral soil decreased in relation to throughfall fluxes. Generally, the results show that despite the differences in tree species composition among the forest types the organic layer acted as a sink for most of the nutrients coming via throughfall.

18

Ecosystem of the Polish part of the Vistula Lagoon from the perspective of alternative stable states concept, with implications for management issues

58%

Kornijow

Oceanologia

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2018

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tom 60

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nr 3

19

The role of emergent macrophytes in nutrient cycling in Lake Niepruszewskie (Western Poland)

58%

Lawniczak A. E.

Oceanological and Hydrobiological Studies

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2010

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tom 39

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nr 2

20

Phytoplankton and environmental variables as a water quality indicator for the beaches at Matrouh, South-Eastern Mediterranean Sea, Egypt: an assessment

58%

Gharib S. M., El-Sherif Z. M., Abdel-Halim A. M., Radwan A. A.

Oceanologia

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2011

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tom 53

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nr 3

This study was carried out to determine the water quality of the beaches at Matrouh, south-eastern Mediterranean Sea, Egypt, by studying environmental variables as well as phytoplankton abundance and community structure. Surface water samples were monitored from a series of beach sites over a period of five seasons during 2009–2010. A total of 203 phytoplankton species were identified from seven algal divisions. Seasonal differences in the quantitative and qualitative composition of the phytoplankton communities in the different sites were marked. Nutrient concentrations and phytoplankton abundances were found to be poorer than those of many other areas along Egyptian coast. The Shannon-Wiener Diversity Index classified Matrouh water as being between clean and moderately polluted, whereas the WQI demonstrated that it was between good and excellent. It can be concluded that the index based onWQI is currently more suitable than the phytoplankton species index for assessing the quality of the water of the Matrouh beaches.

Ograniczanie wyników

Changes in nutrient concentrations in upwelling border areas at north-west coast of Africa

Concentration of nutrients in the soil in water-level-fluctuating zone of Three Gorges Reservoir

Fungi biomass in lowland rivers of North-Eastern Poland: effects of habitat conditions and nutrient concentration

The influence of soil acidity on aluminium and mineral nutrients concentrations in soil solution at different soil water potentials

Average nutrient and chlorophyll distributions in the Western Mediterranean: RADMED project

A numerical investigation of nutrient concentrations in Gdansk Gulf as revealed by a coupled one-dimensional model

Seasonal fluctuations and long-term trends of nutrient concentrations in the Polish zone of the Baltic Sea

Seasonal changes of nutrients concentration in two shallow estuarine lakes gardno and Lebsko; Comparison

Dinophyta characterise nitrogen scarcity more strongly than Cyanobacteria in moderately deep lakes

A review of the diatom research in the Gulf of Gdansk and Vistula Lagoon (Southern Baltic Sea)

Influence of the winter phytoplankton bloom on the settled material in a temperate shallow estuary