The Evaluation of the Concentration of Bivalent Basic Cations in Surface Water of the National Nature Reserve Čičov Oxbow

Abstract During the years 2013–2014, the concentrations of bivalent basic cations Ca2+ and Mg2+ were evaluated in the water of the Čičov tributary, which belongs to the National Nature Reserve of the basin of the river Danube. On the basis of the results obtained, it can be stated that the average concentration of calcium for the whole reference period was 59.63 mg.dm−3. Minimum average concentration depending on the time of sampling was found in November (48.42 mg.dm−3) and maximum in July (70.73 mg.dm−3). We assume that this above average concentrations in the summer could be due to the lower surface of the water due to higher evaporation. Depending on the places of sampling points, the lowest average concentration (58.10 mg.dm−3) for the whole reference period was at the mouth of the Čilizian brook and the top (60.32 mg.dm−3) in the first side shoulder. The analysis of variance detected highly statistically significant effect of the year and month of collection on changes in the concentration of calcium. The average concentration of magnesium for the whole reference period was 14.54 mg.dm−3. As for the time of collection, the highest average concentrations for the entire observation period were found during the summer, with the maximum average concentration in July (16.94 mg.dm−3) and minimum in February (10.81 mg.dm−3). The lowest average magnesium concentration for the entire reference period, regarding to the sampling points, was measured in the north-eastern part of the nature reserve (14.28 mg.dm−3) and the highest one at the mouth of the Čilizian brook into the National Nature Reserve (14.72 mg.dm−3).

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Grassland communities of the Verlorenvalei Nature Reserve in the North-eastern Sandy Highveld, Transvaal

South African Journal of Botany ◽

10.1016/s0254-6299(16)30728-1 ◽

1993 ◽

Vol 59 (3) ◽

pp. 273-280 ◽

Cited By ~ 3

Author(s):

K.J. Bloem ◽

G.K. Theron ◽

N. van Rooyen

Keyword(s):

Nature Reserve ◽

The North ◽

North Eastern ◽

Grassland Communities

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Contrasting controls on Congo Basin evaporation at the two rainfall peaks

Climate Dynamics ◽

10.1007/s00382-020-05547-1 ◽

2020 ◽

Author(s):

David Crowhurst ◽

Simon Dadson ◽

Jian Peng ◽

Richard Washington

Keyword(s):

Sensible Heat Flux ◽

Vapour Pressure Deficit ◽

Lower Surface ◽

Congo Basin ◽

Shortwave Radiation ◽

Net Radiation ◽

Area Index ◽

The North ◽

North Eastern ◽

Main Component

AbstractEvaporation is a crucial driver of Congo Basin climate, but the dynamics controlling the seasonality of basin evaporation are not well understood. This study aims to discover why evaporation on the basin-wide average is lower at the November rainfall peak than the March rainfall peak, despite similar rainfall. Using 16-year mean LandFlux-EVAL data, we find that evaporation is lower in November than March in the rainforest and the eastern savannah. The ERA5-Land reanalysis, which effectively reproduces this pattern, shows that transpiration is the main component responsible for lower evaporation in these regions. Using ERA5-Land, we find the following contrasting controls on transpiration, and therefore evaporation, at the two rainfall peaks: (a) In the northern rainforest, there is lower leaf area index (LAI) in November, driven by lower surface downward shortwave radiation (DSR), and lower vapour pressure deficit (VPD) in November, driven by lower sensible heat flux that results from lower net radiation. The combination of lower LAI and VPD explains lower transpiration, and therefore lower evaporation, in November. (b) In the southern rainforest, and in the north-eastern savannah, there is lower LAI in November, driven by lower surface DSR, and this explains lower transpiration, and therefore lower evaporation, in November. (c) In the south-eastern savannah, there is lower LAI in November, driven by lower volumetric water content (VWC), and this explains lower transpiration, and therefore lower evaporation, in November. Collectively, these contrasting controls at the two rainfall peaks explain why the basin-wide average evaporation is lower in November than March.

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Changes in Concentrations of Monovalent Basic Cations in the Water of the Čaradice Stream / Zmeny Koncentrácií Jednomocných Bázických Katiónov vo vode Vodného toku Čaradický Potok

Acta Horticulturae et Regiotecturae ◽

10.2478/ahr-2013-0002 ◽

2013 ◽

Vol 16 (1) ◽

pp. 4-9

Author(s):

Jaroslav Noskovič ◽

Eva Candráková ◽

Mária Babošová ◽

Jana Porhajašová

Keyword(s):

Analysis Of Variance ◽

Forest Ecosystem ◽

Slovak Republic ◽

Average Concentration ◽

Reference Period ◽

Spring Season ◽

Qualitative Factors ◽

The Government ◽

The Village ◽

Basic Cations

Abstract In the years 2005-2010, the changes in concentrations of monovalent basic cations in the Čaradice Stream were evaluated depending on the time and place of sampling in its longitudinal profile. Results show that the average concentration of Na+ in the whole period was 14.75 mg. dm-3. Its share in the total amount of monovalent basic cations of Na+ and K+ in the whole reference period was 76.32%. The mass ratio of Na+ : K+ in the whole period was 3.34 : 1. Depending on the time of sampling, the lowest average sodium concentrations of the whole period were recorded in the spring season with the minimum average in March. The highest average concentration of the whole reference period was recorded in September. Depending on the sampling site, the minimum average concentration was recorded in a forest ecosystem and an ecosystem of permanent grassland, and the maximum average concentration in the village Kozarovce. Using the analysis of variance, we detected a statistically significant effect of all three qualitative factors (year, month and place of sampling) on the change of concentration. According to the Regulation of the Government of the Slovak Republic No. 269/2010 Coll., the 90th percentile values of this indicator are lower than the recommended value. The average concentration of potassium in the whole reference period was 4.54 mg. dm-3. The share of K+ in the total amount of monovalent basic cations in the whole period reached 23.68%. The lowest average concentrations of the whole period were usually found in the spring season, with the minimum value in March. The maximum average concentration of the whole reference period was recorded in July. Similarly to Na+, the lowest average concentration of K+ was detected in a forest ecosystem and the highest one in the village Kozarovce. The effect of seasonality on the dynamics of Na+ and K+ concentrations during the period was not detected. Using the analysis of variance, we found a statistically significant effect of all three qualitative factors (year, month and place of sampling) on the change of concentration. In the Regulation of the Government of the Slovak Republic No. 269/2010 Coll., the recommended value for potassium is not specified. The discharge rate significantly affected the changes in concentrations of Na+ and K+ in the stream.

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Wetland plant communities of the Verlorenvalei Nature Reserve in the North-eastern Sandy Highveld, Transvaal

South African Journal of Botany ◽

10.1016/s0254-6299(16)30729-3 ◽

1993 ◽

Vol 59 (3) ◽

pp. 281-286 ◽

Cited By ~ 5

Author(s):

K.J. Bloem ◽

G.K. Theron ◽

N. van Rooyen

Keyword(s):

Plant Communities ◽

Nature Reserve ◽

Wetland Plant ◽

The North ◽

Wetland Plant Communities ◽

North Eastern

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Discussion on “The grinding wheel and production” at the North-Eastern Section of the Institution

Journal of the Institution of Production Engineers ◽

10.1049/jipe.1942.0023 ◽

1942 ◽

Vol 21 (8) ◽

pp. 315

Author(s):

Bowen ◽

Vickery ◽

Buchanan ◽

Swallow ◽

Perks ◽

...

Keyword(s):

Grinding Wheel ◽

The North ◽

North Eastern

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The influence of submesoscale eddies on hydrochemical parameters and structural and functional characteristics of phytoplankton in the north-eastern part of the Black Sea

Hydrosphere Еcology (Экология гидросферы) ◽

10.33624/2587-9367-2019-1(3)-24-40 ◽

2019 ◽

pp. 24-40

Author(s):

Sergey B. Kuklev ◽

Vladimir A. Silkin ◽

Valeriy K. Chasovnikov ◽

Andrey G. Zatsepin ◽

Larisa A. Pautova ◽

...

Keyword(s):

Anticyclonic Eddy ◽

The Black Sea ◽

Hydrochemical Parameters ◽

North East ◽

The North ◽

Seasonal Thermocline ◽

North Eastern ◽

Quantitative Indicators ◽

The City ◽

North Eastern Part

On June 7, 2018, a sub-mesoscale anticyclonic eddy induced by the wind (north-east) was registered on the shelf in the area of the city of Gelendzhik. With the help of field multidisciplinary expedition ship surveys, it was shown that this eddy exists in the layer above the seasonal thermocline. At the periphery of the eddy weak variability of hydrochemical parameters and quantitative indicators of phytoplankton were recorded. The result of the formation of such eddy structure was a shift in the structure of phytoplankton – the annual observed coccolithophores bloom was not registered.

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